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Design and prototyping of the readout electronics for the transition radiation detector in the high energy cosmic radiation detection facility

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Nuclear Science and Techniques 2024年第4期35卷 189-199页

作者： Jie-Yu Zhu Yang-Zhou Su Hai-Bo Yang Fen-Hua Lu Yan Yang Xi-Wen Liu Ping Wei Shu-Cai Wan Hao-Qing Xie Xian-Qin Li Cong Dai Hui-Jun Hu Hong-Bang Liu Shu-Wen Tang Cheng-Xin Zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

The high energy cosmic-radiation detection(herd)facility is planned to launch in 2027 and scheduled to be installed on the China Space Station.It serves as a dark matter particle detector,a cosmic ray instrument,and an observatory for high-energy gamma rays.A transition radiation detector placed on one of its lateral sides serves dual purpose,(ⅰ)calibrating herd's electromagnetic calorimeter in the TeV energy range,and(ⅱ)serving as an independent detector for high-energy gamma rays.In this paper,the prototype readout electronics design of the transition radiation detector is demonstrated,which aims to accurately measure the charge of the anodes using the SAMPA application specific integrated circuit chip.The electronic performance of the prototype system is evaluated in terms of noise,linearity,and resolution.Through the presented design,each electronic channel can achieve a dynamic range of 0–100 fC,the RMS noise level not exceeding 0.15 fC,and the integral nonlinearity was<0.2%.To further verify the readout electronic performance,a joint test with the detector was carried out,and the results show that the prototype system can satisfy the requirements of the detector's scientific goals.

关键词： herd Dark matter particle detection TRD Readout electronics SAMPA Data acquisition Performance test

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Study on temperature response of the herd calorimeter cell

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辐射探测技术与方法(英文) 2023年第2期7卷 227-233页

作者： Yingying Dai Xingzhu Cui Xin Liu Yongwei Dong Hongwei Liang Zhenzhong Zhang Xiaochuan Xia Zhipeng Wei State Key Laboratory of High Power Semiconductor Lasers Changchun University of Science and TechnologyChangchun130022China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing100049China School of Microelectronics Dalian University of TechnologyDalian116024China

Purpose To derive the temperature response of the basic unit of the electromagnetic calorimeter of the high energy cosmic-radiation detection(herd)facility.Method Tested a method to measure herd calorimeter cell(HCC)light yield using an ultraviolet Light-Emitting Diode with a wavelength of 300 nm,and established an experimental setup and tested the light yield of the HCC at different temperatures in a thermal chamber.Results and conclusions The result showed that the signal amplitudes variation of the HCC reached up to 10.2% with temperature ranging from 0 to 60℃,if we narrow the temperature range to 0-35℃,the variation was about 3.7% and it showed much better linearity.This result provides a good instruction on the thermal control of the herd calorimeter(CALO)to improve its performance.

关键词： herd LYSO WLSF Optical output Temperature response

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Enhanced Mask R-CNN for herd segmentation

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International Journal of Agricultural and Biological Engineering 2021年第4期14卷 238-244页

作者： Rotimi-Williams Bello Ahmad Sufril Azlan Mohamed Abdullah Zawawi Talib School of Computer Sciences Universiti Sains Malaysia11800Pulau PinangMalaysia Department of Mathematics/Computer Sciences University of AfricaToru-OruaBayelsa StateNigeria

Livestock image segmentation is an important task in the field of vision and image processing.Since utilizing the concentration of forage in the grazing area with shielding the surrounding farm plants and crops is necessary for making effective cattle ranch arrangements,there is a need for a segmentation method that can handle multiple objects segmentation.Moreover,the indistinct boundaries and irregular shapes of cattle bodies discourage the application of the existing Mask Region-based Convolutional Neural Network(Mask R-CNN)which was primarily modeled for the segmentation of natural images.To address this,an enhanced Mask R-CNN model was proposed for multiple objects instance segmentation to support indistinct boundaries and irregular shapes of cattle bodies for precision livestock farming.The contributions of this method are in multiple folds:1)optimal filter size smaller than a residual network for extracting smaller and composite features;2)region proposals for utilizing multiscale semantic features;3)Mask R-CNN’s fully connected layer integrated with sub-network for an enhanced segmentation.The experiment conducted on pre-processed datasets produced a mean average precision(mAP)of 0.93,which was higher than the results from the existing state-of-the-art models.

关键词： livestock farming image segmentation mask R-CNN herd enhancement

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Study of linearity of LYSO crystal for the high energy cosmic radiation detection(herd)facility

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Radiation Detection Technology and Methods 2017年第1期1卷 21-28页

作者： Zheng Quan Zhigang Wang Ming Xu Yongwei Dong Junjing Wang Guangpeng An Xin Liu Tianwei Bao Li Zhang RuijieWang Junguang Lv Bobing Wu Shuangnan Zhang Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsCASBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsCASBeijing 100049China

The high energy cosmic-radiation detection(herd)facility is a space mission designed for detecting cosmic ray(CR)electrons,γ-rays up to tens of TeV and CR nuclei from proton to iron up to several PeV.The main instrument of herd is a 3-D imaging calorimeter(CALO)composed of nearly ten thousand lutetium yttrium orthosilicate(LYSO,with cerium doping)crystal cubes.A large dynamic range of single herd CALO Cell(HCC)is necessary to achieve herd’s PeV observation objectives,which means that the response of HCC should maintain a good linearity from minimum ionizing particle(MIP)calibration to PeV shower maximum.In order to study the linearity ofHCC over such a large energy range,a beam test has been implemented at the E2 and E3 beam lines of BEPC.High intensity pulsed electron beam provided by E2 line is used for producing high energy density within HCC;π^(+)/proton provided by E3 line are used forHCCcalibration.The results showthat no saturation effect occurs and the linearity ofHCCis better than 10%from 30 MeV(1MIP)to 1.1×10^(3) TeV(energy density is 93 TeV/cm^(3)),which can meet the requirement mentioned above.

关键词： herd Calorimeter LYSO Linearity Beam test

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Validating the Classification of Smallholder Dairy Farming Systems Based on herd Genetic Structure and Access to Breeding Services

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Agricultural Sciences 2017年第7期8卷 545-558页

作者： Solomon Gizaw Megersa Abera Melku Muluye Mohammed Aliy Kefyalew Alemayehu Azage Tegegne International Livestock Research Institute Addis Ababa Ethiopia EjereWoreda Livestock and Fisheries Resource Development Office Addis Alem Ethiopia West Gojam Livestock and Fisheries Resource Development Office Debre Marokos Ethiopia Jimma University College of Agriculture and Veterinary Medicine Jimma Ethiopia Bahir Dar University Bahir Dar Ethiopia

Smallholder dairy farming in Africa is classified into rural, peri-urban and urban systems. The major classification criterion is demographic. Dairy systems are extensively characterized, but not based on rigorous statistical analyses. We validated this classification based on herd genetic structure and identify determinants of within-system variations, taking Ethiopia as a case study. Discriminant function analysis correctly classified 38% - 50.6% of the 360 sampled farms into the three systems. Multinomial logistic regression analysis showed that rural and peri-urban farmers were 1.26 (P herd within systems. In conclusion, considering farms within systems as a uniform unit to target development interventions may not be appropriate and thus farm topologies and system specific determinants of farmers’ breeding strategies need to be considered to design and introduce appropriate breeding interventions.

关键词： Smallholder Dairy Farming Systems Crossbreeding herd Genetic Structure Breeding Services

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Analysis of a predator-prey model with herd behavior and disease in prey incorporating prey refuge

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International Journal of Biomathematics 2019年第1期12卷 133-171页

作者： Sangeeta Saha G.P.Samanta Department of Mathematics Indian Institute of Engineering Science and Technology Shibpur Howrah-711103India

In this work,we have introduced an eco-epidemiological model of an infected predator prey system.Incorporation of prey refuge gives that a fraction of the infected prey is available to the predator for consumption.Moreover,to make the model more realistic to the environment,we have introduced strong Allee effect in the susceptible population.Boundedness and positivity of the solution have been established.Local stability conditions of the equilibrium points have been found with the help of Routh-Hurwitz criterion and it has been observed that if a prey population is infected with a lethal disease,then both the prey(susceptible and infected)and predator cannot survive simultaneously in the system for any parametric values.The disease transmission rate and the attack rate on the susceptible have an important role to control the system dynamics.For different values of these two key parameters,we have got only healthy or disease-free or predation-free or a fluctuating disease-free or even a fluctuating predator-free system with some certain parametric conditions.

关键词： Allee effect herd behavior infected prey refuge extinction bifurcations

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Success Stories in Asia’s Quest for Increasing Its Domestic Milk Production

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Journal of Food Science and Engineering 2018年第2期8卷 74-82页

作者： John Moran Geoff Walker Mohammad Abdus Salam Profitable Dairy Systems Kyabram 3620VictoriaAustralia Land O Lakes DhakaBangladesh Bangladesh Dairy Enhancement Program Bangladesh

Throughout the humid tropics of Asia,smallholder dairy(SHD)farmers have developed their production systems largely based on the“traditional way of doing things”.Tradition is a generic word used in this case to mean basing farm management decisions and practices on how their father,or friends or even next door neighbours do things.The low levels of milk production and herd fertility,the high incidences of calf mortalities and poor animal health(such as lameness and mastitis)and the inferior quality of much of the milk sourced from these farms are clear indications that many of these traditional farm management practices are in urgent need of re-evaluation.This need not necessarily be the norm and this paper provides two good examples of how innovation can pay off in the humid tropics of Bangladesh.They clearly demonstrated that improving herd management,particularly feeding management,can dramatically increase cow performance with higher milk yields and herd fertility.

关键词： Dairy development milk yield herd fertility

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What determine herder households' sustainable grassland management behaviors in western China?

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Ecological Economy 2014年第2期7卷 108-119页

作者： TAN Shu-hao TAN Zhong-chun School of Agricultural Economics and Rural Development Renmin University of China School of Management Science & Industrial Engineering Nanjing University of Finance & Economics

Grassland is most important in China due to its multi-functions. However, about 90% of total usable grassland in China has been degraded and the degradation expands at a rate of 2 million ha per year. Western China covers 6.12 million square kilometers and 63.8% of the total national area with a distribution of 50 minority nationalities and 75% of the minority national population. Ecological environment there is very vulnerable with more than 90% areas of the annually increased degradation taking place. Under the current tenure arrangement, the individual herder households become the main and direct users of grassland, their decision-making on grassland management may have crucial impact on ecological environment as well as their livelihoods. Thus, it is necessary to examine the determinants of their grassland management behaviors. This study applies 231 household field data from 6 provinces of western China and uses econometric models to explore the major constraints for restricting the herd households' grassland management behaviors. Main results show that under the current tenure and other governance measures, institutional factors, market price and herder's farm and household's characteristics affect the grassland management behaviors.

关键词： grassland herd household model institutions land g

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Reproductive Trends in Cebu Cattle Grazing Rice Crop Residues in Colombian Tropical Dry Forest

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Open Journal of Forestry 2013年第4期3卷 7-9页

作者： Elisa Sierra-Montoya Rolando Barahona-Rosales Z. Tatiana Ruíz-Cortés Faculty of Agrarian Sciences Group of Research BIOGéNESIS University of Antioquia Medellin Colombia National University of Colombia Medellín Colombia

The objective of this study was to describe the trend of reproductive performance of primiparous and multiparous cows that grazed rice crop residues located in a Dry Tropical Forest of Colombia, taking into account the rainfall pattern of the place. In this study, 89 primiparous and 309 multiparous Cebu cattle records were analyzed. Mean, mean standard deviation for age at first calving and open days of primipar-ous Cebu cattle were 41.05± 1.85 months and 269.7±36.25 days respectively. Confidence intervals (95%) for both reproductive parameters were 36.8-45.3 months and 202.7-336.6 days respectively. For multiparous Cebu cattle, the mean and mean standard deviation for open days and calving interval were 245.6±36.8 days and 17.5±0.9 months respectively. Confidence intervals 207.1-366.9 days and 13.9-20.7 months respectively. The mean rainfall since 1999 until 2012 was1202 mmper year. The reproduc-tive trend of the primiparous cattle showed an increasing behavior of age at first calving since 1999 until 2012, that can possibly be explained due to the decreasing behavior of the rainfall throughout the years, that can affect the nutritional value and offer of the grass that can grow in the borders of the crop, such as Guinea and Star grass, and eventually affect the body condition and weight necessary to be ready for the first estrous. An inverse behavior of open days occurred, showing a decreased trend along the last years of research. This fact could have happened due to the intensive use of the enriched rice straw with urea and molasses lately. Regarding to the reproductive trend of the multiparous cattle, there is no an evident pat-tern of it. Factors such as rainfall, temperature, nutrition and management should have affected it. Further research on this topic is needed.

关键词： Rice Crop Residue Reproduction Cebú herd

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地铁车站售检票设施乘客服务时间间隔规律及排队模型研究

地铁车站售检票设施乘客服务时间间隔规律及排队模型研究

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作者：徐婵枝西南交通大学

学位级别：硕士

随着我国大规模规划建设城市轨道交通以应对各大城市交通拥堵问题,车站作为乘客进入轨道交通网络的服务窗口,其建设的经济性,服务的安全性和便利性,是规划设计阶段的关注重点。车站服务设施系统为乘客提供购检票、出入站等服务,其中购... 详细信息

随着我国大规模规划建设城市轨道交通以应对各大城市交通拥堵问题,车站作为乘客进入轨道交通网络的服务窗口,其建设的经济性,服务的安全性和便利性,是规划设计阶段的关注重点。车站服务设施系统为乘客提供购检票、出入站等服务,其中购票、检票环节容易聚集大量乘客排队,减缓乘客进出站的速度,加大在站乘客的安全隐患。可见,售检票设施配置的合理性是车站高效、安全运营的决定性因素。本文以地铁车站的售检票服务设施——进出站自动检票闸机、自动售票窗口和人工售票窗口的乘客服务规律研究为重点,将适宜描述多层次、复杂变动参数变量的通用性及解析性较好的位相型(Phase-type,简称PH)分布引入到描述地铁车站售检票设施的乘客服务时间间隔概率分布中。为了探究售检票设施乘客服务时间间隔服从的概率分布形式,并便于对比分析PH分布的拟合效果,本文选择了8种概率分布,其中包括：位相型分布类中2种特殊形式——PH稠密子集混合爱尔朗分布(Hyper-Erlang Distribution,简称herd)、一种简化的PH分布,以及6种常用的概率分布——均匀分布、正态分布、对数正态分布、威布尔分布、伽马分布。通过对比拟合精度,得到并验证了位相型分布中的herd对乘客服务时间间隔概率分布具有整体最优的拟合效果的结论。由于拟合精度高的herd分布函数相较常用的概率分布函数参数数量要多,为了提高其在地铁车站售检票设施中的实用性,通过探寻各类设施服务时间间隔的herd拟合分布函数的参数相关性,得到了参数的回归方程,成功简化了herd概率分布函数参数的求解方法,最终得到基于售检票设施的乘客服务时间间隔的均值和变异系数平方两个参数,即可获得拟合效果极佳的相应设施的服务时间间隔的herd概率分布函数。在此基础上,为了将本文研究的具有普遍适用性的售检票设施的乘客服务时间间隔的herd模型应用在售检票系统设施数量配置中,建立了PH/PH/C1/C排队模型,并以自动售票机为例,将该排队模型的设施配置结果与依据《地铁设计规范》建议值和实际调查获得的设施静态平均服务能力的配置结果三者进行对比分析,显示了建立排队模型的设施配置方法的优越性。

关键词：地铁车站售检票服务设施乘客服务时间间隔 herd 排队模型

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