新高考选考科目计分机制的主要问题及建议

新高考改革赋予了考生选择高考科目、多次参加考试的权利,有效缓解了"唯分数论"和"文理过度偏科"等现象。然而,选考科目计分机制却出现了与政策设计初衷相矛盾的现象,主要表现为两个方面:一是与"根据报考高校要求和自身特长"选考的政策设计相矛盾;二是与"为有需要的学生提供同一科目参加两次考试的机会"政策设计相矛盾。应在新高考试点地区完善相关政策,解决计分方式的"失灵";在未开展试点地区,应加强研究,使用国际通行的计分与分数校准方式,实现选考科目计分的科学与公平。

STAD型合作学习在初中信息技术课堂教学中的应用

随着课程改革的推进，合作学习作为一种重要的学习方式，已经在中小学课堂教学中得到广泛运用，但合作学习并非是几个学生简单的组合，它需要教师的精心组织、学生的积极主动参与才能收到预期的效果。本文主要简述了STAD型合作学习模式的内涵，重点阐述它在信息技术课堂教学中应用的操作流程和应用策略，并对其评价机制和注意的问题作一些探讨。

我国信用卡业务风险的宏微观分析

近些年来,随着国民经济的发展我国的信用卡业务飞速发展,有资料显示,从2003年到2005年的时间里,国内信用卡发行扩大了600%,这是一种令人欣喜的增长速度。然而在卡量暴增的同时,风险也正在积聚。本文对这些风险进行了分析,并尝试找出有效的解决方法以帮助我国降低出现类似于2003年韩国信用卡危机的可能性。

Research and Design of Sleeve Detach and Reunion Drive Mechanism of Screw Melt Extruder Equipment

The design of sleeve detach and reunion drive device of screw melt ex- truder equipment was optimized, based on the present installation of hygraulic drive device to achieve the mechanical opening and closing of the sleeve, the dynamic model of the sleeve detach and reunion drive was theoretically measured, and it was verified that the device is simple to operate and convenient to maintain, thus it has great social values.

Customer Requirements Mapping Method Based on Association Rule Mining for Mass Customization

Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD pro-cess and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method.

A CAD EXPERT SYSTEM OF AIRCRAFT MANUFACTURING COORDINATION

讨论了工程CAD专家系统特点，提出其一般结构。为了解决如飞机制造协调等复杂工程问题，实现一种层次分布式CAD专家系统（HDES）结构。HDES由元级、任务级两个水平的分布式专家系统组成：任务级专家系统（T－ES）主要用于应用设计，它们在其自己的设计领域中执行；元级专家系统（M－ES）则处理合作。介绍了层次－框架－规则的专家系统组织表示方法。

A New Multi-Resource Allocation Mechanism： A Tradeoff between Fairness and Efficiency in Cloud Computing

This paper addresses multi-resource fair allocation: a fundamental research topic in cloud computing. To improve resource utilization under well-studied fairness constraints, we propose a new allocation mechanism called Dominant Resource with Bottlenecked Fairness(DRBF), which generalizes Bottleneck-aware Allocation(BAA) to the settings of Dominant Resource Fairness(DRF). We classify users into different queues by their dominant resources. The goals are to ensure that users in the same queue receive allocations in proportion to their fair shares while users in different queues receive allocations that maximize resource utilization subject to well-studied fairness properties such as those in DRF. Under DRBF, no user 1) is worse off sharing resources than dividing resources equally among all users; 2) prefers the allocation of another user; 3) can improve their own allocation without reducing other users' allocations; and(4) can benefit by misreporting their resource demands. Experiments demonstrate that the proposed allocation policy performs better in terms of high resource utilization than does DRF.

Fog Computing Dynamic Load Balancing Mechanism Based on Graph Repartitioning

Because of cloud computing's high degree of polymerization calculation mode, it can't give full play to the resources of the edge device such as computing, storage, etc. Fog computing can improve the resource utilization efficiency of the edge device, and solve the problem about service computing of the delay-sensitive applications. This paper researches on the framework of the fog computing, and adopts Cloud Atomization Technology to turn physical nodes in different levels into virtual machine nodes. On this basis, this paper uses the graph partitioning theory to build the fog computing's load balancing algorithm based on dynamic graph partitioning. The simulation results show that the framework of the fog computing after Cloud Atomization can build the system network flexibly, and dynamic load balancing mechanism can effectively configure system resources as well as reducing the consumption of node migration brought by system changes.

Attack Vulnerability of Network with Duplication-Divergence Mechanism

We study the attack vulnerability of network with duplication-divergence mechanism. Numerical results have shown that the duplication-divergence network with larger retention probability a is more robust against target attack relatively. Furthermore, duplication-divergence network is broken down more quickly than its counterpart BA network under target attack. Such result is consistent with the fact of WWW and Internet networks under target attack. So duplication-divergence model is a more realistic one for us to investigate the characteristics of the world wide web in future. We also observe that the exponent γ of degree distribution and average degree are important parameters of networks, reflecting the performance of networks under target attack. Our results are helpful to the research on the security of network.

The Design of Small Micro-UAV Formation of ＂Sub-mother＂ type

This paper aims to provide a design about a kind of low-cost ＂sub-mother＂ UAV small formation by using the low-cost micro-UAV as the platform. Combined with the current international situation in the UAV formation research, the modeling is based on the distributed control method and the behavior-based strategy. In this paper, some research to a few key issues has been carried out.

A Multi-Level Authorization Based Tenant Separation Mechanism in Cloud Computing Environment

Separation issue is one of the most important problems about cloud computing security. Tenants should be separated from each other based on cloud infrastructure and different users from one tenant should be separated from each other with the constraint of security policies. Learning from the notion of trusted cloud computing and trustworthiness in cloud, in this paper, a multi-level authorization separation model is formally described, and a series of rules are proposed to summarize the separation property of this model. The correctness of the rules is proved. Furthermore, based on this model, a tenant separation mechanism is deployed in a real world mixed-critical information system. Performance benchmarks have shown the availability and efficiency of this mechanism.

Design and Implementation of Distributed Numerical Control in Flexible Manufacturing System

To monitor, control and manage the work process of computer numerical control machine tools in a flexible manufacturing system (FMS) effectively, the distributed numerical coutrol (distributed-NC) software should be innovated with the characteristics of modularization and reconfiguration. In this paper, firstly, distributed-NC functions in the FMS environment are described. Then, we present a design and development method of the real time distributed-NC that is on the basis of the re-coufigurable software and hardware platform and with an object-oriented model concept. Finally, to verify the proposed method, the distributed-NC software has been implemented in VC++ 6.0 and has been tested in connection with the different physical flexible manufacturing shops.

STUDY ON PRODUCTION SYSTEM OPERATION REGULARITY OF FULLY MECHANIZED SUBLEVEL CAVING MINING AND SEQUENTIAL OPERATION

According to a lot of practical data in Liujialiang Mine and reliability theory and result of computer simulation, operation regularity of fully mechanized sublevel caving mining production system in the condition of gently inclined complicated geological structure and production shortcomings are found out and reliability of system and output of the working face are predicted finally.

Actual implementation of spectrum-sharing systems in rayleigh fading channels~

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.

Statistical analysis on 2213 inpatients with traffic injuries from January 2003 to September 2005 in Ningbo city

To analyze the epidemiological conditions and characteristics of inpatients with traffic trauma in order to provide objective data for basic research and clinical application of traffic trauma. Methods： The data of 2213 inpatients with traffic trauma admitted to Lihuili Hospital, Ningbo Medical Centre, Ningbo, China, from January 2003 to September 2005 were studied retrospectively. According to the transportation ways, the patients were divided into four groups： pedestrians, bicyclists, motorcyclists, and automobilists. And the data of injured regions, combined injuries and causes of death were analyzed statistically. Results： Among the 2213 patients, there were 550 pedestrians （ 23. 5 %）, 521 bicyclists （24. 9%）, 738 motorcyclists （33.3%）, and 404 automobilists （18.3%）, Male patients were more than female ones, with the ratio of male to female of 2.8：1. Single region injury was found in 1663 patients （75.15%） and multiple injuries in 550 patients （24.85 % ）. In total, 2849 regions were injured. Fracture of extremities （53.3%） occurred most often, craniocerebral tranma （19. 4% ） next, then followed in turn by fracture visceral injury （6.56%）, spine （5.37 % ）, fracture of ribs （4.88 % ）, and pelvic fracture （4.18%）. The percentage of multiple injuries （33.2%） was highest and the percentage of thoracoabdominal injury （18.0%） was higher in motorcyclists. The percentages of craniocerebral trauma in pedestrians and bicyclists were 27.8 % and 28.2 %, respectively. The incidence of fracture of extremities in motorcyclists reached 73.8%, but with the lowest case-fatality ratio of 1.4%. The incidence of traffic accidents caused by motorcyclists themselves （32.8%） was highest. A total of 56 patients died, with the case-fatality ratio of 2.53%. Among the deaths, 47 died from craniocerebral injury, 6 from multiple fractures combined with hemorrhagic shock, 2 from combined injury in the thoraco-abdominal region, and 1 from cervical cord injury. Concinsions： Nowadays, the patients with traffic trauma are mainly pedestrians, bicyclists and motorcyclists, and they suffer generally from fracture of extremities and craniocerebral injury. The main cause of death is craniocerebral injury. Another characteristic of traffic trauma is that the ratio of multiple injuries is higher.

Biomechanical effect of vertebroplasty on the adjacent intervertebral levels using a three.dimensional finite element analysis

Objective： To investigate the biomechanical effect of different volume, distribution and leakage to adjacent disc of bone cement on the adjacent vertebral body by threedimensional osteoporosis finite element model of lumbar. Methods ： L4-L5 motion segment data of the cadaver of an old man who had no abnormal findings on roentgenogrmns were obtained from computed tomography （CT） scans. Three-dimensional model of L4-L5 established with Mimics software, and finite element model of L4-L5 functional spinal unit （FSU） was established by Ansys 7. 0 software. The effect of different loading conditions and distribution of bone cement after vertebroplasty on the adjacent vertebral body was investigated. Results： This study presented a validated finite element model of L4-L5 FSU with a simulated vertebroplasty augmentation to predict stresses and strains of adjacent untreated vertebral bodies. The findings from this FSU study suggested the endplate and disc stress of the adjacent vertebral body was not influenced by filling volume of bone cement but unipedicle injection and leakage to the disc of bone cement could concentrate the stress of adjacent endplate. Conclusions： Asymmetric distributions and leakage of cement into intervertebral disc can improve the stress of endplate in adjacent vertebral body. These results suggest that optimal biomechaulcal configuration should have symmetric placement and avoid leakage of cement in operation.

Chemical comparison of Semen Euphorbiae and Semen Euphorbiae Pulveratum by UPLC-Q-TOF/MS coupled with multivariate statistical techniques

In the present study,we aimed to assess the chemical composition changes of Semen Euphorbiae(SE)and Semen Euphorbiae Pulveratum(SEP)by UPLC-Q-TOF/MS and multivariate statistical methods.The UPLC-Q-TOF/MS method and SIMCA-P software were used to analyze the changes of chemical components of SE and SEP based on PCA and PLS-DA multivariate statistical methods.A"component-target-disease"network model was constructed by Intelligent Platform for Life Sciences of traditional Chinese medicine(TCM)to predict potential related diseases.The differences of chemical composition were significant between SE and SEP.Under positive ion mode,the amounts of Euphorbia factor L2,L3,L7a,L8,L9 and lathyrol were obviously decreased after processing.Under negative ion mode,the amounts of aesculetin,bisaesculetin,ingenol and cetylic acid were increased obviously,while Euphorbia factor L1,L4 and L5 were decreased obviously after processing,and the components of euphobiasteroid,aesculetin,lathyrol and linoleic acid among the 14 differentiated compounds were closely related to the SE-related diseases through the"component-target-disease"network model.UPLC-Q-TOF/MS technology in combination with multivariate statistical methods had certain advantages in studying the complex changes of chemical composition before and after manufacturing pulveratum of SE.It provided a basis for clarifying the toxicity-attenuated mechanisms of SE manufacturing pulveratum,and laid the foundation for its further development and utilization.