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论刑事电子证据的收集制度的建立 被引量:1
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作者 张妍 《法制与经济》 2015年第17期69-70,共2页
新兴科技逐渐渗透到我们的生活中,新的法律问题也随之而来,我国在电子证据方面的立法还处于起步阶段,在司法裁判中法官往往依照"自由心证"主义进行审查。加之缺乏行之有效的统一规范,在收集过程中难免会对其他公民的合法权益... 新兴科技逐渐渗透到我们的生活中,新的法律问题也随之而来,我国在电子证据方面的立法还处于起步阶段,在司法裁判中法官往往依照"自由心证"主义进行审查。加之缺乏行之有效的统一规范,在收集过程中难免会对其他公民的合法权益造成侵害文章将阐释电子证据的概念,对电子证据的特点进行分析,再结合电子证据在司法裁判中的应用分析我国电子证据的地位,对司法实践中如何规范的收集电子证据,如何正确采信电子证据,如何判断电子证据的证据能力等问题展开探讨。分析我国出现的问题并提出解决措施完善电子证据收集和采信制度。 展开更多
关键词 电子证据 合法收集 制度建立
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原油极性组分的吸附与储层润湿性及研究意义 被引量:30
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作者 李素梅 张爱云 王铁冠 《地质科技情报》 EI CAS CSCD 北大核心 1998年第4期65-70,共6页
讨了原油极性组分(非烃、沥青质)的吸附机理及其吸附性、润湿性特征;介绍了NSO极性化合物与润湿性的关系。极性化合物的吸附可能是多种机理共同作用的结果。吸附作用可导致储层润湿性反转,润湿性是决定原油采收率的主要因素。通... 讨了原油极性组分(非烃、沥青质)的吸附机理及其吸附性、润湿性特征;介绍了NSO极性化合物与润湿性的关系。极性化合物的吸附可能是多种机理共同作用的结果。吸附作用可导致储层润湿性反转,润湿性是决定原油采收率的主要因素。通过改变储层润湿性,可能有利于提高原油采收率。极性化合物的吸附等特性在储层润湿性研究、油田开发管理中具有重要意义。 展开更多
关键词 极性化合物 沥青质 润湿性 采收集 储层 油矿床
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提高固井质量技术 被引量:6
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作者 李在胜 崔军 薄和秋 《西部探矿工程》 CAS 2001年第3期57-59,共3页
该项技术研究以提高调整井固井质量为目的 ,研究开发出有利于油田增加采收率、降低开采成本、提高总体经济效益的新固井工艺技术措施。
关键词 封隔器 添加剂 固井工程 采收集 油气井 质量 水泥浆
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低渗油藏二氧化碳混相驱技术研究 被引量:4
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作者 张清正 刘铁桩 +1 位作者 曾贤辉 徐先华 《西部探矿工程》 CAS 2001年第3期60-61,共2页
二氧化碳混相驱是提高原油采收率的一种有效方法 ,该文通过实验室内对文 184块地层流体进行了二氧化碳 /地层原油的压力—组分试验 ,二氧化碳细管驱替试验和长岩芯驱替试验研究 ,并进行了二氧化碳混相驱数值模拟研究 ,确定出文
关键词 采收集 混相驱油 二氧化碳 室内试验 数值模拟 低渗油藏 储层
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提高浅薄层特超稠油资源利用程度的技术途径 被引量:10
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作者 胡常忠 刘新福 《河南石油》 1996年第4期8-13,4,共6页
根据河南油田稠油油藏特点,在对国内外稠油开采方式调研的基础上,提出了高速脉冲注汽吞吐、加密井蒸汽吞吐、间歇蒸汽驱、水平压裂辅助蒸汽驱、出砂冷系以及低频脉冲波强化采油等6项提高浅薄层特超稠油油藏资源利用程度,改善开采效果的... 根据河南油田稠油油藏特点,在对国内外稠油开采方式调研的基础上,提出了高速脉冲注汽吞吐、加密井蒸汽吞吐、间歇蒸汽驱、水平压裂辅助蒸汽驱、出砂冷系以及低频脉冲波强化采油等6项提高浅薄层特超稠油油藏资源利用程度,改善开采效果的技术途径。预测结果表明,通过这些技术的应用,稠油资源利用率和采收率均可望提高一倍。 展开更多
关键词 稠油 资源利用 采收集 油藏工程
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聚合物驱的现状与展望 被引量:2
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作者 王龙 《世界石油工业》 1997年第1期50-51,共2页
目前经济的不景气和边远地区勘探的高成本迫使经营者不断致力于最大限度地开发现有储量。主要方法之一就是提高原油采收率,在延长油田有效开采期的的同时采出更区地储量。本文介绍在大庆和Courtenay油田已获得成功应用的聚合... 目前经济的不景气和边远地区勘探的高成本迫使经营者不断致力于最大限度地开发现有储量。主要方法之一就是提高原油采收率,在延长油田有效开采期的的同时采出更区地储量。本文介绍在大庆和Courtenay油田已获得成功应用的聚合物驱技术。 展开更多
关键词 聚合物驱 提高采收集 油田
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Designing optimal number of receiving traces based on simulation model 被引量:1
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作者 赵虎 武泗海 +4 位作者 杨晶 任达 徐维秀 刘迪鸥 朱鹏宇 《Applied Geophysics》 SCIE CSCD 2017年第1期49-55,189,共8页
Currently, the selection of receiving traces in geometry design is mostly based on the horizontal layered medium hypothesis, which is unable to meet survey requirements in a complex area. This paper estimates the opti... Currently, the selection of receiving traces in geometry design is mostly based on the horizontal layered medium hypothesis, which is unable to meet survey requirements in a complex area. This paper estimates the optimal number of receiving traces in field geometry using a numerical simulation based on a field test conducted in previous research (Zhu et al., 2011). A mathematical model is established for total energy and average efficiency energy using fixed trace spacing and optimal receiving traces are estimated. Seismic data acquired in a complex work area are used to verify the correctness of the proposed method. Results of model data calculations and actual data processing show that results are in agreement. This indicates that the proposed method is reasonable, correct, sufficiently scientific, and can be regarded as a novel method for use in seismic geometry design in complex geological regions. 展开更多
关键词 Survey design GEOMETRY receiving trace number optimization forward modeling
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Seismic data analysis based on spatial subsets 被引量:2
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作者 蔡希玲 刘学伟 +2 位作者 李虹 钱宇明 吕英梅 《Applied Geophysics》 SCIE CSCD 2009年第4期384-392,395,共10页
There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from ... There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from common shot gathers or other datasets located at certain points or along lines. We propose a novel method in this paper to observe seismic data on time slices from spatial subsets. The composition of a spatial subset and the unique character of orthogonal or oblique subsets are described and pre-stack subsets are shown by 3D visualization. In seismic data processing, spatial subsets can be used for the following aspects: (1) to check the trace distribution uniformity and regularity; (2) to observe the main features of ground-roll and linear noise; (3) to find abnormal traces from slices of datasets; and (4) to QC the results of pre-stack noise attenuation. The field data application shows that seismic data analysis in spatial subsets is an effective method that may lead to a better discrimination among various wavefields and help us obtain more information. 展开更多
关键词 spatial subset 3D visualization high density sampling noise attenuation data analysis
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蒜薹蒜头两用蒜丰产栽培技术(上)
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作者 韦春彬 《农家致富》 2018年第17期31-32,共2页
蒜薹、蒜头两用蒜生产可以有效提高单位土地效益。江苏省射阳县大蒜栽培主产品一般为蒜薹,兼收蒜头。蒜薹采收集中,主要通过贮藏保鲜以后陆续上市,栽培上应选择优质、丰产、耐贮、抗病的品种,如射阳白蒜、三月黄等。
关键词 丰产栽培技术 蒜头 蒜薹 贮藏保鲜 射阳县 江苏省 采收集 大蒜
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弧东油田馆5^2+3层小井距注水开发全过程现场试验研究的初步认识
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作者 屈智坚 《陆相石油地质》 1990年第1期43-56,共14页
高渗透、高粘度、河流相沉积的亲水砂岩馆5^2+3油层小井距注水开发全过程现场试验,为占胜利油区近三分之一储量的馆陶组油藏的开发与调整、动态预测、长远规划等提供了一定的实践依据。试验研究表明:注开发中含水期以前,生产时间短... 高渗透、高粘度、河流相沉积的亲水砂岩馆5^2+3油层小井距注水开发全过程现场试验,为占胜利油区近三分之一储量的馆陶组油藏的开发与调整、动态预测、长远规划等提供了一定的实践依据。试验研究表明:注开发中含水期以前,生产时间短,含水上升较快,产油能力旺盛,采油指数逐渐上升至最高值之后下降到初期水平,见水后含水上升率逐渐增至最高值,采出近60%的可采储量。高含水期生产时间长,采油指数递减,含水上升减缓,产液能力增强,注水利用率低,可采出40%多的可采储量。原油密度和粘度有较小幅度的增加,天然气和组分含量变化较小。注入低矿化度水后油田水性质逐渐淡化;油层见水厚度大,水淹面积大,层内初期见水状况受渗透率纵向发布控制。驱油效率低,开发前期波及系数增长快,水驱采收率可达45.7%。 展开更多
关键词 弧东油田 小井距注水开发 试验 油指数 驱油效率 采收集
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秋花椰菜配套栽培技术
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《山东蔬菜》 2006年第2期33-33,共1页
在种植业调整中秋花椰菜(秋菜花)的面积正在不断扩大,许多农民朋友已得到了实惠。其优点是:苗期耐热,生长期较短.采收集中,选用不同品种可分期上市;其次是产量稳,销路好。根据不同品种的生长期可在9月份后不断收获上市,对生... 在种植业调整中秋花椰菜(秋菜花)的面积正在不断扩大,许多农民朋友已得到了实惠。其优点是:苗期耐热,生长期较短.采收集中,选用不同品种可分期上市;其次是产量稳,销路好。根据不同品种的生长期可在9月份后不断收获上市,对生长期稍长的品种可作为延迟栽培,稍加保护就可供应至新年。 展开更多
关键词 秋花椰菜 配套栽培技术 生长期 延迟栽培 秋菜花 种植业 采收集 品种 上市 苗期
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Retrieval of inherent optical properties of the Yellow Sea and East China Sea using a quasi-analytical algorithm 被引量:7
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作者 青松 唐军武 +1 位作者 崔廷伟 张杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第1期33-45,共13页
We tested and modified the quasi-analytical algorithm (QAA) using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coef... We tested and modified the quasi-analytical algorithm (QAA) using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coefficients of typical coastal waters. The average percentage difference (APD) is in a range of 13.9%-38.5% for the total absorption coefficient (13.9% at 440 nm), and differences in particle backscattering coefficient bbp(2) are less than 50% (in the case of the updated QAA). To obtain improved results, we modified the QAA by adjusting the empirical relationships. The modified algorithm is then applied to the field data to test its performance. The APDs were 44.7%-46.6% for bbp(λ) and 9.9%-32.8% (9.9% at 555 nm) for the total absorption coefficient. This indicates that the modified QAA derives better results. We also used the modified model to derive phytoplankton pigment absorption (aph) and detritus and CDOM absorption (aug) coefficients. The APDs for aph and a dg at 440 nm are 37.1% and 19.8%. In this paper, we discuss error sources using the measured dataset. More independent field data can improve this algorithm and derive better results. 展开更多
关键词 inherent optical properties Yellow Sea and the East China Sea quasi-analytical algorithm
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Energy Efficient Data Collection in Hierarchical Wireless Sensor Networks 被引量:2
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作者 Zhang Chun Fei Shumin Zhou Xingpeng 《China Communications》 SCIE CSCD 2012年第9期79-88,共10页
The majority of the energy consumption by the sensors is the energy requirement for data transmission in Wireless Sensor Networks (WSNs). Therefore, introducing mobile collectors to collect data instead of nmlti-hop... The majority of the energy consumption by the sensors is the energy requirement for data transmission in Wireless Sensor Networks (WSNs). Therefore, introducing mobile collectors to collect data instead of nmlti-hop data relay is essential. However, for rmny proposed data gathering ap-proaches, long data deNNy is the train problenm. Hence, the problem of how to decrease the energy consumption and the data deNNy needs to be solved. In this paper, a low deNNy data collection mechanism using multiple mobile collectors is pro- posed. First, a self-organization clustering algorithm is designed. Second, sensor nodes are organized into three-level clusters. Then a collection strategy based on the hierarchical structure is proposed, which includes two rules to dispatch mobile collec- tors rationally. Simulation results show that the proposed mechanism is superior to other existing approaches in terms of the reduction in energy ex-penditure and the decrease in data deNNy. 展开更多
关键词 WSNS energy consumption rrmltiplemobile collectors data delay
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Data Aggregation Scheduling with Guaranteed Lifetime and Efficient Latency in Wireless Sensor Networks 被引量:4
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作者 Chen Zhengyu Yang Geng +3 位作者 Chen Lei Xu Jian Wang Haiyong Yang Zhen 《China Communications》 SCIE CSCD 2012年第9期11-21,共11页
In scenarios of real-time data collection of long-term deployed Wireless Sensor Networks (WSNs), low-latency data collection with long net- work lifetime becomes a key issue. In this paper, we present a data aggrega... In scenarios of real-time data collection of long-term deployed Wireless Sensor Networks (WSNs), low-latency data collection with long net- work lifetime becomes a key issue. In this paper, we present a data aggregation scheduling with guaran- teed lifetime and efficient latency in WSNs. We first Construct a Guaranteed Lifetime Mininmm Ra- dius Data Aggregation Tree (GLMRDAT) which is conducive to reduce scheduling latency while pro- viding a guaranteed network lifetime, and then de-sign a Greedy Scheduling algorithM (GSM) based on finding the nmzximum independent set in conflict graph to schedule he transmission of nodes in the aggregation tree. Finally, simulations show that our proposed approach not only outperfonm the state-of-the-art solutions in terms of schedule latency, but also provides longer and guaranteed network lifetilre. 展开更多
关键词 WSNs data aggregation aggregationscheduling network lifetime LATENCY
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Maximum Data Collection Rate in Rechargeable Wireless Sensor Networks with Multiple Sinks 被引量:2
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作者 GAO Demin LIN Haifeng +1 位作者 LIU Yunfei WU Guoxin 《China Communications》 SCIE CSCD 2016年第2期95-108,共14页
In rechargeable wireless sensor networks, a sensor cannot be always benefi cial to conserve energy when a network can harvest excessive energy from the environment due to its energy replenished continually and limited... In rechargeable wireless sensor networks, a sensor cannot be always benefi cial to conserve energy when a network can harvest excessive energy from the environment due to its energy replenished continually and limited energy storage capacity. Therefore, surplus energy of a node can be utilized for strengthening packet delivery efficiency and improving data collection rate. In this work, we propose an algorithm to compute an upper data generation rate that maximizes it as an optimization problem for a network with multiple sinks, which is formulated as a linear programming problem. Subsequently, a dual problem by introducing Lagrange multipliers is constructed, and subgradient algorithms are used to solve it in a distributed manner. The resulting algorithms are guaranteed to converge to an optimal data generation rate, which are illustrated by an example in which an optimum data generation rate is computed for a network of randomly distributed nodes. Through extensive simulation and experiments, we demonstrate our algorithm is efficient to maximize data collection rate in rechargeable wireless sensor networks. 展开更多
关键词 wireless sensor networks maximumdata collection rate linear programming rechargeable-WSNs
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Solid phase microextraction(SPME) sampling under turbulent conditions and for the simultaneous collecting of tracer gases 被引量:1
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作者 Underwood Susanne W. Jong Edmund C. +3 位作者 Luxbacher Kray D. Sarver Emily A. Ripepi Nino S. Mc Nair Harold M. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期559-563,共5页
Solid phase microextraction (SPME) is a solvent-flee method of sample collection. SPME is an appealing method for sample collection because it is designed for the sampling of trace level analytes with short sampling... Solid phase microextraction (SPME) is a solvent-flee method of sample collection. SPME is an appealing method for sample collection because it is designed for the sampling of trace level analytes with short sampling times in a variety of environments. Additionally, SPME can be used to directly deliver a sample to a gas chromatograph (GC) for analysis by means of thermal desorption. In this paper, the performance of SPME under dynamic conditions was investigated. Additionally, the competence of SPME sampling for the simultaneous analysis of multiple trace analytes was also evaluated. This work is discussed in the context of underground mine ventilation surveys but is applicable to any industry in which ventilation circuits must be evaluated. The results of this paper showed that the performance of the 100 ~m PDMS SPME fiber was both precise and rapid under dynamic conditions. This SPME fiber was also able to simultaneously collect sulfur hexafluoride (SF6) and perfluoromethylcyclohexane (PMCH) with adequate sensitivity. 展开更多
关键词 Solid phase microextraction Sulfur hexafluoride Perfluoromethylcyclohexane Tracer gas Mine ventilation Air sampling
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Energy-Efficient Mobile Data Collection Adopting Node Cooperation in an Underwater Acoustic Sensor Network
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作者 Yougan Chen Xiaoting Jin Xiaomei Xu 《China Communications》 SCIE CSCD 2017年第6期32-42,共11页
This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node ind... This paper considers an underwater acoustic sensor network with one mobile surface node to collect data from multiple underwater nodes,where the mobile destination requests retransmission from each underwater node individually employing traditional automatic-repeat-request(ARQ) protocol.We propose a practical node cooperation(NC) protocol to enhance the collection efficiency,utilizing the fact that underwater nodes can overhear the transmission of others.To reduce the source level of underwater nodes,the underwater data collection area is divided into several sub-zones,and in each sub-zone,the mobile surface node adopting the NC protocol could switch adaptively between selective relay cooperation(SRC) and dynamic network coded cooperation(DNC) .The difference of SRC and DNC lies in whether or not the selected relay node combines the local data and the data overheard from undecoded node(s) to form network coded packets in the retransmission phase.The NC protocol could also be applied across the sub-zones due to the wiretap property.In addition,we investigate the effects of different mobile collection paths,collection area division and cooperative zone design for energy saving.The numerical results showthat the proposed NC protocol can effectively save energy compared with the traditional ARQ scheme. 展开更多
关键词 underwater acoustic sensor networks mobile data collection node cooperation cooperative communications energy efficiency
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Design of ADCS for Efficient Meter Data Collection and Management
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作者 Nam-Joon Jung II-Kwon Yang +2 位作者 Seung-Hwan Choi Chang-Hun Chae Young-Taek Jin 《Journal of Energy and Power Engineering》 2012年第6期993-998,共6页
ADCS (automated data collection system) is the element of MDMS (meter data management system) and a module in charge of collecting the data from DCUs (data collection units) or meters in AMI (advanced metering ... ADCS (automated data collection system) is the element of MDMS (meter data management system) and a module in charge of collecting the data from DCUs (data collection units) or meters in AMI (advanced metering infrastructure)-based interactive two-way communications infrastructure. In this study, ADCS's functions for K-AMI (Korean Advanced Metering Infrastructure) were analyzed and the logical design of ADCS which is suitable for the requirements was suggested. A massive data collection and management functions was defined as very important functions of ADCS to meet optimal data processing mechanism. ADCS was designed for support about the fuctions of data collection and transfer, large capacity data processing, interactive services, parallel processing, etc.. Also, ADCS has roles of protocols exchange and gateway for service support in addition to data collection in AMI environment. 展开更多
关键词 AMI MDMS ADCS DCU smart metering.
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Improved Circular Correlation Methods for Acquisition in Software GPS Receiver
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作者 Vandana Patel Pankaj Shukla Mithilesh Kumar 《Computer Technology and Application》 2011年第5期389-395,共7页
In this paper the authors explore the Global Positioning System (GPS) signal acquisition and tracking algorithms used in software GPS receiver. Acquisition time is the most important parameter in evaluating the perf... In this paper the authors explore the Global Positioning System (GPS) signal acquisition and tracking algorithms used in software GPS receiver. Acquisition time is the most important parameter in evaluating the performance of a software GPS receiver in terms of its speed. A trade-off study is done to seek a good balance between the acquisition accuracy and the processing time. The frequency-domain acquisition method by circular correlation, used in a software GPS receiver, has been improved by studying the power spectrum of the Coarse Acquisition (C/A) code alone. The analysis of C/A code reveals that its power spectrum is symmetrical; hence only half the points are required to perform circular correlation. Besides, either half of the spectrum is asymmetrical where a larger amount of power is concentrated in almost one-quarter of the spectrum on its either sides. This further reduces the number of points used to perform correlation. Comparative results of MATLAB simulation of full-size, half-size and quarter-size circular correlation done on actual data stored on hard disk are provided, and they agree with those obtained using GPS receiver. Further reduction in acquisition time has been achieved by investigating the effect of length of the noncoherent pre-integration period. The improved acquisition methods pave way for further development of new algorithms to enhance software GPS receiver performance. 展开更多
关键词 Global positioning system (GPS) software GPS receiver coarse acquisition (C/A) code signal acquisition circular correlation signal power spectrum.
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Demonstration of Magnetic Energy Harvesting from Electrical Appliances
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作者 Kunihisa Tashiro Hiroyuki Wakiwaka Syoichiro Shimada 《Journal of Energy and Power Engineering》 2014年第3期568-572,共5页
The purpose of this study is to use magnetic field of 50/60 Hz up to 0.2 mT for energy source. This paper focuses on magnetic energy harvesting from electrical appliances which can be also used for power consumption m... The purpose of this study is to use magnetic field of 50/60 Hz up to 0.2 mT for energy source. This paper focuses on magnetic energy harvesting from electrical appliances which can be also used for power consumption monitoring. The magnetic energy harvesting device consists of an energy harvesting module, Cockcroft-Walton circuit and storage capacitor. First of all, typical magnetic fields around several electrical appliances are investigated. In order to harvest 10 mJ energy, the shape of magnetic flux concentration flange in energy harvesting module and number of steps in Cockcroft-Walton circuit are considered. From experimental results, magnetic energy harvesting of 17 mJ from a refrigerator is successfully demonstrated. 展开更多
关键词 Magnetic energy harvesting electrical appliances environmental magnetic field Cockcrofl-Walton circuit magneticflange.
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