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Petroleum 2021年第4期7卷 407-413页

作者： Md Nahin Mahmood Boyun Guo Department of Petroleum and Mining Engineering Chittagong University of Engineering&TechnologyChattogram4349Bangladesh Department of Petroleum Engineering University of LouisianaLafayetteLA70504USA

Development of marine gas hydrate resources presents a huge challenge to the energy industry owing to the well production complications such as wellbore collapse,sand production,and low productivity.Radial lateral wells(RLW)and horizontal snake wells(HSW)have been proposed separately to mitigate these complications.We compare the productivity potentials of these two types of wells using the recently developed analytical models and field case data from a gas hydrate reservoir in the South China Sea.It is concluded that RLW will yield slightly higher gas productivity than HSW under similar conditions.Sensitivity analysis with the well models indicates that the productivity of RLW is directly proportional to the number of laterals,length of laterals,and radius of laterals,while the productivity of HSW is directly proportional to the length and radius of the horizontal wellbore.The decision of using RLW or HSW can be made based on economic analysis of well completion and production,which should be addressed in future studies.

关键词： Natural gas hydrate Radial lateral wells Horizontal snake wells productivity

Environmental heterogeneity and productivity drive the assemblage of benthic diatom:a case study of the Three Gorges Reservoir

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Journal of Oceanology and Limnology 2023年第3期41卷 991-1006页

作者： Songqi YANG Tian OUYANG Shaojun XU Lu ZHAO Lulu JI Junqiong SHI Zhongxing WU Key Laboratory of Eco-environments in Three Gorges Reservoir Region(Ministry of Education) Chongqing Key Laboratory of Plant Ecology and Resources Research in Three Gorges Reservoir RegionSchool of Life ScienceSouthwest UniversityChongqing 400715China Gansu Microalgae Technology Innovation Center Zhangye 734000China College of Horticulture and Plant Protection Henan University of science and TechnologyLuoyang 471000China

Dam construction has a critical effect on river ecosystems in the world,resulting in a rapid decline in biodiversity and ecosystem health.However,the effect of dam construction on the assemblage pattern of benthic diatoms remains unclear.The benthic diatoms assemblages in the tributary backwater area of the Three Gorges Reservoir(TGR)were investigated under low water level(LWL)and high water level(HWL)conditions.Results show that Discostella stelligera,Nitzschia palea,and Craticula subminuscula were dominant species in LWL,while Achnanthidium minutissimum and Nitzschia dissipata were dominant in HWL.Furthermore,environmental variables,productivity parameters,diversity indices,and community similarity were found significantly different between LWL and HWL periods.The Mantel test indicated that both environmental and spatial factors had significant effects on diatom communities in backwater area,while productivity was also a key driving force in LWL.The variation partitioning analysis(VPA)further demonstrated that environment factors could explain the largest variance of diatom assemblages in HWL(9%)and LWL(11%),followed by spatial factors.The relative importance of productivity to diatom community was significantly enhanced in LWL,but only a slight effect was found in HWL.These results indicate that the diatom assemblages were shaped by both environmental filtering and spatial factors.The relative importance of spatial factors depended on the degree of productivity.Therefore,the homogenization of diatom communities due to environmental disturbance,e.***.eutrophication and dam building,is the underlying mechanism in assembling the benthic diatoms.

关键词： Three Gorges Reservoir benthic diatom assemblage environmental heterogeneity productivity

productivity and Export Performance: Micro-Level Evidence from the Manufacturing Sector in Nigeria

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2019年第3期14卷 428-460页

作者： Kanang Amos Akims Dianah Mukwate Ngui Department of Economics University of JosJos 930001Nigeria School of Economies Kenyatta UniversityNairobiKenya

This paper investigates how productivity influences firms' exports.Various finn characteristics are employed to test the self-selection hypothesis alongside the effects of firms' productivity on their share of exports in total sales.Using a pseudo-panel data set constructed from the firm-level data for the manufacturing sector in Nigeria,we find no evidence that higher productivity influences the decision on whether or not a firm would participate in exports.However,it is established that higher productivity increases the share of exports in total sales of firms that are already participating in foreign markets.A policy implication of our result is that Nigeria can realize a larger share of manufactured exports in total merchandise exports by directing efforts towards improving primarily the productivity of firms that are already involved in exports.

关键词： productivity self-selection export performance manufacturing sector

Adoption determinants of improved management practices and productivity in pond polyculture of carp in Bangladesh

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Aquaculture and Fisheries 2023年第1期8卷 96-101页

作者： Md Sadique Rahman Mohammad Mizanul Haque Kazal Shah Johir Rayhan Shirajum Manjira Department of Management and Finance Sher-e-Bangla Agricultural UniversitySher-e-Bangla NagarDhaka1207Bangladesh Department of Development and Poverty Studies Sher-e-Bangla Agricultural UniversitySher-e-Bangla NagarDhaka1207Bangladesh

Adopting improved management practices for rearing carp can play a vital role in developing the aquaculture sector of Bangladesh.This study identifies the factors that facilitate the adoption of improved management practices and their relationship with productivity.Primary data was collected from 300 carp farmers through face-to-face interviews.Improved management practices were divided into three categories:simple,intermediate and complex.Findings indicated that high adopters(those who adopted at least one simple,one intermediate and one complex practice)were only around 10%of respondents.The adoption of improved management practices was influenced by spousal education level,training,extension contact,and off-farm income sources.productivity of high adopters was 38%higher than that of non-adopters.Policy implications from this research included improving extension facilities from public agencies to facilitate adoption of improved practices and to increase and sustain productivity in carp farming.Modifying the current extension approach and diversifying income sources among farmers will facilitate widespread adoption of improved management practices.

关键词： Adoption Aquaculture Extension Ordered probit productivity

Political uncertainty,leadership and productivity

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Economic and Political Studies 2022年第3期10卷 314-326页

作者： Chunxia Jiang Yun Zhu Business School University of AberdeenAberdeenUK The Peter J.Tobin College of Business St.John’s UniversityQueensNYUSA

We investigate the impact of political uncertainty in the context of the upper echelon theory.Using provincial-level data of polit-ical leaders in China over the period 1995–2015,we take a two-step approach to first examine the impact of top leader teams’(TLTs)traits on productivity and,second,to test if such leadership effects vary with political uncertainty.We find that TLTs’educa-tion,generally a driving force behind productivity,is less effective during the period of high political uncertainty.TLTs’work experi-ence positively contributes to productivity,which is strengthened under high political uncertainty.TLTs’career ambition leads to higher productivity,but such an effect attenuates when political uncertainty is high.Finally,TLTs’political positions negatively con-tribute to productivity and the effect is barely affected by political uncertainty,suggesting a disconnection between political posi-tions and economic outcomes.

关键词： Political uncertainty leadership productivity

Engineering a New Chloroplastic Photorespiratory Bypass to In crease Photosynthetic Efficiency and productivity in Rice

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Molecular Plant 2019年第2期12卷 199-214页

作者： Bo-Ran Shen Li-Min Wang Xiu-Ling Lin Zhen Yao Hua-Wei Xu Cheng-Hua Zhu Hai-Yan Teng Li-Li Cui E.-E. Liu Jian-Jun Zhang Zheng-Hui He Xin-Xiang Peng State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources College of Life Sciences South China Agricultural University Guangzhou 510642 China College of Agricultural Henan University of Science and Technology Luoyang Henan China Departme nt of Biology San Fran cisco State University San Fran cisco CA USA These authors contributed equally to this article.

Over the past few years, three photorespiratory bypasses have been introduced into plants, two of which led to observable in creases in photos yn thesis and biomass yield. However, most of the experiments were carried out using Arabidopsis under controlled environmental conditions, and the increases were only observed under low-light and short-day conditions. In this study, we designed a new photorespiratory bypass (called GOC bypass), characterized by no reducing equivalents being produced during a complete oxidation of glycolate into CO2 catalyzed by three rice-self-originating enzymes, i.e., glycolate oxidase, oxalate oxidase, and catalase. We successfully established this bypass in rice chloroplasts using a multi-gene assembly and transformation system. Transgenic rice plants carrying GOC bypass (GOC plants) showed significant increases in photosynthesis efficiency, biomass yield, and nitrogen content, as well as several other CO2-enriched phe no types under both greenhouse and field conditions .Grain yield of GOC plants varied depending on seeding season and was increased significantly in the spring. We further demonstrated that GOC plants had significant advantages under high-light conditions and that the improvements in GOC plants resulted primarily from a photosynthetic CO2-concentrating effect rather than from improved energy balance. Taken together, our results reveal that engineering a newly designed chloroplastic photorespiratory bypass could increase photosynthetic efficiency and yield of rice plants grown in field conditions, particularly under high light.

关键词： photorespiratory bypass photosynthetic efficiency productivity rice

Habitat productivity is a poor predictor of body size in rodents

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Current Zoology 2020年第2期66卷 135-143页

作者： Bader H.Alhajeri Lucas M.V.Porto Renan Maestri Department of Biological Sciences Kuwait UniversitySafat13060Kuwait Department of Ecology Universidade Federal do Rio Grande do SulPorto AlegreRS91501-970Brazil

The"resource availability hypothesis"predicts occurrence of larger rodents in more productive habitats.This prediction was tested in a dataset of 1,301 rodent species.We used adult body mass as a measure of body size and normalized difference vegetation index(NDVI)as a measure of habitat productivity.We utilized a cross-species approach to investigate the association between these variables.This was done at both the order level(Rodentia)and at narrower taxonomic scales.We applied phylogenetic generalized least squares(PGLS)to correct for phylogenetic relationships.The relationship between body mas and NDVI was also investigated across rodent assemblages.We controlled for spatial autocorrelation using generalized least squares(GLS)analysis.The cross-species approach found extremely low support for the resource availability hypothesis.This was reflected by a weak positive association between body mass and NDVI at the order level.We find a positive association in only a minority of rodent subtaxa.The best fit GLS model detected no significant association between body mass and NDVI across assemblages.Thus,our results do not support the view that resource availability plays a major role in explaining geographic variation in rodent body size.

关键词： Bergmann's rule body size(body mass) habitat productivity heat conservation hypothesis normalized difference vegetation index(NDVI) resource availability hypothesis

productivity Gains from Offshore Outsourcing： Evidence from the Chinese Manufacturing Industry

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China & World Economy 2015年第5期23卷 104-122页

作者： Junli Zhao Vigdis Boasson Associate Professor Glorious Sun School of Business and Management Donghua University Shanghai China. Associate Professor Department of Finance and Law Central Michigan University Michigan USA.

Using the Cobb-Douglas production function and vertical specialization share, the present paper measures the productivity spillover effects of offshore outsourcing in the Chinese manufacturing industry. We examine different production factors and the degree of openness by dividing the Chinese manufacturing industry into five major categories： capital-intensive business, technological-intensive business, labor-intensive business, open business and non-open business. The results show that offshore outsourcing is positively associated with productivity in the Chinese manufacturing industry as a whole, but less so in labor-intensive industries and more in capital-intensive industries. Moreover, the positive impact of outsourcing on productivity is slightly higher in open industries than in non-open industries. These results shed light on the differential spillover effects of offshore outsourcing on productivity. Our findings suggest that outsourcing structure is important to China＇s long- run competitive advantage. China ＇ s policy-makers should encourage further offshore capital- intensive and technology-intensive activities and focus more on outward-oriented offshore businesses.

关键词： Chinese manufacturing outsourcing productivity spillovers vertical disintegration

The Measurement of the Software Ecosystem’s productivity with GitHub

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Computer Systems Science & Engineering 2021年第1期36卷 239-258页

作者： Zhifang Liao Yiqi Zhao Shengzong Liu Yan Zhang Limin Liu Jun Long School of Computer Science and Engineering Central South UniversityChangsha410075China School of Information Technology and Management Hunan University of Finance and EconomicsChangsha410075China Department of Computing School of ComputingEngineering and Built EnvironmentGlasgow Caledonian UniversityGlasgowG40BAUK

Software productivity has always been one of the most critical metrics for measuring software development.However,with the open-source community(e.g.,GitHub),new software development models are emerging.The traditional productivity metrics do not provide a comprehensive measure of the new software development models.Therefore,it is necessary to build a productivity measurement model of open source software ecosystem suitable for the open-source community’s production activities.Based on the natural ecosystem,this paper proposes concepts related to the productivity of open source software ecosystems,analyses influencing factors of open source software ecosystem productivity,and constructs a measurement model using these factors.Model validation experiments show that the model is compatible with a large portion of open source software ecosystems in GitHub.This study can provide references for participants of the open-source software ecosystem to choose proper types of ecosystems.The study also provides a basis for ecosystem health assessment for researchers interested in ecosystem quality.

关键词： Software ecosystem open-source software ecosystem OSSECO productivity productivity model

Analyzing COVID-19 Impact on the Researchers productivity through Their Perceptions

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Computers, Materials & Continua 2021年第5期67卷 1835-1847页

作者： Syeda Javeria Shoukat Humaira Afzal Muhammad Rafiq Mufti Muhammad Khalid Sohail Dost Muhammad Khan Nadeem Akhtar Shahid Hussain Mansoor Ahmed Department of Computer Science COMSATS UniversityIslamabad45550Pakistan Department of Computer Science Bahauddin Zakariya UniversityMultan60800Pakistan Department of Computer Science COMSATS University IslamabadVehari CampusIslamabad61100Pakistan Department of Management Studies Bahria Business SchoolBahria UniversityIslamabad44000Pakistan Department of Computer Science&IT The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Computer and Information Science University of OregonEugeneOR97401USA

Context:Since the end of 2019,the COVID-19 pandemic had a worst impact on world’s economy,healthcare,and education.There are several aspects where the impact of COVID-19 could be visualized.Among these,one aspect is the productivity of researcher,which plays a significant role in the success of an organization.Problem:There are several factors that could be aligned with the researcher’s productivity of each domain and whose analysis through researcher’s feedback could be beneficial for decision makers in terms of their decision making and implementation of mitigation plans for the success of an organization.Method:We perform an empirical study to investigate the substantial impact of COVID-19 on the productivity of researchers by analyzing the relevant factors through their perceptions.Our study aims to find out the impact of COVID-19 on the researcher’s productivity that are working in different fields.In this study,we conduct a questionnaire-based analysis,which included feedback of 152 researchers of certain domains.These researchers are currently involved in different research activities.Subsequently,we perform a statistical analysis to analyze the collected responses and report the findings.Findings:The results indicate the substantial impact of COVID-19 pandemics on the researcher’s productivity in terms of mental disturbance,lack of regular meetings,and field visits for the collection of primary data.Conclusion:Finally,it is concluded that researcher’s daily or weekly meetings with their supervisors and colleagues are necessary to keep them more productive in task completion.These findings would help the decision makers of an organization in the settlement of their plan for the success of an organization.

关键词： COVID-19 researchers productivity statistical analysis