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The Influence of Lairage Conditions for Finishing Pigs on Behavior,Biochemical Indicators and Meat Quality
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作者 CHAI Jin PENG Jian +5 位作者 XIONG Qi ZHANG Chang-xin MIAO Wen LI Feng-e ZHENG Rong JIANG Si-wen 《畜牧兽医学报》 CAS CSCD 北大核心 2010年第S1期58-62,共5页
A total of 60 crossbred(Large White×Landrace) pigs of halothane genotype NN(castrated males and females) were allotted to three treatments:3 h lairage with toys,3 h lairage and 0 h lairage in a randomized complet... A total of 60 crossbred(Large White×Landrace) pigs of halothane genotype NN(castrated males and females) were allotted to three treatments:3 h lairage with toys,3 h lairage and 0 h lairage in a randomized complete block design and used to evaluate the influence of lairage conditions on behavior, biochemical indicators and meat quality for finishing pigs at slaughter.Behavior of the pigs was scored subjectively during lairage.Blood samples were taken at exsanguination s to measure blood temperature, plasma Cortisol,ACTH,glucose,lactate,plasma enzymes and hematological indices.Post-mortem meat quality measurements included muscle colour value(MCV),electrical conductivity(EC),pH at 45 min and 24 h from Longissimus thoracis(LM) and Semimembranosus(SM) mucles and drip loss from LM. The results showed that 3 h lairage group with toys demonstrated significantly improved behavior than the group without toys at 3 sampling times.All the pigs showed increasing calmness as the time of lairage progressed.The omission of lairage increased plasma Cortisol,ACTH,glucose and lactate(P【0.05),and decreased plasma lactate dehydrogenase(LDH),and creatine kinase(CK)(P【0.05).No biochemical index was influenced by the presence or absence of toys during lairage(P【0.05).Muscle colour value, electrical conductivity,pH at 45 min and 24 h from LM and SM and drip loss were not affected by any treatment(P【0.05).Pigs provided 3 h lairage,with or without toys,exhibited lower red blood cell(RBC), hemoglobin(HGB),and haematocrit(HCT) when compared to 0 h lairage.3 h lairage with or without toys resulted in higher white blood cell(WBC) and lymphocyte(W-SCC) levels than 0 h lairage.None of the hemocytic indices in pigs given lairage was affected by the presence or absence of toys.We conclude from this pilot study that in local commercial conditions,from the point of view of animal welfare and meat quality,lairage time of 3 h after short travel was beneficial.Pigs resting showed increased relief from stress and a recovery in immune competence.Holding pigs in lairage with toys for a few hours after arrival at the abattoir may be beneficial for the animal’s well-being. 展开更多
关键词 finishing pigs lairage conditions BEHAVIOR biochemical indices meat quality
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A data-driven health indicator extraction method for aircraft air conditioning system health monitoring 被引量:19
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作者 Jianzhong SUN Chaoyi LI +2 位作者 Cui LIU Ziwei GONG Ronghui WANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第2期409-416,共8页
Prognostics and Health Management(PHM) has become a very important tool in modern commercial aircraft. Considering limited built-in sensing devices on the legacy aircraft model,one of the challenges for airborne syste... Prognostics and Health Management(PHM) has become a very important tool in modern commercial aircraft. Considering limited built-in sensing devices on the legacy aircraft model,one of the challenges for airborne system health monitoring is to find an appropriate health indicator that is highly related to the actual degradation state of the system. This paper proposed a novel health indicator extraction method based on the available sensor parameters for the health monitoring of Air Conditioning System(ACS) of a legacy commercial aircraft model. Firstly, a specific Airplane Condition Monitoring System(ACMS) report for ACS health monitoring is defined. Then a non-parametric modeling technique is adopted to calculate the health indicator based on the raw ACMS report data. The proposed method is validated on a single-aisle commercial aircraft widely used for short and medium-haul routes, using more than 6000 ACMS reports collected from a fleet of aircraft during one year. The case study result shows that the proposed health indicator can effectively characterize the degradation state of the ACS, which can provide valuable information for proactive maintenance plan in advance. 展开更多
关键词 Air conditioning SYSTEM Aircraft HEALTH MONITORING AIRPLANE condition MONITORING SYSTEM HEALTH indicator PROGNOSTICS and HEALTH management
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Two Causal-Modeling Approaches to Indicative Conditionals
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作者 ChingHui Su 《逻辑学研究》 2025年第6期43-61,共19页
Recently there have been two causal modelling approaches to indicative conditionals,i.e.extrapolationist(Deng&Lee,2021)and filterist(Liang&Wang,2022),although they all take an interventionist position on subju... Recently there have been two causal modelling approaches to indicative conditionals,i.e.extrapolationist(Deng&Lee,2021)and filterist(Liang&Wang,2022),although they all take an interventionist position on subjunctive conditionals.Motivated by the so-called OK pairs,they try to provide a convincing explanation of the intuition underlying the OK pairs.As far as we know,what they have done is to provide not only an explanation of the OK pairs,but also a way of distinguishing between indicative and subjunctive conditionals.Although we agree with their success in explaining the OK pairs within a causal modelling framework,we argue that their ways of distinguishing between indicative and subjunctive conditionals fail.Instead,we argue that their approaches can be used to distinguish between two readings of conditionals,the epistemic reading and the ontic reading.which can be applied to both indicative and subjunctive conditionals.We conclude by arguing that these two readings are related to two approaches to asking and answering causal questions:the“auses-of-effects"approach and the"effects-of-causes"approach. 展开更多
关键词 subjunctive conditionals extrapolationist causal modelling approaches epistemic reading causal modeling filterist indicative subjunctive con ok pairs
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Evaluation of Selected Quality Degradation Indices for Palestinian Extra Virgin Olive Oil Bottled in Different Packaging Materials upon Storage under Different Lighting Conditions
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作者 Ibrahim Abdullah Afaneh Jehad Abbadi +2 位作者 Ziad Ayyad Wadie Sultan Khalid Kanan 《Journal of Food Science and Engineering》 2013年第5期267-283,共17页
The effect of packaging materials and lighting conditions on quality of extra virgin olive oil (EVOO) was investigated during six months. The results highlighted an influence of light and type of packaging material ... The effect of packaging materials and lighting conditions on quality of extra virgin olive oil (EVOO) was investigated during six months. The results highlighted an influence of light and type of packaging material on EVOO-quality with storage time. At shelf, all packages maintained EVOO at the end of storage in terms of acidity, peroxide value, K232, while K270 exceeded limit of EVOO in glass and PET-stored oil. Loss of phenols was the highest in glass-stored oil and the lowest in high-density polyethylene (HDPE)-stored oil. In terms of sensory evaluation, glass-stored oil lost EVOO grade after three months and its edible compliance after six months, while HDPE-stored oil maintained EVOO grade 90 days and was virgin after six months. In extended lighting, acidity, peroxide value and K232 did not exceed EVOO grade, while K270 exceeded EVOO grade after 30 days in glass and polyethylene terephthalate (PET)-stored oil and after 90 days in HDPE. The loss of phenols was the largest in glass and smallest in HDPE-stored oil. Glass stored-oil lost organoleptic edible compliance before 90 days, while that in PET was virgin at 90 days and that in HDPE maintained EVOO quality 90 days. At the end of experiment, oils in all packages were not edible. In dark, all packages maintained oil in EVOO quality in terms of all indices. The loss of phenols was marginal but was the least in glass and the highest in HDPE. It was concluded that HDPE bottles conserve stored olive oil at shelf or illumination better than PET or glass, while in dark, glass was superior over plastic. 展开更多
关键词 ACIDITY oil oxidation olive oil stability indicators storage conditions
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Folded Radiolarite Unit as a Kinematic Indicator of the Zagros Collision Processes, Southwestern Iran 被引量:3
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作者 Abdolreza Partabian Ahmad Nourbakhsh Khalil Sarkarinejad 《Journal of Earth Science》 SCIE CAS CSCD 2018年第1期210-222,共13页
Radiolarites have an important role in the reconstruction of the paleogeography, bathymetry and their coexistence with ophiolites gives an opportunity to determine the tectonic his- tory of collisional zones. The radi... Radiolarites have an important role in the reconstruction of the paleogeography, bathymetry and their coexistence with ophiolites gives an opportunity to determine the tectonic his- tory of collisional zones. The radiolarite units of the southwestern Neyriz are part of the Zagros ac- cretionary prism and positioned beneath the thick bedded carbonate sediments of Tarbur Forma- tion. The existing various structural elements within this unit give a unique fortunate for investiga- tion on the deformation history and studying of the kinematics of the Zagros collision zone. The nu- merous evidence show that this unit has experienced different deformation conditions during ongo- ing evolution, including ductile, brittle-ductile and brittle deformation conditions. The main strike of E-W for axial planes of folds, eastward trend and plunge of fold axes, boudins' neck axes and Type III of the fold interference patterns are indicators of formation and evolution of folds during tran- spressional deformation. Structural evolution of the study area has been affected by an NE-dipping subduction zone of Neo-Tethyan oceanic lithosphere below the Iranian microcontinents. These structural elements suggest that high mechanical anisotropy and two successive generations of fold- ing simultaneously with thrusting and extrusion of this unit had led to formation and evolution of this highly asymmetrical folded unit on top of the subducted oceanic crust. 展开更多
关键词 Iran ZAGROS suture zone kinematic indicator TRANSPRESSION deformation conditions.
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Hygienic and Sanitary Conditions of Eggs Commercialized in Town Fairs and Markets
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作者 Wanessa Karine da Silva Lima Ludmilla Santana Soares Barros +3 位作者 Ricardo Mendes da Silva Tamiles Barreto de Deus Danuza das Virgens Lima Adriana dos Santos Silva 《Food and Nutrition Sciences》 2018年第7期855-867,共13页
High nutritional content coupled with low cost and ease of purchase justifies the frequent use of chicken eggs. Even with technological innovations in the production, storage, and distribution of eggs, food poisoning ... High nutritional content coupled with low cost and ease of purchase justifies the frequent use of chicken eggs. Even with technological innovations in the production, storage, and distribution of eggs, food poisoning continues to occur. Therefore, in the present study, we 1) evaluated the microbiological profile and the hygienic and sanitary quality of eggs commercialized in town fairs and markets and 2) verified whether there is any correlation between microbiological results and commercialization conditions. Thirty-six samples were collected from six municipalities in the region of Rec?ncavo from Bahia, Brazil. The hygienic and sanitary conditions were analyzed by quantifying the total coliforms, E. coli, mesophilic and psychrotrophic microorganisms, molds, and yeasts, and by the presence of Salmonella sp. The observational analysis showed that 91% and 68% of the samples in town fairs and markets, respectively, did not comply with the requirements of the current Brazilian legislation. There was no significant difference in the microbiological profile among samples from the fairs and markets. Several samples presented relevant significant values, indicating inadequate hygienic conditions and fecal contamination. Salmonella sp. was found in one sample. There was co-relationship between microorganism count and the variables “external dirt”, “external stains”, and “closeness to other products”, with high concentrations of total coliforms and E. coli in the non-conforming samples. Although no limits exist for mold and yeast counts, the presence of fungi makes the product unfit for consumption. Thus, the commercialization of eggs would benefit from more attention and supervision by the relevant authorities. 展开更多
关键词 Contamination EGG SALMONELLA MICROORGANISM indicator HYGIENE condition
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Study of Condition Indices in Goby,Parachaeturichthys Ocellatus(Day,1873)from the Creeks of Mumbai
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作者 Bindu Panicker 《Journal of Fisheries Science》 2021年第1期25-29,共5页
Condition indices study like RNA content,DNA content,RNA:DNA,RNA:protein,RNA:lipid was carried out in goby,Parachaeturichthys ocellatus from the creeks of Mumbai to assess its nutritional status in dif­ferent mon... Condition indices study like RNA content,DNA content,RNA:DNA,RNA:protein,RNA:lipid was carried out in goby,Parachaeturichthys ocellatus from the creeks of Mumbai to assess its nutritional status in dif­ferent months.The study was carried out from June 2010 to September 2011.The range of RNA content in male was 72-185.6μg/100 mg while in female was 82-145.46μg/100 mg.RNA content was high during spawning months.The DNA content showed slight variations with range of 22.56-39.31μg/100 mg in males and 25.20-32.52μg/100 mg in females.The range of ratio of RNA:DNA in males was 2.08-5.13 with an average of 3.74 while in female was 2.92-5.07 with an average of 3.99.The ratio above 2 indicates good condition.The RNA:protein showed an average of 0.0015 in males and 0.0017 in females while the average of RNA:lipid was 0.0176 in males and 0.0127 in females.RNA:protein and RNA:lipid showed the lowest values in post reproductive stages while it increased with the onset of reproductive cycles.The condition indices study showed that P.ocellatus was in good condition throughout the year and the creeks of Mumbai were suitable habitat for feeding and reproduction. 展开更多
关键词 condition indices RNA:DNA RNA:protein RNA:lipid
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Problems and Opportunities for Biometeorological Assessment of Conditions in Cold Season
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作者 Elena S.Andreeva Sergey S.Andreev 《Journal of Atmospheric Science Research》 2023年第4期77-85,共9页
The article is devoted to a discussion of the possibilities of biometeorological assessment of the severity of weather conditions during the cold season.The relevance of the study is ensured not only by the fact that ... The article is devoted to a discussion of the possibilities of biometeorological assessment of the severity of weather conditions during the cold season.The relevance of the study is ensured not only by the fact that residents of a number of states,whose total number is more than 27 million people,live in these extreme climatic conditions,but also by the need to improve biometeorological approaches to assessing the impact of these conditions on the body and health of the population.This study examined biometeorological characteristics that illustrate a measure of cold stress.These include the Siple wind-chill index;Bodman winter severity index;Arnoldi weather hardness coefficient;Mountain wind chill index;weather hardness coefficient according to I.M.Osokin.The results of a comparison of winter severity assessments based on the values of the calculated Siple and Bodman indices made it possible to establish that the Bodman index is more acceptable when assessing mildly severe winters.The most adequate for assessing the“severity”of the cold period against the background of a decrease in air temperature and an increase in wind speed is the Siple index.The need to provide the countries of the world with high-quality hydrometeorological and biometeorological forecast information is justified and relevant.In this regard,these studies are very promising. 展开更多
关键词 Biometeorological indices Severe weather Cold period of the year “rigidity”of weather conditions Cold stress Biometeorological assessment
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符合RDE测试规程的车辆随机行驶工况构建
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作者 胡熙 李菁元 +1 位作者 于晗正男 刘昱 《农机化研究》 北大核心 2026年第3期269-276,共8页
目前,为全面评估车辆排放性能,我国引入了实际行驶排放(RDE)测试标准,测试要求车辆按照市区—市郊—高速不同速度水平的路段顺序连续行驶,分别对各路段行程提出了多方面规定,且使用Pemns设备获得车辆在未预设的随机情景下的道路排放水... 目前,为全面评估车辆排放性能,我国引入了实际行驶排放(RDE)测试标准,测试要求车辆按照市区—市郊—高速不同速度水平的路段顺序连续行驶,分别对各路段行程提出了多方面规定,且使用Pemns设备获得车辆在未预设的随机情景下的道路排放水平。但在实际道路排放水平测量中,Pemns设备受技术限制的影响很大。为此,提出了基于RDE测试规程的随机行驶工况的开发方法和工具,根据速度要求划分市区、市郊和高速短行程。首先,对各短行程库样本进行大量随机组合,并根据路段的具体规定要求进行全面校验后,建立市区、市郊和高速曲线库;其次,通过建立、分析和对比满足不同层次指标条件的备选市郊曲线库,确定最优市郊曲线库;最后,对曲线进行跨路段的随机组合,即时稳定地构建能够反映路线情景且满足RDE规程的随机行驶工况。该方法构建的工况可反映车辆实际行驶特征且满足现有RDE测试在速度、时长、里程、路段比例和动力学特性方面的规程要求,将工况提供给底盘测功机试验操作,评估车辆在未预设的实际道路随机情景下的排放水平,实现将RDE行驶路线从实际道路向试验室的转换。 展开更多
关键词 RDE测试规程 区分化行驶情景 随机工况构建 实际道路排放水平 即时开发 多层次指标条件
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杭州市重要湿地生态状况监测及评估
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作者 王一丹 李伟成 +5 位作者 钱逸凡 张现武 初映雪 吴旭东 姚可侃 翁远玮 《安徽农业科学》 2026年第1期77-82,共6页
[目的]健全重要湿地的生态监测和预警机制。[方法]利用杭州市重要湿地的健康数据,分析其生态状况,全面评估其健康状况。[结果]杭州市7处重要湿地的生态健康状况评估得分和预警等级为千岛湖金竹牌(0.916,无预警)>萧山湘湖(0.756,黄色)... [目的]健全重要湿地的生态监测和预警机制。[方法]利用杭州市重要湿地的健康数据,分析其生态状况,全面评估其健康状况。[结果]杭州市7处重要湿地的生态健康状况评估得分和预警等级为千岛湖金竹牌(0.916,无预警)>萧山湘湖(0.756,黄色)=富阳阳陂湖(0.756,黄色)=钱塘大湾区(0.756,黄色)>西溪湿地(0.750,黄色)>余杭三白潭(0.711,黄色)>淳安千亩田(0.640,黄色);萧山湘湖、富阳阳陂湖和西溪湿地的生态状况具有同质性,受到入侵物种的威胁,植被原真性下降;钱塘大湾区受到周围企业工厂排污的影响;余杭三白潭受到水体富营养化和入侵物种的影响;淳安千亩田受到本土物种种群扩张和旱化的影响。[结论]采用的指标及其赋值系统简洁且契合了杭州重要湿地的生态状况,为湿地生态系统的保护、合理利用和可持续管理提供基础信息和决策依据。 展开更多
关键词 重要湿地 生态状况 健康状况 预警机制 指标赋值
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Competitive location problem of multi-level pickup point considering cooperative coverage 被引量:3
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作者 Han Xun Zhang Jin Zeng Qian 《Journal of Southeast University(English Edition)》 EI CAS 2019年第1期111-117,共7页
To occupy a greater market share in terminal distribution, companies are urged to make full use of cooperative coverage formed with brand effect and information sharing in the layout of pickup points. Based on the div... To occupy a greater market share in terminal distribution, companies are urged to make full use of cooperative coverage formed with brand effect and information sharing in the layout of pickup points. Based on the diversity of pickup points, the piecewise function, signal intensity function and probability function are introduced. Meanwhile, considering the effect of distance satisfaction and cooperation coverage on customer behavior, the location model of the pickup point under competitive environments is established. The genetic algorithm is used to solve the problem, and the effectiveness of the model and algorithm is verified by a case. The results show that the sensitivity of weighted demand coverages to budget decreases gradually. The maximum weighted demand coverage increases at first and then decreases with the increase of the signal threshold, and there is a positive correlation with the change of the actual demand coverage to the senior customers, but it is negatively related to the intermediate and primary customers. When the number of high-level pickup points in a competitive enterprise is small, the advantage of the target enterprise is more significant. Through comparison, the cooperative coverage model is better than the non-cooperative coverage model, in terms of the weighted demand coverage, the construction cost and the attention paid to the important customers. 展开更多
关键词 pickup point cooperative coverage multi-level facility layout competitive conditions genetic algorithm
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Few-shot working condition recognition of a sucker-rod pumping system based on a 4-dimensional time-frequency signature and meta-learning convolutional shrinkage neural network 被引量:2
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作者 Yun-Peng He Chuan-Zhi Zang +4 位作者 Peng Zeng Ming-Xin Wang Qing-Wei Dong Guang-Xi Wan Xiao-Ting Dong 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1142-1154,共13页
The accurate and intelligent identification of the working conditions of a sucker-rod pumping system is necessary. As onshore oil extraction gradually enters its mid-to late-stage, the cost required to train a deep le... The accurate and intelligent identification of the working conditions of a sucker-rod pumping system is necessary. As onshore oil extraction gradually enters its mid-to late-stage, the cost required to train a deep learning working condition recognition model for pumping wells by obtaining enough new working condition samples is expensive. For the few-shot problem and large calculation issues of new working conditions of oil wells, a working condition recognition method for pumping unit wells based on a 4-dimensional time-frequency signature (4D-TFS) and meta-learning convolutional shrinkage neural network (ML-CSNN) is proposed. First, the measured pumping unit well workup data are converted into 4D-TFS data, and the initial feature extraction task is performed while compressing the data. Subsequently, a convolutional shrinkage neural network (CSNN) with a specific structure that can ablate low-frequency features is designed to extract working conditions features. Finally, a meta-learning fine-tuning framework for learning the network parameters that are susceptible to task changes is merged into the CSNN to solve the few-shot issue. The results of the experiments demonstrate that the trained ML-CSNN has good recognition accuracy and generalization ability for few-shot working condition recognition. More specifically, in the case of lower computational complexity, only few-shot samples are needed to fine-tune the network parameters, and the model can be quickly adapted to new classes of well conditions. 展开更多
关键词 Few-shot learning indicator diagram META-LEARNING Soft thresholding Sucker-rod pumping system Time–frequency signature Working condition recognition
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Performance evaluation of near real-time condition monitoring in haul trucks 被引量:1
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作者 Hemanth Reddy Alla Robert Hall Derek B.Apel 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2020年第6期909-915,共7页
Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive ... Strategic maintenance plays a key role in ensuring high availability and utilization of the haul trucks,and as equipment began to grow more complex towards the end of the 20th century,there was a need for a proactive maintenance strategy,which led to the development of condition-based maintenance.Realtime condition monitoring(RTCM)is the ability to perform condition monitoring in real-time and has the ability to alert maintenance and operations of abnormal conditions.These alarms can be used as an indication leading to a problem,and if a suitable corrective action is initiated in time,it could result in significant savings of equipment downtime and repair costs.This study aims to compare some maintenance performance indicators prior to and after implementation of RTCM strategy at a mine site using some tests of statistical significance.The study also indicated the presence of seasonality in the data,and thus the data was deseasonalized and detrended prior to being subjected to the statistical tests.Finally,the results indicated that RTCM strategy has proven to be successful in improving the availability for some of the failure categories chosen in this study. 展开更多
关键词 Haul trucks Real-time condition monitoring Performance indicators
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Key Points of Attention in Multi-level Capital Markets and Listing Audit —— Analyze the Key Points of the Listing Audit of Enterprises Based on Actual Cases
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作者 HUANG Chengyi 《外文科技期刊数据库(文摘版)经济管理》 2021年第8期059-063,共7页
In recent years, the CPC Central Committee and the State Council have attached great importance to the development of capital markets. The future development trend is to establish and continuously improve a multi-leve... In recent years, the CPC Central Committee and the State Council have attached great importance to the development of capital markets. The future development trend is to establish and continuously improve a multi-level capital market, expand and increase the proportion of direct financing, and allow more financial resources to be allocated through the capital market. The development of multi-level capital market is beneficial to China's economic transformation and upgrading and structural adjustment. It is beneficial to cultivate and strengthen the real economy. It is conducive to improving the allocation efficiency of financial resources;It is conducive to promoting the development of strategic emerging industries and sustainable economic growth. Based on the introduction of the multi-level capital market system, the listing conditions of enterprises and the analysis of the significance of listing to the development of enterprises, this paper analyzes and discusses the key points of financial and legal audit of enterprises' listing combined with actual cases. 展开更多
关键词 multi-level capital market listing conditions MEANING key points of audit
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基于多分支融合嵌入式注意力特征提取的油井工况诊断
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作者 王通 李远超 +1 位作者 高宪文 王寒静 《控制与决策》 北大核心 2025年第5期1742-1750,共9页
针对油井示功图特征提取效果不佳导致工况诊断准确率不高的问题,提出一种基于多分支融合嵌入式注意力特征提取的油井工况诊断方法.首先,为使提取的示功图隐含特征信息更加全面,在卷积自编码器的基础上,设计多分支、多尺度的编码器结构提... 针对油井示功图特征提取效果不佳导致工况诊断准确率不高的问题,提出一种基于多分支融合嵌入式注意力特征提取的油井工况诊断方法.首先,为使提取的示功图隐含特征信息更加全面,在卷积自编码器的基础上,设计多分支、多尺度的编码器结构提取,并融合示功图位移-载荷数据的特征信息;其次,为强化多分支融合后的局部特征,设计一种嵌入式通道注意力机制,在全局平均池化基础上,添加全局最大池化,使其能够同时关注示功图全局和局部特征;同时,为进一步增强示功图关键信息的隐含特征提取能力,在通道挤压后,激励之前嵌入通道注意力机制模块对挤压后的通道预先进行一次权重调整,激励后进行权重的二次调整;最后,将提取的特征放入长短期记忆网络模型中进行油井工况诊断.结果表明,基于多分支融合嵌入式注意力特征提取的油井工况诊断方法在一定程度上改善了示功图有效特征提取能力,提高了油井工况诊断率,能够满足油田现场的实际需求. 展开更多
关键词 示功图 特征提取 工况诊断 卷积自编码器 注意力机制 长短期记忆网络
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柴达木盆地西缘砂岩型铀矿成矿条件及找矿标志 被引量:2
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作者 张希梁 蔡煜琦 +1 位作者 赵兴齐 贺锋 《铀矿地质》 2025年第1期29-43,共15页
铀矿是重要的战略性矿产资源,柴达木盆地是我国主要的砂岩型铀矿分布地区之一,盆地西缘是近年来“新区、新层位、新类型”铀矿三新找矿突破的重要地区,砂岩型铀成矿潜力大。为了进一步明确该地区的新生代砂岩型铀成矿规律,为下一步的找... 铀矿是重要的战略性矿产资源,柴达木盆地是我国主要的砂岩型铀矿分布地区之一,盆地西缘是近年来“新区、新层位、新类型”铀矿三新找矿突破的重要地区,砂岩型铀成矿潜力大。为了进一步明确该地区的新生代砂岩型铀成矿规律,为下一步的找矿预测提供依据,文章在系统地收集、整理区域多源地学信息的基础上,从铀源、构造、沉积建造、水文地质、后生蚀变等方面,分析了柴达木盆地西缘铀成矿条件,初步厘定了铀成矿控矿要素,明确了找矿标志。结果表明:该地区具有祁漫塔格山等蚀源区和本身富铀的沉积盖层双重铀源;铀矿化主要位于上油砂山组(N_(2)^(2)y)、狮子沟组(N_(2)^(3)s)、七个泉组(Q_(1-2)q)等新近系和第四系层位;背斜核部及两翼缓倾斜坡带是成矿发育的有利构造部位;三角洲平原及前缘相发育区,河道砂体发育,泥-砂-泥结构稳定,有利于砂岩型铀成矿;成矿过程受渗入含铀流体的层间氧化和油气渗出还原的复合作用控制,是叠合复成因砂岩型铀矿有利找矿地区。 展开更多
关键词 砂岩型铀矿 柴达木盆地 成矿条件 找矿标志
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妊娠后期不同能量和蛋白质水平饲粮对多羔母羊初乳成分和羔羊体况及血清生化、抗氧化和免疫指标的影响
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作者 陈乐祥 达拉胡 +7 位作者 萨茹丽 哈斯额尔敦 白晨 木其尔 曹琪娜 郑彦楷 刘学文 敖长金 《动物营养学报》 北大核心 2025年第11期7732-7743,共12页
本试验旨在研究妊娠后期饲喂不同能量和蛋白质水平饲粮对多羔母羊初乳成分和羔羊体况及血清生化、抗氧化和免疫指标的影响。试验以东寒湖(东弗里生羊×小尾寒羊×湖羊)杂交羊为试验动物,通过B超检测选择怀2~3羔的妊娠期[妊娠(75... 本试验旨在研究妊娠后期饲喂不同能量和蛋白质水平饲粮对多羔母羊初乳成分和羔羊体况及血清生化、抗氧化和免疫指标的影响。试验以东寒湖(东弗里生羊×小尾寒羊×湖羊)杂交羊为试验动物,通过B超检测选择怀2~3羔的妊娠期[妊娠(75±5)d]体况健康、体重为(72.49±3.69)kg的母羊90只,随机分为3组,每组6个重复,每个重复5只。各组母羊分别饲喂低能量低蛋白质水平饲粮[LELP组,代谢能(ME)为8.31 MJ/kg、粗蛋白质(CP)为11.25%]、中能量中蛋白质水平饲粮(MEMP组,ME为8.65 MJ/kg、CP为12.15%)和高能量高蛋白质水平饲粮(HEHP组,ME为9.00 MJ/kg、CP为13.12%)。预试期15 d,正试期85 d(母羊妊娠90 d至分娩后25 d)。结果表明:1)LELP组初乳非脂乳固体、乳蛋白、乳脂和乳糖含量显著或极显著高于HEHP组(P<0.01或P<0.05);2)各组间羔羊初生体重、断奶体重、平均日增重和体尺指标无显著差异(P>0.05);3)各组间羔羊血清生化指标无显著差异(P>0.05);4)LELP组羔羊血清总抗氧化能力和过氧化氢酶活性显著或极显著高于MEMP组(P<0.01或P<0.05);5)各组间羔羊血清免疫球蛋白A、免疫球蛋白G和免疫球蛋白M含量无显著差异(P>0.05)。综上所述,母羊妊娠后期饲喂不同能量和蛋白质水平饲粮对羔羊体况以及血清生化和免疫指标无显著影响,降低饲粮能量和蛋白质水平有利于提高初乳成分含量和羔羊抗氧化能力。 展开更多
关键词 妊娠后期 能量 蛋白质 初乳 羔羊 体况 血清指标
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基于LM-BPNN的高寒地区地下水微生物-毒理指标预测模型
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作者 贾卓鹏 毕俊擘 +3 位作者 原勇 权昕 王帅伟 孙伟超 《地质科技通报》 北大核心 2025年第2期368-377,共10页
为建立高寒地区地下水微生物-毒理指标(细菌菌落总数(total bacteria count,简称TBC)、总大肠杆菌菌落总数(total coliforms count,简称TCC))预测模型,以我国西南高原地区某一水源地地下水微生物-毒理指标(TBC、TCC)为研究对象,通过正... 为建立高寒地区地下水微生物-毒理指标(细菌菌落总数(total bacteria count,简称TBC)、总大肠杆菌菌落总数(total coliforms count,简称TCC))预测模型,以我国西南高原地区某一水源地地下水微生物-毒理指标(TBC、TCC)为研究对象,通过正交试验设计,改变温度、pH值、孔隙率等外部环境条件,开展室内批试验,获取了不同孔隙率、取样深度,流出溶液的温度、pH值、化学需氧量(chemical oxygen demand,简称COD)、氧化还原电位(oxidation-reduction potential,简称ORP)等地下水水质指标及地下水中TBC和TCC值,然后分别以TBC、TCC为目标,以取样深度、溶液温度、pH值、土壤孔隙率、ORP、COD为影响因素,基于Levenberg-Marquardt(LM)优化的神经网络(BPNN)算法,建立了高寒地区地下水微生物-毒理指标的预测模型。结果表明,TBC、TCC模型的预测结果与试验结果的变化趋势一致,且最大相对误差均小于15%(TBC、TCC模型的最大相对误差分别为11.52%,14.55%),符合工程要求。该方法可用于高寒地区地下水微生物-毒理指标的预测,可为高原地区地下水资源可持续利用和污染的有效防治提供科学依据,并为地下水中TBC、TCC的测定提供新的思路。 展开更多
关键词 微生物-毒理指标 TCC TBC 环境条件 地下水水质指标 LM-BPNN 预测模型 高寒地区
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德国次级区域同等生活条件评估的方法与经验启示
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作者 薛诗睿 雷振东 高雅 《国际城市规划》 北大核心 2025年第5期81-88,共8页
“同等生活条件”是德国用于彰显社会公平、凸显福利国家性质的长期目标,指在任一地区内人们获得生产、生活等服务的机会一致,包含地区的差异性与多样性。起初这一目标是为解决战后工业化冲击带来的城乡差距问题,后转为解决由东、西分... “同等生活条件”是德国用于彰显社会公平、凸显福利国家性质的长期目标,指在任一地区内人们获得生产、生活等服务的机会一致,包含地区的差异性与多样性。起初这一目标是为解决战后工业化冲击带来的城乡差距问题,后转为解决由东、西分裂带来的基础设施差异问题,但由于德国联邦主义的权限错综复杂,该目标的系统性与正规性一直存疑。2018年联邦提出建立次级区域生活条件的评估监测体系,旨在通过“指标选取—因子分析—地区分类—细化指标—特征识别”五个步骤计算各类型区与全国平均水平的比对情况,判定得出该类型区生活条件水平的结构性劣势与风险,为后续政策扶持与资金供给提供依据。该体系有两点优势,一是通过科学系统的分析数据得出描述生活条件的关键指标,能客观描述地区与全国平均水平的差异,无等级之分;二是在类型化地区生活条件后筛选“刚性(客观配置)与弹性(主观评价)”双向指标,便于政府/利益相关者更为精准地明晰生活条件的差异。这对于我国国土空间规划前期评估中“公共服务与基础设施”部分的现状评价具有科学化的指导意义,或将为后续规划开展、政策落位和对口帮扶提供更为精准的参考。 展开更多
关键词 同等生活条件 生活条件评估 基本公共服务均等化 结构性指标 现状评估 社会公正
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基于深度学习的水利工控网络流量异常检测方法 被引量:2
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作者 马剑波 左翔 +2 位作者 丛小飞 叶瑞禄 刘威风 《水利水电技术(中英文)》 北大核心 2025年第4期167-178,共12页
【目的】针对水利工控网络流量数据集不平衡、特征维数多和检测效率低等问题,提出一种结合改进条件生成对抗网络(ICGAN)、深度残差收缩网络(DRSN)、长短期记忆网络(LSTM)的流量异常检测方法。【方法】利用ICGAN构建了网络流量平衡数据集... 【目的】针对水利工控网络流量数据集不平衡、特征维数多和检测效率低等问题,提出一种结合改进条件生成对抗网络(ICGAN)、深度残差收缩网络(DRSN)、长短期记忆网络(LSTM)的流量异常检测方法。【方法】利用ICGAN构建了网络流量平衡数据集,利用DRSN-LSTM混合深度学习模型对网络异常流量数据进行检测,其中DRSN负责提取数据的空间特征,其残差连接可以解决网络退化与过拟合问题,压缩和激励网络可自动为每个特征图分配权重系数以提高检测效果,LSTM负责提取数据的时间特征。【结果】以秦淮河武定门闸站为应用场景对该方法进行测试,结果表明采用ICGAN优化后的数据集训练的各类检测模型,其流量分类精度高于原始数据集。DRSN-LSTM的网络流量异常检测的总体准确率达到了98.76%,其中正常数据分类的P、R和F1值,分别达到了99.22%、99.69%和99.46%,在评价指标上优于比较模型。【结论】融合ICGAN、DRSN和LSTM算法优势的水利工控网络流量异常检测方法,能够有效改善原始数据集中的类别不平衡性问题,提高对异常工控网络流量的检测能力,保障水利工程安全稳定运行。 展开更多
关键词 水利工控 网络流量异常检测 深度学习 条件生成对抗网络 深度残差收缩网络 长短期记忆网络 评价指标
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