The main idea of reinforcement learning is evaluating the chosen action depending on the current reward.According to this concept,many algorithms achieved proper performance on classic Atari 2600 games.The main challe...The main idea of reinforcement learning is evaluating the chosen action depending on the current reward.According to this concept,many algorithms achieved proper performance on classic Atari 2600 games.The main challenge is when the reward is sparse or missing.Such environments are complex exploration environments likeMontezuma’s Revenge,Pitfall,and Private Eye games.Approaches built to deal with such challenges were very demanding.This work introduced a different reward system that enables the simple classical algorithm to learn fast and achieve high performance in hard exploration environments.Moreover,we added some simple enhancements to several hyperparameters,such as the number of actions and the sampling ratio that helped improve performance.We include the extra reward within the human demonstrations.After that,we used Prioritized Double Deep Q-Networks(Prioritized DDQN)to learning from these demonstrations.Our approach enabled the Prioritized DDQNwith a short learning time to finish the first level of Montezuma’s Revenge game and to perform well in both Pitfall and Private Eye.We used the same games to compare our results with several baselines,such as the Rainbow and Deep Q-learning from demonstrations(DQfD)algorithm.The results showed that the new rewards system enabled Prioritized DDQN to out-perform the baselines in the hard exploration games with short learning time.展开更多
In this paper, a detailed theoretical study on the characteristics of cone-shaped inwall capillary-based microsphere resonators is described and demonstrated for sensing applications. The maximum, minimum, slope, cont...In this paper, a detailed theoretical study on the characteristics of cone-shaped inwall capillary-based microsphere resonators is described and demonstrated for sensing applications. The maximum, minimum, slope, contrast, and width of the Fano resonance are analyzed. As the transmission coefficient of the capillary resonator increases, the absolute value of the slope of Fano resonances increases to reach its maximum, which is useful for sensors with an ultra-high sensitivity. There occurs another phenomenon of electromagnetically induced transparency when the reflectivity at the capillary–environment interface is close to 100%. We also experimentally demonstrated its capability for temperature and refractive index sensing, with a sensitivity of 10.9 pm∕°C and 431 d B∕RIU basedon the Fano resonance and the Lorentzian line shape, respectively.展开更多
Autonomous planning is a significant development direction of the space manipulator,and learning from demonstrations(LfD)is a potential strategy for complex tasks in the field.However,separating control from planning ...Autonomous planning is a significant development direction of the space manipulator,and learning from demonstrations(LfD)is a potential strategy for complex tasks in the field.However,separating control from planning may cause large torque fluctuations and energy consumptions,even instability or danger in control of space manipulators,especially for the planning based on the human demonstrations.Therefore,we present an autonomous planning and control strategy for space manipulators based on LfD and focus on the dynamics uncertainty problem,a common problem of actual manipulators.The process can be divided into three stages:firstly,we reproduced the stochastic directed trajectory based on the Gaussian process-based LfD;secondly,we built the model of the stochastic dynamics of the actual manipulator with Gaussian process;thirdly,we designed an optimal controller based on the dynamics model to obtain the improved commanded torques and trajectory,and used the separation theorem to deal with stochastic characteristics during control.We evaluated the strategy with locating pre-screwed bolts experiment by Tiangong-2 manipulator system on the ground.The result showed that,compared with other strategies,the strategy proposed in this paper could significantly reduce torque fluctuations and energy consumptions,and its precision can meet the task requirements.展开更多
The national independent innovation demonstration zone(NIIDZ)is an independent innovation policy that plays a crucial role in implementing strategies.Given the importance of the NIIDZ,this study uses panel data of 278...The national independent innovation demonstration zone(NIIDZ)is an independent innovation policy that plays a crucial role in implementing strategies.Given the importance of the NIIDZ,this study uses panel data of 278 prefecture-level cities in China from 2006 to 2020 and empirically examines the effect and internal mechanism of the NIIDZ on green economic efficiency(GEE)using the difference-in-difference model(DID).The results show that the NIIDZ effectively enhances the growth of GEE,and the results remain valid through several robustness tests,such as year-by-year propensity score matching.The transmission mechanism suggests that the NIIDZ indirectly drives GEE by accelerating scientific and technological investment,promoting talent concentration,and optimizing the industrial structure.Moreover,heterogeneity analysis reveals that the promotion effect of the NIIDZ on GEE is more prominent in the eastern region and high green development level areas.The study’s findings can serve as a reference for China to further utilize the policy effectiveness of the NIIDZ and accelerate the high-quality development of the green economy in the future.展开更多
Yimeng red culture is an important part of the excellent culture of the Chinese nation.It is of great practical significance and long-term strategic significance to build the demonstration area for the inheritance and...Yimeng red culture is an important part of the excellent culture of the Chinese nation.It is of great practical significance and long-term strategic significance to build the demonstration area for the inheritance and development of Yimeng red culture.Combining digital empowerment with the inheritance and development of Yimeng red culture is a new idea that conforms to the development of the times.In this paper,on the basis of combing Yimeng red cultural resources and combining with the current situation of inheritance and development of Yimeng red culture,the strategic layout and implementation approach of the demonstration area for the inheritance and development of Yimeng red culture were put forward from the perspective of digital empowerment.展开更多
Considering Pythagorician divisors theory which leads to a new parameterization, for Pythagorician triplets ( a,b,c )∈ ℕ 3∗ , we give a new proof of the well-known problem of these particular squareless numbers n∈ ℕ...Considering Pythagorician divisors theory which leads to a new parameterization, for Pythagorician triplets ( a,b,c )∈ ℕ 3∗ , we give a new proof of the well-known problem of these particular squareless numbers n∈ ℕ ∗ , called congruent numbers, characterized by the fact that there exists a right-angled triangle with rational sides: ( A α ) 2 + ( B β ) 2 = ( C γ ) 2 , such that its area Δ= 1 2 A α B β =n;or in an equivalent way, to that of the existence of numbers U 2 , V 2 , W 2 ∈ ℚ 2∗ that are in an arithmetic progression of reason n;Problem equivalent to the existence of: ( a,b,c )∈ ℕ 3∗ prime in pairs, and f∈ ℕ ∗ , such that: ( a−b 2f ) 2 , ( c 2f ) 2 , ( a+b 2f ) 2 are in an arithmetic progression of reason n;And this problem is also equivalent to that of the existence of a non-trivial primitive integer right-angled triangle: a 2 + b 2 = c 2 , such that its area Δ= 1 2 ab=n f 2 , where f∈ ℕ ∗ , and this last equation can be written as follows, when using Pythagorician divisors: (1) Δ= 1 2 ab= 2 S−1 d e ¯ ( d+ 2 S−1 e ¯ )( d+ 2 S e ¯ )=n f 2;Where ( d, e ¯ )∈ ( 2ℕ+1 ) 2 such that gcd( d, e ¯ )=1 and S∈ ℕ ∗ , where 2 S−1 , d, e ¯ , d+ 2 S−1 e ¯ , d+ 2 S e ¯ , are pairwise prime quantities (these parameters are coming from Pythagorician divisors). When n=1 , it is the case of the famous impossible problem of the integer right-angled triangle area to be a square, solved by Fermat at his time, by his famous method of infinite descent. We propose in this article a new direct proof for the numbers n=1 (resp. n=2 ) to be non-congruent numbers, based on an particular induction method of resolution of Equation (1) (note that this method is efficient too for general case of prime numbers n=p≡a ( ( mod8 ) , gcd( a,8 )=1 ). To prove it, we use a classical proof by induction on k , that shows the non-solvability property of any of the following systems ( t=0 , corresponding to case n=1 (resp. t=1 , corresponding to case n=2 )): ( Ξ t,k ){ X 2 + 2 t ( 2 k Y ) 2 = Z 2 X 2 + 2 t+1 ( 2 k Y ) 2 = T 2 , where k∈ℕ;and solutions ( X,Y,Z,T )=( D k , E k , f k , f ′ k )∈ ( 2ℕ+1 ) 4 , are given in pairwise prime numbers.2020-Mathematics Subject Classification 11A05-11A07-11A41-11A51-11D09-11D25-11D41-11D72-11D79-11E25 .展开更多
In actor-critic reinforcement learning(RL)algorithms,function estimation errors are known to cause ineffective random exploration at the beginning of training,and lead to overestimated value estimates and suboptimal p...In actor-critic reinforcement learning(RL)algorithms,function estimation errors are known to cause ineffective random exploration at the beginning of training,and lead to overestimated value estimates and suboptimal policies.In this paper,we address the problem by executing advantage rectification with imperfect demonstrations,thus reducing the function estimation errors.Pretraining with expert demonstrations has been widely adopted to accelerate the learning process of deep reinforcement learning when simulations are expensive to obtain.However,existing methods,such as behavior cloning,often assume the demonstrations contain other information or labels with regard to performances,such as optimal assumption,which is usually incorrect and useless in the real world.In this paper,we explicitly handle imperfect demonstrations within the actor-critic RL frameworks,and propose a new method called learning from imperfect demonstrations with advantage rectification(LIDAR).LIDAR utilizes a rectified loss function to merely learn from selective demonstrations,which is derived from a minimal assumption that the demonstrating policies have better performances than our current policy.LIDAR learns from contradictions caused by estimation errors,and in turn reduces estimation errors.We apply LIDAR to three popular actor-critic algorithms,DDPG,TD3 and SAC,and experiments show that our method can observably reduce the function estimation errors,effectively leverage demonstrations far from the optimal,and outperform state-of-the-art baselines consistently in all the scenarios.展开更多
Burundi and China enjoy close collaboration in a number of sectors,particularly agriculture.Among the major initiatives,the introduction of hybrid rice cultivation stands out as a flagship project.In 2018,the first de...Burundi and China enjoy close collaboration in a number of sectors,particularly agriculture.Among the major initiatives,the introduction of hybrid rice cultivation stands out as a flagship project.In 2018,the first demonstration village for hybrid rice cultivation was established in the commune of Gihanga in northwestern Burundi.In 2020,this initiative reached a crucial stage with the creation of the Burundi Agricultural Pilot Centre(APC),located in Gihanga in the province of Bubanza.A total of 56 villages spread across 11 of Burundi’s 18 provinces have been selected for demonstration as of now.Yang Huade,head of the team of high-level Chinese agricultural experts supporting Burundi and a rice cultivation specialist who is also in charge of the APC,revealed that trials are currently underway in four provinces:the capital Gitega,the central province of Muramvya,and the northern provinces of Ngozi and Kayanza.展开更多
With the rapid development of industrialisation and urbanisation, China is facing the challenge of severe HF (Haze-Fog) pollution. This essay compares the advantages and disadvantages of China’s HF management and sum...With the rapid development of industrialisation and urbanisation, China is facing the challenge of severe HF (Haze-Fog) pollution. This essay compares the advantages and disadvantages of China’s HF management and summarizes the important lessons China can teach the rest of the world about applying this tactic. China’s capabilities in the digital economy, National Innovation Demonstration Zones, and urban innovation systems are examined in this article, along with its shortcomings in information mechanisms and pollution sources. This essay also summarizes China’s achievements, particularly regarding local autonomy. The essay goes on to say, however, that China is probably going to be under more pressure to manage HF in the future, both in terms of long-term solutions and the economy.展开更多
Taking the National Experimental Teaching Demonstration Center of the Central Academy of Drama as an example,this article explores the construction and development of the National Experimental Teaching Demonstration C...Taking the National Experimental Teaching Demonstration Center of the Central Academy of Drama as an example,this article explores the construction and development of the National Experimental Teaching Demonstration Center for the practical teaching of drama and film and television disciplines.The article first introduces the background and importance of the demonstration center and then analyzes in depth the construction content and achievements of the demonstration center from four aspects:practical teaching philosophy,practical teaching system,practical teaching resources,and practical teaching effects.Finally,the article summarizes the experience and shortcomings of the demonstration center and proposes future development directions and suggestions.展开更多
In this paper, we propose a new prediction from expert demonstration (PED) methodology to improve reliability and safety in tele-surgery. Data was collected from expert (clinician) demonstrations for the procedure...In this paper, we propose a new prediction from expert demonstration (PED) methodology to improve reliability and safety in tele-surgery. Data was collected from expert (clinician) demonstrations for the procedure of trocar insertion. We encoded a set of force, torque and penetration trajectories by using a Gaussian mixture model (GMM). A generalization of these profiles and associated parameters were retrieved by Gaussian mixture regression (GMR). We validated the proposed methodology for tele-robotic placement of the trocar in two stages. First, we tested the efficacy of the proposed PED approach for handling transmission error and latency. Our results showed that for the average case (12% packet error and 1070 loss of packet), a 58.8~0 improvement in performance was obtained in comparison to using an extended Kalman filter. Next, we validated the methodology for surgical assistance on 15 participants. A haptic assistance mode was devised based on the proposed PED model to assist inexperienced operators to perform the procedure. The PED model was tested for instrument deviation, penetration force and penetration depth. Preliminary study results showed that participants with PED assistance performed the task with more consistency and exerted lesser penetration force than subjects without assistance.展开更多
A research arena(WARA-PS)for sensing,data fusion,user interaction,planning and control of collaborative autonomous aerial and surface vehicles in public safety applications is presented.The objective is to demonstrate...A research arena(WARA-PS)for sensing,data fusion,user interaction,planning and control of collaborative autonomous aerial and surface vehicles in public safety applications is presented.The objective is to demonstrate scientific discoveries and to generate new directions for future research on autonomous systems for societal challenges.The enabler is a computational infrastructure with a core system architecture for industrial and academic collaboration.This includes a control and command system together with a framework for planning and executing tasks for unmanned surface vehicles and aerial vehicles.The motivating application for the demonstration is marine search and rescue operations.A state-of-art delegation framework for the mission planning together with three specific applications is also presented.The first one concerns model predictive control for cooperative rendezvous of autonomous unmanned aerial and surface vehicles.The second project is about learning to make safe real-time decisions under uncertainty for autonomous vehicles,and the third one is on robust terrain-aided navigation through sensor fusion and virtual reality tele-operation to support a GPS-free positioning system in marine environments.The research results have been experimentally evaluated and demonstrated to industry and public sector audiences at a marine test facility.It would be most difficult to do experiments on this large scale without the WARA-PS research arena.Furthermore,these demonstrator activities have resulted in effective research dissemination with high public visibility,business impact and new research collaborations between academia and industry.展开更多
Sustainable development is the central theme of modern global development.With the arrival of the urban era,the vulnerability and instability of rural areas have significantly increased,and rural sustainable developme...Sustainable development is the central theme of modern global development.With the arrival of the urban era,the vulnerability and instability of rural areas have significantly increased,and rural sustainable development faces serious challenges.To address these issues,the study took the Zaozhuang Innovation Demonstration Zone in China under the National Sustainable Development Agenda as a case,combined with economic,social and land use data during 2016-2020,and applied Granger causality test method to explore the theoretical and practical pathways of“innovation-driven rural sustainable development”.The results showed that rural sustainable development and economic sustainability displayed a trend of synergistic change,with“explosive”growth from 2018 to 2020.The social sustainability steadily increased from 2016 to 2020.Ecological and spatial sustainability continuously declined during the study period.Moreover,the rural innovation capacity of the Zaozhuang Innovation Demonstration Zone displayed rapid growth during 2016-2020.Although the rural innovation capacity of the Zaozhuang Innovation Demonstration Zone has rapidly improved,it has a weak driving effect on rural sustainable development and economic sustainability.There are two primary challenges that must be overcome to ensure the rural sustainable development of the Zaozhuang Innovation Demonstration Zone.The first challenge is the imbalance among the multi-dimensional relationships in the process of rural sustainable development,and the second challenge is the weakening of rural innovation capacity to drive rural sustainable development.To overcome these challenges,this study proposed a systematic pathway for rural sustainable development in the Zaozhuang Innovation Demonstration Zone from multidimensions,such as policy actions,technologies,projects,and institutional guarantees,and formed a universal and representative“Zaozhuang model”.This study expands the theoretical foundation of rural sustainable development and provides theoretical and practical support for innovation-driven rural sustainable development.展开更多
Objective:To determine the most common mistakes made during the use of a metered-dose inhaler(MDI),and the effect of the repeated trainings performed with demonstration method by providing one-to-one feedback on these...Objective:To determine the most common mistakes made during the use of a metered-dose inhaler(MDI),and the effect of the repeated trainings performed with demonstration method by providing one-to-one feedback on these mistakes.Methods:This is a quasi-experimental study with a control group.A total of 100 chronic obstructive pulmonary disease(COPD)patients(50 in the control group and 50 in the experimental group)were included in the research.“Patient Information Form(PIF)”(to determine the descriptive characteristics of patients)through the face-to-face interview method,using“MDI Skill Assessment Form”(MDISAF)(it is composed of 10 skill steps about the use of MDI)through observation method was used.Patients in both the groups were asked to use MDI and their abilities regarding use of MDI were assessed.Then in the intervention group,usage of MDI was explained by a nurse via demonstration and placebo MDI.Trainings were repeated on days 1,3,and 5 as from hospitalization of the patient.In the intervention group,three methods were used in this study:“face-to-face training,”“one-to-one,”and“with feedbacks and repeated.”Routine training regarding use of MDI was given by the nurses in the clinic to patients in the control group.The use of an MDI was assessed using MDISAF before training and after the training on the first,third and fifth days of hospitalization.On the seventh day,the last measurement was performed.Percentage,chi square,and mean were used to assess the data.Results:After repetitive training with one-to-one feedback,several differences between the groups in favor of the experimental group were found in 7 of the 10 skill levels of the MDI.There was a significant difference after“training”between the groups in the third,fourth,fifth,sixth,seventh,eighth and ninth MDI steps in posttest measurement(P<0.05).Evaluating the skills of the groups to use MDI from pretest to posttest,it was determined that while the intervention group made less mistakes in steps in which mistakes were made mostly,the control group continued to make mistakes.Conclusions:Inhaler technique intervention with repeated,face to face,and one-to-one feedback trainings can significantly enhance the MDI techniques in COPD patients.The patients in the intervention group made less mistakes during MDI application and their application skills improved.It may be asser ted that the training provided to the intervention group was effective for using the device correctly,while the training provided in the clinic for the control group was inadequate.展开更多
Agroforestry technologies are very keen practices in most small-scale farming systems where gender issues are not well considered in most developing countries.Moringa is a tropical plant that consists of 13 species,wh...Agroforestry technologies are very keen practices in most small-scale farming systems where gender issues are not well considered in most developing countries.Moringa is a tropical plant that consists of 13 species,while five of them are found in Ethiopia.This study aimed to evaluate the potential and contribution of women in agroforestry demonstrations where Moringa oleifera and Moringa stenopetala are introduced in farmers’fields.Selection of the best performing moringa species and preferred by farmers for further scaling up was also another objective.The activity was conducted in five districts of west and east Wallagga zones.A total of 10 FREG comprising 150 farmers were established.The two moringa species were planted on 100 farmers’fields where 50 women and 50 men were purposively selected and given responsibilities of moringa demonstration.Leaflets and practical training on moringa production,importance and utilization were prepared and given to all concerned bodies.84%of women and only 32%of men effectively demonstrated the moringa species.A total of 200 farmers were interviewed to evaluate and select the best from the two species depending on their growth performance,fresh leaf taste and odor,and survival rate.Based on the above criteria,143(71.5%)farmers preferred Moringa oleifera.In general,the two moringa species were performed well in most places,and its utilization started at household level.Finally,the authors recommend that women are the potential for demonstrating agroforestry technologies,and Moringa oleifera is a more preferred species in western Oromia.展开更多
Based on the research on the basic status quo of the construction of public employment and entrepreneurship service system in Daqing, this paper analyzes the problems existing in Daqing’s establishment of a national ...Based on the research on the basic status quo of the construction of public employment and entrepreneurship service system in Daqing, this paper analyzes the problems existing in Daqing’s establishment of a national public employment and entrepreneurship service demonstration city, and gives countermeasures and suggestions from three levels: optimizing the public employment and entrepreneurship service system, innovating the public employment and entrepreneurship service mode, and improving the entrepreneurship driven employment support system.展开更多
The comprehensive improvement strategy of intra-county environment pollution in the city and countryside was searched.By the research method which combined the microscopic view,the macroscopic view with the dynamic pe...The comprehensive improvement strategy of intra-county environment pollution in the city and countryside was searched.By the research method which combined the microscopic view,the macroscopic view with the dynamic perspective,the seriousness of rural water quality,soil and atmospheric pollution in Xiangxiang,Xiangtan and the surrounding areas in Shaoshan irrigated area was revealed.The control measure which was 'four-dimensional pollution in the city and countryside'—— low-carbon-high-value agriculture and the technology innovation was proposed.The low-carbon-high-value technology innovation industrialization demonstration in three parts which included the pre-production,mid-production and post-production deep-processing of cultivation and breeding industry in the ecological cyclic agricultural garden in Shaoshan irrigated area was the driving force.We tried to propel the low-carbon ecological cultivation and breeding industry which included the paddy rice,grass,tree,medicinal herbs and pig,cow,chick,duck,fish.We wanted to relieve the structural unbalance of previous cultivation and breeding industry,'cheap grain hurting the farmers' and the short-leg problem of social-economic-ecological benefit.The results showed that the low-carbon-high-value agricultural system was a poly-generation technology system which promoted the multi-level and grading utilization,saved the energy,reduced the consumption and cleaned the production based on the ecology.展开更多
With Xiangtian Village, Jin'an County as an example, development objec- tive and functional orientation of ecological and leisure agricultural demonstration park were described in detail, based on which a characteris...With Xiangtian Village, Jin'an County as an example, development objec- tive and functional orientation of ecological and leisure agricultural demonstration park were described in detail, based on which a characteristic and promising plan of the park was proposed.展开更多
Vocabulary teaching is one aspect of language teaching that has not been given the attention it deserves until recent years. For a long period of time, vocabulary is simply taught in the way by asking students to stud...Vocabulary teaching is one aspect of language teaching that has not been given the attention it deserves until recent years. For a long period of time, vocabulary is simply taught in the way by asking students to study and memorize its meaning and spelling, its part of speech and its general function in a sentence. Thus, a student with a command of five thousand English vocabulary still finds it hard to adapt himself to the requirement of our demanding reading assignments, in particular, to the extensive reading task, which is more demanding due to its wide range of materials and large amount of vocabularies. According to Wilkins (1979: 111) "Without grammar very little can be conveyed, without vocabulary, nothing can be conveyed." Yet without a deeper understanding of how vocabulary is taught in the classroom and which methods of teaching are more effective for learners, the teaching of vocabulary may not achieve the desired effects. By researching the topic on vocabulary learning and instruction, this essay intends to bring the attention of both teachers and learners to the weaknesses of the traditional approach of teaching vocabulary and some different strategies in vocabulary instruction with the aim of improving the students’ reading comprehension.\;展开更多
In order to resolve the issue of soil erosion in East African plateau, a micro-landscape irrigation region was established in Ethiopia plateau to research status quo of agricultural demonstration site in Jari in Ethio...In order to resolve the issue of soil erosion in East African plateau, a micro-landscape irrigation region was established in Ethiopia plateau to research status quo of agricultural demonstration site in Jari in Ethiopia and to analyze the relation between structure and function of inner elements in different landscapes of demonstration site. Furthermore, in accordance with ecology, silviculture, agriculture and economics, the ecological landscapes were classified as per landscape functions; lands returning from farming were classified and re-used; ecosystems of grassland, river, agriculture and courtyard were researched; the feasibility of ecological restoration and sustainable development in demonstration site was demonstrated; the model for rational irrigation and water conservation was proposed. The research guarantees sustainable development of agriculture and animal husbandry and provides references for undeveloped countries with similar problems.展开更多
文摘The main idea of reinforcement learning is evaluating the chosen action depending on the current reward.According to this concept,many algorithms achieved proper performance on classic Atari 2600 games.The main challenge is when the reward is sparse or missing.Such environments are complex exploration environments likeMontezuma’s Revenge,Pitfall,and Private Eye games.Approaches built to deal with such challenges were very demanding.This work introduced a different reward system that enables the simple classical algorithm to learn fast and achieve high performance in hard exploration environments.Moreover,we added some simple enhancements to several hyperparameters,such as the number of actions and the sampling ratio that helped improve performance.We include the extra reward within the human demonstrations.After that,we used Prioritized Double Deep Q-Networks(Prioritized DDQN)to learning from these demonstrations.Our approach enabled the Prioritized DDQNwith a short learning time to finish the first level of Montezuma’s Revenge game and to perform well in both Pitfall and Private Eye.We used the same games to compare our results with several baselines,such as the Rainbow and Deep Q-learning from demonstrations(DQfD)algorithm.The results showed that the new rewards system enabled Prioritized DDQN to out-perform the baselines in the hard exploration games with short learning time.
基金National Natural Science Foundation of China(NSFC)(61377081,61675126)
文摘In this paper, a detailed theoretical study on the characteristics of cone-shaped inwall capillary-based microsphere resonators is described and demonstrated for sensing applications. The maximum, minimum, slope, contrast, and width of the Fano resonance are analyzed. As the transmission coefficient of the capillary resonator increases, the absolute value of the slope of Fano resonances increases to reach its maximum, which is useful for sensors with an ultra-high sensitivity. There occurs another phenomenon of electromagnetically induced transparency when the reflectivity at the capillary–environment interface is close to 100%. We also experimentally demonstrated its capability for temperature and refractive index sensing, with a sensitivity of 10.9 pm∕°C and 431 d B∕RIU basedon the Fano resonance and the Lorentzian line shape, respectively.
基金the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.51521003)the National Natural Science Foundation of China(Grant No.61803124)the Post-doctor Research Startup Foundation of Heilongjiang Province。
文摘Autonomous planning is a significant development direction of the space manipulator,and learning from demonstrations(LfD)is a potential strategy for complex tasks in the field.However,separating control from planning may cause large torque fluctuations and energy consumptions,even instability or danger in control of space manipulators,especially for the planning based on the human demonstrations.Therefore,we present an autonomous planning and control strategy for space manipulators based on LfD and focus on the dynamics uncertainty problem,a common problem of actual manipulators.The process can be divided into three stages:firstly,we reproduced the stochastic directed trajectory based on the Gaussian process-based LfD;secondly,we built the model of the stochastic dynamics of the actual manipulator with Gaussian process;thirdly,we designed an optimal controller based on the dynamics model to obtain the improved commanded torques and trajectory,and used the separation theorem to deal with stochastic characteristics during control.We evaluated the strategy with locating pre-screwed bolts experiment by Tiangong-2 manipulator system on the ground.The result showed that,compared with other strategies,the strategy proposed in this paper could significantly reduce torque fluctuations and energy consumptions,and its precision can meet the task requirements.
基金supported by the National Natural Science Foundation of China[Grant No.72163018]the Yunnan College Students’Innovation and Entrepreneurship Training Program[Grant No.S202310674173]the Yunnan Province Basic Research Program General Project[Grant No.202401AT070393].
文摘The national independent innovation demonstration zone(NIIDZ)is an independent innovation policy that plays a crucial role in implementing strategies.Given the importance of the NIIDZ,this study uses panel data of 278 prefecture-level cities in China from 2006 to 2020 and empirically examines the effect and internal mechanism of the NIIDZ on green economic efficiency(GEE)using the difference-in-difference model(DID).The results show that the NIIDZ effectively enhances the growth of GEE,and the results remain valid through several robustness tests,such as year-by-year propensity score matching.The transmission mechanism suggests that the NIIDZ indirectly drives GEE by accelerating scientific and technological investment,promoting talent concentration,and optimizing the industrial structure.Moreover,heterogeneity analysis reveals that the promotion effect of the NIIDZ on GEE is more prominent in the eastern region and high green development level areas.The study’s findings can serve as a reference for China to further utilize the policy effectiveness of the NIIDZ and accelerate the high-quality development of the green economy in the future.
基金Sponsored by the Achievements of Social Science Planning Research Project of Shandong Province(22CYMJ11)Phased Achievements of the key project of the Party School of Shandong Provincial Committee of the Communist Party of China(Shandong Administration College).
文摘Yimeng red culture is an important part of the excellent culture of the Chinese nation.It is of great practical significance and long-term strategic significance to build the demonstration area for the inheritance and development of Yimeng red culture.Combining digital empowerment with the inheritance and development of Yimeng red culture is a new idea that conforms to the development of the times.In this paper,on the basis of combing Yimeng red cultural resources and combining with the current situation of inheritance and development of Yimeng red culture,the strategic layout and implementation approach of the demonstration area for the inheritance and development of Yimeng red culture were put forward from the perspective of digital empowerment.
文摘Considering Pythagorician divisors theory which leads to a new parameterization, for Pythagorician triplets ( a,b,c )∈ ℕ 3∗ , we give a new proof of the well-known problem of these particular squareless numbers n∈ ℕ ∗ , called congruent numbers, characterized by the fact that there exists a right-angled triangle with rational sides: ( A α ) 2 + ( B β ) 2 = ( C γ ) 2 , such that its area Δ= 1 2 A α B β =n;or in an equivalent way, to that of the existence of numbers U 2 , V 2 , W 2 ∈ ℚ 2∗ that are in an arithmetic progression of reason n;Problem equivalent to the existence of: ( a,b,c )∈ ℕ 3∗ prime in pairs, and f∈ ℕ ∗ , such that: ( a−b 2f ) 2 , ( c 2f ) 2 , ( a+b 2f ) 2 are in an arithmetic progression of reason n;And this problem is also equivalent to that of the existence of a non-trivial primitive integer right-angled triangle: a 2 + b 2 = c 2 , such that its area Δ= 1 2 ab=n f 2 , where f∈ ℕ ∗ , and this last equation can be written as follows, when using Pythagorician divisors: (1) Δ= 1 2 ab= 2 S−1 d e ¯ ( d+ 2 S−1 e ¯ )( d+ 2 S e ¯ )=n f 2;Where ( d, e ¯ )∈ ( 2ℕ+1 ) 2 such that gcd( d, e ¯ )=1 and S∈ ℕ ∗ , where 2 S−1 , d, e ¯ , d+ 2 S−1 e ¯ , d+ 2 S e ¯ , are pairwise prime quantities (these parameters are coming from Pythagorician divisors). When n=1 , it is the case of the famous impossible problem of the integer right-angled triangle area to be a square, solved by Fermat at his time, by his famous method of infinite descent. We propose in this article a new direct proof for the numbers n=1 (resp. n=2 ) to be non-congruent numbers, based on an particular induction method of resolution of Equation (1) (note that this method is efficient too for general case of prime numbers n=p≡a ( ( mod8 ) , gcd( a,8 )=1 ). To prove it, we use a classical proof by induction on k , that shows the non-solvability property of any of the following systems ( t=0 , corresponding to case n=1 (resp. t=1 , corresponding to case n=2 )): ( Ξ t,k ){ X 2 + 2 t ( 2 k Y ) 2 = Z 2 X 2 + 2 t+1 ( 2 k Y ) 2 = T 2 , where k∈ℕ;and solutions ( X,Y,Z,T )=( D k , E k , f k , f ′ k )∈ ( 2ℕ+1 ) 4 , are given in pairwise prime numbers.2020-Mathematics Subject Classification 11A05-11A07-11A41-11A51-11D09-11D25-11D41-11D72-11D79-11E25 .
基金This work was supported by the National Key R&D Plan(2016YFB0100901)the National Natural Science Foundation of China(Grant Nos.U20B2062&61673237)the Beijing Municipal Science&Technology Project(Z191100007419001).
文摘In actor-critic reinforcement learning(RL)algorithms,function estimation errors are known to cause ineffective random exploration at the beginning of training,and lead to overestimated value estimates and suboptimal policies.In this paper,we address the problem by executing advantage rectification with imperfect demonstrations,thus reducing the function estimation errors.Pretraining with expert demonstrations has been widely adopted to accelerate the learning process of deep reinforcement learning when simulations are expensive to obtain.However,existing methods,such as behavior cloning,often assume the demonstrations contain other information or labels with regard to performances,such as optimal assumption,which is usually incorrect and useless in the real world.In this paper,we explicitly handle imperfect demonstrations within the actor-critic RL frameworks,and propose a new method called learning from imperfect demonstrations with advantage rectification(LIDAR).LIDAR utilizes a rectified loss function to merely learn from selective demonstrations,which is derived from a minimal assumption that the demonstrating policies have better performances than our current policy.LIDAR learns from contradictions caused by estimation errors,and in turn reduces estimation errors.We apply LIDAR to three popular actor-critic algorithms,DDPG,TD3 and SAC,and experiments show that our method can observably reduce the function estimation errors,effectively leverage demonstrations far from the optimal,and outperform state-of-the-art baselines consistently in all the scenarios.
文摘Burundi and China enjoy close collaboration in a number of sectors,particularly agriculture.Among the major initiatives,the introduction of hybrid rice cultivation stands out as a flagship project.In 2018,the first demonstration village for hybrid rice cultivation was established in the commune of Gihanga in northwestern Burundi.In 2020,this initiative reached a crucial stage with the creation of the Burundi Agricultural Pilot Centre(APC),located in Gihanga in the province of Bubanza.A total of 56 villages spread across 11 of Burundi’s 18 provinces have been selected for demonstration as of now.Yang Huade,head of the team of high-level Chinese agricultural experts supporting Burundi and a rice cultivation specialist who is also in charge of the APC,revealed that trials are currently underway in four provinces:the capital Gitega,the central province of Muramvya,and the northern provinces of Ngozi and Kayanza.
文摘With the rapid development of industrialisation and urbanisation, China is facing the challenge of severe HF (Haze-Fog) pollution. This essay compares the advantages and disadvantages of China’s HF management and summarizes the important lessons China can teach the rest of the world about applying this tactic. China’s capabilities in the digital economy, National Innovation Demonstration Zones, and urban innovation systems are examined in this article, along with its shortcomings in information mechanisms and pollution sources. This essay also summarizes China’s achievements, particularly regarding local autonomy. The essay goes on to say, however, that China is probably going to be under more pressure to manage HF in the future, both in terms of long-term solutions and the economy.
文摘Taking the National Experimental Teaching Demonstration Center of the Central Academy of Drama as an example,this article explores the construction and development of the National Experimental Teaching Demonstration Center for the practical teaching of drama and film and television disciplines.The article first introduces the background and importance of the demonstration center and then analyzes in depth the construction content and achievements of the demonstration center from four aspects:practical teaching philosophy,practical teaching system,practical teaching resources,and practical teaching effects.Finally,the article summarizes the experience and shortcomings of the demonstration center and proposes future development directions and suggestions.
基金supported in part by the"Juan de la Cierva"Spanish Program
文摘In this paper, we propose a new prediction from expert demonstration (PED) methodology to improve reliability and safety in tele-surgery. Data was collected from expert (clinician) demonstrations for the procedure of trocar insertion. We encoded a set of force, torque and penetration trajectories by using a Gaussian mixture model (GMM). A generalization of these profiles and associated parameters were retrieved by Gaussian mixture regression (GMR). We validated the proposed methodology for tele-robotic placement of the trocar in two stages. First, we tested the efficacy of the proposed PED approach for handling transmission error and latency. Our results showed that for the average case (12% packet error and 1070 loss of packet), a 58.8~0 improvement in performance was obtained in comparison to using an extended Kalman filter. Next, we validated the methodology for surgical assistance on 15 participants. A haptic assistance mode was devised based on the proposed PED model to assist inexperienced operators to perform the procedure. The PED model was tested for instrument deviation, penetration force and penetration depth. Preliminary study results showed that participants with PED assistance performed the task with more consistency and exerted lesser penetration force than subjects without assistance.
基金All authors are partially supported by the Wallenberg AI,Autonomous Systems and Software Program(WASP)funded by the Knut and Alice Wallenberg Foundation.The first and second authors are additionally supported by the ELLIIT Network Organization for Information and Communication Technology,Swedenthe Swedish Foundation for Strategic Research SSF(Smart Systems Project RIT15-0097)+1 种基金The second author is also supported by a RExperts Program Grant 2020A1313030098 from the Guangdong Department of Science and Technology,ChinaThe fifth and eighth authors are additionally supported by the Swedish Research Council.
文摘A research arena(WARA-PS)for sensing,data fusion,user interaction,planning and control of collaborative autonomous aerial and surface vehicles in public safety applications is presented.The objective is to demonstrate scientific discoveries and to generate new directions for future research on autonomous systems for societal challenges.The enabler is a computational infrastructure with a core system architecture for industrial and academic collaboration.This includes a control and command system together with a framework for planning and executing tasks for unmanned surface vehicles and aerial vehicles.The motivating application for the demonstration is marine search and rescue operations.A state-of-art delegation framework for the mission planning together with three specific applications is also presented.The first one concerns model predictive control for cooperative rendezvous of autonomous unmanned aerial and surface vehicles.The second project is about learning to make safe real-time decisions under uncertainty for autonomous vehicles,and the third one is on robust terrain-aided navigation through sensor fusion and virtual reality tele-operation to support a GPS-free positioning system in marine environments.The research results have been experimentally evaluated and demonstrated to industry and public sector audiences at a marine test facility.It would be most difficult to do experiments on this large scale without the WARA-PS research arena.Furthermore,these demonstrator activities have resulted in effective research dissemination with high public visibility,business impact and new research collaborations between academia and industry.
基金funded by the National Natural Science Foundation of China(72134002,42101264)the Fundamental Research Funds for the Central Universities(2023CDSKXYGG006)+3 种基金the Key Projects of Philosophy and Social Sciences Research,Ministry of Education of China(21JZD029)the Department of Science and Technology for Social Development of Ministry of Science and Technology of Chinathe Administrative Center for China’s Agenda 21the Zaozhuang Science and Technology Bureau for their support。
文摘Sustainable development is the central theme of modern global development.With the arrival of the urban era,the vulnerability and instability of rural areas have significantly increased,and rural sustainable development faces serious challenges.To address these issues,the study took the Zaozhuang Innovation Demonstration Zone in China under the National Sustainable Development Agenda as a case,combined with economic,social and land use data during 2016-2020,and applied Granger causality test method to explore the theoretical and practical pathways of“innovation-driven rural sustainable development”.The results showed that rural sustainable development and economic sustainability displayed a trend of synergistic change,with“explosive”growth from 2018 to 2020.The social sustainability steadily increased from 2016 to 2020.Ecological and spatial sustainability continuously declined during the study period.Moreover,the rural innovation capacity of the Zaozhuang Innovation Demonstration Zone displayed rapid growth during 2016-2020.Although the rural innovation capacity of the Zaozhuang Innovation Demonstration Zone has rapidly improved,it has a weak driving effect on rural sustainable development and economic sustainability.There are two primary challenges that must be overcome to ensure the rural sustainable development of the Zaozhuang Innovation Demonstration Zone.The first challenge is the imbalance among the multi-dimensional relationships in the process of rural sustainable development,and the second challenge is the weakening of rural innovation capacity to drive rural sustainable development.To overcome these challenges,this study proposed a systematic pathway for rural sustainable development in the Zaozhuang Innovation Demonstration Zone from multidimensions,such as policy actions,technologies,projects,and institutional guarantees,and formed a universal and representative“Zaozhuang model”.This study expands the theoretical foundation of rural sustainable development and provides theoretical and practical support for innovation-driven rural sustainable development.
文摘Objective:To determine the most common mistakes made during the use of a metered-dose inhaler(MDI),and the effect of the repeated trainings performed with demonstration method by providing one-to-one feedback on these mistakes.Methods:This is a quasi-experimental study with a control group.A total of 100 chronic obstructive pulmonary disease(COPD)patients(50 in the control group and 50 in the experimental group)were included in the research.“Patient Information Form(PIF)”(to determine the descriptive characteristics of patients)through the face-to-face interview method,using“MDI Skill Assessment Form”(MDISAF)(it is composed of 10 skill steps about the use of MDI)through observation method was used.Patients in both the groups were asked to use MDI and their abilities regarding use of MDI were assessed.Then in the intervention group,usage of MDI was explained by a nurse via demonstration and placebo MDI.Trainings were repeated on days 1,3,and 5 as from hospitalization of the patient.In the intervention group,three methods were used in this study:“face-to-face training,”“one-to-one,”and“with feedbacks and repeated.”Routine training regarding use of MDI was given by the nurses in the clinic to patients in the control group.The use of an MDI was assessed using MDISAF before training and after the training on the first,third and fifth days of hospitalization.On the seventh day,the last measurement was performed.Percentage,chi square,and mean were used to assess the data.Results:After repetitive training with one-to-one feedback,several differences between the groups in favor of the experimental group were found in 7 of the 10 skill levels of the MDI.There was a significant difference after“training”between the groups in the third,fourth,fifth,sixth,seventh,eighth and ninth MDI steps in posttest measurement(P<0.05).Evaluating the skills of the groups to use MDI from pretest to posttest,it was determined that while the intervention group made less mistakes in steps in which mistakes were made mostly,the control group continued to make mistakes.Conclusions:Inhaler technique intervention with repeated,face to face,and one-to-one feedback trainings can significantly enhance the MDI techniques in COPD patients.The patients in the intervention group made less mistakes during MDI application and their application skills improved.It may be asser ted that the training provided to the intervention group was effective for using the device correctly,while the training provided in the clinic for the control group was inadequate.
文摘Agroforestry technologies are very keen practices in most small-scale farming systems where gender issues are not well considered in most developing countries.Moringa is a tropical plant that consists of 13 species,while five of them are found in Ethiopia.This study aimed to evaluate the potential and contribution of women in agroforestry demonstrations where Moringa oleifera and Moringa stenopetala are introduced in farmers’fields.Selection of the best performing moringa species and preferred by farmers for further scaling up was also another objective.The activity was conducted in five districts of west and east Wallagga zones.A total of 10 FREG comprising 150 farmers were established.The two moringa species were planted on 100 farmers’fields where 50 women and 50 men were purposively selected and given responsibilities of moringa demonstration.Leaflets and practical training on moringa production,importance and utilization were prepared and given to all concerned bodies.84%of women and only 32%of men effectively demonstrated the moringa species.A total of 200 farmers were interviewed to evaluate and select the best from the two species depending on their growth performance,fresh leaf taste and odor,and survival rate.Based on the above criteria,143(71.5%)farmers preferred Moringa oleifera.In general,the two moringa species were performed well in most places,and its utilization started at household level.Finally,the authors recommend that women are the potential for demonstrating agroforestry technologies,and Moringa oleifera is a more preferred species in western Oromia.
文摘Based on the research on the basic status quo of the construction of public employment and entrepreneurship service system in Daqing, this paper analyzes the problems existing in Daqing’s establishment of a national public employment and entrepreneurship service demonstration city, and gives countermeasures and suggestions from three levels: optimizing the public employment and entrepreneurship service system, innovating the public employment and entrepreneurship service mode, and improving the entrepreneurship driven employment support system.
基金Supported by " Research on The Control Technology of Subtropical Agriculture Pollution System" Special Project of National Environment Protection Public Welfare Industry Science Research "Research on The Construction Strategy of Ecological Civilization" Development Plan Research Project of State Development and Reform Commission+1 种基金Xiangxiang " High-output and Efficient Cultivation of High Quality Rice and Processing Technology Industrialization Demonstration " in The Plan Test Site of National Science and Technology Enriching People and Developing County Special Project Action" Xiangxiang Middle and Long-term Development Plan of Modern Agriculture" of Subtropical Agriculture Ecology Institute in Chinese Academy of Science
文摘The comprehensive improvement strategy of intra-county environment pollution in the city and countryside was searched.By the research method which combined the microscopic view,the macroscopic view with the dynamic perspective,the seriousness of rural water quality,soil and atmospheric pollution in Xiangxiang,Xiangtan and the surrounding areas in Shaoshan irrigated area was revealed.The control measure which was 'four-dimensional pollution in the city and countryside'—— low-carbon-high-value agriculture and the technology innovation was proposed.The low-carbon-high-value technology innovation industrialization demonstration in three parts which included the pre-production,mid-production and post-production deep-processing of cultivation and breeding industry in the ecological cyclic agricultural garden in Shaoshan irrigated area was the driving force.We tried to propel the low-carbon ecological cultivation and breeding industry which included the paddy rice,grass,tree,medicinal herbs and pig,cow,chick,duck,fish.We wanted to relieve the structural unbalance of previous cultivation and breeding industry,'cheap grain hurting the farmers' and the short-leg problem of social-economic-ecological benefit.The results showed that the low-carbon-high-value agricultural system was a poly-generation technology system which promoted the multi-level and grading utilization,saved the energy,reduced the consumption and cleaned the production based on the ecology.
文摘With Xiangtian Village, Jin'an County as an example, development objec- tive and functional orientation of ecological and leisure agricultural demonstration park were described in detail, based on which a characteristic and promising plan of the park was proposed.
文摘Vocabulary teaching is one aspect of language teaching that has not been given the attention it deserves until recent years. For a long period of time, vocabulary is simply taught in the way by asking students to study and memorize its meaning and spelling, its part of speech and its general function in a sentence. Thus, a student with a command of five thousand English vocabulary still finds it hard to adapt himself to the requirement of our demanding reading assignments, in particular, to the extensive reading task, which is more demanding due to its wide range of materials and large amount of vocabularies. According to Wilkins (1979: 111) "Without grammar very little can be conveyed, without vocabulary, nothing can be conveyed." Yet without a deeper understanding of how vocabulary is taught in the classroom and which methods of teaching are more effective for learners, the teaching of vocabulary may not achieve the desired effects. By researching the topic on vocabulary learning and instruction, this essay intends to bring the attention of both teachers and learners to the weaknesses of the traditional approach of teaching vocabulary and some different strategies in vocabulary instruction with the aim of improving the students’ reading comprehension.\;
基金Supported by South-South Cooperation Project of SSC/SPFS-FAO-Ethiopia-China~~
文摘In order to resolve the issue of soil erosion in East African plateau, a micro-landscape irrigation region was established in Ethiopia plateau to research status quo of agricultural demonstration site in Jari in Ethiopia and to analyze the relation between structure and function of inner elements in different landscapes of demonstration site. Furthermore, in accordance with ecology, silviculture, agriculture and economics, the ecological landscapes were classified as per landscape functions; lands returning from farming were classified and re-used; ecosystems of grassland, river, agriculture and courtyard were researched; the feasibility of ecological restoration and sustainable development in demonstration site was demonstrated; the model for rational irrigation and water conservation was proposed. The research guarantees sustainable development of agriculture and animal husbandry and provides references for undeveloped countries with similar problems.