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81.
Much attention is being paid to the services that are accessed via the Internet from mobile phones and PDAs. For such mobile Internet services, the WAP Forum issued the WAP 2.0 standard based on IETF/W3C standards. WAP 2.0 adopted the subset of eXtensible HyperText Markup Language (XHTML) and Cascading Style Sheets (CSS) standardized by World Wide Web Consortium (W3C), as its markup language. The i‐mode service in Japan was launched in February 1999, and has acquired over 40 million users, as of January 2004. The markup language adopted in the i‐mode service is called i‐mode HTML, and was designed around Compact HTML. To ease the migration from i‐mode HTML to the WAP 2.0 markup language, the functional compatibility of the languages should be assured. To this end, we proposed functions unique to i‐mode HTML to the WAP Forum. The WAP Forum accepted all of our proposals. For making the migration more cost‐effective, software tools that support the transformation of i‐mode HTML content to the WAP 2.0 equivalents must be established. There are two approaches to content transformation: software‐based and rule‐based. Since the software‐based approach has some drawbacks such as a lack of extensibility and a lack of accountability, we have taken the rule‐based approach. We focused on eXtensible Stylesheet Language Transformation (XSLT) as the content transformation technique, because XSLT has been standardized by W3C for rule‐based transformation between XML contents. To technically verify the applicability of XSLT for content transformation from i‐mode HTML to the WAP 2.0 markup language, we performed an extensive XSLT transformation experiment using existing i‐mode service contents. In this paper, we describe content transformation using XSLT, overview the content transformation system, and analyze the results of the content transformation experiment. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
82.
斜入射液晶空间光调制器的特性   总被引:4,自引:0,他引:4  
用读出光斜入射到液晶空间光调制器(LC-SLM)的读出面,是一种有效的提高空间光调制器(SLM)读出效率的方法。测量了读出光以不同角度入射到液晶空间光调制器的读出面上时,相位调制深度与写入光强的关系、衍射效率与二值光栅对比度的关系。得到随着入射角度的增加,最大相位调制深度减小,而衍射效率变化并不明显。在45°时有最大相位调制深度2.0936π和35.4%的正一级衍射效率。  相似文献   
83.
We propose a proof system for reasoning on certain specifications of secure authentication systems. For this purpose, a new logic, sequence-indexed linear-time temporal logic (SLTL), is obtained semantically from standard linear-time temporal logic (LTL) by adding a sequence modal operator that represents a sequence of symbols. By this sequence modal operator, we can appropriately express message flows between clients and servers and states of servers in temporal reasoning. A Gentzen-type sequent calculus for SLTL is introduced, and the completeness and cut-elimination theorems for it are proved. SLTL is also shown to be PSPACE-complete and embeddable into LTL.  相似文献   
84.
Virtual reality (VR) technology has become more and more mature over the last decade. Development of a virtual environment for training purpose is considered to be one of the most practical applications of the VR technology. Since the VR technology involves all kinds of sensors in exchanging information between the real world and the virtual environment, it is computationally intensive in terms of data processing at an individual sensor and information integration among all the sensors. In general, the information integration has to be well synchronized in order to meet the training needs. At the same time, real-time processing capability is also considered to be critical. Many more practical issues could be uncovered only when a virtual training environment is actually being developed. Based on this belief, this study experiments on the development of a virtual environment for training billiards players. The technical difficulties encountered and the corresponding resolutions are considered beneficial to the development of other practical virtual training environments. This paper summarizes the design and implementation details about our experimental virtual training environment for edutainment systems such as virtual billiard game, virtual air hockey game and virtual drum performance with the algorithms for the synchronization of the information from different sources.  相似文献   
85.
Collaborative capturing, interpreting, and sharing of experiences   总被引:1,自引:1,他引:0  
This paper proposes a notion of interaction corpus, a captured collection of human behaviors and interactions among humans and artifacts. Digital multimedia and ubiquitous sensor technologies create a venue to capture and store interactions that are automatically annotated. A very large-scale accumulated corpus provides an important infrastructure for a future digital society for both humans and computers to understand verbal/non-verbal mechanisms of human interactions. The interaction corpus can also be used as a well-structured stored experience, which is shared with other people for communication and creation of further experiences. Our approach employs wearable and ubiquitous sensors, such as video cameras, microphones, and tracking tags, to capture all of the events from multiple viewpoints simultaneously. We demonstrate an application of generating a video-based experience summary that is reconfigured automatically from the interaction corpus.
Yasuyuki SumiEmail:
  相似文献   
86.
In the development of a robot, the validation of that robot with the use of real machinery takes a considerable amount of time and money. In particular, it is difficult to validate a robot’s behavior in an unsafe place. The developers also have to pay attention to virtual debugging. Using a program validated in VR space makes the verification of a real machine’s behavior more efficient. In this research, we make a virtual robot walk on a road autonomously by using a program where the virtual robot tracks a line in a virtual environment.  相似文献   
87.
This paper describes the dependence of the charging characteristics on the electric field distribution on the alumina (Al/sub 2/O/sub 3/) surface as affected by the triple junction in vacuum. For HV electrical insulation design of vacuum interrupter, surface flashover in vacuum is very important problem to be solved. Attention should be paid to the fact that the insulation characteristics on the dielectric surface are strongly influenced by field emission of electrons from the triple junction and the accumulated charges on the dielectric surface. In order to clarify the charging mechanism, we measured the charging characteristics for various types of triple junctions. In particular, we focused on the influence of the electric field distribution along the solid dielectrics and near the cathode triple junction (CTJ) on the charging characteristics. The results confirmed that the electric field distribution strongly affected the 2-dimensional (2D) distribution of the surface charge on the dielectric sample. Consequently, it was found that positive charging was generated on alumina, when the incident angle of the electric line of force on the alumina surface became >60/spl deg/.  相似文献   
88.
A mixture of plastic pellets or waste plastic pieces is electrostatically separated. The mixture is charged by friction in a mixer and falls through a horizontal electric field of 4 kV/cm into three zones under the field. A mixture of two kinds of plastic pellets is separated with a purity of not less than 90%. A mixture of three kinds of pellets is separated to some extent in the zones at the extreme ends in the first separation, according to the locations of the different kinds of pellets in the triboelectric charging sequence. This mixture will be separated in successive separations following the first one into the respective pellet types. A mixer made of suitable plastic material and adapted to enhance the friction between different kinds of pellets assures easy and reliable separation. Proper mixing time, a high rotational speed of the mixer, and low humidity increase the purity of the separated pellets. Since the effect of blended additives of pellets on charging characteristics appears with good reproducibility, pellets and waste plastic pieces with such additives may likewise be successively separated into the respective plastics. © 1999 Scripta Technica, Electr Eng Jpn, 127(3): 33–40, 1999  相似文献   
89.
The SIMMER-IV computer code is a three-dimensional fluid-dynamics code coupled with a fuel-pin model and a space- and energy-dependent neutron transport kinetics model. The present study has attempted the first application of SIMMER-IV to a core disruptive accident in a large-scale sodium-cooled fast reactor. A principal point of this study was to investigate reactivity effects with fuel relocation under three-dimensional core representation including control rods. The calculation has indicated that the fuel discharge from the core was disturbed by a significant flow resistance at the entrance nozzle in the current design. Additional static neutronic calculations have been performed to compare basic neutronic characteristics between different scale cores. The static neutronic calculations have clarified that the outward fuel compaction within the inner core increased the reactivity in the large-scale core unlike the small-scale core.  相似文献   
90.
Thermal degradation of poly(diethyl vinylphosphonate) and diethyl vinylphosphonate/vinyl alcohol copolymer was investigated using thermogravimetry, infra-red spectroscopy and g.c.-mass spectrometry. For poly(diethyl vinylphosphonate), little chain scission occurred and the high stability may be attributed to POP crosslinkages between phsophonate units. With the diethyl vinylphosphonate/vinyl alcohol copolymer, the presence of hydroxyl groups in the polymer chains inhibited the formation of the POP crosslinkages. The main degradation products from the copolymer were aldehydes having the general formula HC(O)(CHCH)nCH3 and methyl ketones having the formula H3CC(O)(CHCH)nCH3 and CH3C(O)(CHCH)nCHCH2, where n = 1, 2, 3. The introduction of phosphonate unit into poly(vinyl alcohol) is less effective than that of phosphate unit in enhancement of thermal stability.  相似文献   
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