Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible expl...Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible explanation of this can be found in the unique nature of the forest management area which is populated with various kinds of rare and endangered species.This issue has been brought to light as a result of the nomination of northern Okinawa Island in 2018 as a candidate for World Natural Heritage site.The nomination has raised public awareness to the possibility of conflicting management objectives between timber extraction and the conservation of habitat for forest-dependent wildlife species.Managing exclusively for one objective over the other may fail to meet the demand for both forest products and wildlife habitat,ultimately jeopardizing the stability of human and wildlife communities.It is therefore important to achieve a better balance between the objective of timber production and conservation of wildlife habitat.Despite the significance of this subject area,current ongoing discussions on how to effectively manage for forest resources,often lack scientific basis to make sound judgement or evaluate tradeoffs between conflicting objectives.Quantifying the effect of these forest management activities on wildlife habitat provides useful and important information needed to make forest management and policy decisions.In this study we develop a spatial timber harvest scheduling model that incorporates habitat suitability index(HSI)models for the Okinawa Rail(Gallirallus okinawae),an endangered avian species found on Okinawa,Japan.To illustrate how the proposed coupling model assembles spatial information,which ultimately aids the study of forest management effects on wildlife habitat,we apply these models to a forest area in Okinawa and conduct a simple simulation analysis.展开更多
This study aims at quantifying the most important ecosystem services: forage production, timber production and carbon sequestration provided by Pterocarpus lucens to local communities of Ferlo Biosphere Reserve. The r...This study aims at quantifying the most important ecosystem services: forage production, timber production and carbon sequestration provided by Pterocarpus lucens to local communities of Ferlo Biosphere Reserve. The results suggested that the ecological structure of Pterocarpus lucens revealed a bell-shaped form with left dissymmetric distribution indicating a predominance of individuals with small circumference and height. A regression using the software Minitab 16, with circumference and the height as explanatory variables, has allowed a development of predictive models for the estimation of the produced forage and the quantification of the timber supplied by one of the most used plant species in Sahelian pastures. Forage production of Pterocarpus lucens was estimated at 178 kg DM/ha. This large value of forage showed the predominance of this species in animal feed in the Sahel. The quantity of wood produced was 545 kg DM/ha while the quantity of above ground sequestered carbon was 325.35 kg of C/ha. Those estimations are interesting in the implementation context of the Ferlo Biosphere Reserve which aims at matching the productive capacity of ecosystems with the needs of local communities.展开更多
Given the challenges of manufacturing resource sharing and competition in the modern manufacturing industry,the coordinated scheduling problem of parallel machine production and transportation is investigated.The prob...Given the challenges of manufacturing resource sharing and competition in the modern manufacturing industry,the coordinated scheduling problem of parallel machine production and transportation is investigated.The problem takes into account the coordination of production and transportation before production as well as the disparities in machine spatial position and performance.A non-cooperative game model is established,considering the competition and self-interest behavior of jobs from different customers for machine resources.The job from different customers is mapped to the players in the game model,the corresponding optional processing machine and location are mapped to the strategy set,and the makespan of the job is mapped to the payoff.Then the solution of the scheduling model is transformed into the Nash equilibrium of the non-cooperative game model.A Nash equilibrium solution algorithm based on the genetic algorithm(NEGA)is designed,and the effective solution of approximate Nash equilibrium for the game model is realized.The fitness function,single-point crossover operator,and mutation operator are derived from the non-cooperative game model’s characteristics and the definition of Nash equilibrium.Rules are also designed to avoid the generation of invalid offspring chromosomes.The effectiveness of the proposed algorithm is demonstrated through numerical experiments of various sizes.Compared with other algorithms such as heuristic algorithms(FCFS,SPT,and LPT),the simulated annealing algorithm(SA),and the particle swarm optimization algorithm(PSO),experimental results show that the proposed NE-GA algorithm has obvious performance advantages.展开更多
A two-agent production and transportation coordinated scheduling problem in a single-machine environment is suggested to compete for one machine from different downstream production links or various consumers.The jobs...A two-agent production and transportation coordinated scheduling problem in a single-machine environment is suggested to compete for one machine from different downstream production links or various consumers.The jobs of two agents compete for the processing position on a machine,and after the pro-cessed,they compete for the transport position on a transport vehicle to be trans-ported to two agents.The two agents have different objective functions.The objective function of the first agent is the sum of the makespan and the total trans-portation time,whereas the objective function of the second agent is the sum of the total completion time and the total transportation time.Given the competition between two agents for machine resources and transportation resources,a non-cooperative game model with agents as game players is established.The job pro-cessing position and transportation position corresponding to the two agents are mapped as strategies,and the corresponding objective function is the utility func-tion.To solve the game model,an approximate Nash equilibrium solution algo-rithm based on an improved genetic algorithm(NE-IGA)is proposed.The genetic operation based on processing sequence and transportation sequence,as well as the fitness function based on Nash equilibrium definition,are designed based on the features of the two-agent production and transportation coordination scheduling problem.The effectiveness of the proposed algorithm is demonstrated through numerical experiments of various sizes.When compared to heuristic rules such as the Longest Processing Time first(LPT)and the Shortest Processing Time first(SPT),the objective function values of the two agents are reduced by 4.3%and 2.6% on average.展开更多
Results of the global shale gas resources show that minable resources of global shale gas are 187 trillion cubic meters (tern), of which China accounts for 36 tcm (about 20% of the total amount), which is mainly d...Results of the global shale gas resources show that minable resources of global shale gas are 187 trillion cubic meters (tern), of which China accounts for 36 tcm (about 20% of the total amount), which is mainly distributed in the Sichuan Basin, Yangtze Terrace, and Ordos Basin. From 2009 to 2012, China completed an accumulative number of 129 drilling wells related to shale gas, including 46 investigated vertical wells, 55 exploration wells and 28 evaluation wells, with 2012 production ranging from 25 million cubic meters (mcm) to 30 mcm.展开更多
In this paper,a new algorithm relaxation-strategy-based modification branchand-bound algorithm is developed for a type of solving the minimum cost transportationproduction problem with concave production costs.The maj...In this paper,a new algorithm relaxation-strategy-based modification branchand-bound algorithm is developed for a type of solving the minimum cost transportationproduction problem with concave production costs.The major improvement of the proposed new method is that modification algorithm reinforces the bounding operation using a Lagrangian relaxation,which is a concave minimization but obtains a tighter bound than the usual linear programming relaxation.Some computational results are included.Computation results indicate that the algorithm can solve fairly large scale problems.展开更多
Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect...Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect, hadron-induced nuclear reactions, hypernucleus, etc.The neck fragmentation in Fermi-energy heavy-ion collisions is investigated for extracting the symmetry energy at subsaturation densities. The isospin effects, in-medium properties, and the behavior of high-density symmetry energy in medium-and high-energy heavy-ion collisions are thoroughly discussed. The hypernuclide dynamics formed in heavy-ion collisions and in hadron-induced reactions is analyzed and addressed in the future experiments at the high-intensity heavy-ion accelerator facility(HIAF).展开更多
The aim of this paper is to compare block-structured linear programming (LP) models against other practical optimization methods for solving downstream product refinery problems using a solution method different fro...The aim of this paper is to compare block-structured linear programming (LP) models against other practical optimization methods for solving downstream product refinery problems using a solution method different from the existing ones (like mixed integer linear programming (MILP) method). The work X-rays the Nigerian petroleum refining industries and their channel of distribution in the local setting and identifies the critical features of scheduling and allocation of refined crude products; either for distribution within the country or for exportation to the international market. Applying our model to the distribution model, the computational results reveal a better route with lowest transportation cost for the scheduling problem and the best optimal blend with higher revenue for the production problem.展开更多
The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for...The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for hydrogen production.Despite remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable obstacle.This impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles detachment.To address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis system.Compared to constant voltage electrolysis(hydrogen production rate:51.6 m L h^(-1),energy consumption:5.37 kWh Nm-^(3)H_(2)),this strategy(hydrogen production rate:66 m L h^(-1),energy consumption:3.83 kWh Nm-^(3)H_(2))increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic(PV)system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 V.The combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis(PDE)dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode surface.As such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport processes.This promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors.展开更多
The tradeoffs and optimizations of ecosystem services are the key research fields of ecology and geography.It is necessary to maximize the overall benefit of timber production and carbon storage for forest ecological ...The tradeoffs and optimizations of ecosystem services are the key research fields of ecology and geography.It is necessary to maximize the overall benefit of timber production and carbon storage for forest ecological development in China.We selected the Huitong National Research Station of Forest Ecosystem as our study area,and used In VEST model to evaluate timber production and carbon storage quantitatively.The results showed that:(1)While timber production increased with harvesting intensity over the planning horizon,carbon storage decreased.There were tradeoffs between timber production and carbon storage according to the significant negative relationship.(2)While the overall benefit of timber production and carbon storage increased with harvesting intensity,the value of tradeoffs decreased.T1 and T2 scenarios,with harvesting intensity of 10%–20% every 10 years,are the optimum management regimes for the two ecosystem services to gain more benefit and less tradeoffs.(3)The current harvesting intensity in Huitong County was slightly higher than the optimum harvesting intensity.On practical dimension,these findings suggested that obvious objectives are needed to formulate the corresponding countermeasures of tradeoffs,in order to realize the improvement of ecosystem services and the optimization of ecosystem structures.展开更多
Wood products provide a relatively long-term carbon storage mechanism.Due to lack of consistent datasets on these products,however,it is difficult to determine their carbon contents.The main purpose of this study was ...Wood products provide a relatively long-term carbon storage mechanism.Due to lack of consistent datasets on these products,however,it is difficult to determine their carbon contents.The main purpose of this study was to quantify forest disturbance and timber product output(TPO)using time series Landsat observations for North Carolina.The results revealed that North Carolina had an average forest disturbance rate of 178,000 ha per year from 1985 to 2010.The derived disturbance products were found to be highly correlated with TPO survey data,explaining up to 87%of the total variance of county level industrial roundwood production.State level TPO estimates derived using the Landsat-based disturbance products tracked those derived from ground-based survey data closely.The TPO modeling approach developed in this study complements the ground-based TPO surveys conducted by the US Forest Service.It allows derivation of TPO estimates for the years that did not have TPO survey data,and may be applicable in other regions or countries where at least some ground-based survey data on timber production are available for model development and dense time series Landsat observations exist for developing annual forest disturbance products.展开更多
Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium ch...Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames (ORFs) were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them (penT) was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily (MFS) and contains 12 transmembrane spanning domains (TMS). During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid (PAA) and phenoxyacetic acid (POA). Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane. Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames (ORFs) were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them (penT) was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily (MFS) and contains 12 transmembrane spanning domains (TMS). During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid (PAA) and phenoxyacetic acid (POA). Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane.展开更多
This study uses simulations to investigate the effects of implementing two different Japanese forestry subsidy systems on timber production and carbon stock, and examines the consequences for harvesting strategies. A...This study uses simulations to investigate the effects of implementing two different Japanese forestry subsidy systems on timber production and carbon stock, and examines the consequences for harvesting strategies. An existing Local Yield Table Construction System (LYCS), a wood conversion algorithm, and a harvesting cost model were used in the simulations to test the applicability of different subsidies to the thinning of stands. Using forest inventory data collected by local government staff, simulation output was used to calculate forestry profits, carbon stocks, subsidies, the amount of labor required, and the cost effectiveness of investing in subsidies. By comparing the output of simulations based on two scenarios, we found that both the clear-cutting area and the amount of harvested timber were larger under Scenario 2, in which the rules governing subsidy allocations are more relaxed, than under Scenario 1, in which the rules are more restrictive. Because the harvested timber under Scenario 1 was mainly produced by clear-cutting, the forestry profits and the subsidy predicted in the early period of the simulation, were larger under Scenario 1 than under Scenario 2. In contrast, the carbon stock was larger under Scenario 2 than under Scenario 1. The simulation model is likely to be useful for improving Plan-Do-Check-Act cyclesimplemented in Japanese forest management systems.展开更多
The green production of ammonia,in an electrochemical flow cell under ambient conditions,is a promising way to replace the energy-intensive Haber-Bosch process.In the operation of this flow cell with an alkaline elect...The green production of ammonia,in an electrochemical flow cell under ambient conditions,is a promising way to replace the energy-intensive Haber-Bosch process.In the operation of this flow cell with an alkaline electrolyte,water is produced at the anode but also required as an essential reactant at the cathode for nitrogen reduction.Hence,water from the anode is expected to diffuse through the membrane to the cathode to compensate for the water needed for nitrogen reduction.Excessive water permeation,however,tends to increase the possibility of water flooding,which would not only create a large barrier for nitrogen delivery and availability,but also lead to severe hydrogen evolution as side reaction,and thus significantly lower the ammonia production rate and Faradaic efficiency.In this work,the water flooding phenomenon in flow cells for ammonia production via electrocatalytic nitrogen reduction is verified via the visualization approach and the electrochemical cell performance.In addition,the effects of the nitrogen flow rate,applied current density,and membrane thickness on the water crossover flux and ammonia production rate are comprehensively studied.The underlying mechanism of water transport through the membrane,including diffusion and electro-osmotic drag,is precisely examined and specified to provide more insight on water flooding behavior in the flow cell.展开更多
Preservative-treated pinewood is mildewproof, anticorrosive and mothproof, with the long durability and environmental protection as its fine performance. It has become an important material for landscape construction ...Preservative-treated pinewood is mildewproof, anticorrosive and mothproof, with the long durability and environmental protection as its fine performance. It has become an important material for landscape construction for the wide pine material sources, low price, less deformation, moderate density, good fl exibility and strength, fine texture and good integration with the natural environment. On the basis of introducing pinewood species, preservatives and production process of preservative-treated pinewood, this paper focuses on the application of preservative-treated pinewood used in log cabin, pavilion, service buildings and other garden timber architecture, as well as roads, platforms, bridges, rails, gallery frames, pergolas and other opuscules.展开更多
A seamless multimodal transit system has been a goal for transportation planners and users. Owing to the developments of advanced public transportation and telecom technologies such as automatic vehicle location (AVL)...A seamless multimodal transit system has been a goal for transportation planners and users. Owing to the developments of advanced public transportation and telecom technologies such as automatic vehicle location (AVL) and real-time passenger information system, key just-in-time (JIT) concepts can now be realized in process design and coordinated scheduling to shape a seamless multimodal transit system. JIT refers to a production system that times both movements of goods during production and delivery from suppliers together. It meets the same logic for seamless multimodal services. Therefore, this study innovatively analyzes possible public transportation technologies for JIT uses;moreover, to layout the possible application frame-work of a transportation technology based JIT multimodal transit system for main station area in Taipei city. With this innovative framework, multimodal transit services can deliver to the right place at right time.展开更多
The separation and transport of photogenerated carriers is regarded as a curial factor in photocatalytic H_(2)pro-duction.As known in solar cells and photoelectron-chemistry,to strengthen the electron conduction for e...The separation and transport of photogenerated carriers is regarded as a curial factor in photocatalytic H_(2)pro-duction.As known in solar cells and photoelectron-chemistry,to strengthen the electron conduction for effective utilization of carriers,the electron transport material(ETM)is widely applied.Herein,inspired by the function of ETM,we adopted barium stannate(BaSnO_(3),labeled as BSO)as an excellent ETM which had the merits of high electron mobility,suitable conduction band position and simple preparation,to adjust the carrier kinetics of dye Eosin Y(EY)-sensitized photocatalytic system.Detailly,the photocatalytic system with the spatial sepa-ration sites of photogenerated carriers excitation and water reduction reaction was elaborately constructed,that was,dye EY-sensitized BSO(EY/BSO)for photocatalytic H_(2)production.The photocatalytic H_(2)-production rate of EY/BSO(257𝜇mol·h^(−1)·g EY^(−1))in the absence of noble metals was 28.6 times higher than that of single EY(∼9𝜇mol·h^(−1)·g EY^(−1))under visible-light irradiation.With systematic and comprehensive characterizations,the formed electron transport channel by the bidentate bridging of EY on BSO could accelerate the transfer of photogenerated electrons from EY to BSO,promoting the effective separation of photogenerated carriers for the enhanced pho-tocatalytic performance.Moreover,the water reduction reaction for H_(2)production proceeded on the surface of BSO that acted as the H_(2)-evolution cocatalyst,avoiding the use of high-cost noble metals.Furthermore,based on the well-proved ETM-based concept in the EY/BSO system,La-doped BaSnO_(3)(LBSO)with better electron trans-port ability was adopted to construct EY/LBSO system(344𝜇mol·h^(−1)·g EY^(−1))which showed better photocatalytic activity than EY/BSO.展开更多
This paper introduces the general condition of forestry resources of China and the demand and supply of timber and forest products. The market for timber and forest producls has borne dual pressure because of the popu...This paper introduces the general condition of forestry resources of China and the demand and supply of timber and forest products. The market for timber and forest producls has borne dual pressure because of the population explosion and growth of the domestic economy. A major contemporary strategy for sustainable forestry includes the promotion of the Forest Products Industry (FPI), the substitution of other materials for timber,and the encouragement of imports of timber and forest products. The author analyzes the effect of these policies on the market for timber and forest products. In addition, the difficulties encountered by most mid-to large -scale state- owned forest enterprises during the transition from a centrally-planned economy to a market economy are examined. Finally, the author points out the countermeasures and means for reform of these old forest enterprises with a view toward future prosperity of the market for timber and forest products.展开更多
基金supported by a Grant-in-Aid for Scientific Researches (No. 16K12641&17H00806) from the Ministry of Education, Culture, Sports, Science, and technology of Japan
文摘Finding the right balance between timber production and the management of forest-dependent wildlife species,present a difficult challenge for forest resource managers and policy makers in Okinawa,Japan.A possible explanation of this can be found in the unique nature of the forest management area which is populated with various kinds of rare and endangered species.This issue has been brought to light as a result of the nomination of northern Okinawa Island in 2018 as a candidate for World Natural Heritage site.The nomination has raised public awareness to the possibility of conflicting management objectives between timber extraction and the conservation of habitat for forest-dependent wildlife species.Managing exclusively for one objective over the other may fail to meet the demand for both forest products and wildlife habitat,ultimately jeopardizing the stability of human and wildlife communities.It is therefore important to achieve a better balance between the objective of timber production and conservation of wildlife habitat.Despite the significance of this subject area,current ongoing discussions on how to effectively manage for forest resources,often lack scientific basis to make sound judgement or evaluate tradeoffs between conflicting objectives.Quantifying the effect of these forest management activities on wildlife habitat provides useful and important information needed to make forest management and policy decisions.In this study we develop a spatial timber harvest scheduling model that incorporates habitat suitability index(HSI)models for the Okinawa Rail(Gallirallus okinawae),an endangered avian species found on Okinawa,Japan.To illustrate how the proposed coupling model assembles spatial information,which ultimately aids the study of forest management effects on wildlife habitat,we apply these models to a forest area in Okinawa and conduct a simple simulation analysis.
文摘This study aims at quantifying the most important ecosystem services: forage production, timber production and carbon sequestration provided by Pterocarpus lucens to local communities of Ferlo Biosphere Reserve. The results suggested that the ecological structure of Pterocarpus lucens revealed a bell-shaped form with left dissymmetric distribution indicating a predominance of individuals with small circumference and height. A regression using the software Minitab 16, with circumference and the height as explanatory variables, has allowed a development of predictive models for the estimation of the produced forage and the quantification of the timber supplied by one of the most used plant species in Sahelian pastures. Forage production of Pterocarpus lucens was estimated at 178 kg DM/ha. This large value of forage showed the predominance of this species in animal feed in the Sahel. The quantity of wood produced was 545 kg DM/ha while the quantity of above ground sequestered carbon was 325.35 kg of C/ha. Those estimations are interesting in the implementation context of the Ferlo Biosphere Reserve which aims at matching the productive capacity of ecosystems with the needs of local communities.
基金supported in part by the Project of Liaoning BaiQianWan Talents ProgramunderGrand No.2021921089the Science Research Foundation of EducationalDepartment of Liaoning Province under Grand No.LJKQZ2021057 and WJGD2020001the Key Program of Social Science Planning Foundation of Liaoning Province under Grant L21AGL017.
文摘Given the challenges of manufacturing resource sharing and competition in the modern manufacturing industry,the coordinated scheduling problem of parallel machine production and transportation is investigated.The problem takes into account the coordination of production and transportation before production as well as the disparities in machine spatial position and performance.A non-cooperative game model is established,considering the competition and self-interest behavior of jobs from different customers for machine resources.The job from different customers is mapped to the players in the game model,the corresponding optional processing machine and location are mapped to the strategy set,and the makespan of the job is mapped to the payoff.Then the solution of the scheduling model is transformed into the Nash equilibrium of the non-cooperative game model.A Nash equilibrium solution algorithm based on the genetic algorithm(NEGA)is designed,and the effective solution of approximate Nash equilibrium for the game model is realized.The fitness function,single-point crossover operator,and mutation operator are derived from the non-cooperative game model’s characteristics and the definition of Nash equilibrium.Rules are also designed to avoid the generation of invalid offspring chromosomes.The effectiveness of the proposed algorithm is demonstrated through numerical experiments of various sizes.Compared with other algorithms such as heuristic algorithms(FCFS,SPT,and LPT),the simulated annealing algorithm(SA),and the particle swarm optimization algorithm(PSO),experimental results show that the proposed NE-GA algorithm has obvious performance advantages.
基金This work was supported in part by the Project of Liaoning BaiQianWan Talents Program under Grand No.2021921089the Science Research Foundation of Educational Department of Liaoning Province under Grand No.LJKQZ2021057 and WJGD2020001+2 种基金the Key Program of Social Science Planning Foundation of Liaoning Province under Grant L21AGL017the special project of SUT on serving local economic and social development decision-making under Grant FWDFGD2021019the“Double First-Class”Construction Project in Liaoning Province under Grant ZDZRGD2020037.
文摘A two-agent production and transportation coordinated scheduling problem in a single-machine environment is suggested to compete for one machine from different downstream production links or various consumers.The jobs of two agents compete for the processing position on a machine,and after the pro-cessed,they compete for the transport position on a transport vehicle to be trans-ported to two agents.The two agents have different objective functions.The objective function of the first agent is the sum of the makespan and the total trans-portation time,whereas the objective function of the second agent is the sum of the total completion time and the total transportation time.Given the competition between two agents for machine resources and transportation resources,a non-cooperative game model with agents as game players is established.The job pro-cessing position and transportation position corresponding to the two agents are mapped as strategies,and the corresponding objective function is the utility func-tion.To solve the game model,an approximate Nash equilibrium solution algo-rithm based on an improved genetic algorithm(NE-IGA)is proposed.The genetic operation based on processing sequence and transportation sequence,as well as the fitness function based on Nash equilibrium definition,are designed based on the features of the two-agent production and transportation coordination scheduling problem.The effectiveness of the proposed algorithm is demonstrated through numerical experiments of various sizes.When compared to heuristic rules such as the Longest Processing Time first(LPT)and the Shortest Processing Time first(SPT),the objective function values of the two agents are reduced by 4.3%and 2.6% on average.
文摘Results of the global shale gas resources show that minable resources of global shale gas are 187 trillion cubic meters (tern), of which China accounts for 36 tcm (about 20% of the total amount), which is mainly distributed in the Sichuan Basin, Yangtze Terrace, and Ordos Basin. From 2009 to 2012, China completed an accumulative number of 129 drilling wells related to shale gas, including 46 investigated vertical wells, 55 exploration wells and 28 evaluation wells, with 2012 production ranging from 25 million cubic meters (mcm) to 30 mcm.
基金Foundation item: Supported by the National Natural Science Foundation of China(10726016) Supported by the Hubei Province Natural Science Foundation Project(T200809 D200613002)
文摘In this paper,a new algorithm relaxation-strategy-based modification branchand-bound algorithm is developed for a type of solving the minimum cost transportationproduction problem with concave production costs.The major improvement of the proposed new method is that modification algorithm reinforces the bounding operation using a Lagrangian relaxation,which is a concave minimization but obtains a tighter bound than the usual linear programming relaxation.Some computational results are included.Computation results indicate that the algorithm can solve fairly large scale problems.
基金supported by the National Natural Science Foundation of China(Nos.11675226 and 11722546)the Major State Basic Research Development Program of China(Nos.2014CB845405 and 2015CB856903)
文摘Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect, hadron-induced nuclear reactions, hypernucleus, etc.The neck fragmentation in Fermi-energy heavy-ion collisions is investigated for extracting the symmetry energy at subsaturation densities. The isospin effects, in-medium properties, and the behavior of high-density symmetry energy in medium-and high-energy heavy-ion collisions are thoroughly discussed. The hypernuclide dynamics formed in heavy-ion collisions and in hadron-induced reactions is analyzed and addressed in the future experiments at the high-intensity heavy-ion accelerator facility(HIAF).
文摘The aim of this paper is to compare block-structured linear programming (LP) models against other practical optimization methods for solving downstream product refinery problems using a solution method different from the existing ones (like mixed integer linear programming (MILP) method). The work X-rays the Nigerian petroleum refining industries and their channel of distribution in the local setting and identifies the critical features of scheduling and allocation of refined crude products; either for distribution within the country or for exportation to the international market. Applying our model to the distribution model, the computational results reveal a better route with lowest transportation cost for the scheduling problem and the best optimal blend with higher revenue for the production problem.
基金National Natural Science Foundation of China(No.52476192,No.52106237)Natural Science Foundation of Heilongjiang Province(No.YQ2022E027)。
文摘The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for hydrogen production.Despite remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable obstacle.This impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles detachment.To address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis system.Compared to constant voltage electrolysis(hydrogen production rate:51.6 m L h^(-1),energy consumption:5.37 kWh Nm-^(3)H_(2)),this strategy(hydrogen production rate:66 m L h^(-1),energy consumption:3.83 kWh Nm-^(3)H_(2))increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic(PV)system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 V.The combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis(PDE)dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode surface.As such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport processes.This promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors.
基金The National Basic Research Program of China(973 Program),No.2015CB452702National Natural Science Foundation of China,No.41571098,No.41530749+2 种基金Key Programs of Chinese Academy of Sciences,ZDRW-ZS-2016-6-4-4Major Consulting Project of Strategic Development Institute,Chinese Academy of Sciences,No.Y02015003China Clean Development Mechanism Fund Grant Program(Climate Change Risk and Countermeasures in Xinjiang Region)
文摘The tradeoffs and optimizations of ecosystem services are the key research fields of ecology and geography.It is necessary to maximize the overall benefit of timber production and carbon storage for forest ecological development in China.We selected the Huitong National Research Station of Forest Ecosystem as our study area,and used In VEST model to evaluate timber production and carbon storage quantitatively.The results showed that:(1)While timber production increased with harvesting intensity over the planning horizon,carbon storage decreased.There were tradeoffs between timber production and carbon storage according to the significant negative relationship.(2)While the overall benefit of timber production and carbon storage increased with harvesting intensity,the value of tradeoffs decreased.T1 and T2 scenarios,with harvesting intensity of 10%–20% every 10 years,are the optimum management regimes for the two ecosystem services to gain more benefit and less tradeoffs.(3)The current harvesting intensity in Huitong County was slightly higher than the optimum harvesting intensity.On practical dimension,these findings suggested that obvious objectives are needed to formulate the corresponding countermeasures of tradeoffs,in order to realize the improvement of ecosystem services and the optimization of ecosystem structures.
基金This study contributes to the North American Carbon Program,with grant support from NASA’s Land Cover and Land Use Change,Terrestrial Ecology,Carbon Cycle Science,and Applied Sciences Programs.Additional support was provided by the US Geological Survey and USDA Forest Service.
文摘Wood products provide a relatively long-term carbon storage mechanism.Due to lack of consistent datasets on these products,however,it is difficult to determine their carbon contents.The main purpose of this study was to quantify forest disturbance and timber product output(TPO)using time series Landsat observations for North Carolina.The results revealed that North Carolina had an average forest disturbance rate of 178,000 ha per year from 1985 to 2010.The derived disturbance products were found to be highly correlated with TPO survey data,explaining up to 87%of the total variance of county level industrial roundwood production.State level TPO estimates derived using the Landsat-based disturbance products tracked those derived from ground-based survey data closely.The TPO modeling approach developed in this study complements the ground-based TPO surveys conducted by the US Forest Service.It allows derivation of TPO estimates for the years that did not have TPO survey data,and may be applicable in other regions or countries where at least some ground-based survey data on timber production are available for model development and dense time series Landsat observations exist for developing annual forest disturbance products.
基金supported by the grants from the Ministry of Science and Technology of China(Nos.2009CB118905 and 2010ZX09401-403)the Knowledge Innovation Program of the Chinese Academy of Sciences(Nos.KSCX2-EW-G-6 and KSCX2-EW-J-6)
文摘Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames (ORFs) were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them (penT) was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily (MFS) and contains 12 transmembrane spanning domains (TMS). During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid (PAA) and phenoxyacetic acid (POA). Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane. Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames (ORFs) were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them (penT) was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily (MFS) and contains 12 transmembrane spanning domains (TMS). During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid (PAA) and phenoxyacetic acid (POA). Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane.
基金supported in part by Research Fellowships from the Ministry of Land, Infrastructure, Transport and Tourism
文摘This study uses simulations to investigate the effects of implementing two different Japanese forestry subsidy systems on timber production and carbon stock, and examines the consequences for harvesting strategies. An existing Local Yield Table Construction System (LYCS), a wood conversion algorithm, and a harvesting cost model were used in the simulations to test the applicability of different subsidies to the thinning of stands. Using forest inventory data collected by local government staff, simulation output was used to calculate forestry profits, carbon stocks, subsidies, the amount of labor required, and the cost effectiveness of investing in subsidies. By comparing the output of simulations based on two scenarios, we found that both the clear-cutting area and the amount of harvested timber were larger under Scenario 2, in which the rules governing subsidy allocations are more relaxed, than under Scenario 1, in which the rules are more restrictive. Because the harvested timber under Scenario 1 was mainly produced by clear-cutting, the forestry profits and the subsidy predicted in the early period of the simulation, were larger under Scenario 1 than under Scenario 2. In contrast, the carbon stock was larger under Scenario 2 than under Scenario 1. The simulation model is likely to be useful for improving Plan-Do-Check-Act cyclesimplemented in Japanese forest management systems.
基金fully supported by a grant from the National Natural Science Foundation of China(Grant No.52022003).
文摘The green production of ammonia,in an electrochemical flow cell under ambient conditions,is a promising way to replace the energy-intensive Haber-Bosch process.In the operation of this flow cell with an alkaline electrolyte,water is produced at the anode but also required as an essential reactant at the cathode for nitrogen reduction.Hence,water from the anode is expected to diffuse through the membrane to the cathode to compensate for the water needed for nitrogen reduction.Excessive water permeation,however,tends to increase the possibility of water flooding,which would not only create a large barrier for nitrogen delivery and availability,but also lead to severe hydrogen evolution as side reaction,and thus significantly lower the ammonia production rate and Faradaic efficiency.In this work,the water flooding phenomenon in flow cells for ammonia production via electrocatalytic nitrogen reduction is verified via the visualization approach and the electrochemical cell performance.In addition,the effects of the nitrogen flow rate,applied current density,and membrane thickness on the water crossover flux and ammonia production rate are comprehensively studied.The underlying mechanism of water transport through the membrane,including diffusion and electro-osmotic drag,is precisely examined and specified to provide more insight on water flooding behavior in the flow cell.
基金Sponsored by Key Agricultural Sci-Tech Program of Shaanxi Province(2008K01-05)
文摘Preservative-treated pinewood is mildewproof, anticorrosive and mothproof, with the long durability and environmental protection as its fine performance. It has become an important material for landscape construction for the wide pine material sources, low price, less deformation, moderate density, good fl exibility and strength, fine texture and good integration with the natural environment. On the basis of introducing pinewood species, preservatives and production process of preservative-treated pinewood, this paper focuses on the application of preservative-treated pinewood used in log cabin, pavilion, service buildings and other garden timber architecture, as well as roads, platforms, bridges, rails, gallery frames, pergolas and other opuscules.
文摘A seamless multimodal transit system has been a goal for transportation planners and users. Owing to the developments of advanced public transportation and telecom technologies such as automatic vehicle location (AVL) and real-time passenger information system, key just-in-time (JIT) concepts can now be realized in process design and coordinated scheduling to shape a seamless multimodal transit system. JIT refers to a production system that times both movements of goods during production and delivery from suppliers together. It meets the same logic for seamless multimodal services. Therefore, this study innovatively analyzes possible public transportation technologies for JIT uses;moreover, to layout the possible application frame-work of a transportation technology based JIT multimodal transit system for main station area in Taipei city. With this innovative framework, multimodal transit services can deliver to the right place at right time.
基金the National Key Research and Devel-opment Program of China(Grant No:2022YFB3803600)the National Natural Science Foundation of China(Grant No.:22002126)+1 种基金the China Postdoctoral Science Foundation(Grant No.:2020M671938)the Fundamental Research Funds for the Central Universities.
文摘The separation and transport of photogenerated carriers is regarded as a curial factor in photocatalytic H_(2)pro-duction.As known in solar cells and photoelectron-chemistry,to strengthen the electron conduction for effective utilization of carriers,the electron transport material(ETM)is widely applied.Herein,inspired by the function of ETM,we adopted barium stannate(BaSnO_(3),labeled as BSO)as an excellent ETM which had the merits of high electron mobility,suitable conduction band position and simple preparation,to adjust the carrier kinetics of dye Eosin Y(EY)-sensitized photocatalytic system.Detailly,the photocatalytic system with the spatial sepa-ration sites of photogenerated carriers excitation and water reduction reaction was elaborately constructed,that was,dye EY-sensitized BSO(EY/BSO)for photocatalytic H_(2)production.The photocatalytic H_(2)-production rate of EY/BSO(257𝜇mol·h^(−1)·g EY^(−1))in the absence of noble metals was 28.6 times higher than that of single EY(∼9𝜇mol·h^(−1)·g EY^(−1))under visible-light irradiation.With systematic and comprehensive characterizations,the formed electron transport channel by the bidentate bridging of EY on BSO could accelerate the transfer of photogenerated electrons from EY to BSO,promoting the effective separation of photogenerated carriers for the enhanced pho-tocatalytic performance.Moreover,the water reduction reaction for H_(2)production proceeded on the surface of BSO that acted as the H_(2)-evolution cocatalyst,avoiding the use of high-cost noble metals.Furthermore,based on the well-proved ETM-based concept in the EY/BSO system,La-doped BaSnO_(3)(LBSO)with better electron trans-port ability was adopted to construct EY/LBSO system(344𝜇mol·h^(−1)·g EY^(−1))which showed better photocatalytic activity than EY/BSO.
文摘This paper introduces the general condition of forestry resources of China and the demand and supply of timber and forest products. The market for timber and forest producls has borne dual pressure because of the population explosion and growth of the domestic economy. A major contemporary strategy for sustainable forestry includes the promotion of the Forest Products Industry (FPI), the substitution of other materials for timber,and the encouragement of imports of timber and forest products. The author analyzes the effect of these policies on the market for timber and forest products. In addition, the difficulties encountered by most mid-to large -scale state- owned forest enterprises during the transition from a centrally-planned economy to a market economy are examined. Finally, the author points out the countermeasures and means for reform of these old forest enterprises with a view toward future prosperity of the market for timber and forest products.