期刊文献+
共找到20篇文章
< 1 >
每页显示 20 50 100
新高考中选考科目成绩计分方案的探讨 被引量:2
1
作者 王凡 《湖北师范大学学报(自然科学版)》 2019年第2期111-114,共4页
新高考采用“6选3”(“7选3”)的选科方案,需要有与之相适应的成绩计分方案。当前已经实施新高考培养模式的省市中,有六个省(市)已经公布了选考科目的计分方案。这些计分方案存在着诸如分数扭曲、等级比例难以把握、诱导选科博弈和变相... 新高考采用“6选3”(“7选3”)的选科方案,需要有与之相适应的成绩计分方案。当前已经实施新高考培养模式的省市中,有六个省(市)已经公布了选考科目的计分方案。这些计分方案存在着诸如分数扭曲、等级比例难以把握、诱导选科博弈和变相降低选考科目重要性等问题,仍然需要在实践探索中有针对性地进行一些相应的改进。可能的改进措施有减少等级划分、结合线性赋分、动态调整等级比例、引入外部参考、适当提高分数全差等。 展开更多
关键词 新高考 选考科目 成绩计分方案
下载PDF
慢性肝炎炎症活动度及纤维化程度计分方案 被引量:388
2
作者 王泰龄 刘霞 +5 位作者 周元平 何静雯 张晶 李宁章 段钟平 王宝恩 《中华肝脏病杂志》 CAS CSCD 1998年第4期195-197,共3页
目的为便于统计、分析、比较,制定一个合理的慢性肝炎炎症活动度及纤维化程度的半定量计分方案。方法以Knodel的炎症活动度指数及Chevalier的纤维化半定量计分方案为基础,进行修改。应用近期系列肝穿刺标本分析验证修... 目的为便于统计、分析、比较,制定一个合理的慢性肝炎炎症活动度及纤维化程度的半定量计分方案。方法以Knodel的炎症活动度指数及Chevalier的纤维化半定量计分方案为基础,进行修改。应用近期系列肝穿刺标本分析验证修改后方案的适用性。结果①制定了慢性肝炎半定量计分方案及计算公式;②96例慢性肝炎炎症活动度和纤维化程度计分结果与分级分期明显相关,相关系数分别为0963和0874(P<005);③观察对比了34例慢性乙型肝炎治疗前后各项病变的计分,证明该计分方案能较好地反映病变程度,便于疗效统计分析比较;量化数值能反映出同一级/期内病变程度差异。结论慢性肝炎计分方案,能较好地反映病变程度,特别适用于疗效的统计、分析、比较。 展开更多
关键词 计分方案 慢性 肝炎 纤维化 炎症 活动度 诊断
原文传递
改革赋分方案实现高考评价科学与录取公平
3
作者 黄海龙 《教育教学论坛》 2020年第31期7-10,共4页
新高考对选考(或再选)学科采用等级赋分,将选考(或再选)学科的等级分与其他学科的原始分求和后作为高考升学的录取依据。新高考与传统高考的计分方案不同,对同一考生群体的评价结果与综合排序不具一致性,相差大。针对新高考赋分弊端与... 新高考对选考(或再选)学科采用等级赋分,将选考(或再选)学科的等级分与其他学科的原始分求和后作为高考升学的录取依据。新高考与传统高考的计分方案不同,对同一考生群体的评价结果与综合排序不具一致性,相差大。针对新高考赋分弊端与计分缺陷,提出通过实施学科排序成绩的计分改革来实现高考评价科学与录取公平。 展开更多
关键词 新高考 计分方案 评价科学 录取公平
下载PDF
医学实习生临床技能强化培训效果评价 被引量:4
4
作者 朱扣云 彭文 +4 位作者 王宁华 李敏 韩吉 邢丽娜 陈贻训 《中国高等医学教育》 2008年第5期110-112,共3页
目的:为提高高等医学院校临床医学生的毕业实践能力,对临床实习生进行临床技能强化培训,并进行效果评价。材料:在医院毕业实习的35名实习学生158人次培训考核资料。方法:考核内容包括病史采集、全面体格检查、诊疗计划和水平、病历书写... 目的:为提高高等医学院校临床医学生的毕业实践能力,对临床实习生进行临床技能强化培训,并进行效果评价。材料:在医院毕业实习的35名实习学生158人次培训考核资料。方法:考核内容包括病史采集、全面体格检查、诊疗计划和水平、病历书写等,设计了技能考核2级权重计分方案进行评估。结果:经过临床实习强化培训,合计得分由2月份的82.05分,提高到6月份的96.35分。结论:通过5个月的实习生临床技能强化培训,临床实践能力有了明显的提高。 展开更多
关键词 临床技能 强化培训 实践能力 2级权重计分方案 效果评价
下载PDF
导游专业计算机教学中任务性学习的研究与实践
5
作者 赵欢 《旅游学刊》 CSSCI 北大核心 2005年第S1期207-210,共4页
素质教育的一个重要部分就是学生综合应用能力及探究能力的培养。笔者针对导游专业的特点,在计算机基础教学中引入任务性学习方式,改善了教学效果,提高了该专业学生的计算机综合应用能力及自主探究能力。
关键词 任务性学习 任务 综合应用能力 模拟导游大赛计分方案
下载PDF
Application of the optimal Latin hypercube design and radial basis function network to collaborative optimization 被引量:16
6
作者 ZHAO Min CUI Wei-cheng 《Journal of Marine Science and Application》 2007年第3期24-32,共9页
Improving the efficiency of ship optimization is crucial for modem ship design. Compared with traditional methods, multidisciplinary design optimization (MDO) is a more promising approach. For this reason, Collabora... Improving the efficiency of ship optimization is crucial for modem ship design. Compared with traditional methods, multidisciplinary design optimization (MDO) is a more promising approach. For this reason, Collaborative Optimization (CO) is discussed and analyzed in this paper. As one of the most frequently applied MDO methods, CO promotes autonomy of disciplines while providing a coordinating mechanism guaranteeing progress toward an optimum and maintaining interdisciplinary compatibility. However, there are some difficulties in applying the conventional CO method, such as difficulties in choosing an initial point and tremendous computational requirements. For the purpose of overcoming these problems, optimal Latin hypercube design and Radial basis function network were applied to CO. Optimal Latin hypercube design is a modified Latin Hypercube design. Radial basis function network approximates the optimization model, and is updated during the optimization process to improve accuracy. It is shown by examples that the computing efficiency and robustness of this CO method are higher than with the conventional CO method. 展开更多
关键词 multidisciplinary design optimization (MDO) collaborative optimization (CO) optimal Latin hypercube design radial basis function network APPROXIMATION
下载PDF
NEW METHOD OF FORMATION DESIGN FOR BOTH GMTI AND INSAR USING DISTRIBUTED SATELLITES 被引量:1
7
作者 Yuan Hao Zhou Yinqing Li Jingwen Sun Muhan 《Journal of Electronics(China)》 2007年第6期821-827,共7页
This letter proposes a method for designing a specific formation of satellites where the flying motion only exists in a circle orbit plane of the reference satellite, which means that the orbit eccentricity is zero. T... This letter proposes a method for designing a specific formation of satellites where the flying motion only exists in a circle orbit plane of the reference satellite, which means that the orbit eccentricity is zero. This method combines the Hill equation, the Kepler equation, and the geometrical inea^ing of orbit elements. It creates the redundancy condition to simplify the deducing process, utilizes multiple conditions to solve the orbit elements for the satellite formation, and obtains the analytical relationship of the orbit elements for the formation satellites with the formation parameters and the orbit elements of the reference satellite. Using these formulations, the orbit elements and formation parameters for the formation satellites can be solved for the given orbit elements of the reference satellite. The letter describes the proposed double-ellipse formation for both GMTI and InSAR, and the validity of the formation is demonstrated via simulation. 展开更多
关键词 Synthetic Aperture Radar (SAR) Double-ellipse formation Dual-interferometry Orbit design
下载PDF
UTILITY OPTIMIZATION SCHEDULING FOR MULTI-POINT VIDEO SURVEILLANCE IN UBIQUITOUS NETWORK 被引量:1
8
作者 Zhang Chen Huang Liusheng Xu Hongli 《Journal of Electronics(China)》 2013年第1期1-8,共8页
Resource allocation is an important problem in ubiquitous network. Most of the existing resource allocation methods considering only wireless networks are not suitable for the ubiquitous network environment, and they ... Resource allocation is an important problem in ubiquitous network. Most of the existing resource allocation methods considering only wireless networks are not suitable for the ubiquitous network environment, and they will harm the interest of individual users with instable resource requirements. This paper considers the multi-point video surveillance scenarios in a complex network environment with both wired and wireless networks. We introduce the utility estimated by the total costs of an individual network user. The problem is studied through mathematical modeling and we propose an improved problem-specific branch-and-cut algorithm to solve it. The algorithm follows the divide-and-conquer principle and fully considers the duality feature of network selection. The experiment is conducted by simulation through C and Lingo. And it shows that compared with a centralized random allocation scheme and a cost greed allocation scheme, the proposed scheme has better per- formance of reducing the total costs by 13.0% and 30.6% respectively for the user. 展开更多
关键词 Ubiquitous network Multi-point video surveillance Resource allocation
下载PDF
SPSM and its application in cylindrical shells 被引量:2
9
作者 聂武 周素莲 彭辉 《Journal of Marine Science and Application》 2008年第1期40-47,共8页
In naval architectures, the structure of prismatic shell is used widely. But there is no suitable method to analyze this kind of structure. Stiffened prismatic shell method (SPSM) presented in this paper, is one of th... In naval architectures, the structure of prismatic shell is used widely. But there is no suitable method to analyze this kind of structure. Stiffened prismatic shell method (SPSM) presented in this paper, is one of the harmonic semi-analytic methods. Theoretically, strong stiffened structure can be analyzed economically and accurately. SPSM is based on the analytical solution of the governing differential equations for orthotropic cylindrical shells. In these differential equations, the torsional stiffness, bending stiffness and the exact position of each stiffener are taken into account with the Heaviside singular function. An algorithm is introduced, in which the actions of stiffeners on shells are replaced by external loads at each stiffener position. Stiffened shells can be computed as non-stiffened shells. Eventually, the displacement solution of the equations is acquired by the introduction of Green function. The stresses in a corrugated transverse bulkhead without pier base of an oil tanker are computed by using SPSM. 展开更多
关键词 stiffened shell stress analysis singular function Green function corrugated bulkhead
下载PDF
Impacts of Total Energy Consumption Control and Energy Quota Allocation on China′s Regional Economy Based on A 30-region Computable General Equilibrium Analysis
10
作者 LI Na SHI Minjun +1 位作者 SHANG Zhiyuan YUAN Yongna 《Chinese Geographical Science》 SCIE CSCD 2015年第6期657-671,共15页
This paper examined the impacts of the total energy consumption control policy and energy quota allocation plans on China′s regional economy. This research analyzed the influences of different energy quota allocation... This paper examined the impacts of the total energy consumption control policy and energy quota allocation plans on China′s regional economy. This research analyzed the influences of different energy quota allocation plans with various weights of equity and efficiency, using a dynamic computable general equilibrium(CGE) model for 30 province-level administrative regions. The results show that the efficiency-first allocation plan costs the least but widens regional income gap, whereas the outcomes of equity-first allocation plan and intensity target-based allocation plan are similar and are both opposite to the efficiency-first allocation plan′ outcome. The plan featuring a balance between efficiency and equity is more feasible, which can bring regional economic losses evenly and prevent massive interregional migration of energy-related industries. Furthermore, the effects of possible induced energy technology improvements in different energy quota allocation plans were studied. Induced energy technology improvements can add more feasibility to all allocation plans under the total energy consumption control policy. In the long term, if the policy of the total energy consumption control continues and more market-based tools are implemented to allocate energy quotas, the positive consequences of induced energy technology improvements will become much more obvious. 展开更多
关键词 total energy consumption control energy quota allocation computable general equilibrium (CGE) model induced energytechnology improvements
下载PDF
Design and analysis of the reliability of on-board computer system based on Markov-model
11
作者 马秀娟 曹喜滨 赵国良 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第1期17-20,共4页
An on-board computer system should have such advantages as light weight,small volume and low power to meet the demand of micro-satellites. This paper, based on specific characteristics of Stereo Mapping Micro-Satellit... An on-board computer system should have such advantages as light weight,small volume and low power to meet the demand of micro-satellites. This paper, based on specific characteristics of Stereo Mapping Micro-Satellite (SMMS), describes the on-board computer system with its advantage of having centralized and distributed control in the same system and analyzes its reliability based on a Markov model in order to provide a theoretical foundation for a reliable design. The on-board computer system has been put into use in principle prototype model of Stereo Mapping Micro-Satellite and has already been debugged. All indexes meet the requirements of the design. 展开更多
关键词 markov model computer system RELIABILITY MICRO-SATELLITE
下载PDF
Power-optimal encoding for low-power address bus
12
作者 孙海珺 邵志标 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第5期652-656,共5页
This paper presented a novel bus encoding method to reduce the switching activity on address buses and hence reduce power dissipation. Dynamic-sorting encoding(DSE) method reduces the power dissipation of address bus ... This paper presented a novel bus encoding method to reduce the switching activity on address buses and hence reduce power dissipation. Dynamic-sorting encoding(DSE) method reduces the power dissipation of address bus based on the dynamic reordering of the modified offset address bus lines. This method reorders the ten least significant bits of offset address according to the range of offset address, and the optimal sorting pattern is transmitted through the high bits of address bus without the need for redundant bus lines. The experimental results by using an instruction set simulator and SPEC2000 benchmarks show that DSE method can reduce signal transitions on the address bus by 88.2%, and the actual overhead of the encoder circuit is estimated after encoder is designed and synthesized in 0.18-μm CMOS technology. The results show that DSE method outperforms the low-power encoding schemes presented in the past. 展开更多
关键词 bus encoding switching activity address bus LOW-POWER CMOS
下载PDF
Research on probability distribution of port cargo throughput
13
作者 孙亮 谭德荣 《Journal of Marine Science and Application》 2008年第1期65-68,共4页
In order to more accurately examine developing trends in gross cargo throughput, we have modeled the probability distribution of cargo throughput. Gross cargo throughput is determined by the time spent by cargo ships ... In order to more accurately examine developing trends in gross cargo throughput, we have modeled the probability distribution of cargo throughput. Gross cargo throughput is determined by the time spent by cargo ships in the port and the operating efficiency of handling equipment. Gross cargo throughput is the sum of all compound variables determining each aspect of cargo throughput for every cargo ship arriving at the port. Probability distribution was determined using the Wald equation. The results show that the variability of gross cargo throughput primarily depends on the different times required by different cargo ships arriving at the port. This model overcomes the shortcoming of previous models: inability to accurately determine the probability of a specific value of future gross cargo throughput. Our proposed model of cargo throughput depends on the relationship between time required by a cargo ship arriving at the port and the operational capacity of handling equipment at the port. At the same time, key factors affecting gross cargo throughput are analyzed. In order to test the efficiency of the model, the cargo volume of a port in Shandong Province was used as an example. In the case study the actual results matched our theoretical analysis. 展开更多
关键词 cargo throughput Wald equation mathematical modeling
下载PDF
Vehicle Crashworthiness Simulation Based on Virtual Design of Auto-body 被引量:2
14
作者 张晓云 金先龙 +4 位作者 孙奕 林忠钦 周长英 艾维全 王仕达 《Journal of Donghua University(English Edition)》 EI CAS 2004年第2期63-68,共6页
Vehicle crashworthiness simulation is the main component of the virtual auto-body design. One developing commercial vehicle was simulated on crashworthiness by the non-linear finite element method. The bumper crashwor... Vehicle crashworthiness simulation is the main component of the virtual auto-body design. One developing commercial vehicle was simulated on crashworthiness by the non-linear finite element method. The bumper crashworthiness at the speed of 8 km/h was analyzed and valuated. On the other hand, the deformation of the auto-body, the movement of the steering wheel and the dynamic responses of the occupant at the initial velocity of 50 km/h were studied. The results appear that the design of the vehicle could be improved on structure and material. Finally, the frontal longitudinal beam, the main energy-absorbing part of the auto-body, was optimized on structure. Simulation results also show that applying new material, such as high strength steel, and new manufacture techniques, such as tailor-welded blanks could improve the crashworthiness of the vehicle greatly. 展开更多
关键词 Auto-body SIMULATION OPTIMIZATION CRASHWORTHINESS Finite Element Method
下载PDF
Optimization of Selecting Air Conditioning Cold/Heat Sources with Grey Relation Analysis
15
作者 曹国庆 涂光备 《Transactions of Tianjin University》 EI CAS 2006年第3期229-234,共6页
Selection of air conditioning(AC) cold/heat sources generally concerns about certain aspects and cannot reveal the whole profile of the problems. Grey relation analysis (GRA) is a data processing method to categor... Selection of air conditioning(AC) cold/heat sources generally concerns about certain aspects and cannot reveal the whole profile of the problems. Grey relation analysis (GRA) is a data processing method to categorize the correlation extent of compared sequences and a certain reference sequence in a system with uncertain information. It is applied to evaluating and selecting AC cold/heat sources from four main aspects, which are technology, economy, reliability, and operation and management. Case study shows that the result for selecting AC cold/heat sources with the GRA method can be more reasonable and convincible. Thus it offers a new approach for designers in heating, ventilating and air conditioning field to compare and evaluate different AC cold/heat sou rces. 展开更多
关键词 air conditioning cold/heat sources: design scheme: optimal selection: grey relation analysis evaluation factor
下载PDF
Actual implementation of spectrum-sharing systems in rayleigh fading channels~
16
作者 裴二荣 Wang Sheng Zhang Zhizhong 《High Technology Letters》 EI CAS 2012年第2期145-150,共6页
In actual implementation of spectrum sharing systems, due to the selfishness of primary users, primary users often refuse the access of secondary users to their licensed spectrum bands even if the access of secondary ... In actual implementation of spectrum sharing systems, due to the selfishness of primary users, primary users often refuse the access of secondary users to their licensed spectrum bands even if the access of secondary users doesn't affect their transmission. Aimed at the selfishness problem of primary users, a seller's market trading mechanism is introduced which can not only stimulate primary users to tolerate larger interference power but also give the primary users an appropriate compensation at the same time, and which has very important practical significance. Based on the mechanism, the achievable maximal gross profit of secondary users and their optimal power allocation scheme in the Rayleigh fading environment are derived, and the interference price of primary users and the average revenue of secondary users' impact on them are also studied. Numerical calculation results are conducted to verify our theoretical results. 展开更多
关键词 cognitive radio spectrum sharing power allocation seller's market trading mechanism CONVEXOPTIMIZATION
下载PDF
Distributed Key Management Scheme against Sybil Attacks of Wireless Sensor Network
17
作者 Xu Junfeng Wang Yongjian 《China Communications》 SCIE CSCD 2012年第5期55-63,共9页
Wireless sensor network nodes (WSN nodes) have limited computing power, storage ca-pacity, conmmunication capabilities and energy and WSN nodes are easy to be paralyzed by Sybil at- tack. In order to prevent Sybil a... Wireless sensor network nodes (WSN nodes) have limited computing power, storage ca-pacity, conmmunication capabilities and energy and WSN nodes are easy to be paralyzed by Sybil at- tack. In order to prevent Sybil attacks, a new key distribution scheme for wireless sensor networks is presented. In this scheme, the key inforrmtion and node ID are associated, and then the attacker is dif-ficult to forge identity ID and the key inforrmtion corresponding to ID can not be forged. This scheme can use low-power to resist the Syhil attack and give full play to the resource advantages of the cluster head. The computing, storage and corrn^ni- cation is rminly undertaken by the cluster head o- verhead to achieve the lowest energy consumption and resist against nodes capture attack. Theoretical analysis and experimental results show that com- pared with the traditional scheme presented in Ref. [14], the capture rate of general nodes of cluster re-duces 40%, and the capture rate of cluster heads reduces 50%. So the scheme presented in this pa-per can improve resilience against nodes capture at- tack and reduce node power consumption. 展开更多
关键词 WSN sybil attack key distribution CLUSTER
下载PDF
Cross-Layer Scheduling Design for Multimedia Applications over Cognitive Ad Hoc Networks
18
作者 YANG Libiao ZHAO Honglin JIA Min 《China Communications》 SCIE CSCD 2014年第7期99-109,共11页
In this paper,we study cross-layer scheduling scheme on multimedia application which considers both streaming traffic and data traffic over cognitive ad hoc networks.A cross-layer design is proposed to optimize SU'... In this paper,we study cross-layer scheduling scheme on multimedia application which considers both streaming traffic and data traffic over cognitive ad hoc networks.A cross-layer design is proposed to optimize SU's utility,which is used as an approach to balance the transmission efficiency and heterogeneous traffic in cognitive ad hoc networks.A framework is provided for utility-based optimal subcarrier assignment,power allocation strategy and corresponding modulation scheme,subject to the interference threshold to primary user(PU) and total transmit power constraint.Bayesian learning is adopted in subcarrier allocation strategy to avoid collision and alleviate the burden of information exchange on limited common control channel(CCC).In addition,the M/G/l queuing model is also introduced to analyze the expected delay of streaming traffic.Numerical results are given to demonstrate that the proposed scheme significantly reduces the blocking probability and outperforms the mentioned single-channel dynamic resource scheduling by almost 8%in term of system utility. 展开更多
关键词 cognitive ad hoc networks CROSS-LAYER multimedia application common controlchannel
下载PDF
Statistical Properties of The Exponentiated Nakagami Distribution
19
作者 Adepoju K.A Chukwu A.U and Shittu, O.I 《Journal of Mathematics and System Science》 2014年第3期180-185,共6页
This paper is an improvement over beta-Nakagami distribution developed by Shittu and Adepoju (2013). Here we propose the addition of one parameter to the two parameter continuous Nakagami-m distribution (Nakagami, ... This paper is an improvement over beta-Nakagami distribution developed by Shittu and Adepoju (2013). Here we propose the addition of one parameter to the two parameter continuous Nakagami-m distribution (Nakagami, 1960) that was designed for modeling the fading of radio signals. The resulting distribution referred to as Exponentiated Nakagami (ENAK) distribution is a generalization of the classical Nakagami distribution. The statistical properties of the proposed distribution such as moments, moment generating function, the asymptotic behavior among others were investigated. The method of maximum likelihood is used to estimate the model parameters and the observed information matrix is derived. A real data set is used to compare the new model with the class of Nakagami distributions. Our findings showed that the Exponentiated Nakagami distribution is more flexible than beta-Nakagami distribution with better representation and less computational effort. 展开更多
关键词 NAKAGAMI exponentiated Nakagami Beta-Nakagami moments moment generating function
下载PDF
Comparisons of GCM cloud cover parameterizations with cloud-resolving model explicit simulations 被引量:4
20
作者 WANG XiaoCong LIU YiMin +1 位作者 BAO Qing WU GuoXiong 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第4期604-614,共11页
Three kinds of the widely-used cloudiness parameterizations are compared with data produced from the cloud-resolving model(CRM) simulations of the tropical cloud system. The investigated schemes include those based on... Three kinds of the widely-used cloudiness parameterizations are compared with data produced from the cloud-resolving model(CRM) simulations of the tropical cloud system. The investigated schemes include those based on relative humidity(RH), the semi-empirical scheme using cloud condensate as a predictor, and the statistical scheme based on probability distribution functions(PDFs). Results show that all three schemes are successful in reproducing the timing of cloud generation, except for the RH-based scheme, in which low-level clouds are artificially simulated during cloudless days. In contrast, the low-level clouds are well simulated in the semi-empirical and PDF-based statistical schemes, both of which are close to the CRM explicit simulations. In addition to the Gaussian PDF, two alternative PDFs are also explored to investigate the impact of different PDFs on cloud parameterizations. All the PDF-based parameterizations are found to be inaccurate for high cloud simulations, in either the magnitude or the structure. The primary reason is that the investigated PDFs are symmetrically assumed, yet the skewness factors in deep convective cloud regimes are highly significant, indicating the symmetrical assumption is not well satisfied in those regimes. Results imply the need to seek a skewed PDF in statistical schemes so that it can yield better performance in high cloud simulations. 展开更多
关键词 cloud cover relative humidity statistical cloud scheme PDFs CRM KWAJEX
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部