Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochast...Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochastic models is not well understood.The present study aimed to address this gap by conducting a comparative study using the susceptible,exposed,infectious,and recovered(SEIR)model and its extended CMs from the coronavirus disease 2019 modeling literature.We demonstrated the equivalence of the numerical solution of CMs using the Euler scheme and their stochastic counterparts through theoretical analysis and simulations.Based on this equivalence,we proposed an efficient model calibration method that could replicate the exact solution of CMs in the corresponding stochastic models through parameter adjustment.The advancement in calibration techniques enhanced the accuracy of stochastic modeling in capturing the dynamics of epidemics.However,it should be noted that discrete-time stochastic models cannot perfectly reproduce the exact solution of continuous-time CMs.Additionally,we proposed a new stochastic compartment and agent mixed model as an alternative to agent-based models for large-scale population simulations with a limited number of agents.This model offered a balance between computational efficiency and accuracy.The results of this research contributed to the comparison and unification of deterministic CMs and stochastic models in epidemic modeling.Furthermore,the results had implications for the development of hybrid models that integrated the strengths of both frameworks.Overall,the present study has provided valuable epidemic modeling techniques and their practical applications for understanding and controlling the spread of infectious diseases.展开更多
In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any mod...In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any modern company. A companys operational and historical data contains strategic and operational knowledge of ever-increasing added value. The emergence of a new paradigm: big data. Today, the value of the data scattered throughout this mother of knowledge is calculated in billions of dollars, depending on its size, scope and area of intervention. With the rise of computer networks and distributed systems, the threats to these sensitive resources have steadily increased, jeopardizing the existence of the company itself by drying up production and losing the interest of customers and suppliers. These threats range from sabotage to bankruptcy. For several decades now, most companies have been using encryption algorithms to protect and secure their information systems against the threats and dangers posed by the inherent vulnerabilities of their infrastructure and the current economic climate. This vulnerability requires companies to make the right choice of algorithms to implement in their management systems. For this reason, the present work aims to carry out a comparative study of the reliability and effectiveness of symmetrical and asymmetrical cryptosystems, in order to identify one or more suitable for securing academic data in the DRC. The analysis of the robustness of commonly used symmetric and asymmetric cryptosystems will be the subject of simulations in this article.展开更多
Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their perform...Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their performance is exploited with lossy compression techniques for images and videos generally using a mixed approach. To achieve our intended objective, which is to study the performance of lossless compression methods, we first carried out a literature review, a summary of which enabled us to select the most relevant, namely the following: arithmetic coding, LZW, Tunstall’s algorithm, RLE, BWT, Huffman coding and Shannon-Fano. Secondly, we designed a purposive text dataset with a repeating pattern in order to test the behavior and effectiveness of the selected compression techniques. Thirdly, we designed the compression algorithms and developed the programs (scripts) in Matlab in order to test their performance. Finally, following the tests conducted on relevant data that we constructed according to a deliberate model, the results show that these methods presented in order of performance are very satisfactory:- LZW- Arithmetic coding- Tunstall algorithm- BWT + RLELikewise, it appears that on the one hand, the performance of certain techniques relative to others is strongly linked to the sequencing and/or recurrence of symbols that make up the message, and on the other hand, to the cumulative time of encoding and decoding.展开更多
Due to the integrated development between Chengdu and Chongqing,there are a large number of residents flowing into the two cities from their surrounding areas,so community renewal is imminent.Because of the similarity...Due to the integrated development between Chengdu and Chongqing,there are a large number of residents flowing into the two cities from their surrounding areas,so community renewal is imminent.Because of the similarity in the historical and cultural background of the two places,a comparative analysis of the evolution of community space in Chengdu-Chongqing Region enables Chengdu and Chongqing learn from each other and speed up the pace of renewal.This paper analyzed the evolution of community space in main urban areas of Chengdu and Chongqing.Specifically,the evolution of community space in Chengdu and Chongqing went through three stages.The starting time of community renewal in the two places was very close,but the duration of each stage varied.The second stage of Chengdu continued for a longer time,so its renovation and renewal of the community space was more detailed and thorough,and the emphasis and extension direction of the evolution of the community space were different.The evolution of community space in both Chengdu and Chongqing went through"mechanical renewal of demolition and construction—small-scale gradual renewal",but the path of renewal and development of the community space in Chengdu was faster.This paper,from the perspective of the evolution of community space,put forward the framework and content of community renewal in Chengdu and Chongqing based on community development and elaborated the community research content based on community development.展开更多
[Objective] In order to identify and comparatively study leaves of ethnic medicine Gaultheria yunnanensis from different regions of Guizhou.[Method] Characteristics,microscopic,physical and chemical identification wer...[Objective] In order to identify and comparatively study leaves of ethnic medicine Gaultheria yunnanensis from different regions of Guizhou.[Method] Characteristics,microscopic,physical and chemical identification were studied on Gaultheria yunnanensis.[Result] There was no obvious difference in characteristics and microscopic sections among Gaultheria yunnanensis leaves from different regions.Blue fluorescence spots were observed clearly by TLC(Thin Layer Chromatography) test.[Conclusion]The study provided a basis for improvement of the quality standard of the Gaultheria yunnanensis.展开更多
Both metonymy and metaphor are very important in our cognitive activities, but there are some distinctions and common grounds between them. This paper mainly deals with in what way they distinct in some aspects, while...Both metonymy and metaphor are very important in our cognitive activities, but there are some distinctions and common grounds between them. This paper mainly deals with in what way they distinct in some aspects, while how they are related to each other in other aspects.展开更多
By introducing the analytic hierarchy process (AHP), a model is constructed to compare the logistics development level of cold chain for agricultural products between China and other developed countries such as Unit...By introducing the analytic hierarchy process (AHP), a model is constructed to compare the logistics development level of cold chain for agricultural products between China and other developed countries such as United States, Japan and Euro- pean. The paper makes a comparative study on the development levels of agricultural cold chain logistics in China and developed countries from the aspects of the level of cold chain logistics facilities and equipments, the degree of cold chain logistics market-oriented and the capacity of cold chain logistics, then determines the problems of cold chain logistics in China. With the experiences learning from developed countries, some countermeasures are proposed to resolve those problems of cold chain logistics for agricultural products development combining with the national conditions in China.展开更多
Simile, as a kind of commonly used rhetoric, plays a vital role in people's daily life. The appropriate using of simile can make language much more refine, veracious, and lifelike, can vividly present the person, the...Simile, as a kind of commonly used rhetoric, plays a vital role in people's daily life. The appropriate using of simile can make language much more refine, veracious, and lifelike, can vividly present the person, the thing, the scene and so on to achieve better effects. Simile makes the finishing point in Chinese and English. However, because of the differences on culture, history, geography, customs, expressing ways and so on, there are some structural differences between Chinese and English simile. This paper will carry out the comparative study on the structure of Chinese and English simile.展开更多
The aim of the paper is to give a general comparison about the structural composition of the AUX in English and Chinese mainly from the perspective of tense-aspect.Based on the basic construction of English AUX system...The aim of the paper is to give a general comparison about the structural composition of the AUX in English and Chinese mainly from the perspective of tense-aspect.Based on the basic construction of English AUX system,which includes such elements as Tense,Modal,Perfect aspect,Progressive aspect and Passive,the paper focuses on comparing the syntactic characteristics of tense element in the two languages.The final part of the paper briefly summarized predicted learning problems that Chinese learners of English as well as English learners of Chinese would have in learning English and Chinese respectively.展开更多
Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of ...Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of abstracts from a macro perspective and often employed either outdated texts,such as those over a decade old,or papers written by authors with lower English academic writing proficiency as research material.In this study,we analyzed forty abstracts from leading journals in applied linguistics,evenly split between Chinese and international journals.It revealed that the use of nominalization in abstracts by Chinese and international scholars showed similarities due to the universal academic requirement for conciseness.However,due to cultural and educational differences,each group differed in their respective language choices and nominalization usage.By analyzing the application of nominalization in different cultural contexts,the results of our study offered practical suggestions for crafting abstracts that effectively convey information,thereby,contributing to the broader academic community.展开更多
In its new development stage,China seeks to derive new dynamism from reform and opening up at a higher level to boost consumption and services.This process coincides with a further differentiation of comparative advan...In its new development stage,China seeks to derive new dynamism from reform and opening up at a higher level to boost consumption and services.This process coincides with a further differentiation of comparative advantages across regions.Economic activity and population will continue to concentrate in clusters in coastal and central cities amid a continuous outflow of population from remote areas.Development expansion from coastal to interior regions and from central cities to the periphery will promote a new regional development paradigm of“dual centers and periphery”.Therefore,China’s regional development strategy should follow the new theory of seeking relative equilibrium amid development,identify regions of population inflow and outflow,and explore a new development path of regional specialization and coordination.By deepening market reforms and increasing central government coordination,the country is poised to improve the spatial allocation of resources and unleash institutional dividends in the process of developing a unified national market.展开更多
This paper analyzes and compares the key factors influencing food security in two populous countries(China and India),and cate-gorizes them into three types:agricultural production,economic development and income leve...This paper analyzes and compares the key factors influencing food security in two populous countries(China and India),and cate-gorizes them into three types:agricultural production,economic development and income level,and income distribution.Using the prevalence of undernourishment as an indicator of food security,the paper empirically tests the degree of impact of various factors on food security in both countries using Tobit regression and Newey regression methods.The study finds that improving the level of economic development can significantly enhance food security in both countriesꎻreducing the Gini coefficient has a significant impact on India,but not on Chinaꎻincreasing the agricultural production per capita has a much greater effect on China than on India.Therefore,both countries should take measures that are both similar and different according to their national conditions to improve their food security level.展开更多
A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system(HFACS) and the accident causation "2-4" model(2...A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system(HFACS) and the accident causation "2-4" model(24 Model), as well as to provide a reference for safety researchers and accident investigators to select an appropriate accident analysis method. The two models are compared in terms of their theoretical foundations, cause classifications, accident analysis processes, application ranges, and accident prevention strategies. A coal and gas outburst accident is then analyzed using both models, and the application results are compared. This study shows that both the 24 Model and HFACS have strong theoretical foundations, and they can each be applied in various domains. In addition, the cause classification in HFACS is more practical, and its accident analysis process is more convenient. On the other hand, the 24 Model includes external factors, which makes the cause analysis more systematic and comprehensive. Moreover, the 24 Model puts forward more corresponding measures to prevent accidents.展开更多
City park, as an everlasting cultural carrier, is an important place for the expression of regional culture. The concept and characteristics of regional culture are summarized, and regional culture inheritance carrier...City park, as an everlasting cultural carrier, is an important place for the expression of regional culture. The concept and characteristics of regional culture are summarized, and regional culture inheritance carrier mainly includes land, garden style, garden building, etc. There are generally six methods: reservation, restoration, inheritance and development, extraction, reappearance, and creation. Taking Fule mountain Park in Mianyang City for example, combination of regional culture and landscape is analyzed.展开更多
Determining the main controlling factors of earthquake-triggered geohazards is a prerequisite for studying earthquake geohazards and post-disaster emergency response.By studying these factors,the geomorphic and geolog...Determining the main controlling factors of earthquake-triggered geohazards is a prerequisite for studying earthquake geohazards and post-disaster emergency response.By studying these factors,the geomorphic and geological factors controlling the nature,condition,and distribution of earthquake-induced geohazards can be analyzed.Such insights facilitate earthquake disaster prediction and emergency response planning.The authors combined field investigations and spatial data analysis to examine geohazards induced by seismic events,examining ten earthquakes including the Wenchuan,Yushu,Lushan events,to elucidate the main control factors of seismic geohazard.The authors observed that seismic geohazard occurrence is usually affected by many factors,among which active nature of the seismogenic fault,seismic peak ground acceleration(PGA),topographic slope and geomorphic height differences,and distance from the fault zone and river system are the most important.Compared with strike-slip earthquakes,thrust earthquakes induce more high-altitude and high-speed remote landslides,which can cause great harm.Slopes of 0°–40°are prone to secondary seismic geohazards,which are mainly concentrated 0–6 km from the river system.Secondary geohazards are not only related to seismogenic fault but also influenced by the associated faults in the earthquake area.The maximum seismic PGA and secondary seismic geohazard number are positively correlated,and the horizontal and vertical ground motions play leading and promoting roles in secondary geohazard formation,respectively.Through the research,the spatial distribution of seismic geohazards is predicted,providing a basis for the formulation of emergency response plans following disasters.展开更多
The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy p...The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy parameterization-building energy model (UCP- BEM) urban physics scheme. The experiments were designed with a focus on the influence of different urban intensities, which are represented by a different fractional coverage of natural land, buildings, and energy consumption inside buildings in an urban environment. The results of this study indicate that urban areas notably influence fog evolution when natural land is reduced to a small fraction (e.g., less than 10%). Developed land changes fog evolution through urban effects. Higher urban intensity (HUI) generally results in warmer temperatures and lower wind speeds throughout the day, while inhibiting morning specific humidity loss and afternoon specific humidity gain because of the HUI effect on surface heat flux, surface roughness, and surface moisture flux. HUI leads to later and weaker liquid water content formation, with a higher liquid water content base, primarily due to its effect on near surface temperatures. This finding implies that HUI may inhibit the conditions for fog formation. In addition, urban areas with equal natural and developed land coverage seem to greatly enhance the upward surface moisture flux, which is attributed to the combination of a relatively large potential evaporation on developed land and an ample moisture supply from natural land. As a result, the specific humidity increases in the afternoon.展开更多
The purpose of this study is to address the problem of ancient towns dying out in developing countries,particularly China.Intensifying conflicts between human settlements and the natural environment are described,and ...The purpose of this study is to address the problem of ancient towns dying out in developing countries,particularly China.Intensifying conflicts between human settlements and the natural environment are described,and guidelines are proposed for the development of waterside ancient towns in China’s southern Shaanxi Province in the interest of conserving cultural and natural heritage.The towns of Qingmuchuan,Fenghuang and Houliu were selected as representative examples due to their strong reputation among tourists.They have the characteristics of traditional southern Shaanxi towns,but each has a completely different layout,space and structure.The comparative findings of this research provide a point of reference for establishing guidelines to preserve the integrity of ancient towns worldwide.In this paper,we compare the geographical conditions with the layout and texture of the streets by Google Earth Pro.And we analyze the details of spaces along the river zones,architectural styles and building decorations in order to research the relationship between the natural environment and the human settlement conditions.We note the unfortunate common trend of commercial development steadily taking over the natural environment,particularly the rivers and unique elements of the old towns.Finally,we summarize the similarities and differences of the spatial forms among these towns and put forward proposals for the further development of ancient towns.This research is important for all regions which stand to lose their national treasures.Consequently,measures should be to taken to curtail hyper development before we lose our historicscenery.展开更多
There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that ma...There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that made by belt press.With the on-going improvement in technology,know-how & accumulated experiences, perhaps it’ s time for us to review the qualities & performances of synthetic diamond made by the cubic press more objectively.Studies were carried out on the performances of the two kinds of diamond by choosing from top brands & top qualities,with coarser mesh sizes 20/30 & 30/40.Comparisons were made on parameters, such as TI,TTI,PPC,bulk density,compact,roughness and arealight.And the diamonds chosen were used to produce the relevant diamond core drill bits and saw blades,their respective cutting performances such as cutting efficiency,segments consumption were measured and reported in this paper.The report demonstrates that producing the high quality diamond does not depend on the type of presses(Belt or Cubic) but rather on the know-how,technology and what it is made.展开更多
Fault diagnosis of liquid rocket propulsion systems (LRPSs) is a very important issue in space launch activities particularly when manned space missions are accompanied, since the safety and reliability can be signi...Fault diagnosis of liquid rocket propulsion systems (LRPSs) is a very important issue in space launch activities particularly when manned space missions are accompanied, since the safety and reliability can be significantly enhanced by exploiting an efficient fault diagnosis system. Currently, inverse problem-based diagnosis has attracted a great deal of research attention in fault diagnosis domain. This methodology provides a new strategy to model-based fault diagnosis for monitoring the health of propulsion systems. To solve the inverse problems arising from the fault diagnosis of LRPSs, GAs have been adopted in recent years as the first and effective choice of available numerical optimization tools. However, the GA has many control parameters to be chosen in advance and there still lack sound theoretical tools to analyze the effects of these parameters on diagnostic performance analytically. In this paper a comparative study of the influence of GA parameters on diagnostic results is conducted by performing a series of numerical experiments. The objective of this study is to investigate the contribution of individual algorithm parameter to final diagnostic result and provide reasonable estimates for choosing GA parameters in the inverse problem-based fault diagnosis of LRPSs. Some constructive remarks are made in conclusion and will be helpful for the implementation of GA to the fault diagnosis practice of LRPSs in the future.展开更多
Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on com...Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE's theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE's theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.82173620 to Yang Zhao and 82041024 to Feng Chen)partially supported by the Bill&Melinda Gates Foundation(Grant No.INV-006371 to Feng Chen)Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochastic models is not well understood.The present study aimed to address this gap by conducting a comparative study using the susceptible,exposed,infectious,and recovered(SEIR)model and its extended CMs from the coronavirus disease 2019 modeling literature.We demonstrated the equivalence of the numerical solution of CMs using the Euler scheme and their stochastic counterparts through theoretical analysis and simulations.Based on this equivalence,we proposed an efficient model calibration method that could replicate the exact solution of CMs in the corresponding stochastic models through parameter adjustment.The advancement in calibration techniques enhanced the accuracy of stochastic modeling in capturing the dynamics of epidemics.However,it should be noted that discrete-time stochastic models cannot perfectly reproduce the exact solution of continuous-time CMs.Additionally,we proposed a new stochastic compartment and agent mixed model as an alternative to agent-based models for large-scale population simulations with a limited number of agents.This model offered a balance between computational efficiency and accuracy.The results of this research contributed to the comparison and unification of deterministic CMs and stochastic models in epidemic modeling.Furthermore,the results had implications for the development of hybrid models that integrated the strengths of both frameworks.Overall,the present study has provided valuable epidemic modeling techniques and their practical applications for understanding and controlling the spread of infectious diseases.
文摘In the digital age, the data exchanged within a company is a wealth of knowledge. The survival, growth and influence of a company in the short, medium and long term depend on it. Indeed, it is the lifeblood of any modern company. A companys operational and historical data contains strategic and operational knowledge of ever-increasing added value. The emergence of a new paradigm: big data. Today, the value of the data scattered throughout this mother of knowledge is calculated in billions of dollars, depending on its size, scope and area of intervention. With the rise of computer networks and distributed systems, the threats to these sensitive resources have steadily increased, jeopardizing the existence of the company itself by drying up production and losing the interest of customers and suppliers. These threats range from sabotage to bankruptcy. For several decades now, most companies have been using encryption algorithms to protect and secure their information systems against the threats and dangers posed by the inherent vulnerabilities of their infrastructure and the current economic climate. This vulnerability requires companies to make the right choice of algorithms to implement in their management systems. For this reason, the present work aims to carry out a comparative study of the reliability and effectiveness of symmetrical and asymmetrical cryptosystems, in order to identify one or more suitable for securing academic data in the DRC. The analysis of the robustness of commonly used symmetric and asymmetric cryptosystems will be the subject of simulations in this article.
文摘Data compression plays a key role in optimizing the use of memory storage space and also reducing latency in data transmission. In this paper, we are interested in lossless compression techniques because their performance is exploited with lossy compression techniques for images and videos generally using a mixed approach. To achieve our intended objective, which is to study the performance of lossless compression methods, we first carried out a literature review, a summary of which enabled us to select the most relevant, namely the following: arithmetic coding, LZW, Tunstall’s algorithm, RLE, BWT, Huffman coding and Shannon-Fano. Secondly, we designed a purposive text dataset with a repeating pattern in order to test the behavior and effectiveness of the selected compression techniques. Thirdly, we designed the compression algorithms and developed the programs (scripts) in Matlab in order to test their performance. Finally, following the tests conducted on relevant data that we constructed according to a deliberate model, the results show that these methods presented in order of performance are very satisfactory:- LZW- Arithmetic coding- Tunstall algorithm- BWT + RLELikewise, it appears that on the one hand, the performance of certain techniques relative to others is strongly linked to the sequencing and/or recurrence of symbols that make up the message, and on the other hand, to the cumulative time of encoding and decoding.
基金Sponsored by National Natural Science Foundation of China(51508471)Philosophy and Social Science Program of Sichuan Province(MD16E017)+3 种基金Soft Science Programs of Chengdu City(2015-RK00-00270-ZF)Fundamental Research Funds for the Central Universities for Scientific and Technological Innovation Project(2682017CX016)Teaching Research and Reform Project for Undergraduate Education of Southwest Jiaotong University(201704048)2017 Student Research Training Program(170903)
文摘Due to the integrated development between Chengdu and Chongqing,there are a large number of residents flowing into the two cities from their surrounding areas,so community renewal is imminent.Because of the similarity in the historical and cultural background of the two places,a comparative analysis of the evolution of community space in Chengdu-Chongqing Region enables Chengdu and Chongqing learn from each other and speed up the pace of renewal.This paper analyzed the evolution of community space in main urban areas of Chengdu and Chongqing.Specifically,the evolution of community space in Chengdu and Chongqing went through three stages.The starting time of community renewal in the two places was very close,but the duration of each stage varied.The second stage of Chengdu continued for a longer time,so its renovation and renewal of the community space was more detailed and thorough,and the emphasis and extension direction of the evolution of the community space were different.The evolution of community space in both Chengdu and Chongqing went through"mechanical renewal of demolition and construction—small-scale gradual renewal",but the path of renewal and development of the community space in Chengdu was faster.This paper,from the perspective of the evolution of community space,put forward the framework and content of community renewal in Chengdu and Chongqing based on community development and elaborated the community research content based on community development.
基金Supported by Nature Science Research Project of Education Depart-ment of Guizhou Province ([2009]0009)Graduate Education In-novation Project of Guiyang College of Traditional Chinese Medicine(ZYYCX10023)~~
文摘[Objective] In order to identify and comparatively study leaves of ethnic medicine Gaultheria yunnanensis from different regions of Guizhou.[Method] Characteristics,microscopic,physical and chemical identification were studied on Gaultheria yunnanensis.[Result] There was no obvious difference in characteristics and microscopic sections among Gaultheria yunnanensis leaves from different regions.Blue fluorescence spots were observed clearly by TLC(Thin Layer Chromatography) test.[Conclusion]The study provided a basis for improvement of the quality standard of the Gaultheria yunnanensis.
文摘Both metonymy and metaphor are very important in our cognitive activities, but there are some distinctions and common grounds between them. This paper mainly deals with in what way they distinct in some aspects, while how they are related to each other in other aspects.
基金Supported by the Research Project of the Research Center of Hubei Logistics Development,China (2011A03)the Humanities and Social Sciences Project of Hubei Provincial Department of Education Project,China (2011jyty027)~~
文摘By introducing the analytic hierarchy process (AHP), a model is constructed to compare the logistics development level of cold chain for agricultural products between China and other developed countries such as United States, Japan and Euro- pean. The paper makes a comparative study on the development levels of agricultural cold chain logistics in China and developed countries from the aspects of the level of cold chain logistics facilities and equipments, the degree of cold chain logistics market-oriented and the capacity of cold chain logistics, then determines the problems of cold chain logistics in China. With the experiences learning from developed countries, some countermeasures are proposed to resolve those problems of cold chain logistics for agricultural products development combining with the national conditions in China.
文摘Simile, as a kind of commonly used rhetoric, plays a vital role in people's daily life. The appropriate using of simile can make language much more refine, veracious, and lifelike, can vividly present the person, the thing, the scene and so on to achieve better effects. Simile makes the finishing point in Chinese and English. However, because of the differences on culture, history, geography, customs, expressing ways and so on, there are some structural differences between Chinese and English simile. This paper will carry out the comparative study on the structure of Chinese and English simile.
文摘The aim of the paper is to give a general comparison about the structural composition of the AUX in English and Chinese mainly from the perspective of tense-aspect.Based on the basic construction of English AUX system,which includes such elements as Tense,Modal,Perfect aspect,Progressive aspect and Passive,the paper focuses on comparing the syntactic characteristics of tense element in the two languages.The final part of the paper briefly summarized predicted learning problems that Chinese learners of English as well as English learners of Chinese would have in learning English and Chinese respectively.
文摘Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of abstracts from a macro perspective and often employed either outdated texts,such as those over a decade old,or papers written by authors with lower English academic writing proficiency as research material.In this study,we analyzed forty abstracts from leading journals in applied linguistics,evenly split between Chinese and international journals.It revealed that the use of nominalization in abstracts by Chinese and international scholars showed similarities due to the universal academic requirement for conciseness.However,due to cultural and educational differences,each group differed in their respective language choices and nominalization usage.By analyzing the application of nominalization in different cultural contexts,the results of our study offered practical suggestions for crafting abstracts that effectively convey information,thereby,contributing to the broader academic community.
基金This paper is a result of the Major Project for the Research and Development of Marxist Theory and Major Project of the National Social Science Foundation of China(NSSFC)“Study on the In-Depth Implementation of the Coordinated Regional Development Strategy”(Grant No.2001MZD011)General Project of the National Natural Science Foundation of China(NSFC)“Spatial Structure and Effective Governance of Cities under the Big Data Horizon”(Grant No.72073094)and Key Project of the NSFC“Study on the Transformative Development and Governance of Small Towns in China”(Grant No.71834005).
文摘In its new development stage,China seeks to derive new dynamism from reform and opening up at a higher level to boost consumption and services.This process coincides with a further differentiation of comparative advantages across regions.Economic activity and population will continue to concentrate in clusters in coastal and central cities amid a continuous outflow of population from remote areas.Development expansion from coastal to interior regions and from central cities to the periphery will promote a new regional development paradigm of“dual centers and periphery”.Therefore,China’s regional development strategy should follow the new theory of seeking relative equilibrium amid development,identify regions of population inflow and outflow,and explore a new development path of regional specialization and coordination.By deepening market reforms and increasing central government coordination,the country is poised to improve the spatial allocation of resources and unleash institutional dividends in the process of developing a unified national market.
基金Supported by the MOE(Ministry of Education in China)Project of Humanities and Social Sciences(19YJA790105).
文摘This paper analyzes and compares the key factors influencing food security in two populous countries(China and India),and cate-gorizes them into three types:agricultural production,economic development and income level,and income distribution.Using the prevalence of undernourishment as an indicator of food security,the paper empirically tests the degree of impact of various factors on food security in both countries using Tobit regression and Newey regression methods.The study finds that improving the level of economic development can significantly enhance food security in both countriesꎻreducing the Gini coefficient has a significant impact on India,but not on Chinaꎻincreasing the agricultural production per capita has a much greater effect on China than on India.Therefore,both countries should take measures that are both similar and different according to their national conditions to improve their food security level.
基金support from the State Key Program of the National Natural Science Foundation of China (No. 51534008)
文摘A comparative study is conducted to compare the theory and application effect of two accident causation models, the human factors analysis and classification system(HFACS) and the accident causation "2-4" model(24 Model), as well as to provide a reference for safety researchers and accident investigators to select an appropriate accident analysis method. The two models are compared in terms of their theoretical foundations, cause classifications, accident analysis processes, application ranges, and accident prevention strategies. A coal and gas outburst accident is then analyzed using both models, and the application results are compared. This study shows that both the 24 Model and HFACS have strong theoretical foundations, and they can each be applied in various domains. In addition, the cause classification in HFACS is more practical, and its accident analysis process is more convenient. On the other hand, the 24 Model includes external factors, which makes the cause analysis more systematic and comprehensive. Moreover, the 24 Model puts forward more corresponding measures to prevent accidents.
基金Supported by Humanities and social science program from Education Department,Sichuan Province(12SD0171)
文摘City park, as an everlasting cultural carrier, is an important place for the expression of regional culture. The concept and characteristics of regional culture are summarized, and regional culture inheritance carrier mainly includes land, garden style, garden building, etc. There are generally six methods: reservation, restoration, inheritance and development, extraction, reappearance, and creation. Taking Fule mountain Park in Mianyang City for example, combination of regional culture and landscape is analyzed.
基金supported by the National Natural Science Foundation of China(41977258)the National Key Research and Development Program of China(2017YFC1501005 and 2018YFC1504704)。
文摘Determining the main controlling factors of earthquake-triggered geohazards is a prerequisite for studying earthquake geohazards and post-disaster emergency response.By studying these factors,the geomorphic and geological factors controlling the nature,condition,and distribution of earthquake-induced geohazards can be analyzed.Such insights facilitate earthquake disaster prediction and emergency response planning.The authors combined field investigations and spatial data analysis to examine geohazards induced by seismic events,examining ten earthquakes including the Wenchuan,Yushu,Lushan events,to elucidate the main control factors of seismic geohazard.The authors observed that seismic geohazard occurrence is usually affected by many factors,among which active nature of the seismogenic fault,seismic peak ground acceleration(PGA),topographic slope and geomorphic height differences,and distance from the fault zone and river system are the most important.Compared with strike-slip earthquakes,thrust earthquakes induce more high-altitude and high-speed remote landslides,which can cause great harm.Slopes of 0°–40°are prone to secondary seismic geohazards,which are mainly concentrated 0–6 km from the river system.Secondary geohazards are not only related to seismogenic fault but also influenced by the associated faults in the earthquake area.The maximum seismic PGA and secondary seismic geohazard number are positively correlated,and the horizontal and vertical ground motions play leading and promoting roles in secondary geohazard formation,respectively.Through the research,the spatial distribution of seismic geohazards is predicted,providing a basis for the formulation of emergency response plans following disasters.
基金supported by the National Science and Technology Pillar Program of China (Grant No.2008BAC37B01)the National Natural Science Foundation of China (Grant Nos. 40930950 and 40921160379)
文摘The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy parameterization-building energy model (UCP- BEM) urban physics scheme. The experiments were designed with a focus on the influence of different urban intensities, which are represented by a different fractional coverage of natural land, buildings, and energy consumption inside buildings in an urban environment. The results of this study indicate that urban areas notably influence fog evolution when natural land is reduced to a small fraction (e.g., less than 10%). Developed land changes fog evolution through urban effects. Higher urban intensity (HUI) generally results in warmer temperatures and lower wind speeds throughout the day, while inhibiting morning specific humidity loss and afternoon specific humidity gain because of the HUI effect on surface heat flux, surface roughness, and surface moisture flux. HUI leads to later and weaker liquid water content formation, with a higher liquid water content base, primarily due to its effect on near surface temperatures. This finding implies that HUI may inhibit the conditions for fog formation. In addition, urban areas with equal natural and developed land coverage seem to greatly enhance the upward surface moisture flux, which is attributed to the combination of a relatively large potential evaporation on developed land and an ample moisture supply from natural land. As a result, the specific humidity increases in the afternoon.
文摘The purpose of this study is to address the problem of ancient towns dying out in developing countries,particularly China.Intensifying conflicts between human settlements and the natural environment are described,and guidelines are proposed for the development of waterside ancient towns in China’s southern Shaanxi Province in the interest of conserving cultural and natural heritage.The towns of Qingmuchuan,Fenghuang and Houliu were selected as representative examples due to their strong reputation among tourists.They have the characteristics of traditional southern Shaanxi towns,but each has a completely different layout,space and structure.The comparative findings of this research provide a point of reference for establishing guidelines to preserve the integrity of ancient towns worldwide.In this paper,we compare the geographical conditions with the layout and texture of the streets by Google Earth Pro.And we analyze the details of spaces along the river zones,architectural styles and building decorations in order to research the relationship between the natural environment and the human settlement conditions.We note the unfortunate common trend of commercial development steadily taking over the natural environment,particularly the rivers and unique elements of the old towns.Finally,we summarize the similarities and differences of the spatial forms among these towns and put forward proposals for the further development of ancient towns.This research is important for all regions which stand to lose their national treasures.Consequently,measures should be to taken to curtail hyper development before we lose our historicscenery.
文摘There are mainly two kinds of equipment to produce synthetic diamond,namely belt press & cubic press.It has been customary in the industry to regard synthetic diamond produced by cubic press is inferior to that made by belt press.With the on-going improvement in technology,know-how & accumulated experiences, perhaps it’ s time for us to review the qualities & performances of synthetic diamond made by the cubic press more objectively.Studies were carried out on the performances of the two kinds of diamond by choosing from top brands & top qualities,with coarser mesh sizes 20/30 & 30/40.Comparisons were made on parameters, such as TI,TTI,PPC,bulk density,compact,roughness and arealight.And the diamonds chosen were used to produce the relevant diamond core drill bits and saw blades,their respective cutting performances such as cutting efficiency,segments consumption were measured and reported in this paper.The report demonstrates that producing the high quality diamond does not depend on the type of presses(Belt or Cubic) but rather on the know-how,technology and what it is made.
基金This work was supported by the National Natural Science Foundation of China(No.50106005)
文摘Fault diagnosis of liquid rocket propulsion systems (LRPSs) is a very important issue in space launch activities particularly when manned space missions are accompanied, since the safety and reliability can be significantly enhanced by exploiting an efficient fault diagnosis system. Currently, inverse problem-based diagnosis has attracted a great deal of research attention in fault diagnosis domain. This methodology provides a new strategy to model-based fault diagnosis for monitoring the health of propulsion systems. To solve the inverse problems arising from the fault diagnosis of LRPSs, GAs have been adopted in recent years as the first and effective choice of available numerical optimization tools. However, the GA has many control parameters to be chosen in advance and there still lack sound theoretical tools to analyze the effects of these parameters on diagnostic performance analytically. In this paper a comparative study of the influence of GA parameters on diagnostic results is conducted by performing a series of numerical experiments. The objective of this study is to investigate the contribution of individual algorithm parameter to final diagnostic result and provide reasonable estimates for choosing GA parameters in the inverse problem-based fault diagnosis of LRPSs. Some constructive remarks are made in conclusion and will be helpful for the implementation of GA to the fault diagnosis practice of LRPSs in the future.
基金Project(RG086/10AET) supported by the Institute of Research Management and Monitoring,University of Malaya,Malaysia
文摘Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE's theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE's theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design.