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Ergonomic and efficiency analysis of conventional apple harvest process

International Journal of Agricultural and Biological Engineering 2019年第2期12卷 210-217页

作者： Zhao Zhang Yuanjie Wang Zhaohua Zhang Dapeng Li Zhengze Wu Rui Bai Guangfu Meng Department of Agricultural and Biological Engineering Pennsylvania State UniversityUniversity ParkPA 16802USA Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081China College of Economics and Management Shandong Agricultural UniversityTai’an 271018ShandongChina Shanghai Nuclear Engineering Research and Design Institute Shanghai 200233China Jiana real estate development company Dezhou 253000ShandongChina huafa real estate development company Weihai 264200ShandongChina TianJinXi Railway Station China Railway Beijing Group Co.Ltd.Dezhou 253000ShandongChina

Apples are still manually harvested by workers using ladders and *** it is known that manual apple harvest would probably lead to occupational injuries(e.g.,back,neck,and shoulder strains),there has been little research that focuses on identifying the awkward activities/postures of pickers during the harvest *** categorizing apple harvest work into 12 activities,this study used the method of Rapid Upper Limb Assessment(RULA)to identify awkward postures/activities that occurred during apple *** activities confirmed include descending a ladder,dumping apples,picking high and low apples on a ladder as well as on the ground,and moving a ladder,with potential reasons for each awkward activity ***,it was demonstrated that pickers spent approximately 64%of working time under awkward postures that would lead to occupational *** addition,this study analyzed picker harvest efficiency in terms of general and detail *** general mode assessed harvest activity in terms of picking and non-picking,with results showing that pickers averagely spent 76%(±7%)of harvest time in picking *** analysis evaluated picking activities in terms of reaching,detaching,and transporting apples,with results showing that pickers spent averagely 30%(±6%)of time in detaching apples,which is the value time during apple ***,valuable picking time ratio was obtained as the multiplication of picking time ratio and detaching time *** a valuable ratio of 22%(±5%),it theoretically demonstrated the low harvest efficiency of the traditional harvest *** a majority of the awkward activities and the low efficiency were because of the ladders/buckets,using a harvest-assist unit may be a potential ***,more efforts should be spent on the development of innovative mechanism to replace worker in placing attached apples to the *** the time for transporting apples is eliminated,the time for r

关键词： rapid upper limb assessment awkward postures apple harvest safety ergonomic analysis harvest efficiency analysis

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City positioning theories and city core competencies

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科教文汇 2007年第04S期 142-144页

作者： Xinquan Zhu Shenyang City sets up the real estate development limited company Shen yang Liaoning 110021

City positioning The Chinese city in a decision develops the topic of the *** the 90's of 20 centuries, the economic integral and globalization developed rapidly. The development make national boundary become not so important, the function of the city is increasingly outstanding. In other words, national competition ability is morally now on the city competition ability. At the same time, this development result that the industry is divided internationally and is divided in cities. Therefore, under the condition of globalization, if the city wants the superior development, it must take advantages and avoid shortage, to position the city accurately, establish the competition and development the strategy. The city positioning is clearly defined the city competition ability, more important it indicated the direction of the city development. Trough the analysis of the resource and environment of the city, decide an accurate position of the best function of the city, well configure the inner and outside resource, catch the opportunities, face the challenges, maximized the market share in order to maximized the wealth and city competition ability.

关键词：城市建设城市发展经济增长城市管理

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A study on courtyard apartment types in South Korea from the 1960s to 1970s

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Frontiers of Architectural Research 2017年第2期6卷 149-156页

作者： Namsu Jang Sungil Ham real estate development Marketing Department Tobacco & Ginseng Corporation Seoul 06176 Republic of Korea Interior Architecture and Built Environment Yonsei University Seoul 03722 Republic of Korea

In the 1960s, when apartments were being introduced in South Korea and were not yet standardized, diverse attempts at construction were made. However, due to factors such as the preference for houses that face south, apartment planning principles were unified. The present study intended to find out characteristics that can be applied to the current demands by studying cases of experimental plans among apartments, understanding the plans of courtyard apartments and classifying the cases into different types. The types of 29 courtyard apartments constructed in 1960-1970s in Seoul were analyzed. The apartments were classified into complex types that refer to cases where many buildings form a courtyard, block types, and open types. 2017 Higher Education Press Limited company. Production and hosting by Elsevier B.V. on behalf of KeAi. This is an open access article under the CC BY-NC-ND license

关键词： Courtyard apartment Courtyard collective housing Brock-type collective housing Apartment planning

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碱渣的工程性质及其微结构特征(英文)

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岩土工程学报 1999年第1期21卷 100-103页

作者：李月永闫澍旺张金勇殷校棠天津大学 Tanggu real estate company

目前碱渣已被作为工程回填土用于大面积填垫工程，但是由于其化学成分、形成过程及其微结构的特殊性，其宏观性质与其它天然土相比有明显的不同。本文分析了碱渣的微观结构及其成因，并对碱渣与增钙灰之间的作用机理作了分析。

关键词：碱渣工程性质微结构微观图像增钙灰

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Effect of freeze-thaw cycle on hydraulic conductivity of compacted clayey soil

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Journal of Mountain Science 2022年第2期19卷 606-614页

作者： GUO Lei YU Qi-hao YIN Na ZHANG Dong-ming ZHANG Deng-ping REN Xiu-ling YOU Yan-hui ZHANG Zhen-yu BING Hui CHEN Shi-jie State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Beiluihe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-Environment and ResourceChinese Academy of SciencesLanzhou 730000China Gansu City real estate development CO. Ltd.Lanzhou 730000China Yalong River Hydropower development company Ltd.Chengdu 610051China

When filling embankment dams in cold regions,engineers must solve two freeze–thaw cycle(FTC)-induced soil ***,compacted soil constituting the dam is subjected to the FTC during dam ***,loose soil material(LSM),which is subjected to the FTC,fills the *** investigate the effects of the aforementioned two problems on the hydraulic conductivity of compacted clayey soil,a series of permeation tests on clayey soil compacted before and after FTC were conducted in this *** results showed that for the first problem,the hydraulic conductivity of compacted clayey soil subjected to one FTC significantly increases by two to three orders of magnitude because FTC-induced cracks can cause preferential flow in the permeation *** the second problem,when the FTC number is less than a critical number,the FTC of the LSM may result in the development of united soil particles,thereby increasing the effective porosity ratio and hydraulic conductivity of the compacted *** was discovered that the hydraulic conductivity of compacted soil can increase by one to three times when the LSM is subjected to 10 *** the FTC number exceeds a critical number,the effective porosity ratio and hydraulic conductivity of the compacted soil may decrease with the FTC of the *** should be investigated in future studies,and the results can be used to improve engineering management processes when filling embankment dams during winter in cold regions.

关键词： Permeability Freeze-thaw cycles(FTCs) Effective porosity ratio Embankment dam Cold region

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Schedulability of Fault Tolerant real Time System Based on Local Optimum Checkpoint Under Priority Mixed Strategy

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Chinese Journal of Electronics 2015年第2期24卷 236-244页

作者： HE Zhongzheng MEN Chaoguang CHEN Yongjun LI Xiang Department of Computer Science and Technology Harbin Engineering University China Xinxing Construction and development General company

Against the defect of the real time system fault tolerant model that can only tolerate one fault, the Local optimum checkpoint(LOC) algorithm was *** according to the schedulability analysis, the worst case response time formula under the fault tolerant priority mixed strategy based on the local optimum checkpoint was deduced. Finally the Fault tolerant priority configuration search algorithm under Mixed strategy based on LOC(FTPCS-MS-LOC) was proposed. The FTPCS-MS-LOC can tolerate multiple transient faults. The algorithm can effectively reduce the search space compared to the enumeration method. The simulation shows that the FTPCS-MSLOC can significantly improve the system fault resilience than the fault tolerant priority inheritance, promotion and demotion strategy, and also the mixed strategy based on the checkpoint interval in the condition of single fault occurred.

关键词： real-time systems Rollback recovery Fault tolerant priority Schedulability Checkpoint interval

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Experimental study of chemical concentration variation of ASP flooding

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Science China(Technological Sciences) 2009年第7期52卷 1882-1890页

作者： WANG JiaLu YUAN ShiYi SHI FaShun JIA Xu Research Institute of Petroleum Exploration and development Beijing 100083China PetroChina Limited company Beijing 100011China

A physical modeling system of long slim tube was established. Several pressure measuring and sampling points were laid out at different positions along the tube. Through real-time measurements of pressures and chemical concentrations at different points, the mass transfer and chemical concentration of ASP flooding in porous media are studied. The concentration of chemicals declines gradually during the fluid flow from the inlet to the outlet of the model. The concentration increases in the front edge of the slug faster than the concentration decreases in the rear edge of the slug. The concentration variation of the chemicals is an asymmetrical and offset process. The order of motion velocities of the chemicals from fast to slow is polymer, alkali and surfactant. The motion lag and comprehensive diffusion are strong in the vicinity of the inlet, the motion velocities of the chemicals are high, the difference of flow velocities among the three chemicals is significant and the chromatographic separation of the chemicals is obvious. In the area near the outlet, the comprehensive diffusion and motion lag become weak, the concentrations of the chemicals decrease, the motion velocities of the chemicals are slow, the difference among the motion velocities of the chemicals becomes small, the chromatographic separation is not obvious, the adsorption and retention of chemicals gradually increase as the chemical slug moves further along the tube, the adsorption and retention of polymer is the most serious.

关键词： ASP flooding concentration of chemicals motion velocity chromatographic separation adsorption and retention

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Seismic Sedimentology Interpretation Method of Meandering Fluvial Reservoir:From Model to real Data

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Journal of Earth Science 2015年第4期26卷 598-606页

作者： Tao Zhang Xianguo Zhang Chengyan Lin Jingfeng Yu Shouxiu Zhang College of Earth Science and Engineering Shandong University of Science and Technology School of Geosciences China University of Petroleum Exploration and development Research Institute Xinjiang Oilfield Company Dongxin Oil Production Plant Shengli Oilfield Company

Reservoir architecture of meandering river deposition is complex and traditional seismic facies interpretation method cannot characterize it when layer thickness is under seismic vertical reso- lution. In this study, a seismic sedimentology interpretation method and workflow for point bar char- acterization is built. Firstly, the influences of seismic frequency and sandstone thickness on seismic re- flection are analyzed by outcrop detection with ground penetrating radar （GPR） and seismic forward modeling. It is found that （1） sandstone thickness can influence seismic reflection of point bar architecture. With the increasing of sandstone thickness from 1/4 wavelength （λ） to λ/2, seismic reflection geometries various from ambiguous reflection, ＂V＂ type reflection to ＂X＂ type reflection; （2） seismic frequency can influence reservoirs＇ seismic reflection geometry. Seismic events follow inclined lateral aggradation surfaces, which is isochronic depositional boundaries, in high frequency seismic data while the events extend along lithologic surfaces, which are level, in low frequency data. Secondly, strata slice interpretation method for thin layer depositional characterization is discussed with seismic forward modeling. Lastly, a method and workflow based on the above study is built which includes seismic frequency analysis, 90° phasing, stratal slicing and integrated interpretation of slice and seismic profile. This method is used in real data study in Tiger shoal, the Gulf of Mexico. Two episodes of meandering fluvial deposition is recognized in the study layer. Sandstone of the lower unit, which is formed in low base level stage, distributes limited. Sandstone distribution dimension and channel sinuosity become larger in the upper layer, which is high base level deposition.

关键词： point bar reservoir architecture seismic sedimentology stratal slice.

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Theory on real-time control of construction quality and progress and its application to high arc dam

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Science China(Technological Sciences) 2010年第10期53卷 2611-2618页

作者： ZHONG DengHua1, REN BingYu1, LI MingChao1, WU BinPing1 & LI MingChuan2 1 Department of Hydraulic and Hydroelectric Engineering, School of Civil Engineering, Tianjin University, Tianjin 300072, China 2 Ertan Hydropower development company, Ltd., Chengdu 610051, China Department of Hydraulic and Hydroelectric Engineering School of Civil Engineering Tianjin University Tianjin China Ertan Hydropower development company Ltd. Chengdu China

A complete scheme for solving the key scientific problems associated with high-standard,high-intensity continuous construction of high arch dams was presented. First,based on a coupling analysis of construction system decomposition and coordination for a high arc dam,a mathematical model for real-time control of construction quality and progress that considers complex constraints was developed. Second,a method of progress control was proposed based on a dynamic simulation. Third,a dynamic quality control mechanism was established based on construction information collected using a PDA. Fourth,a system for integrating collected information,progress simulation and quality control analyses under a network environment was developed. Finally,these methods were applied to a practical project to show that each aspect of a construction process can be managed effectively and that real-time monitoring and feedback control can be realized. Our methods provide new theoretical principles and technical measures for quality and progress control in the high arc dam construction process.

关键词： construction quality construction progress dynamic simulation real-time control network high arc dam

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Controllable thermal rectification design for buildings based on phase change composites

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Journal of Semiconductors 2024年第2期45卷 40-45页

作者： Hengbin Ding Xiaoshi Li Tianhang Li Xiaoyong Zhao He Tian School of Integrated Circuits and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084China Zhuhai huafa Properties Co. LtdZhuhai 519030China

Phase-change material(PCM)is widely used in thermal management due to their unique thermal ***,related research in thermal rectifier is mainly focused on exploring the principles at the fundamental device level,which results in a gap to real ***,we propose a controllable thermal rectification design towards building applications through the direct adhesion of composite thermal rectification material(TRM)based on PCM and reduced graphene oxide(rGO)aerogel to ordinary concrete walls(CWs).The design is evaluated in detail by combining experiments and finite element *** is found that,TRM can regulate the temperature difference on both sides of the TRM/CWs system by thermal *** difference in two directions reaches to 13.8 K at the heat flow of 80 W/m^(2).In addition,the larger the change of thermal conductivity before and after phase change of TRM is,the more effective it is for regulating temperature difference in two *** stated technology has a wide range of applications for the thermal energy control in buildings with specific temperature requirements.

关键词： phase change composites controllable thermal rectification building applications

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