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Estimating purple-soil moisture content using Vis-NIR spectroscopy

Journal of Mountain Science 2020年第9期17卷 2214-2223页

作者： GOU Yu WEI Jie LI Jin-lin HAN Chen tu Qing-yan LIU Chun-hong School of Geography and Tourism Science Chongqing Normal UniversityChongqing 401331China Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area Chongqing 401331China

Soil moisture is essential for plant growth in terrestrial *** study investigated the visible-near infrared(Vis-NIR)spectra of three subgroups of purple soils(calcareous,neutral,and acidic)from western Chongqing,China,containing different water *** relationship between soil moisture and spectral reflectivity(R)was analyzed using four spectral transformations,and estimation models were established for estimating the soil moisture content(SMC)of purple soil based on stepwise multiple linear regression(SMLR)and partial least squares regression(PLSR).We found that soil spectra were similar for different moisture contents,with reflectivity decreasing with increasing moisture content and following the order neutral>calcareous>acidic purple soil(at constant moisture content).Three of the four spectral transformations can highlight spectral sensitivity to SMC and significantly improve the correlation between the reflectance spectra and *** and PLSRmethods provide similar prediction *** PLSR-based model using a first-order reflectivity differential(R?)is more effective for estimating the SMC,and gave coefficient of determination(v2),root mean square errors of validation(RMSEV),and ratio of performance to inter-quartile distance(RPIQ)values of 0.946,1.347,and 6.328,respectively,for the calcareous purple soil,and 0.944,1.818,and 6.569,respectively,for the acidic purple *** neutral purple soil,the best prediction was obtained using the SMLR method with R?transformation,yieldingv2,RMSEV and RPIQ values of 0.973,0.888 and 8.791,*** general,PLSR is more suitable than SMLR for estimating the SMC of purple soil.

关键词： Purple soil Soil moisture Vis-NIR spectroscopy Stepwise multiple linear regression Partial least squares regression

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Effects of different feeding methods and space allowance on the growth performance, individual and social behaviors of Holstein calves

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Journal of Integrative Agriculture 2017年第6期16卷 1375-1382页

作者： DONG Li-feng XU Xian-cha ZHANG Nai-feng tu yan DIAO Qi-yu Feed Research Institute Chinese Academy of Agricultural Sciences/Key Laboratory of Feed Biotechnology Ministry of Agriculture Beijing 100081 P.R. China

The importance of nutrient provisions and weaning methods for calves has been well established over the past few years,while as increasing interest has focused on contribution of animal behavior and their overall performance in production *** present study investigated the effects of feeding methods and space allowance on growth performance,individual and social behaviors in Holstein ***-four Chinese Holstein male and female calves were allocated to either an individual or group of 6 and fed either with a bucket or a *** replacer,calf starter,and Chinese wildrye were offered during the experiment.A fecal index used in the present study was defined as the total fecal scores/total number of calves in each *** results showed that there was no significant difference among the 4 treatments in terms of feed intake,body weight,average daily gain,and fecal *** the feeding behaviors,the ingesting milk time and ingesting milk rate were significantly affected by space allowance,while the feeding methods showed a significant influence on the bunting behavior of the *** was no significant difference among the 4 treatments in terms of licking fixtures,self-grooming,and lying down behaviors,irrespective of the feeding method or space ***,sucking an empty bucket or the teat was significantly affected by the feeding *** selected group behaviors were examined in the present study,and similar values for sniffing the other calves,social grooming,and cross-sucking behaviors were ***,the present study demonstrated that different feeding methods and space allowances had a significant effect on the feeding behavior of calves,while the feed intake,growth performance,health condition,individual and group social behaviors were not significantly ***,under intensified production systems,Holstein calves raised in a group may obtain a similar production performance,thus reducing management in

关键词： dairy calves feeding approach space allowance growth performance animal behavior

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Effect of supplementation of allicin on methanogenesis and ruminal microbial flora in Dorper crossbred ewes

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Journal of Animal Science and Biotechnology 2016年第2期7卷 194-200页

作者： Tao Ma Dandan Chen yan tu Naifeng Zhang Bingwen Si Kaidong Deng Qiyu Diao Feed Research Institute Chinese Academy of Agricultural Sciences Key Laboratory of Feed Biotechnology of the Ministry of Agriculture College of Animal Science Jinling Institute of Technology

Background： Garlic extracts have been reported to be effective in reducing methanogenesis. Related mechanisms are not well illustrated, however, and most studies have been conducted in vitro. This study investigates the effects of supplementary allicin（AL） in sheep diet on in vivo digestibility, rumen fermentation, and shifts of microbial ***： Two experiments were conducted using Dorper × thin-tailed Han crossbred ewes. In experiment 1,eighteen ewes（60.0 ± 1.73 kg BW） were randomly assigned for 29 days to either of two dietary treatments： a basal diet or the basal diet supplemented with 2.0 g AL/head？day to investigate supplementary AL on nutrient digestibility and methane emissions. In experiment 2, six ewes（65.2 ± 2.0 kg BW） with ruminal canulas were assigned to the same two dietary treatments as in experiment 1 for 42 days to investigate supplementary AL on ruminal fermentation and microbial flora. The methane emissions were determined using an open-circuit respirometry system and microbial assessment was done by q PCR of 16 S r RNA ***： Supplementary AL increased the apparent digestibility of organic matter（P 〈 0.001）, nitrogen（P = 0.006）,neutral detergent fiber（P 〈 0.001）, and acid detergent fiber（P = 0.002）. Fecal nitrogen output was reduced（P = 0.001）but urinary nitrogen output was unaffected（P = 0.691）, while nitrogen retention（P = 0.077） and nitrogen retention/nitrogen intake（P = 0.077） tended to increase. Supplementary AL decreased methane emissions scaled to metabolic bodyweight by 5.95 %（P = 0.007） and to digestible organic matter intake by 8.36 %（P = 0.009）. Ruminal p H was unaffected（P = 0.601） while ammonia decreased（P = 0.024） and total volatile fatty acids increased（P = 0.024） in response to supplementary AL. Supplementary AL decreased the population of methanogens（P = 0.001） and tended to decrease that of protozoans（P = 0.097）, but increased the populations of F. succinogenes（P 〈 0.001）, R. flavefaciens（P = 0.001）, and B. fibris

关键词： Allicin Digestibility Ewe Methane Microbial flora

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Net protein and metabolizable protein requirements for maintenance and growth of early-weaned Dorper crossbred male lambs

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Journal of Animal Science and Biotechnology 2017年第3期8卷 701-706页

作者： Tao Ma Kaidong Deng yan tu Naifeng Zhang Bingwen Si Guishan Xu Qiyu Diao Feed Research Institute/Key laboratory of Feed Biotechnology of the Ministry of Agriculture Chinese Academy of Agricultural Sciences College of Animal Science Jinling Institute of Technology College of Animal Science Tarim University

Background： Dorper is an important breed for meat purpose and widely used in the livestock industry of the ***, the protein requirement of Dorper crossbred has not been investigated. The current paper reports the net protein（NP） and metabolizable protein（MP） requirements of Dorper crossbred ram lambs from 20 to 35 kg ***： Thirty-five Dorper × thin-tailed Han crossbred lambs weaned at approximately 50 d of age（20.3 ± 2.15 kg of BW） were used. Seven lambs of 25 kg BW were slaughtered as the baseline animals at the start of the trial. An intermediate group of seven randomly selected lambs fed ad libitum was slaughtered at 28.6 kg BW. The remaining 21 lambs were randomly divided into three levels of dry matter intake： ad libitum or 70% or 40% of ad libitum intake. Those lambs were slaughtered when the lambs fed ad libitum reached 35 kg BW. Total body N and N retention were ***： The daily NP and MP requirements for maintenance were 1.89 and 4.52 g/kg metabolic shrunk BW（SBW0.75）.The partial efficiency of MP utilization for maintenance was 0.42. The NP requirement for growth ranged from 12.1 to 43.5 g/d, for the lambs gaining 100 to 350 g/d, and the partial efficiency of MP utilization for growth was ***： The NP and MP requirements for the maintenance and growth of Dorper crossbred male lambs were lower than the recommendations of American and British nutritional systems.

关键词： Growth Lamb Maintenance Metabolizable protein Net protein

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Contrast induced nephropathy after percutaneous coronary intervention： risk factors and preventive strategy

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Journal of Geriatric Cardiology 2009年第4期6卷 218-221页

作者： yan tu Hua Zheng Yue-Gang Wang Yong Li Department of Cardiology Nanfang Hospital Southern Medical University Guangzhou 510515 China

Objective To analyze the risk factors and clinical outcome of contrast induced nephropathy （CIN） in patients with coronary artery disease （CAD） after percutaneous coronary intervention （PCI） and discuss its prevention. Methods Fifty-four patients with C1N among 729 patients who received PCI were retrospectively studied and the related risk factors, cardiovascular events and preventive strategy were analyzed. Results C1N was strongly associated with pre-procedure chronic renal failure, diabetes mellitus and large-dose contrast. The incidence of cardiac mortality and major adverse cardiac events 1 year after PCI in CIN group was higher than that in group without CIN. Conclusion Chronic renal failure, diabetes mellitus and dosage of contrast agent were three independent risk factors of CIN. CIN could affect the patients＇ prognosis. A well overall perioperative management of CAD patients following PCI, especially hydration therapy, is the most important strategy for prevention of CIN.

关键词： coronary artery disease percutaneous coronary intervention contrast induced nephropathy

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Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： yan Liang Song Chen Xin Dong tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

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Climatic and geographic factors affect ecosystem multifunctionality through biodiversity in the Tibetan alpine grasslands

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Journal of Mountain Science 2017年第8期14卷 1604-1614页

作者： PAN Ying WU Jun-xi LUO Li-ming tu yan-li YU Cheng-qun ZHANG Xian-zhou MIAO yan-jun ZHAO yan yanG Jun-ling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Agricultural Research Institute Tibet Academy of Agricultural and Animal Sciences Tibet Plateau Institute of Biology Agricultural and Animal Husbandry College of Tibet University

Ecosystem multifunctionality(EMF), the simultaneous provision of multiple ecosystem functions, is often affected by biodiversity and environmental factors. We know little about how the interactions between biodiversity and environmental factors affect EMF. In this case study, a structural equation model was used to clarify climatic and geographic pathways that affect EMF by varying biodiversity in the Tibetan alpine grasslands. In addition to services related to carbon, nitrogen, and water cycling, forage supply, which is related to plantproductivity and palatability, was included in the EMF index. The results showed that 72% of the variation in EMF could be explained by biodiversity and other environmental factors. The ratio of palatable richness to all species richness explained 8.3% of the EMF variation. We found that air temperature, elevation, and latitude all affected EMF, but in different ways. Air temperature and elevation impacted the aboveground parts of the ecosystem, which included plant height, aboveground biomass, richness of palatable species, and ratio of palatable richness to all species richness. Latitude affected EMF by varying both aboveground and belowground parts of the ecosystem, which included palatable speciesrichness and belowground biomass. Our results indicated that there are still uncertainties in the biodiversity–EMF relationships related to the variable components of EMF, and climatic and geographic factors. Clarification of pathways that affect EMF using structural equation modeling techniques could elucidate the mechanisms by which environmental changes affect EMF.

关键词： Alpine grassland Biodiversity Structural equation model Tibetan Plateau

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注塑条件对抗冲聚丙烯力学性能影响研究

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广州化工 2024年第2期52卷 128-130页

作者：唐婧李丽刘小燕程鹏飞涂晓燕李广全中国石油天然气股份有限公司兰州化工研究中心甘肃兰州730060

不同的注塑工艺条件会影响聚丙烯微观结构及力学性能,主要研究了注射速率(v)、注射压力(P_(1))、保压压力(P_(2))、保压时间(t)和熔体温度(T)五个参数对高流动抗冲共聚聚丙烯SP531冲击强度和弯曲模量的影响,并分析了注塑条件与力学性能... 详细信息

不同的注塑工艺条件会影响聚丙烯微观结构及力学性能,主要研究了注射速率(v)、注射压力(P_(1))、保压压力(P_(2))、保压时间(t)和熔体温度(T)五个参数对高流动抗冲共聚聚丙烯SP531冲击强度和弯曲模量的影响,并分析了注塑条件与力学性能的关系,结果表明:对于高流动SP531,最佳的注塑条件为注射速率30%,注射压力2 MPa,保压压力4 MPa,保压时间40 s,熔体温度200℃。

关键词：注塑工艺抗冲聚丙烯控制变量法极差分析法力学性能

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Rumen fermentation and bacterial communities in weaned Chahaer lambs on diets with different protein levels

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Journal of Integrative Agriculture 2016年第7期15卷 1564-1574页

作者： yanG Chun-tao SI Bing-wen DIAO Qi-yu JIN Hai ZENG Shu-qin tu yan Feed Research Institute Chinese Academy of Agricultural Sciences/Key Laboratory of Feed BiotechnologyMinistry of AgricultureBeijing 100081P.R.China Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences Huhhot 010000P.R.China

We evaluatedthe effects of diets with different crude protein （CP） levels on growth performance, rumen fermentation and bacterial communities in weaned Chahaer lambs. 128 weaned Chahaer lambs （（20.56±1.43） kg body weight; ram：ewe 1：1） aged （61±1.85） d were randomly alotted to one of four diets with CP content of 11.17% （T1）, 12.06% （T2）, 13.40% （T3） or 14.36% （T4）.Ruminal fermentation parameters were measured and bacterial communities were analysed using PCR-dena-turing gradient gel electrophoresis （PCR-DGGE） and quantitative PCR. The average daily gain and feed utilization efifciency in T3 were higher than those in the other groups （P〈0.05）, although the dry matter intake and metabolizable energy intake were similar. Total volatile fatty acid concentration in the ruminal lfuid of T3 was lower than that of T1 （P=0.011）, T2 （P=0.008） or T4 （P=0.309）. The ammonia nitrogen concentration and acetate/propionate ratio of ruminal lfuid were signiifcantly higher in lambs fed the higher CP diets, whereas the molar concentrations of propionate and butyrate of ruminal lfuid were lower. The rumen bacterial community was similar in T2 and T3 which shown more stable and diverse rumen microbes ecosystem compared with the other groups. The DGGE proifles and phylogenetic tree indicated thatBacteroides uniformis,Clostrid-iumalkalicellulosi,Alkalibaculum *** common bacterium of Chahaer lamb rumen. B. uniformis,***,Saccharofermentanssp. andGracilibacter thermotolerans,which belong to the Bacteroidetes and Firmicutesphyla,were the dominant species in the rumen of lambs fed 13.40% ***,Ruminococcus albus, Ruminococcus lfavefaciensand Butyrivibrio ifbrisolvenswerenot differentin lambs fed different CP diets. Therefore, it could be concluded thatB. uniformis,***,A. *** common bacteria of Chahaer lamb rumen. Furthermore, the dietary CP of 13.04% could improve performance and change rumen fermentati

关键词： dietary crude protein rumen fermentation bacterial diversity weaned lamb PCR-DGGE

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Application　of　Artificial　Neural　Network　in　Designing　Deflection　Coil

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Journal of Systems Engineering and Electronics 1998年第3期9卷 44-51页

作者： tu yan(Electronic Engineering Department of Southeast University, Nanjing 210018, P. R. China) Electronic Engineering Department of Southeast University Nanjing 210018 P. R. China

In the design of deflection coil, we have to determine those values of descriptive parameters of the deflection coil that will give us a required performance. In this paper, an artificial neural network is used in the design of deflection coil. It is shown that the artificial neural network is indeed possible to develop well-trained networks for designing a particular deflection coil.

关键词： Artificial neural network Deflection coil Multipole field

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