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通过TISAX模式加强汽车产业链信息安全的途径分析
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作者 刘海 韦斌生 《工业信息安全》 2024年第2期71-80,共10页
汽车产业链上的各级厂商通常需要与世界各地的客户或下级供应商频繁交换与产品设计、技术研究项目或商业计划有关的商业敏感和机密信息,因而沿产业链传递的信息安全对于各级厂商非常重要。本文通过考察现有的汽车产品开发模式和方法,分... 汽车产业链上的各级厂商通常需要与世界各地的客户或下级供应商频繁交换与产品设计、技术研究项目或商业计划有关的商业敏感和机密信息,因而沿产业链传递的信息安全对于各级厂商非常重要。本文通过考察现有的汽车产品开发模式和方法,分析了汽车产业链内生产厂商信息安全的特征和保障内容,总结了在汽车产业链上保障信息安全的特殊需求。依据可信信息安全评估交换(TISAX)机制及其所依赖的信息安全评估准则(ISA),本文描述了一种加强汽车产业链全链条信息安全的实现途径,说明了如何利用TISAX模式为汽车产业链上的各级厂商提供一种通用的信息安全要求的传递机制。 展开更多
关键词 可信信息安全 评估交换 汽车产业链 管理体系
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Evaluation of Spatial Variability of Soil Properties in a Long-Term Experimental Tobacco Station in Southwest China 被引量:1
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作者 Jiang Houlong Wang Hongfeng +6 位作者 Li Najia Xu Anding Yang Chao Chen Yiyin Li Yong Geng Lina Liu Guo-Shun 《Journal of Agricultural Science and Technology(A)》 2014年第9期723-735,共13页
Analysis of the spatial variability of soil properties is important to arrange the experimental treatments in the experimental station. This paper aims to study the spatial structure of soil variables and their distri... Analysis of the spatial variability of soil properties is important to arrange the experimental treatments in the experimental station. This paper aims to study the spatial structure of soil variables and their distribution in the Pengshui tobacco experiment station in Chongqing, China. Soil samples were taken from 289 soil points on 20 m grid in March 2012. Twenty-two soil chemical and physical properties were analyzed by classical statistical and geo-statistical methods. Soil pH, cation exchange capacity (CEC), total phosphorus (TP), available phosphorus (AP), zinc (Zn), magnesium (Mg) and sulphur (S) have the strong spatial dependence, with nugget/sill ratios of less than 25%. The others have the moderate dependence with nugget/sill ratios of 26.17% to 71.04%. Ranges of the spatial correlation varied from 51.30 m for chlorine (C1) to 594.90 m for TP. The clearly patchy maps of the nutrients showed the spatial distributions of the soil variables, which can be used for better management of experimental treatments, achieving reliable exoerimental results in the tobacco exnerimental station.Highlight: Scientific experimentation assumes the existence of random variability for soil attributes. This research was to evaluate the spatial variability of soil chemical and physical attributes and to interpolate the spatial distribution of soil properties in the tobacco experimental station in Chongqing. The result of this work can be used for the agricultural management of tobacco cultivation. 展开更多
关键词 Geo-statistical analysis soil property spatial variability tobacco experimental station.
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Assessment of Cation Exchange Membrane Method and Estimation of Potassium Critical Values 被引量:1
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作者 SHENJIANBO J.J.SCHOENAU 《Pedosphere》 SCIE CAS CSCD 1996年第2期129-138,共10页
Soil and tissue analyses are usually used in identifying potassium(K) deficiencies and predicting K fertilizer requirements of crops.The critical levels of both soil and fresh leaf tissue at seventh leaf stage were de... Soil and tissue analyses are usually used in identifying potassium(K) deficiencies and predicting K fertilizer requirements of crops.The critical levels of both soil and fresh leaf tissue at seventh leaf stage were developed and assessed for canola,chickpea and sunflower grown on two Saskatchewan,soils,with six rates of K fertilizer supply, in a growth chamber experiment.The available potassium in soils was determined by two methods:1)resin strip extraction, and 2) NH4OAC extraction. The potassium in fresh leaves was determined at seventh leaf stage by a simple procedure using a common garlic press and injector to extract the plant sap and testing the sap with a handheld ion selection electrode meter. The results shoWed significant relationships between the resin strip extractable K and NH4OAC extractable K, and between the plant uptake of total K and the supply of available K in the soils determined by the two methods. Good relationships were also found between the potassium in fresh leaves and the plant uptake of total K for canola, chickpea and sunflower.The resin strip extraction for K was calibrated using common NH4OAC extraction, and recommended for routine analyses because of its simplicity and sensitivity. 展开更多
关键词 CANOLA cation exchange membrane CHICKPEA potassium critical values SUNFLOWER
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Application of Big Data Technology in Evaluation of Operating Status of High-pressure Hydrogenation Heat Exchanger
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作者 Li Lujie Liu Xu +1 位作者 Du Rui Xu Peng 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第3期17-23,共7页
The high-pressure hydrogenation heat exchanger is an impoltmlt equipment of the refinery, but it is exposed tothe problem of leakage caused by ammonium salt corrosion. Therefore, it is very important to evaluate the o... The high-pressure hydrogenation heat exchanger is an impoltmlt equipment of the refinery, but it is exposed tothe problem of leakage caused by ammonium salt corrosion. Therefore, it is very important to evaluate the operating statusof flae hydrogenation heat exchanger. To improve flae method for evaluating the operating status of hydrogenation heat ex-chmagers by using flae traditional method, flais paper proposes a new method for evaluating the operation of hydrogenationheat exchangers based on big data. To address flae noisy data common in flae industry, this paper proposes an automatednoisy interval detection algorithm. To deal with flae problem that the sensor parameters have voluminous and mtrelateddimensions, flais paper proposes a key parameter detection algorithm based on flae Pearson correlation coefficient. Finally,this paper presents a system-based health scoring algorithm based on PCA (Principal Component Analysis) to assist site op-erators in assessing the healfla of hydrogenation heat exchangers. The evaluation of flae operating status of flae hydrorefiningheat exchange device based on big data technology will help the operators to more accurately grasp the status of flae indus-trial system mad have positive guiding significance for the early warning offlae failure. 展开更多
关键词 HYDROGENATION heat exchanger big data state assessment
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Development of Performance Evaluation Technique for Shell-Tube Heat Exchangers
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作者 Se Youl Won Jae Gon Lee 《Journal of Energy and Power Engineering》 2013年第11期2019-2026,共8页
As the operation time of heat exchanger is increased, the thermal performance of them is gradually degraded due to fouling generated by water-borne deposits which are known to reduce the thermal efficiencies. Currentl... As the operation time of heat exchanger is increased, the thermal performance of them is gradually degraded due to fouling generated by water-borne deposits which are known to reduce the thermal efficiencies. Currently, thermal performance management of heat exchangers is more importantly issued for long term operation. Therefore, the performance evaluation techniques are required to improve the present method for the integrity evaluation of heat exchangers because of the exclusion of fouling calculation and the uncertainty analysis. This paper describes the developed thermal performance evaluation technique applied to the safety-related heat exchangers such as component cooling heat exchangers in a nuclear power plants. 展开更多
关键词 Heat exchanger FOULING uncertainty analysis pressure drop.
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Assessing Soil Properties and Landforms in the Mai-Negus Catchment, Northern Ethiopia 被引量:3
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作者 Gebreyesus Brhane TESFAHUNEGN Lulseged TAMENE Paul L.G.VLEK 《Pedosphere》 SCIE CAS CSCD 2016年第5期745-759,共15页
Soil degradation is a serious environmental problem in Ethiopia. However, little information is documented on indicators such as variations in soil properties across different landforms in a catchment. This study was ... Soil degradation is a serious environmental problem in Ethiopia. However, little information is documented on indicators such as variations in soil properties across different landforms in a catchment. This study was aimed to assess soil properties and their changes across sites with different erosion statuses, and identify landscape positions that require prior management attention in the Mai-Negus catchment, northern Ethiopia. Three types of erosion-status sites(stable, eroding and aggrading) were identified using reconnaissance surveys, and then the corresponding soil samples were collected and analyzed. The major soil properties were significantly varied(P ≤ 0.05) among the three erosion-status sites. The highest soil p H, organic carbon, total nitrogen, cation exchange capacity, iron and zinc were recorded from the aggrading sites in the reservoir and valley landforms of the study catchment. A higher bulk density was generally recorded in the eroding sites, whereas a lower value was observed in the aggrading sites. The highest sand content was observed in the eroding sites of the mountain followed by the central ridge landform. The paired mean difference and the correlation matrix of most soil properties between the different erosion statuses also showed significant differences. About 95% of the erosionstatus sites were correctly classified by the discriminant function, indicating that the field survey-based classification was acceptable for decision making. On the basis of this study, suitable interventions should thus be introduced to the prioritized landforms, which are the mountain and central ridge, and eroding sites with severely degraded soil properties across the catchment. 展开更多
关键词 aggrading site discriminant function eroding site erosion status landscape soil property variability stable site
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