Computer experience, learning style, and hypermedia navigation

This study focused on the extent to which prior computer-related experiences predicted linear and nonlinear navigation when using a hypermedia learning environment. Those with more years’ experience at working with computers and those with more authoring experience took more linear steps, whereas those with more data base experience and those with more hypermedia experience took fewer linear steps. Those with more years experience at working with computers, those with more programming experience, and those with more authoring experience had a lower percentage of nonlinear steps than those with more experience in those three areas. Those with more word-processing experience, more spreadsheet experience, and more hypermedia experience had a higher percentage of nonlinear steps than those with less experience in those three areas. Also, those with more hypermedia experience took less time than those with less hypermedia experience. A major implication of the study is that we can predict the extent to which a hypermedia user may engage in a hypermedia environment in a nonlinear way by knowing his or her experience in a variety of computer-related uses.     

Worm wheel mechanism with passive rollers

In this study, we developed new worm wheel mechanisms with passive rollers as their teeth and confirmed useful functions of these worm wheels with passive rollers to transmit power from worm gears with higher energy efficiency than ordinary worm wheels. By using passive rollers as their teeth, the developed worm wheels could realize high-power transmission efficiency with rolling frictional resistance instead of sliding frictional resistance. A worm wheel with conical passive rollers and one with disk-shaped passive rollers was fabricated as prototypes and examined in experiments. Smooth back-drivability of the worm wheels with passive rollers, which is difficult to realize with conventional worm wheels, was also demonstrated in the experiments. These serial experiments revealed that the developed worm wheel mechanism with passive rollers can replace conventional worm wheels with the same number of teeth and module in ordinary power transmission mechanisms with worm gearing and realize higher energy efficiency and smooth back-drivability. These features can be very useful to realize safe and soft actuators for automation systems in a human environment.     

基于宏与全局变量Floyd并行算法的性能对比

在Ubuntu操作系统上,实现多线程并行的Floyd算法。对实验数据分析表明,基于全局变量定义代价矩阵A大小的并行程序所获得的并行性能要优于基于宏参数定义矩阵A大小的并行程序的性能。这与相应的用宏参数定义矩阵A大小的串行程序性能要更优的结果相反。     

A formal model of computing with words

Classical automata are formal models of computing with values. Fuzzy automata are generalizations of classical automata where the knowledge about the system's next state is vague or uncertain. It is worth noting that like classical automata, fuzzy automata can only process strings of input symbols. Therefore, such fuzzy automata are still (abstract) devices for computing with values, although a certain vagueness or uncertainty are involved in the process of computation. We introduce a new kind of fuzzy automata whose inputs are instead strings of fuzzy subsets of the input alphabet. These new fuzzy automata may serve as formal models of computing with words. We establish an extension principle from computing with values to computing with words. This principle indicates that computing with words can be implemented with computing with values with the price of a big amount of extra computations.     

电子产品物流服务集成供应链合作利益分配机制研究

从物流服务集成商与功能型物流企业在业务上的合作关系出发,构建电子产品物流服务集成供应链合作利益分配机制,分析合作利益分配机制的运行效果以及影响因素。结果表明,最优分配系数与集成商的物流服务质量产出弹性系数呈负相关,与功能型物流企业的物流服务质量产出弹性系数呈正相关;双方投入的最优物流服务质量与产出系数呈正相关,与成本系数呈负相关;最优固定支付与产出系数呈负相关,与成本系数呈正相关。     

中国-东盟10国PDA互译系统的研发

为满足与东盟各国的交流,开发一套针对东盟10国的手持PDA翻译系统,能完成中国与东盟10国的互译(还可完成中英互译及普通话与粤语的互译),能满足与东盟交流中的互译需求.     

Organization of Parallel Query Processing in Multiprocessor Database Machines with Hierarchical Architecture

The development of database systems with hierarchical hardware architecture is currently a perspective trend in the field of parallel database machines. Hierarchical architectures have been suggested with the aim to combine advantages of shared-nothing architectures and architectures with shared memory and disks. A commonly accepted way of construction of hierarchical systems is to combine shared-memory (shared-everything) clusters in a unique system without shared resources. However, such architectures cannot ensure data accessibility under hardware failures on the processor cluster level, which limits their use in systems with high fault-tolerance requirements. In this paper, an alternative approach to construction of hierarchical systems is suggested. In accordance with this approach, the systems is constructed as an assembly of processor clusters with shared disks, with each cluster being a two-level multiprocessor structure with a standard strongly connected topology of interprocessor connections. A stream model for organization of parallel query processing in systems with the hierarchical architecture suggested is described. This model has been implemented in a prototype parallel database management system Omega designed for Russian multiprocessor computational systems MBC-100/1000. Our experiments show that the total performance of the processor clusters in the Omega system is comparable with that of the processor clusters with shared resources even in the case of great data skew. At the same time, the clusters of the Omega system are capable of ensuring a higher degree of data availability compared to the clusters with shared-memory architectures.     

面向计算机的产品创新设计新模型与新原理(II)

该文基于物元动态系统理论提出了产品虚实模型、产品潜显模型、产品正负模型等产品创新设计模型,分析了产品的同素多构性、一关系多实体性、同构多素性、虚实统一性、一显多潜性、一正多负性等性质。给出在一定的条件下,异构同功,异素同功、同潜产品同功,以及同正产品可互相转化产品、同负产品可互相转化的产品创新设计新原理。新模型和新原理有利于开发计算机辅助产品创新设计系统CAPCDS。     

A control for a rotor with a cavity containing an ideal liquid, II

For a motion perturbed with respect to uniform rotation of a body with a cavity containing an ideal liquid, two problems of optimal control with terminal functionals are considered. The model with discontinuous optimal control is studied. Numerical solutions for the problem with constraints on control of the type of inequalities are obtained.     

Effects of child restraint system features on installation errors

This study examined how child restraint system (CRS) features contribute to CRS installation errors. Sixteen convertible CRS, selected to include a wide range of features, were used in volunteer testing with 32 subjects. Subjects were recruited based on their education level (high or low) and experience with installing CRS (none or experienced). Each subject was asked to perform four child restraint installations in the right-rear passenger seat of a 2006 Pontiac G6 sedan using a crash dummy as a child surrogate. Each subject installed two CRS forward-facing (FF), one with LATCH and one with the vehicle seatbelt, and two CRS rear-facing (RF), one with LATCH and one with the seatbelt. After each installation, the experimenter evaluated 42 factors for each installation, such as choice of belt routing path, tightness of installation, and harness snugness.Analyses used linear mixed models to identify CRS installation outcomes associated with CRS features. LATCH connector type, LATCH strap adjustor type, and the presence of belt lockoffs were associated with the tightness of the CRS installation. The type of harness shoulder height adjuster was associated with the rate of achieving a snug harness. Correct tether use was associated with the tether storage method. In general, subject assessments of the ease-of-use of CRS features were not highly correlated with the quality of their installation, suggesting a need for feedback with incorrect installations.The data from this study provide quantitative assessments of some CRS features that were associated with reductions in CRS installation errors. These results provide child restraint designers with design guidelines for developing easier-to-use products. Research on providing effective feedback during the child restraint installation process is recommended.     

具有动态领导节点的多智能体系统一致性分析

具有领导节点的一致性问题是多智能体协调控制重要研究内容。目前其研究结论主要集中在系统通信拓扑关系固定不变这一前提下,对于系统通信拓扑关系为动态变化时具有领导节点的一致性问题尚未得到完全解决。对系统通信拓扑关系为有向、时变情况下的具有领导节点的多智能体系统一致性问题进行研究。分析并给出了在领导节点为常值和时变两种情况下多智能体系统达到一致的条件。并通过矩阵论和图论相关知识给出了详细证明。最后通过仿真实例验证了结论的正确性。     

Bonded thick film SOI with pre-etched cavities

We have studied direct bonding and thinning of pre-etched silicon wafers. Silicon-on-insulator (SOI) substrates with pre-etched cavities provide freedom to MEMS design and enable manufacturing of advanced sensor structures (sensor structures that would be difficult or impossible with conventional substrates). Cavities with different shapes and sizes were etched on to the handle wafers. The etched handle wafers were bonded to unpatterned cap wafers in air or in vacuum. The bonding quality was evaluated with scanning acoustic microscopy and with HF-etching test. After bonding, the cap wafers were thinned down with grinding and polishing. The thickness variation of silicon diaphragm over the cavities was evaluated with cross-sectional SEM. The deflection of the Si film was measured with surface profilometry. To decrease the deflection and the thickness variation of the film, different support structures were placed inside the cavities.The bonding experiments carried out with patterned wafers showed that vacuum bonding results in slightly higher bonding energy than bonding in air. With large cavity fraction (80% of total wafer area), the air bonded samples had large void on the bonded interface. With smaller cavity fractions or with vacuum bonded samples, no such voids were found. Thinning studies showed that the thickness variation of the silicon diaphragm increases with increasing cavity dimensions and with decreasing SOI layer thickness. Thickness variation can be reduced with support structures under the Si membrane.     

分布参数控制系统的镇定问题

本文讨论了具有两个观测器的弹性振动系统的镇定问题和具有两个反馈信号的带控制器的弹性振动系统的镇定问题。带两个观测器的弹性振动闭环系统较具有一个观测器的弹性振动闭环系统有更好的稳定性能。具有两个反馈信号的带控制器的弹性振动闭环系统较具有一个反馈信号的带控制器的弹性振动闭环系统有更好的稳定性能。     

Control 5.0: From Newton to Merton in Popper's Cyber-Social-Physical Spaces

The future of control in cyberspace of parallel worlds is discussed. It argues for the coming age of Control 5.0, the control technology for the new IT capable of dealing with artificial worlds with VR, AR, AI and robotics. The discipline of automation needs a new interpretation of its core knowledge and skill set of modeling, analysis, and control for cyber-socialphysical systems, and a paradigm shift from Newtonian Systems with Newton's Laws or Big Laws with Small Data to Mertonian Systems with Merton's Laws or Small Laws with Big Data.      

A unified setting for decoupling with preview and fixed-lag smoothing in the geometric context

Exact decoupling with preview, perfect tracking of previewed references, unknown-input state observation with fixed lag, and left inversion with fixed lag are considered from a unifying perspective where exact decoupling with preview is the basic problem. Necessary and sufficient constructive conditions for decoupling with finite preview are proved in the geometric framework. Structural and stabilizability conditions are considered separately and the use of self-bounded controlled invariant subspaces allows the dynamic compensator with the minimal unassignable dynamics to be straightforwardly derived. A steering along zeros technique is devised to guarantee decoupling with stability also in the presence of unstable unassignable dynamics of the minimal self-bounded controlled invariant.     

基于进化MCMC的DBN学习算法

提出利用进化MCMC算法进行动态贝叶斯网络(DBN)学习的方法。在数据缺省情况下利用EM算法进行贝叶斯网络参数学习,结构学习部分生成多条备选的贝叶斯网络染色体,对染色体进行变异操作和交叉操作,在遗传操作中根据温度参数和贝叶斯网络及贝叶斯信息准则来构造MCMC函数,并利用MCMC函数进行贝叶斯网络学习。每一代进化后,将贝叶斯信息评分最大的贝叶斯网络作为结构学习的结果。实验结果验证了该方法性能的稳定性。     

Retraction and Generalized Extension of Computing With Words

Fuzzy automata, whose input alphabet is a set of numbers or symbols, are a formal model of computing with values. Motivated by Zadeh's paradigm of computing with words rather than numbers, Ying proposed a kind of fuzzy automata, whose input alphabet consists of all fuzzy subsets of a set of symbols, as a formal model of computing with all words. In this paper, we introduce a somewhat general formal model of computing with (some special) words. The new features of the model are that the input alphabet only comprises some (not necessarily all) fuzzy subsets of a set of symbols and the fuzzy transition function can be specified arbitrarily. By employing the methodology of fuzzy control, we establish a retraction principle from computing with words to computing with values for handling crisp inputs and a generalized extension principle from computing with words to computing with all words for handling fuzzy inputs. These principles show that computing with values and computing with all words can be respectively implemented by computing with words. Some algebraic properties of retractions and generalized extensions are addressed as well.     

Probabilistic characteristics of paramacrosystems

Consideration is given to macrosystems called paramacrosystems with different elements, with stochastic behavior, and states of finite capacity. Thus is fulfilled the interval between two classical capacity characteristics of states: Fermi, with one element, and Einstein, with unlimited number of elements in each state. Using the apparatus of generating functions, we obtained expressions for probabilistic characteristics (functions of probability distribution and “physical” entropies) for four classes of paramacrosystems with corresponding combinations of distinguishable and indistinguishable elements and states with finite capacities.     

基于压电陶瓷的不同服役年限木构件损伤监测

基于压电陶瓷的主动传感技术对不同服役年限的木构件进行损伤评估。取服役年限为0年、3年、40年的木构件制成三个尺寸相同的立方体试件,在每个试件的六个面上分别粘贴压电陶瓷片(PZT),用于信号的发射及接收。分别对不同服役年限试件传感器测量的信号进行了小波包和功率谱分析,发现应力波沿木材纵向传播时相较于服役年限短的试件,长年限试件的信号的幅值更大,沿木材径向及弦向传播时随木材服役年限的增加信号的幅值随之减小。结果表明,文中提出的方法能有效的识别不同服役年限的木构件,可为实际工程中不同服役年限木结构古建筑健康监测提供参考。     

促花措施对日光温室甜樱桃幼树成花及坐果的影响

日光温室中甜樱桃采用刻芽、环剥、绞缢、PP333等促花措施处理，促花效果以环剥后不包伤口、绞缢、短梢停长期低浓度PP333喷布和中长梢停长期高浓度PP333蘸尖效果较好。日光温室中甜樱桃可多次分化花芽，中后期形成的花芽坐果率明显高于前期。