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Inequalities relating to L_p-version of Petty's conjectured projection inequality 被引量:1
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作者 王卫东 冷岗松 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第2期269-276,共8页
Petty's conjectured projection inequality is a famous open problem in the theory of convex bodies. In this paper, it is shown that an inequality relating to Lp-version of the Petty's conjectured projection inequalit... Petty's conjectured projection inequality is a famous open problem in the theory of convex bodies. In this paper, it is shown that an inequality relating to Lp-version of the Petty's conjectured projection inequality is developed by using the notions of the Lp-mixed volume and the Lp-dual mixed volume, the relation of the Lp-projection body and the geometric body Г-pK, the Bourgain-Milman inequality and the Lp-Bnsemann-Petty inequality. In addition, for each origin-symmetric convex body, by applying the Jensen inequality and the monotonicity of the geometric body Г-pK, the reverses of Lp-version of the Petty's conjectured projection inequality and the Lp-Petty projection inequality are given, respectively. 展开更多
关键词 Lp-version Petty projection inequality Petty's conjectured projectioninequality Lp-projection body REVERSE
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Construction Project Management and Construction Quality Control Strategy
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作者 Qinrong Zhang 《Journal of Architectural Research and Development》 2024年第4期45-50,共6页
With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction ... With the gradual acceleration of the urbanization process,the construction industry has been developing rapidly.As the key link to ensure the quality and safety of the project,construction management and construction quality control are of great significance to enhance the competitiveness of construction enterprises and realize sustainable development.In this paper,the effective strategy of construction management and the effective strategy of construction quality control will be discussed in depth,aiming at providing useful management and quality control strategies for construction enterprises. 展开更多
关键词 Construction engineering management Construction quality control STRATEGY quality control point
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Problems and Significance of Land Consolidation Projects Quality and Countermeasures 被引量:3
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作者 王晶 韩霁昌 +1 位作者 张扬 魏样 《Agricultural Science & Technology》 CAS 2015年第5期1098-1100,共3页
Land consolidation program would not only increase farmland area, but also improve land quality. With consideration of problems in land consolidation, such as highlighting number and ignoring quality, and compensating... Land consolidation program would not only increase farmland area, but also improve land quality. With consideration of problems in land consolidation, such as highlighting number and ignoring quality, and compensating poor farmlands for occupied highly-qualified farmlands, the research proposed the importance of quality of land consolidation program and the way for improving the quality, in order to draw attention of national land consolidation industry for quality of the program, protect farmlands and crop safety, and advance social stability and harmony. 展开更多
关键词 quality of proiect Land consolidation FARMLAND FARMERS ECOLOGY
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Construction of project quality health monitoring system based on life-cycle theory
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作者 陈彦 成虎 +1 位作者 刘晶 戴洪军 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期508-512,共5页
In order to more effectively assess the health status of a project, the monitoring indices in a project's life cycle are divided into quality index, cost index, time index, satisfaction index, and sustainable develop... In order to more effectively assess the health status of a project, the monitoring indices in a project's life cycle are divided into quality index, cost index, time index, satisfaction index, and sustainable development index. Based on the feature of qualitative and quantitative indices combining, the PCA-PR (principal component analysis and pattern recognition) model is constructed. The model first analyzes the principal components of the life-cycle indices system constructed above, and picks up those principal component indices that can reflect the health status of a project at any time. Then the pattern recognition model is used to study these principal components, which means that the real time health status of the project can be divided into five lamps from a green lamp to a red one and the health status lamp of the project can be recognized by using the PR model and those principal components. Finally, the process is shown with a real example and a conclusion consistent with the actual situation is drawn. So the validity of the index system and the PCA-PR model can be confirmed. 展开更多
关键词 life-cycle theory principal component analysis (PCA) pattern recognition (PR) quality health monitoring
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Projection pursuit cluster model and its application in water quality assessment 被引量:20
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作者 WANGShun-jiu YANGZhi-feng DINGJing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期994-995,共2页
One of the difficulties frequently encountered in water quality assessment is that there are many factors and they cannot be assessed according to one factor, all the effect factors associated with water quality must ... One of the difficulties frequently encountered in water quality assessment is that there are many factors and they cannot be assessed according to one factor, all the effect factors associated with water quality must be used. In order to overcome this issues the projection pursuit principle is introduced into water quality assessment, and projection pursuit cluster(PPC) model is developed in this study. The PPC model makes the transition from high dimension to one-dimension. In other words, based on the PPC model, multifactor problem can be converted to one factor problem. The application of PPC model can be divided into four parts: (1) to estimate projection index function Q(); (2) to find the right projection direction ; (3) to calculate projection characteristic value of the i th sample z-i, and (4) to draw comprehensive analysis on the basis of z-i. On the other hand, the empirical formula of cutoff radius R is developed, which is benefit for the model to be used in practice. Finally, a case study of water quality assessment is proposed in this paper. The results showed that the PPC model is reasonable, and it is more objective and less subjective in water quality assessment. It is a new method for multivariate problem comprehensive analysis. 展开更多
关键词 projection pursuit CLUSTER MODEL water quality assessment
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Application of Projection Pursuit Evaluation Model Based on Real-Coded Accelerating Genetic Algorithm in Evaluating Wetland Soil Quality Variations in the Sanjiang Plain, China 被引量:34
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作者 FUQIANG XIEYONGGANG WEIZIMIN 《Pedosphere》 SCIE CAS CSCD 2003年第3期249-256,共8页
A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded ... A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, China. By adopting the im-proved real-coded accelerating genetic algorithm (RAGA), the projection direction is optimized and multi-dimensional indexes are converted into low-dimensional space. Classification of wetland soils and evaluationof wetland soil quality variations are realized by pursuing optimum projection direction and projection func-tion value. Therefore, by adopting this new method, any possible human interference can be avoided andsound results can be achieved in researching quality changes and classification of wetland soils. 展开更多
关键词 EVALUATION projection pursuit evaluation model real-coded acceleratinggenetic algorithm soil quality variations
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Evolution trend of the water quality in Dongping Lake after South-North Water Transfer Project in China 被引量:2
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作者 HU Zun-fang KANG Feng-xin +4 位作者 ZOU An-de YU Lin-song LI Yang TIAN Tong-liang KANG Gui-ling 《Journal of Groundwater Science and Engineering》 2019年第4期333-339,共7页
To investigate the evolution trend of water quality in Dongping Lake after South-North Water Transfer Project operation as well as to ensure the safe usage of the water receiving areas, water samples were collected an... To investigate the evolution trend of water quality in Dongping Lake after South-North Water Transfer Project operation as well as to ensure the safe usage of the water receiving areas, water samples were collected and determined before and after water delivery in different hydrological seasons. Then, comprehensive pollution index method, comprehensive nutrition state index method and health risk assessment model were utilized to evaluate the quality, nutrition, and health risk of Dongping Lake water. Results showed that the quality of Dongping Lake water still met level Ⅲ (light pollution) no matter before or after water delivery. The nutrition state was improved from light eutropher before water delivery to mesotropher after water delivery. The health risk level was reduced from high-medium before water delivery to medium level after water delivery. In summary, the operation of the eastern route of South-North Water Transfer Project is beneficial for water environment improvement of Dongping Lake. 展开更多
关键词 South-North WATER Transfer project Dongping LAKE WATER quality NUTRITION Health risk
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INEQUALITIES OF THE QUERMASSINTEGRALS FOR THE L_p-PROJECTION BODY AND THE L_p-CENTROID BODY 被引量:2
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作者 王卫东 冷岗松 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期359-368,共10页
Associated with the concepts of the Lp-mixed quermassintegrals, the Lp-mixed volume, and the Lp-dual mixed volume, we establish inequalities for the quermassintegrals of the Lp-projection body and the Lp-centroid body... Associated with the concepts of the Lp-mixed quermassintegrals, the Lp-mixed volume, and the Lp-dual mixed volume, we establish inequalities for the quermassintegrals of the Lp-projection body and the Lp-centroid body. Further, the general results for the Shephard problem of the Lp-projection body and the Lp-centroid body are obtained. 展开更多
关键词 Lp-centroid body Lp-projection body Lp-mixed projection body quer massintegrals shephard problem
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Impact of hydroelectric projects on river environment: Analysis of water quality changes in Ningxia Reach of Yellow River 被引量:2
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作者 Sun Dongpo Lu Ruili +1 位作者 Song Yongjun Yan Jun 《Water Science and Engineering》 EI CAS 2008年第2期66-75,共10页
In this paper, the relationship between hydroelectric projects and the river environment is analyzed. Recently, the large-scale regulation of runoff by large hydroelectric projects in the Ningxia Reach of the Yellow R... In this paper, the relationship between hydroelectric projects and the river environment is analyzed. Recently, the large-scale regulation of runoff by large hydroelectric projects in the Ningxia Reach of the Yellow River has altered natural runoff processes, causing an increase in the probability of low discharge and an overall adjustment of riverbed evolution and river characteristics. During low-flow years, the combined effects of these two changes can weaken the self-purification capacity and reduce the water environmental capacity of the river. This is one of the main reasons for the recent decrease of water quality in the Ningxia Reach. This research shows that it is necessary to implement river training projects to maintain stable flow paths, not only for adjusting river regimes and for flood control, but also for increasing the self-purification capacity and the water environmental capacity of the river. Methods and proposals for coordinating the operation of hydroelectric projects with the protection of the river environment are presented in the interest of promoting sustainable development. 展开更多
关键词 runoff adjustment hydroelectric project self-purification capacity fluvial process water environmental capacity
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Slope excavation quality assessment and excavated volume calculation in hydraulic projects based on laser scanning technology 被引量:5
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作者 Chao Hu Yi-hong Zhou +1 位作者 Chun-ju Zhao Zhi-guo Pan 《Water Science and Engineering》 EI CAS CSCD 2015年第2期164-173,共10页
Slope excavation is one of the most crucial steps in the construction of a hydraulic project. Excavation project quality assessment and excavated volume calculation are critical in construction management. The positio... Slope excavation is one of the most crucial steps in the construction of a hydraulic project. Excavation project quality assessment and excavated volume calculation are critical in construction management. The positioning of excavation projects using traditional instruments is inefficient and may cause error. To improve the efficiency and precision of calculation and assessment, three-dimensional laser scanning technology was used for slope excavation quality assessment. An efficient data acquisition, processing, and management workflow was presented in this study. Based on the quality control indices, including the average gradient, slope toe elevation, and overbreak and underbreak,cross-sectional quality assessment and holistic quality assessment methods were proposed to assess the slope excavation quality with laserscanned data. An algorithm was also presented to calculate the excavated volume with laser-scanned data. A field application and a laboratory experiment were carried out to verify the feasibility of these methods for excavation quality assessment and excavated volume calculation. The results show that the quality assessment indices can be obtained rapidly and accurately with design parameters and scanned data, and the results of holistic quality assessment are consistent with those of cross-sectional quality assessment. In addition, the time consumption in excavation quality assessment with the laser scanning technology can be reduced by 70%e90%, as compared with the traditional method. The excavated volume calculated with the scanned data only slightly differs from measured data, demonstrating the applicability of the excavated volume calculation method presented in this study. 展开更多
关键词 Slope excavation quality assessment Volume calculation Three-dimensional laser scanning technology
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Research on Quality Risk of EPC Hydropower Projects in Vietnam 被引量:1
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作者 Sy Hung Mai Jianqiong Wang 《World Journal of Engineering and Technology》 2017年第2期299-308,共10页
Engineering, procurement and construction (EPC) contracts are on the way to become the most usual form of contracting applied by the private sector to undertake construction works on large scale Hydropower projects. I... Engineering, procurement and construction (EPC) contracts are on the way to become the most usual form of contracting applied by the private sector to undertake construction works on large scale Hydropower projects. If EPC contract management is not implemented and controlled properly. Quality is the first important factor for any contractors who involve in the hydropower project execution. The purpose of this study is to investigate and evaluate risks causing not good quality of EPC hydropower projects in Vietnam. In addition, the study also provided the recommendations for project practitioners to mitigate the impacts of those identified risks. The findings of this study can be a good managerial reference for project management teams who are working in other countries that have similar economic and investment environments to Vietnam to get their EPC construction project completed on quality, thus will ensuring the benefits to the government, the investors, the contractors, and the parties involved. 展开更多
关键词 EPC HYDROPOWER project RISK Analysis and Evaluation RISK Control PREVENT RISKS
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On Reverses of the Lp-petty Projection Inequality 被引量:1
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作者 WANG Wei-dong WEI Dai-jun XIANG Yu 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期491-498,共8页
Lutwak, Yang and Zhang established the Lp-petty projection inequality. In this paper, the several reverses of the Lp-petty projection inequality are shown.
关键词 convex body Lp-projection body Lp-centroid body REVERSE Lp-petty projection inequality
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A continuous quality improvement project to reduce medication error in the emergency department 被引量:1
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作者 Sara BC Lee Larry LY Lee +1 位作者 Richard SD Yeung Jimmy TS Chan 《World Journal of Emergency Medicine》 CAS 2013年第3期179-182,共4页
BACKGROUND:Medication errors are a common source of adverse healthcare incidents particularly in the emergency department(ED) that has a number of factors that make it prone to medication errors.This project aims to r... BACKGROUND:Medication errors are a common source of adverse healthcare incidents particularly in the emergency department(ED) that has a number of factors that make it prone to medication errors.This project aims to reduce medication errors and improve the health and economic outcomes of clinical care in Hong Kong ED.METHODS:In 2009,a task group was formed to identify problems that potentially endanger medication safety and developed strategies to eliminate these problems.RESULTS:Responsible officers were assigned to look after seven error-prone areas.Strategies were proposed,discussed,endorsed and promulgated to eliminate the problems identified.A reduction of medication incidents(Ml) from 16 to 6 was achieved before and after the improvement work.CONCLUSION:This project successfully established a concrete organizational structure to safeguard error-prone areas of medication safety in a sustainable manner. 展开更多
关键词 Medication error Medication safety Continuous quality Improvement(CQI)
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Developing an evidence-based and theory informed intervention to involve families in patients care after surgery: A quality improvement project 被引量:1
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作者 Anne Maria Eskes Anne Marthe Schreuder +2 位作者 Hester Vermeulen Els Jacqueline Maria Nieveen van Dijkum Wendy Chaboyer 《International Journal of Nursing Sciences》 CSCD 2019年第4期352-361,共10页
Objectives: In the post-surgical setting,active involvement of family caregivers has the potential to improve patient outcomes by prevention of surgical complications that are sensitive to fundamental care.This paper ... Objectives: In the post-surgical setting,active involvement of family caregivers has the potential to improve patient outcomes by prevention of surgical complications that are sensitive to fundamental care.This paper describes the development of a theoretically grounded program to enhance the active involvement of family caregivers in fundamental care for post-surgical patients.Methods: We used a quality improvement project following a multi-phase design.In Phase 1,an iterative method was used to combine evidence from a narrative review and professionals' preferences.In Phase 2,the logic model underlying the program was developed guided by four steps: (1) confirm situation,intervention aim,and target population;(2) documented expected outcomes,and outputs of the intervention;(3) identify and describe assumptions,external factors and inputs;and (4) confirm intervention components.Results: Phase 1 identified a minimum set of family involvement activities that were both supported by staff and the narrative review.In Phase 2,the logic model was developed and includes (1) the inputs (e.g.educational-and environmental support),(2) the ultimate outcomes (e.g.reduction of postoperative complications),(3) the intermediate outcomes (e.g.behavioural changes),and (4) immediate outcomes (e.g.improved knowledge,skills and attitude).Conclusions: We demonstrated how we aimed to change our practice to an environment in which family caregivers were stimulated to be actively involved in postoperative care on surgical wards,and how we took different factors into account.The description of this program may provide a solid basis for professionals to implement the family involvement program in their own setting. 展开更多
关键词 Family caregivers Hospital surgery department Nursing care Nursing models quality improvement
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Study of Quality Management in Construction Projects
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作者 Tan Chin-Keng Abdul-Rahman, Hamzah 《Chinese Business Review》 2011年第7期542-552,共11页
This research management, exp and lores preliminarily the practices of quality management, management commitment in quality quality management implementation problems in construction projects in the context of Malaysi... This research management, exp and lores preliminarily the practices of quality management, management commitment in quality quality management implementation problems in construction projects in the context of Malaysian construction industry. The research applies semi-structured interview approach with twelve project management practitioners. The findings of the study indicate that the state of quality management in construction projects in Malaysia needs to be strengthened and there are problems in relation to quality management implementation that require attention and further research. The paper provides an insight on the state of quality management in construction projects in Malaysia. 展开更多
关键词 quality management construction project management PRACTICES management commitment PROBLEMS
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Future changes in precipitation and water availability over the Tibetan Plateau projected by CMIP6 models constrained by climate sensitivity 被引量:1
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作者 Hui Qiu Tianjun Zhou +3 位作者 Liwei Zou Jie Jiang Xiaolong Chen Shuai Hu 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期40-46,共7页
Precipitation projections over the Tibetan Plateau(TP)show diversity among existing studies,partly due to model uncertainty.How to develop a reliable projection remains inconclusive.Here,based on the IPCC AR6–assesse... Precipitation projections over the Tibetan Plateau(TP)show diversity among existing studies,partly due to model uncertainty.How to develop a reliable projection remains inconclusive.Here,based on the IPCC AR6–assessed likely range of equilibrium climate sensitivity(ECS)and the climatological precipitation performance,the authors constrain the CMIP6(phase 6 of the Coupled Model Intercomparison Project)model projection of summer precipitation and water availability over the TP.The best estimates of precipitation changes are 0.24,0.25,and 0.45 mm d^(−1)(5.9%,6.1%,and 11.2%)under the Shared Socioeconomic Pathway(SSP)scenarios of SSP1–2.6,SSP2–4.5,and SSP5–8.5 from 2050–2099 relative to 1965–2014,respectively.The corresponding constrained projections of water availability measured by precipitation minus evaporation(P–E)are 0.10,0.09,and 0.22 mm d^(−1)(5.7%,4.9%,and 13.2%),respectively.The increase of precipitation and P–E projected by the high-ECS models,whose ECS values are higher than the upper limit of the likely range,are about 1.7 times larger than those estimated by constrained projections.Spatially,there is a larger increase in precipitation and P–E over the eastern TP,while the western part shows a relatively weak difference in precipitation and a drier trend in P–E.The wetter TP projected by the high-ECS models resulted from both an approximately 1.2–1.4 times stronger hydrological sensitivity and additional warming of 0.6℃–1.2℃ under all three scenarios during 2050–2099.This study emphasizes that selecting climate models with climate sensitivity within the likely range is crucial to reducing the uncertainty in the projection of TP precipitation and water availability changes. 展开更多
关键词 Tibetan plateau Climate sensitivity Precipitation projection Water availability projection
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Several inequalities for L_2-projection body
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作者 朱先阳 冷岗松 《Journal of Shanghai University(English Edition)》 CAS 2009年第2期108-112,共5页
In this paper, by using the Lp-Brunn-Minkowski theory and its dual theory, L2-version on the conjectured projection inequality is investigated, the (reverse) inclusive relationship between L2-projection body and the... In this paper, by using the Lp-Brunn-Minkowski theory and its dual theory, L2-version on the conjectured projection inequality is investigated, the (reverse) inclusive relationship between L2-projection body and the classical projection body are established, and a constrained minimization problem is solved. 展开更多
关键词 convex body L2-projection body the classical projection body
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A projected gradient method with nonmonotonic backtracking technique for solving convex constrained monotone variational inequality problem
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作者 WANG Yun-juan ZHU De-tong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期463-474,共12页
Based on a differentiable merit function proposed by Taji, et al in “Mathematical Programming, 1993, 58: 369-383”, a projected gradient trust region method for the monotone variational inequality problem with conve... Based on a differentiable merit function proposed by Taji, et al in “Mathematical Programming, 1993, 58: 369-383”, a projected gradient trust region method for the monotone variational inequality problem with convex constraints is presented. Theoretical analysis is given which proves that the proposed algorithm is globally convergent and has a local quadratic convergence rate under some reasonable conditions. The results of numerical experiments are reported to show the effectiveness of the proposed algorithm. 展开更多
关键词 trust region line search projected gradient variational inequality
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Exploring perspectives in assessing the quality of governance of the Reducing Emissions from Deforestation and Forest Degradation (REDD+) pilot project in Cambodia: Use of Q Methodology
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作者 Sareth NHEM Young-jin LEE 《Journal of Mountain Science》 SCIE CSCD 2020年第1期95-116,共22页
Public and policy makers alike are concerned about national and global deforestation and forest degradation. These issues pose a significant threat to social, economic and environmental welfare.Attempts to prevent for... Public and policy makers alike are concerned about national and global deforestation and forest degradation. These issues pose a significant threat to social, economic and environmental welfare.Attempts to prevent forest loss and increased attention to pilot REDD+ projects in community forestry sites would both deliver rural livelihood benefits and help to reduce adverse climate impacts.However, there has been no significant exploration of the viewpoints of local experts to determine the monitoring and action needed to support communitybased forestry and improve the governance of REDD+pilot projects in Cambodia. Therefore, this study aimed to assess the perceptions of local stakeholders towards the quality of governance of the first community forest REDD+ pilot project in Cambodia,employing Q-methodology. We adapted 11 indicators of the hierarchical framework of assessment of governance quality to design 40 Q-statements related to REDD+ governance or achievements. The 52 P-set ranked these Q-statements with respect to the community-based REDD+ pilot project. Our study revealed that local stakeholders held four distinct, and partially opposite, views, that:(1) the REDD+ project is successful because it is inclusiveness and capable of causing behavioral change;(2) REDD+ pilot projects should be led by government, not external or locally;and needs more resources;(3) the REDD+ pilot project has raised unrealistic expectations, would likely be a source of corruption and will probably not be successful for local people or halting deforestation;and(4) the REDD+ pilot project is inclusive but not very transparent and probably ineffective at protecting forest. Through these four varied perspectives from local people involved in the project,we can see that there remain serious challenges to the future of pilot community forestry REDD+ projects,including the complex interaction between the multinational actors and the local socio-ecological systems.To move forwards, this study suggested Cambodia should make a pro-poor REDD+ program,implementing more community-based REDD+projects which explicitly build the assets and capacity of the poorest households. This study also shows that Q-methodology can highlight the diverse viewpoints of local stakeholders concerning the quality of community forest REDD+ governance, helping policy makers, implementers and local stakeholders to better identify the challenges to be addressed. 展开更多
关键词 REDD+ Governance quality INDICATOR Q-METHODOLOGY DEFORESTATION Cambodia
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Quality Guided Phase Unwrapping for Fringe Projection Profilometry 被引量:1
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作者 C.J.Tay 《实验力学》 CSCD 北大核心 2006年第1期71-76,共6页
Fringe projection technique is a non-contact, full field 3-D shape measurement method. The object depth information is recorded in one or several deformed fringe patterns. The phase-shifting algorithm or the Fourier t... Fringe projection technique is a non-contact, full field 3-D shape measurement method. The object depth information is recorded in one or several deformed fringe patterns. The phase-shifting algorithm or the Fourier transform method can be used to extract the wrapped phase data. A phase unwrapping process is then applied to retrieve a continuous phase distribution, which represents the surface profile of the test object. In this paper, a quality-guided phase unwrapping approach is incorporated and two novel phase quality evaluation methods are proposed to facilitate the phase unwrapping process. 展开更多
关键词 相品质 相展开 边缘发射 相移 傅立叶变换
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