In order to find out the applicability of the optimal pricing decision model based on conventional cost behavior model after activity based costing has given strong shock to the conventional cost behavior model and it...In order to find out the applicability of the optimal pricing decision model based on conventional cost behavior model after activity based costing has given strong shock to the conventional cost behavior model and its assumptions, detailed analyses have been made using the activity based cost behavior and cost volume profit analysis model, and it is concluded from these analyses that the theory behind the construction of optimal pricing decision model is still tenable under activity based costing, but the conventional optimal pricing decision model must be modified as appropriate to the activity based costing based cost behavior model and cost volume profit analysis model, and an optimal pricing decision model is really a product pricing decision model constructed by following the economic principle of maximizing profit.展开更多
Based on the theory of activity-based costing and the idea of value chain,activity optimization and cost control are carried out on the whole construction process of agricultural water conservancy projects. Through th...Based on the theory of activity-based costing and the idea of value chain,activity optimization and cost control are carried out on the whole construction process of agricultural water conservancy projects. Through the use of literature review,case analysis and statistical analysis and other methods,with agricultural water conservancy projects as the research object,and comparing activity-based costing with the traditional model of cost accounting,the writer carries out the corresponding value chain analysis,and comes to the following conclusion: the statistical calculation and analysis of the entire construction process based on activity-based costing can accurately and effectively control the costs of water conservancy projects. Through the use of activity-based costing,the cost data of agricultural water conservancy projects is more detailed and accurate,and cost management personnel can also find non-value-added activities,optimize the enterprise's value chain and achieve cost control objectives through the analysis of the activity chain and value chain of agricultural water conservancy projects.展开更多
Along with the product price competition growing intensely, it is apparently important for reasonably distributing and counting cost. But, in sharing indirect cost, traditional cost accounting unveils the limitations ...Along with the product price competition growing intensely, it is apparently important for reasonably distributing and counting cost. But, in sharing indirect cost, traditional cost accounting unveils the limitations increasingly, especially in authenticity of cost information. And the accounting theory circles and industry circles begin seeking one kind of new accurate cost calculation method, and the activity based cost (ABC) method emerges as the times require. In this paper, we will build its mathematical model by the basic principle of ABC, and will improve its mathematical model further. We will establish its comparison mathematical model and make the ABC method go a step further to its practical application.展开更多
Activity based costing (ABC) is a method which can solve many limitations of the traditional cost systems in manufacturing management. In this paper, we investigate how to integrate ABC with workflow technology, and ...Activity based costing (ABC) is a method which can solve many limitations of the traditional cost systems in manufacturing management. In this paper, we investigate how to integrate ABC with workflow technology, and build a workflow meta model supporting ABC. Firstly, the concept and concept model of activity based costing (ABC) are introduced. Next, the meta model of P -PROCE (Process, Product, Resource, Organization, and Cost & Evaluation) is presented. Then the cost meta model is defined by adding ABC to P -PROCE model. Object constraint language (OCL) is used to express meta model and constraints. Finally, we show an enterprise modeling and simulation tool based on the workflow meta model. We can systematically construct an enterprise model and easily and efficiently conduct simulation. Moreover it enables us to analyze and evaluate business processes and its costs.展开更多
As a new generation of artificial enzymes,nanozymes show outstanding advantages such as high stability,low cost,and facile synthesis,which endow them with promising applications in biomedical and environmental fields....As a new generation of artificial enzymes,nanozymes show outstanding advantages such as high stability,low cost,and facile synthesis,which endow them with promising applications in biomedical and environmental fields.Among the various reported nanozymes,metal-organic frameworks(MOFs)could mimic the active center of natural enzymes and provide a hydrophobic environment,which makes MOFs attractive alternatives to natural enzymes.Owing to the highly structural diversity and tailorability of MOFs,rational design will contribute to improve the activity of MOF-based nanozymes and promote their potential applications in both biomedical and environmental fields.Therefore,a comprehensiye suminary of activity regulatory strategies of MOF-based nanozymes is urgently needed.Firstly,we summarized the activity regulatory strategies of MOFs with intrinsic enzyme-like activities via modulation of metal nodes,ligands,structures and morphologies.Then the applications of MOF-based nanozymes in biosensing,hazardous degradation,antibacterial,and cancer therapy were also introduced.Finally,the current challenges and future perspectives were discussed in depth.It is highly expected that this review will provide a better understanding on the rational design of novel high-performance MOF-based nanozymes.展开更多
The study examines the extent of adoption of Activity Based Costing （ABC） among naanufacturing companies in Nigeria. The primary data were sourced through questionnaires administered to the Management Accountants of...The study examines the extent of adoption of Activity Based Costing （ABC） among naanufacturing companies in Nigeria. The primary data were sourced through questionnaires administered to the Management Accountants of 40 selected manufacturing companies in South Western part of Nigeria. Descriptive statistics was employed to analyze the data. The study reveals that inability of the traditional cost systems to provide relevant cost was the most highly ranked reason in their decision to adopt ABC. Traditional methods of allocating overhead were therefore believed to be deficient in terms of improving global competitiveness. Also, 60% of the respondents have adopted ABC due to increased ranges of products, competition and increased overhead. Familiarity with and adoption of ABC was found to be across the manufacturing, more than half of the sample are familiar with it. The 40% of respondents who have not adopted ABC cited the cost and complexity involved with implementation as the main reason in non-adoption. However, cost of implementing ABC was enormous which hinder the small scale manufacturing from adopting it. This result may reflect the fact that larger firms are more likely to have the diverse mix of products or services that makes the use of ABC advantages. Consequently, the study recommends that the companies who have not adopted ABC because of its high cost of implementation should endeavor to consider its adoption because in the long run the benefits derive from it will outweigh its cost. It helps to identify inefficient products, departments and activities and helps to allocate more resources on profitable products. In conclusion, the senior management should also give their utmost support to the implementation and success of ABC.展开更多
As plant develops, many industries＇ automatic level is very high leading to the increasing of indirect cost. Traditional costing methods, which use single standard of distributing indirect cost, cannot calculate cus-...As plant develops, many industries＇ automatic level is very high leading to the increasing of indirect cost. Traditional costing methods, which use single standard of distributing indirect cost, cannot calculate cus- tomer cost accurately and satisfy managers any more. This paper is aimed on solving the aforesaid problem. In this paper we propose the thought of evaluating customer cost by using activity based costing（ABC） and the tra- ditional model of customer lifetime value（CLV） to improve the CLV model, then analyze the difference of using both models through an empirical study. As a result, ABC can account customer cost more accurately so that the CLV can help managers evaluate customer more effectively.展开更多
In medical diagnosis, the problem of class imbalance is popular. Though there are abundant unlabeled data, it is very difficult and expensive to get labeled ones. In this paper, an ensemble-based active learning algor...In medical diagnosis, the problem of class imbalance is popular. Though there are abundant unlabeled data, it is very difficult and expensive to get labeled ones. In this paper, an ensemble-based active learning algorithm is proposed to address the class imbalance problem. The artificial data are created according to the distribution of the training dataset to make the ensemble diverse, and the random subspace re-sampling method is used to reduce the data dimension. In selecting member classifiers based on misclassification cost estimation, the minority class is assigned with higher weights for misclassification costs, while each testing sample has a variable penalty factor to induce the ensemble to correct current error. In our experiments with UCI disease datasets, instead of classification accuracy, F-value and G-means are used as the evaluation rule. Compared with other ensemble methods, our method shows best performance, and needs less labeled samples.展开更多
Although SiO_(2)-based anode is a strong competitor to supersede graphite anode for lithium-ion batteries,it still has problems such as low electrochemical activity, enormous loss of active lithium, and serious volume...Although SiO_(2)-based anode is a strong competitor to supersede graphite anode for lithium-ion batteries,it still has problems such as low electrochemical activity, enormous loss of active lithium, and serious volume expansion. In order to solve these problems, we used a graphene network loaded with cobalt metal nanoparticles(rGO-Co) to coat SiO_(2) porous hollow spheres(SiO_(2)@rGO-Co). The construction of porous hollow structure and graphene network can shorten the lithium-ion(Li^(+)) diffusion distance and enhance the conductivity of the composite, which improves the electrochemical activity of SiO_(2) effectively. They also alleviate the volume expansion of the anode in the cycling process. Moreover,nano-scale cobalt metal particles dispersed on graphene catalyze the conversion reaction of SiO_(2) and activate the locked Li+in Li_(2)O through a reversible reaction, which improves the charge and discharge capacity of the anode. The capacity of SiO_(2)@rGO-Co reaches 370.4 m Ah/g after 100 cycles at 0.1 A/g,which is 6.19 times the capacity of pure SiO_(2)(59.8 mAh/g) under the same circumstance. What is more,its structure also exhibits excellent cycle stability, with a volume expansion rate of only 13.0% after 100 cycles at a current density of 0.1 A/g.展开更多
Ag3PO4 is found to be a highly efficient photocatalyst and receives great attention. The high activity of the photocatalyst is credited to the intrinsic electronic structure. The morphology control and nano-composite ...Ag3PO4 is found to be a highly efficient photocatalyst and receives great attention. The high activity of the photocatalyst is credited to the intrinsic electronic structure. The morphology control and nano-composite fabrication are used to improve the performance and practicability. This paper reviews the structure, properties and some theoretical aspects of Ag3PO4 single crystal. Also, the major strategies, namely the morphology control and hetero-nanostructure construction, as ways to improve the performance of Ag3PO4-based photocatalysts, are summarized with the aid of some typical instances.展开更多
Resource-constrained project scheduling problem（RCPSP） is an important problem in research on project management. But there has been little attention paid to the objective of minimizing activities＇ cost with the re...Resource-constrained project scheduling problem（RCPSP） is an important problem in research on project management. But there has been little attention paid to the objective of minimizing activities＇ cost with the resource constraints that is a critical sub-problem in partner selection of construction supply chain management because the capacities of the renewable resources supplied by the partners will effect on the project scheduling. Its mathematic model is presented firstly, and analysis on the characteristic of the problem shows that the objective function is non-regular and the problem is NP-complete following which the basic idea for solution is clarified. Based on a definition of preposing activity cost matrix, a heuristic algorithm is brought forward. Analyses on the complexity of the heuristics and the result of numerical studies show that the heuristic algorithm is feasible and relatively effective.展开更多
The problem of guaranteed cost active fault-tolerant controller （AFTC） design for networked control systems （NCSs） with both packet dropout and transmission delay is studied in this paper. Considering the packet d...The problem of guaranteed cost active fault-tolerant controller （AFTC） design for networked control systems （NCSs） with both packet dropout and transmission delay is studied in this paper. Considering the packet dropout and transmission delay, a piecewise constant controller is adopted. With a guaranteed cost function, optimal controllers whose number is equal to the number of actuators are designed, and the design process is formulated as a convex optimal problem that can be solved by existing software. The control strategy is proposed as follows： when actuator failures appear, the fault detection and isolation unit sends out the information to the controller choosing strategy, and then the optimal stabilizing controller with the smallest guaranteed cost value is chosen. Two illustrative examples are given to demonstrate the effectiveness of the proposed approach. By comparing with the existing methods, it can be seen that our method has a better performance.展开更多
Cycling is an eco-friendly method of transport and recreation. With the intent of reducing the energy cost of cycling without providing an additional energy source, we have proposed the use of a torsion spring for kne...Cycling is an eco-friendly method of transport and recreation. With the intent of reducing the energy cost of cycling without providing an additional energy source, we have proposed the use of a torsion spring for knee-extension support. We developed an exoskeleton prototype using a crossing four-bar mechanism as a knee joint with an embedded torsion spring. This study evaluates the passive knee exoskeleton using constant-power cycling tests performed by eight healthy male participants. We recorded the surface electromyography over the rectus femoris muscles of both legs, while the participants cycled at 200 and 225 W on a trainer with the developed wheel-accelerating system. We then analyzed these data in time-frequency via a continuous wavelet transform. At the same cycling speed and leg cadence, the median power spectral frequency of the electromyography increases with cycling load. At the same cycling load, the median power spectral frequency decreases when cycling with the exoskeleton. Quadriceps activity can be relieved despite the exoskeleton consuming no electrical energy and not delivering net-positive mechanical work. This fundamental can be applied to the further development of wearable devices for cycling assistance.展开更多
This paper puts forward a model of Pearl River Delta (PRD) fishery in the South China Sea (SCS) that integrates the ecological, social and economic costs and benefits of fisheries activities in a multidisciplinary fra...This paper puts forward a model of Pearl River Delta (PRD) fishery in the South China Sea (SCS) that integrates the ecological, social and economic costs and benefits of fisheries activities in a multidisciplinary framework. In particular, an integrated ECOST model is composed of links between an ecological model constructed by Ecopath with Ecosim (EwE) software and a region Social Accounting Matrix (SAM). Then the costs and benefits of five fishing methods are compared from economic, ecological and social three dimensions base on the ECOST model. The potential effects of fishing effort reduction on fishing communication are explored by a series of dynamic simulations for a 10-year period. Key results from prediction (2005-2015) and policy simulations illustrate that fisheries of PRE are geared toward short-term economic profits at the expense of ecological gains and the whole group of societal benefits associated with fishing. However, the status quo can be improved to better levels by reducing fishing efforts.展开更多
Formaldehyde(HCHO)is a common indoor pollutant that is detrimental to human health.Its efficient removal has become an urgent demand to reduce the public health risk.In this work,Ag-MnO_(x)-based catalysts were prepar...Formaldehyde(HCHO)is a common indoor pollutant that is detrimental to human health.Its efficient removal has become an urgent demand to reduce the public health risk.In this work,Ag-MnO_(x)-based catalysts were prepared and activated under different atmosphere(i.e.,air,hydrogen(H_(2))and carbon monoxide(CO))for efficient oxidation of HCHO.The catalyst activated with CO(Ag/Mn-CO)displayed the highest activity among the tested samples with 90% conversion at 100℃ under a gas space velocity of 75,000 mL/(g_(cat)·hr).Complementary characterizations demonstrate that CO reduction treatment resulted in synergically regulated content of surface oxygen on support to adsorb/activate HCHO and size of Ag particle to dissociate oxygen to oxidize the adsorbed HCHO.In contrast,other catalysts lack for either abundant surface oxygen species or metallic silver with the appropriate particle size,so that the integrate activity is limited by one specific reaction step.This study contributes to elucidating the mechanisms regulating the oxidation activity of Ag-based catalysts.展开更多
In this paper we investigate a variant of the scheduling problem on two uniform machines with speeds 1 and s. For this problem, we are given two potential uniform machines to process a sequence of independent jobs. Ma...In this paper we investigate a variant of the scheduling problem on two uniform machines with speeds 1 and s. For this problem, we are given two potential uniform machines to process a sequence of independent jobs. Machines need to be activated before starting to process, and each machine activated incurs a fixed machine activation cost. No machines are initially activated, and when a job is revealed, the algorithm has the option to activate new machines. The objective is to minimize the sum of the makespan and the machine activation cost. We design optimal online algorithms with competitive ratio of (2s+1)/(s+1) for every s≥1.展开更多
In this study,we report the expression of human thyroid peroxidase（TPO） in silkworm larvae and Pichia pastoris GS115. Recombinant TPO is sequentially purified from the hemolymph of infected silkworm larvae and yeast...In this study,we report the expression of human thyroid peroxidase（TPO） in silkworm larvae and Pichia pastoris GS115. Recombinant TPO is sequentially purified from the hemolymph of infected silkworm larvae and yeast using a Ni-NTA resin kit. The concentration of yield of recombinant TPO is 4.87 mg per thousand larvae and 40.83 mg per liter yeast culture. However,the recombinant TPO produced in silkworm show similar binding ability with the specific anti-TPO serum to standard human TPO purified from insect cells. The lower antigen activity indicates the TPO expressed in yeast is not suitable to be used as the coating antigen in enzyme linked immunosorbent assay（ELISA）. The cost of TPO expressed in B. mori is about 1/4 that of in insect cells,and the cost of TPO purified from silkworm for ELISA is only 1/8 that of TPO produced from Sf9 cells. It indicates the Bm NPV-silkworm expression system is a cost-effectiv e platform for producing TPO with high antigen activity.展开更多
Introduction:Myopia has emerged as a major public health challenge affecting the visual health of children and adolescents in China.While evidence confirms the effectiveness of outdoor activity in preventing myopia,co...Introduction:Myopia has emerged as a major public health challenge affecting the visual health of children and adolescents in China.While evidence confirms the effectiveness of outdoor activity in preventing myopia,comprehensive economic analyses of its role in mitigating myopia-related diseases remain limited.Methods:This study employed a microsimulation model to evaluate the cost-effectiveness of increasing outdoor activity across different educational stages—primary,middle,and high school—for myopia prevention in China.The model simulated myopia progression among individuals aged 6 to 18 years,with the intervention defined as an additional 40 minutes of daily outdoor activity.Outcomes measured included changes in myopia prevalence,quality-adjusted life years(QALYs),and associated medical costs.Results:All intervention scenarios proved costeffective,except for those targeting only the high school stage.Interventions focused on primary schools and combined primary–middle school stages not only improved health outcomes but also reduced medical costs.While the all-stages intervention yielded the greatest health benefits,its higher implementation costs make it more suitable for regions with greater resources.Conclusion:These findings highlight the critical importance of early intervention in myopia prevention.Policymakers should prioritize outdoor activity programs at the primary school level and develop tailored prevention strategies based on local resource availability.This study provides empirical evidence for developing scientifically sound,cost-effective myopia prevention strategies for children and adolescents,with relevant implications for other developing countries facing a high myopia burden.展开更多
Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span...Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Based Income Generating Activities (NIGAs) to improve livelihoods while at </span><span style="font-family:Verdana;">the same time enhancing biodiversity conservation in degrading</span><span style="font-family:Verdana;"> agro-ecologies. These activities can diversify and increase famers’ incomes and support in</span><span style="font-family:Verdana;">stinctive biota and fauna resilience. However, evidence to showcase and compare their long-term benefits is scant. We use the case of Uluguru</span><span style="font-family:Verdana;"> Mountains in Tanzania to evaluate and compare viability of agroforestry and beekeeping projects using the Cost</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Benefit Analysis (CBA) approach. The results of analysis yielded positive NPVs for both agroforestry and beekeeping projects at discount rates not higher than 8.2% and 8.5% respectively. Overall, the comparison of economic viability between agroforestry and beekeeping projects revealed that the former was relatively more profitable than the later in terms of both the NPV and Benefit</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Cost Ratio (BCR) criteria. However, the Internal Rate of Return (IRR) for beekeeping was slightly higher than that of agroforestry. Yet, we underscore the fact that these two projects can jointly be implemented to enhance livelihoods of farmers and support biodiversity conservation in the study </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">area </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">and other parts with similar agro-ecologies in developing countries. However, farmers in these agro-ecologies need to be supported by governments and non-government development partners in terms of training and inspiration to shift from orthodox farming to sustainable NIGAs.展开更多
文摘In order to find out the applicability of the optimal pricing decision model based on conventional cost behavior model after activity based costing has given strong shock to the conventional cost behavior model and its assumptions, detailed analyses have been made using the activity based cost behavior and cost volume profit analysis model, and it is concluded from these analyses that the theory behind the construction of optimal pricing decision model is still tenable under activity based costing, but the conventional optimal pricing decision model must be modified as appropriate to the activity based costing based cost behavior model and cost volume profit analysis model, and an optimal pricing decision model is really a product pricing decision model constructed by following the economic principle of maximizing profit.
文摘Based on the theory of activity-based costing and the idea of value chain,activity optimization and cost control are carried out on the whole construction process of agricultural water conservancy projects. Through the use of literature review,case analysis and statistical analysis and other methods,with agricultural water conservancy projects as the research object,and comparing activity-based costing with the traditional model of cost accounting,the writer carries out the corresponding value chain analysis,and comes to the following conclusion: the statistical calculation and analysis of the entire construction process based on activity-based costing can accurately and effectively control the costs of water conservancy projects. Through the use of activity-based costing,the cost data of agricultural water conservancy projects is more detailed and accurate,and cost management personnel can also find non-value-added activities,optimize the enterprise's value chain and achieve cost control objectives through the analysis of the activity chain and value chain of agricultural water conservancy projects.
文摘Along with the product price competition growing intensely, it is apparently important for reasonably distributing and counting cost. But, in sharing indirect cost, traditional cost accounting unveils the limitations increasingly, especially in authenticity of cost information. And the accounting theory circles and industry circles begin seeking one kind of new accurate cost calculation method, and the activity based cost (ABC) method emerges as the times require. In this paper, we will build its mathematical model by the basic principle of ABC, and will improve its mathematical model further. We will establish its comparison mathematical model and make the ABC method go a step further to its practical application.
文摘Activity based costing (ABC) is a method which can solve many limitations of the traditional cost systems in manufacturing management. In this paper, we investigate how to integrate ABC with workflow technology, and build a workflow meta model supporting ABC. Firstly, the concept and concept model of activity based costing (ABC) are introduced. Next, the meta model of P -PROCE (Process, Product, Resource, Organization, and Cost & Evaluation) is presented. Then the cost meta model is defined by adding ABC to P -PROCE model. Object constraint language (OCL) is used to express meta model and constraints. Finally, we show an enterprise modeling and simulation tool based on the workflow meta model. We can systematically construct an enterprise model and easily and efficiently conduct simulation. Moreover it enables us to analyze and evaluate business processes and its costs.
基金financially supported by the National Natural Science Foundation of China(Nos.31901000 and 22022609)the Natural Science Foundation of Jiangsu Higher Education Institutes of China(No.19KJA610003)+1 种基金the Postdoctoral Science Foundation of Jiangsu Province(No.2019K152)the Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions。
文摘As a new generation of artificial enzymes,nanozymes show outstanding advantages such as high stability,low cost,and facile synthesis,which endow them with promising applications in biomedical and environmental fields.Among the various reported nanozymes,metal-organic frameworks(MOFs)could mimic the active center of natural enzymes and provide a hydrophobic environment,which makes MOFs attractive alternatives to natural enzymes.Owing to the highly structural diversity and tailorability of MOFs,rational design will contribute to improve the activity of MOF-based nanozymes and promote their potential applications in both biomedical and environmental fields.Therefore,a comprehensiye suminary of activity regulatory strategies of MOF-based nanozymes is urgently needed.Firstly,we summarized the activity regulatory strategies of MOFs with intrinsic enzyme-like activities via modulation of metal nodes,ligands,structures and morphologies.Then the applications of MOF-based nanozymes in biosensing,hazardous degradation,antibacterial,and cancer therapy were also introduced.Finally,the current challenges and future perspectives were discussed in depth.It is highly expected that this review will provide a better understanding on the rational design of novel high-performance MOF-based nanozymes.
文摘The study examines the extent of adoption of Activity Based Costing （ABC） among naanufacturing companies in Nigeria. The primary data were sourced through questionnaires administered to the Management Accountants of 40 selected manufacturing companies in South Western part of Nigeria. Descriptive statistics was employed to analyze the data. The study reveals that inability of the traditional cost systems to provide relevant cost was the most highly ranked reason in their decision to adopt ABC. Traditional methods of allocating overhead were therefore believed to be deficient in terms of improving global competitiveness. Also, 60% of the respondents have adopted ABC due to increased ranges of products, competition and increased overhead. Familiarity with and adoption of ABC was found to be across the manufacturing, more than half of the sample are familiar with it. The 40% of respondents who have not adopted ABC cited the cost and complexity involved with implementation as the main reason in non-adoption. However, cost of implementing ABC was enormous which hinder the small scale manufacturing from adopting it. This result may reflect the fact that larger firms are more likely to have the diverse mix of products or services that makes the use of ABC advantages. Consequently, the study recommends that the companies who have not adopted ABC because of its high cost of implementation should endeavor to consider its adoption because in the long run the benefits derive from it will outweigh its cost. It helps to identify inefficient products, departments and activities and helps to allocate more resources on profitable products. In conclusion, the senior management should also give their utmost support to the implementation and success of ABC.
基金supported by National Natural Science Fund under Grant No.71201125National Social Science Fund under Grant No.09CJY038+2 种基金General Humanities Social Science Research Program of Ministry of Education under Grant No.10XJC630002Project of Soft Science of Shaanxi Province under Grant No.2009KRM073Humanities Social Science and Management Perking Fund of Northwest Polytechnical University under Grant No.RW201208
文摘As plant develops, many industries＇ automatic level is very high leading to the increasing of indirect cost. Traditional costing methods, which use single standard of distributing indirect cost, cannot calculate cus- tomer cost accurately and satisfy managers any more. This paper is aimed on solving the aforesaid problem. In this paper we propose the thought of evaluating customer cost by using activity based costing（ABC） and the tra- ditional model of customer lifetime value（CLV） to improve the CLV model, then analyze the difference of using both models through an empirical study. As a result, ABC can account customer cost more accurately so that the CLV can help managers evaluate customer more effectively.
文摘In medical diagnosis, the problem of class imbalance is popular. Though there are abundant unlabeled data, it is very difficult and expensive to get labeled ones. In this paper, an ensemble-based active learning algorithm is proposed to address the class imbalance problem. The artificial data are created according to the distribution of the training dataset to make the ensemble diverse, and the random subspace re-sampling method is used to reduce the data dimension. In selecting member classifiers based on misclassification cost estimation, the minority class is assigned with higher weights for misclassification costs, while each testing sample has a variable penalty factor to induce the ensemble to correct current error. In our experiments with UCI disease datasets, instead of classification accuracy, F-value and G-means are used as the evaluation rule. Compared with other ensemble methods, our method shows best performance, and needs less labeled samples.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.52073212,51772205,51772208)the General Program of Municipal Natural Science Foundation of Tianjin(Nos.17JCYBJC17000,17JCYBJC22700)。
文摘Although SiO_(2)-based anode is a strong competitor to supersede graphite anode for lithium-ion batteries,it still has problems such as low electrochemical activity, enormous loss of active lithium, and serious volume expansion. In order to solve these problems, we used a graphene network loaded with cobalt metal nanoparticles(rGO-Co) to coat SiO_(2) porous hollow spheres(SiO_(2)@rGO-Co). The construction of porous hollow structure and graphene network can shorten the lithium-ion(Li^(+)) diffusion distance and enhance the conductivity of the composite, which improves the electrochemical activity of SiO_(2) effectively. They also alleviate the volume expansion of the anode in the cycling process. Moreover,nano-scale cobalt metal particles dispersed on graphene catalyze the conversion reaction of SiO_(2) and activate the locked Li+in Li_(2)O through a reversible reaction, which improves the charge and discharge capacity of the anode. The capacity of SiO_(2)@rGO-Co reaches 370.4 m Ah/g after 100 cycles at 0.1 A/g,which is 6.19 times the capacity of pure SiO_(2)(59.8 mAh/g) under the same circumstance. What is more,its structure also exhibits excellent cycle stability, with a volume expansion rate of only 13.0% after 100 cycles at a current density of 0.1 A/g.
文摘Ag3PO4 is found to be a highly efficient photocatalyst and receives great attention. The high activity of the photocatalyst is credited to the intrinsic electronic structure. The morphology control and nano-composite fabrication are used to improve the performance and practicability. This paper reviews the structure, properties and some theoretical aspects of Ag3PO4 single crystal. Also, the major strategies, namely the morphology control and hetero-nanostructure construction, as ways to improve the performance of Ag3PO4-based photocatalysts, are summarized with the aid of some typical instances.
文摘Resource-constrained project scheduling problem（RCPSP） is an important problem in research on project management. But there has been little attention paid to the objective of minimizing activities＇ cost with the resource constraints that is a critical sub-problem in partner selection of construction supply chain management because the capacities of the renewable resources supplied by the partners will effect on the project scheduling. Its mathematic model is presented firstly, and analysis on the characteristic of the problem shows that the objective function is non-regular and the problem is NP-complete following which the basic idea for solution is clarified. Based on a definition of preposing activity cost matrix, a heuristic algorithm is brought forward. Analyses on the complexity of the heuristics and the result of numerical studies show that the heuristic algorithm is feasible and relatively effective.
基金supported by National Outstanding Youth Foundation (No. 60525303)National Natural Science Foundation of China(No. 60704009)+1 种基金Key Project for Natural Science Research of Hebei Education Department (No. ZD200908)the Doctor Fund of YanShan University (No. B203)
文摘The problem of guaranteed cost active fault-tolerant controller （AFTC） design for networked control systems （NCSs） with both packet dropout and transmission delay is studied in this paper. Considering the packet dropout and transmission delay, a piecewise constant controller is adopted. With a guaranteed cost function, optimal controllers whose number is equal to the number of actuators are designed, and the design process is formulated as a convex optimal problem that can be solved by existing software. The control strategy is proposed as follows： when actuator failures appear, the fault detection and isolation unit sends out the information to the controller choosing strategy, and then the optimal stabilizing controller with the smallest guaranteed cost value is chosen. Two illustrative examples are given to demonstrate the effectiveness of the proposed approach. By comparing with the existing methods, it can be seen that our method has a better performance.
文摘Cycling is an eco-friendly method of transport and recreation. With the intent of reducing the energy cost of cycling without providing an additional energy source, we have proposed the use of a torsion spring for knee-extension support. We developed an exoskeleton prototype using a crossing four-bar mechanism as a knee joint with an embedded torsion spring. This study evaluates the passive knee exoskeleton using constant-power cycling tests performed by eight healthy male participants. We recorded the surface electromyography over the rectus femoris muscles of both legs, while the participants cycled at 200 and 225 W on a trainer with the developed wheel-accelerating system. We then analyzed these data in time-frequency via a continuous wavelet transform. At the same cycling speed and leg cadence, the median power spectral frequency of the electromyography increases with cycling load. At the same cycling load, the median power spectral frequency decreases when cycling with the exoskeleton. Quadriceps activity can be relieved despite the exoskeleton consuming no electrical energy and not delivering net-positive mechanical work. This fundamental can be applied to the further development of wearable devices for cycling assistance.
文摘This paper puts forward a model of Pearl River Delta (PRD) fishery in the South China Sea (SCS) that integrates the ecological, social and economic costs and benefits of fisheries activities in a multidisciplinary framework. In particular, an integrated ECOST model is composed of links between an ecological model constructed by Ecopath with Ecosim (EwE) software and a region Social Accounting Matrix (SAM). Then the costs and benefits of five fishing methods are compared from economic, ecological and social three dimensions base on the ECOST model. The potential effects of fishing effort reduction on fishing communication are explored by a series of dynamic simulations for a 10-year period. Key results from prediction (2005-2015) and policy simulations illustrate that fisheries of PRE are geared toward short-term economic profits at the expense of ecological gains and the whole group of societal benefits associated with fishing. However, the status quo can be improved to better levels by reducing fishing efforts.
基金supported by the National Natural Science Foundation of China(Nos.22025604,22106171,21936005,and 21976196)the Jinan“20 Universities”Funding Project(No.2020GXRC027)。
文摘Formaldehyde(HCHO)is a common indoor pollutant that is detrimental to human health.Its efficient removal has become an urgent demand to reduce the public health risk.In this work,Ag-MnO_(x)-based catalysts were prepared and activated under different atmosphere(i.e.,air,hydrogen(H_(2))and carbon monoxide(CO))for efficient oxidation of HCHO.The catalyst activated with CO(Ag/Mn-CO)displayed the highest activity among the tested samples with 90% conversion at 100℃ under a gas space velocity of 75,000 mL/(g_(cat)·hr).Complementary characterizations demonstrate that CO reduction treatment resulted in synergically regulated content of surface oxygen on support to adsorb/activate HCHO and size of Ag particle to dissociate oxygen to oxidize the adsorbed HCHO.In contrast,other catalysts lack for either abundant surface oxygen species or metallic silver with the appropriate particle size,so that the integrate activity is limited by one specific reaction step.This study contributes to elucidating the mechanisms regulating the oxidation activity of Ag-based catalysts.
基金Project (No. Y605316) supported by the Natural Science Foundationof Zhejiang Province, China and the Natural Science Foundation of the Education Department of Zhejiang Province (No. 20060578), China
文摘In this paper we investigate a variant of the scheduling problem on two uniform machines with speeds 1 and s. For this problem, we are given two potential uniform machines to process a sequence of independent jobs. Machines need to be activated before starting to process, and each machine activated incurs a fixed machine activation cost. No machines are initially activated, and when a job is revealed, the algorithm has the option to activate new machines. The objective is to minimize the sum of the makespan and the machine activation cost. We design optimal online algorithms with competitive ratio of (2s+1)/(s+1) for every s≥1.
基金Supported by the National Natural Science Foundation of China(31372381)Henan Science and Technology Innovation Team of Insect Bio-reactor Fund(C20140047)Henan Natural Science Foundation Project(132300413214.0)
文摘In this study,we report the expression of human thyroid peroxidase（TPO） in silkworm larvae and Pichia pastoris GS115. Recombinant TPO is sequentially purified from the hemolymph of infected silkworm larvae and yeast using a Ni-NTA resin kit. The concentration of yield of recombinant TPO is 4.87 mg per thousand larvae and 40.83 mg per liter yeast culture. However,the recombinant TPO produced in silkworm show similar binding ability with the specific anti-TPO serum to standard human TPO purified from insect cells. The lower antigen activity indicates the TPO expressed in yeast is not suitable to be used as the coating antigen in enzyme linked immunosorbent assay（ELISA）. The cost of TPO expressed in B. mori is about 1/4 that of in insect cells,and the cost of TPO purified from silkworm for ELISA is only 1/8 that of TPO produced from Sf9 cells. It indicates the Bm NPV-silkworm expression system is a cost-effectiv e platform for producing TPO with high antigen activity.
基金supported by the National Natural Science Foundation of China(72293585,72404183).
文摘Introduction:Myopia has emerged as a major public health challenge affecting the visual health of children and adolescents in China.While evidence confirms the effectiveness of outdoor activity in preventing myopia,comprehensive economic analyses of its role in mitigating myopia-related diseases remain limited.Methods:This study employed a microsimulation model to evaluate the cost-effectiveness of increasing outdoor activity across different educational stages—primary,middle,and high school—for myopia prevention in China.The model simulated myopia progression among individuals aged 6 to 18 years,with the intervention defined as an additional 40 minutes of daily outdoor activity.Outcomes measured included changes in myopia prevalence,quality-adjusted life years(QALYs),and associated medical costs.Results:All intervention scenarios proved costeffective,except for those targeting only the high school stage.Interventions focused on primary schools and combined primary–middle school stages not only improved health outcomes but also reduced medical costs.While the all-stages intervention yielded the greatest health benefits,its higher implementation costs make it more suitable for regions with greater resources.Conclusion:These findings highlight the critical importance of early intervention in myopia prevention.Policymakers should prioritize outdoor activity programs at the primary school level and develop tailored prevention strategies based on local resource availability.This study provides empirical evidence for developing scientifically sound,cost-effective myopia prevention strategies for children and adolescents,with relevant implications for other developing countries facing a high myopia burden.
文摘Agroforestry and beekeeping are widely promoted as prospective Nature-</span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Based Income Generating Activities (NIGAs) to improve livelihoods while at </span><span style="font-family:Verdana;">the same time enhancing biodiversity conservation in degrading</span><span style="font-family:Verdana;"> agro-ecologies. These activities can diversify and increase famers’ incomes and support in</span><span style="font-family:Verdana;">stinctive biota and fauna resilience. However, evidence to showcase and compare their long-term benefits is scant. We use the case of Uluguru</span><span style="font-family:Verdana;"> Mountains in Tanzania to evaluate and compare viability of agroforestry and beekeeping projects using the Cost</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Benefit Analysis (CBA) approach. The results of analysis yielded positive NPVs for both agroforestry and beekeeping projects at discount rates not higher than 8.2% and 8.5% respectively. Overall, the comparison of economic viability between agroforestry and beekeeping projects revealed that the former was relatively more profitable than the later in terms of both the NPV and Benefit</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Cost Ratio (BCR) criteria. However, the Internal Rate of Return (IRR) for beekeeping was slightly higher than that of agroforestry. Yet, we underscore the fact that these two projects can jointly be implemented to enhance livelihoods of farmers and support biodiversity conservation in the study </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">area </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">and other parts with similar agro-ecologies in developing countries. However, farmers in these agro-ecologies need to be supported by governments and non-government development partners in terms of training and inspiration to shift from orthodox farming to sustainable NIGAs.
