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Laws of Heat Radiation from Surfaces and Gas Volumes

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World Journal of Engineering and Technology 2015年第4期3卷 260-270页

作者： Anatoliy Nikolaevich Makarov Tver State technical university Tver Russia

It is proven that the law of radiation from solid bodies, Stefan-Boltzmann law shall not be used to calculate heat radiation from gas volumes which are formed in fuel flaring. The determining influence on heat fluxes density of the torch to the heating surfaces has not only a temperature, but power, dimensions, geometrical position of radiative gas volumes. The laws of radiation from gas volumes disclosed in 2001 and the method for calculating heating fluxes from gas volumes, developed on its basis, which takes into account the radiation from full set of particles in gas volume are stated. The torch model in the form of radiative gas volume is used to calculate heat transfer in torch heating furnaces, steam boiler boxes, turbogas unit combustors. The disclosure has enabled us to create new furnaces, fire boxes, combustion chambers, enhance unit performance, and decrease fuel rate, pollutant emissions.

关键词： Disclosure Heat Radiation Torch Fire Box Furnace Combustion Chamber Steam Boiler Turbogas Unit

MOBILE PHONE AS PERVASIVE ELECTRONIC MEDIA TO RECORD AND EVALUATE HUMAN GAIT BEHAVIOR

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Journal of Innovative Optical Health Sciences 2012年第1期5卷 28-35页

作者： QIAN WANG YANG YU YONGQIANG LV JING LIU Department of Biomedical Engineering School of Medicine Tsinghua UniversityBeijing 100084P.R.China technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 P.R.China

Gait recognition has been of great importance for disease diagnosis,rehabilitation assessment,as well as personal *** gait analysis generally has to rely heavily on complex,expensive data acquisition and computing *** significantly simplify the evaluation process the mobile phone,which is one of the most indispensable electronic media in human daily life,was adopted as a pervasive tool for gait study,by using its digital imaging recording and analysis *** basic procedure to record and quantify the video of human gait was illustrated and demonstrated through conceptual *** applications were *** fundamental and practical issues raised in such flexible technology were pointed *** method is expected to be widely used in future human analysis.

关键词： Gait analysis telemedicine pervasive medicine low cost medicine

Portfolio selection: a fuzzy-ANP approach

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Financial Innovation 2020年第1期6卷 313-346页

作者： Masoud Rahiminezhad Galankashi Farimah Mokhatab Rafiei Maryam Ghezelbash Department of Industrial Engineering Tarbiat Modares UniversityTehranIran Department of Industrial Mechanical and Aerospace EngineeringBuein Zahra Technical UniversityBuein ZahraQazvinIran

This study developed specific criteria and a fuzzy analytic network process(FANP)to assess and select portfolios on the Tehran Stock Exchange(TSE).Although the portfolio selection problem has been widely investigated,most studies have focused on income and risk as the main decision-making ***,there are many other important criteria that have been *** fill this gap,first,a literature review was conducted to determine the main criteria for portfolio selection,and a Likert-type questionnaire was then used to finalize a list of ***,the finalized criteria were applied in an FANP to rank 10 different TSE *** results indicated that profitability,growth,market,and risk are the most important criteria for portfolio ***,portfolios 6,7,2,4,8,1,5,3,9,and 10(A6,A7,A2,A4,A8,A1,A5,A3,A9,and A10)were found to be the best *** and directions for future research are discussed.

关键词： Portfolio selection Financial engineering Fuzzy analytic network process(FANP) Multiple-criteria decision-making(MCDM)

Impact of glacier changes and permafrost distribution on debris flows in Badswat and Shishkat catchments,Northern Pakistan

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Journal of Mountain Science 2023年第12期20卷 3687-3702页

作者： HASSAN Wajid SU Feng-huan LIU Wei-ming HASSAN Javed HASSAN Muzammil BAZAI Nazir Ahmed WANG Hao YANG Ze-wen ALI Muzaffar CASTELLANOS Daniel Garcia Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China China-Pakistan Joint Research Center on Earth Sciences CAS-HECIslamabad 45320Pakistan university of Chinese Academy of Sciences Beijing 100049China DTU Space Technical University of DenmarkKongens Lyngby 2800Denmark Department of Environmental Science Karakoram International UniversityGilgit-Baltistan 15100Pakistan Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Instituto de Ciencias de la Tierra Jaume Almera ICTJA-CSICSoléi Sabarís s/nBarcelona 08028Spain

Knowledge of glacier changes and associated hazards is of great importance for the safety consideration of the population and infrastructure in the mountainous regions of Upper Indus Basin(UIB).In this study,we assessed the variations in glacier velocity,glacier surface elevation change,meteorological conditions,and permafrost distribution in Badswat and Shishkat catchments located in UIB to access the potential impact on the occurrence of debris flow in both *** find that the glacier surface velocity increased during the debris flow event in the Badswat catchment and the mean daily temperature was 3.7℃to 3.9℃higher in most of the *** enhanced glacier surface elevation lowering period coincide with the rise in temperature during spring and autumn months between 2015 to 2019 in Badswat *** source region of debris flow falls within the lower boundary of permafrost occurrence zone and lies below the 0℃isotherm during late spring and summer *** Shishkat catchment the 0℃isotherm reaches above the debris flow source area during August and the glacier do not show any significant variations in velocity and surface elevation *** debris flow source area is adjacent to the slow-moving rock glacier in Shishkat catchment while in Badswat catchment the debris flow initiated from the former glacier *** catchments are largely glacierized and thus sensitive to changes in climatic conditions and changes in the cryosphere response possess significant threats to the population *** monitoring of cryosphere-climate change in the region can contribute toward the improvement of disaster risk reduction and mitigation policies.

关键词： Cryosphere change Climate change Debris flow Remote sensing Permafrost Cryosphere hazard

The Development of Hi-Speed Punching System Using A Couple of Rotating Bodies

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厦门大学学报（自然科学版） 2002年第S1期41卷 116-117页

作者： Shinichi Taya Keiichi Shimizu technical Research Lab. Toyo Kohan Co.Technical Research Lab. Toyo Kohan Co. LTD JapanLTD Japan

Punched steel sheets (metal sheets or foils) as thi n as 0.1mm are quite useful in the field of filters and various precision instrume nts. Thus, we have to develop more accurate and speedy techniques for punching t hin sheets. The traditional punching method uses an up-down pressing motion of a punch or a die on a strip of metal. The efficiency of this method is determine d by the speed of the motion. In the case of punching a sequence of tiny holes w ith a few millimeters’ interval, the speed of feeding a strip of metal to the p unching machine cannot exceed only a couple of meters per minute. We have de veloped a new technique for punching tiny holes with a pair of rotating bodies i n order to increase the feeding speed up to 100 meters per minute. Our proposed technique is shown in Fig.1 where the female tool has a round blade and the male tool has an M-shape boss. In addition, the setting of two tools i s alternating. The interference between them cannot occur because the clearance between the front and the back edge of the male tool and the female tool in the rotating direction becomes infinite in this configuration. An appropriate cleara nce is given for the thickness of the sheet between the side edge of the male to ol and the female tool. The punching itself is done by shearing. The side edge o f the male tool does contact with the female tool, but they cannot be interferin g. Our technique has another advantage to the traditional up-down pressing mach ine where the stamped out chips are hard to be discharged. It is quite easy in o ur proposed technique. Fig.2, 3 show a sample of punched material [TPP116A,+39mm88mm,Y,PZ#]Fig.1 The configuration of the punching parts using the sequential punching system.[TPP116B,+43mm155mm,X,BP#]Fig.2 A sample of punched material using the continuous punch ing lineFig.3 A exterior picture of a piece of punched steel foil(coi l) using the continuous punching For our developed high speed punching system, it is shown for (1) th

关键词： The Development of Hi-Speed Punching System Using A Couple of Rotating Bodies

Assessment of prediction performances of stochastic models:Monthly groundwater level prediction in Southern Italy

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Journal of Groundwater Science and Engineering 2021年第2期9卷 161-170页

作者： O Boulariah PA Mikhailov A Longobardi AN Elizariev SG Aksenov Department of Civil Engineering University of SalernoVia Giovanni Paolo II12384084Italy Ufa State Aviation technical university 450000Russian Federation

Stochastic modelling of hydrological time series with insufficient length and data gaps is a serious challenge since these problems significantly affect the reliability of statistical models predicting and forecasting *** this paper,we proposed a method for searching the seasonal autoregressive integrated moving average(SARIMA)model parameters to predict the behavior of groundwater time series affected by the issues *** on the analysis of statistical indices,8 stations among 44 available within the Campania region(Italy)have been selected as the highest quality *** SARIMA models,with different autoregressive,moving average and differentiation orders had been *** reviewing the criteria used to determine the consistency and goodness-of-fit of the model,it is revealed that the model with specific combination of parameters,SARIMA(0,1,3)(0,1,2)_(12),has a high R^(2) value,larger than 92%,for each of the 8 selected *** same model has also good performances for what concern the forecasting skills,with an average NSE of about 96%.Therefore,this study has the potential to provide a new horizon for the simulation and reconstruction of groundwater time series within the investigated area.

关键词： Groundwater level forecast Stochastic modelling Southern Italy Seasonality Homogeneity

Evaporative Cooling Applied in Thermal Power Plants:A Review of the State-ofthe-Art and Typical Case Studies

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Fluid Dynamics & Materials Processing 2023年第9期19卷 2229-2265页

作者： Tiantian Liu Huimin Pang Suoying He Bin Zhao Zhiyu Zhang Jucheng Wang Zhilan Liu Xiang Huang Yuetao Shi Ming Gao Shandong Engineering Laboratory for High-Efficiency Energy Conservation and Energy Storage Technology&Equipment School of Energy and Power EngineeringShandong UniversityJinan250061China College of Energy and Power Engineering Changsha University of Science&TechnologyChangsha410114China technical Research and Development Department Shandong Taiwang Cooling Equipment Co.Ltd.Xintai271221China Shandong Key Laboratory of Key Technology of Tire Mould Himile Mechanical Science and Technology(Shandong)Co.Ltd.Weifang261550China School of Urban Planning and Municipal Engineering Xi’an Polytechnic UniversityXi’an710048China

A review is conducted about the application of the evaporative cooling technology in thermal power *** case studies are considered,namely,evaporative air conditioners,evaporative cooling in direct air-cooled systems,gas turbine inlet cooling,wet cooling towers,and hybrid cooling towers with a crosswind *** effort is provided to describe the advantages related to direct evaporative cooling when it is applied in thermal power plants and illustrate the research gaps,which have not been filled *** particular,typical case studies are intentionally used to compare the cooling performances when direct evaporative cooling is implemented in different types of cooling towers,including the natural draft wet cooling tower(NDWCT)and the pre-cooled natural draft dry cooling tower(NDDCT).It is shown that the NDWCT provides the best cooling performance in terms of power station cooling,followed by the pre-cooled NDDCT,and the NDDCT;moreover,the evaporative pre-cooling is able to enhance the cooling performance of ***,on a yearly basis,better NDDCT cooling performances can be obtained by means of a spray-based pre-cooling approach with respect to wet media ***,the use of nozzle spray is suggested for improvement in the performance of indirect/direct air-cooling systems with controlled water consumption.

关键词： Direct evaporative cooling cooling tower cooling performance wet media nozzle spray thermal power plants

Wood waste biochar promoted anaerobic digestion of food waste:focusing on the characteristics of biochar and microbial community analysis

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Biochar 2022年第1期4卷 152-163页

作者： Chao Zhang Rui Yang Meichen Sun Shicheng Zhang Mingjing He Daniel C.W.Tsang Gang Luo Department of Environmental Science&Engneering Shanghai Key Lab Atmospher Particle Pollution&PreventionFudan UniversityShanghai 200438People’s Republic of China Shanghai technical Service Platform for Pollution Control and Resource Utilization of Organic Waste Shanghai 200438People’s Republic of China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092People’s Republic of China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Research Institute for Future Food The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Anaerobic digestion(AD)has been considered as a promising technique for food waste(FW)***,the accumulation of volatile fatty acids(VFAs)restricts the stability of anaerobic *** present study investigated the use of biochar produced at different conditions(750℃-30 min,750℃-60 min,750℃-120 min,550℃-60 min,650℃-60 min,850℃-60 min,950℃-60 min)for enhancing the AD of *** experiments showed that all the biochar increased the methane production rates and biochar obtained at 750℃-60 min resulted in the highest enhance-ment by 21.5%.It was further showed surface oxygen-containing functional groups and graphitization degree of biochar were the critical factors for improving methane *** analysis showed that biochar addi-tion formed different microbial communities,and Methanosaeta,Romboutsia,and norank_f_Anaerolineaceae were enriched,which might be correlated with direct interspecies electron transfer(DIET).This research showed biochar could enhance the AD of FW and also revealed the main characteristics of biochar relating with the enhancement of AD.

关键词： Anaerobic digestion Food waste Wood waste biochar Methane production Sustainable waste management

搅拌摩擦焊工艺参数对2024-T351铝合金搭接焊接头成形质量和力学性能的影响(英文)

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Transactions of Nonferrous Metals Society of China 2013年第12期23卷 3525-3539页

作者： I.RADISAVLJEVIC A.ZIVKOVIC N.RADOVIC V.GRABULOV Military technical Institute GOSA FOM Faculty of Technology and Metallurgy University of Belgrade Institute for Materials testing

研究搅拌摩擦焊时R/v比对2024-T351铝合金焊接质量的影响。搅拌摩擦焊时搅拌针的旋转速度设定为750、950和1180 r/min，焊接速度在73~190 mm/min内变化，对应的R/v比在5.00~10.27内。采用各种无损（外观检测、X射线检测）和有损（金相... 详细信息

研究搅拌摩擦焊时R/v比对2024-T351铝合金焊接质量的影响。搅拌摩擦焊时搅拌针的旋转速度设定为750、950和1180 r/min，焊接速度在73~190 mm/min内变化，对应的R/v比在5.00~10.27内。采用各种无损（外观检测、X射线检测）和有损（金相观察、拉伸实验和硬度测量）检测手段对焊接试样进行分析。在所有的试样中，搅拌摩擦焊中各种典型的区域都有存在，不同的区域其晶粒尺寸不同。接头的拉伸性能为基材的52.2%~82.3%。在R/v比为8.06，10.17和10.27时焊接质量最佳。其原因是在最佳搅拌速度下，材料围绕搅拌针充分流动，从而能够填充其中产生的空隙，阻止空洞的生成。结果还表明，R/v 比对接头的硬度分布、洋葱样形状、裂纹的萌生和扩展都有影响。

关键词： 2024铝合金搅拌摩擦焊焊接参数热量输入焊接质量