Naotake KAMIURA Shoji KOBASHI Manabu NII Takayuki YUMOTO Ichiro YAMAMOTO
In this paper, we present a method of analyzing relationships between items in specific health examination data, as one of the basic researches to address increases of lifestyle-related diseases. We use self-organizing maps, and pick up the data from the examination dataset according to the condition specified by some item values. We then focus on twelve items such as hemoglobin A1c (HbA1c), aspartate transaminase (AST), alanine transaminase (ALT), gamma-glutamyl transpeptidase (γ-GTP), and triglyceride (TG). We generate training data presented to a map by calculating the difference between item values associated with successive two years and normalizing the values of this calculation. We label neurons in the map on condition that one of the item values of training data is employed as a parameter. We finally examine the relationships between items by comparing results of labeling (clusters formed in the map) to each other. From experimental results, we separately reveal the relationships among HbA1c, AST, ALT, γ-GTP and TG in the unfavorable case of HbA1c value increasing and those in the favorable case of HbA1c value decreasing.
Kenichiro YAMAMOTO Osamu TAKYU Keiichiro SHIRAI Yasushi FUWA
Recently, broadband wireless communication has been significantly enhanced; thus, frequency spectrum scarcity has become an extremely serious problem. Spatial frequency reuse based on spectrum databases has attracted significant attention. The spectrum database collects wireless environment information, such as the radio signal strength indicator (RSSI), estimates the propagation coefficient for the propagation loss and shadow effect, and finds a vacant area where the secondary system uses the frequency spectrum without harmful interference to the primary system. Wireless sensor networks are required to collect the RSSI from a radio environmental monitor. However, a large number of RSSI values should be gathered because numerous sensors are spread over the wireless environment. In this study, a data compression technique based on spatial features, such as buildings and houses, is proposed. Using computer simulation and experimental evaluation, we confirm that the proposed compression method successfully reduces the size of the RSSI and restores the original RSSI in the recovery process.
Naoki KASAI Ichiro YAMAMOTO Koji URABE Kuniaki KOYAMA
Effects of field edge steps on characteristics of MOSFETs with tungsten polycide stacked gate electrodes patterned by KrF excimer laser lithography was studied through an electrical gate length measurement technique. Sheet resistance of the gate electrodes on the field oxide, on the active region and across the field edge steps was determined from the relationship between gate conductance and designed gate linewidth. The sheet resistance of the gate electrode across the field edge steps was larger than that on the flat regions. Effects of field edge steps on gate linewidth variation were evaluated by SEM observations and electrical measurements. Distribution of gate linewidth in a wafer was measured by the MOSFET test structures with the linewidth down to sub-quarter micron. Gate linewidth variation near the field edge steps was found to influence the short channel MOSFET characteristics.
Shinichiro YAMAMOTO Kenichi HATAKEYAMA Takanori TSUTAOKA
This paper proposes reflection and transmission control panels using artificially designed materials. As the artificially designed material, finite- and infinite-length metal wire array sheets are used here. Laminated structures consisting of the metal wire array sheets and dielectric material are proposed. Reflection and transmission characteristics of these structures can be controlled by changing the metal wire parameters such as wire length, spacing gaps between the wires, and the dielectric material's thickness and relative permittivity. The reflection and transmission characteristics of the laminated structures are evaluated by measurements in free space and by transmission line theory.
Shuichiro YAMAMOTO Haruhiko KAIYA Karl COX Steven BLEISTEIN
Research has been actively proposed into how to specify requirements in the upper stream of software development. For example, the main research issues regarding Structured Analysis and Object Oriented Analysis methodologies include requirements elicitation, modeling, and validation of specifications to give a starting point for software development. At the same time, another area of research has emerged that recognizes the importance of guaranteeing requirements quality by goals. As the impact of IT penetrates to mobile devices, information appliances and automobiles, goal oriented requirements engineering (GORE) approaches for performance and safety in embedded systems have been proposed. Non-Functional Requirements (NFRs) such as business strategy, security and privacy, are now being formalized by Requirements Engineering (RE) technologies, because enterprise business is now heavily influenced by IT, for example in e-Business. As IT is fast becoming ubiquitous in society, the importance of Goal Orientation will increase as socio-technology enables visualization of the role of software in social systems. In this paper, we discuss the current states and trends of GORE from the viewpoints of both academia and industry.
Masakazu MORIMOTO Naotake KAMIURA Yutaka HATA Ichiro YAMAMOTO
To promote effective guidance by health checkup results, this paper predict a likelihood of developing lifestyle-related diseases from health check data. In this paper, we focus on the fluctuation of hemoglobin A1c (HbA1c) value, which deeply connected with diabetes onset. Here we predict incensement of HbA1c value and examine which kind of health checkup item has important role for HbA1c fluctuation. Our experimental results show that, when we classify the subjects according to their gender and triglyceride (TG) fluctuation value, we will effectively evaluate the risk of diabetes onset for each class.
Tadahiko SUGIBAYASHI Isao NARITAKE Hiroshi TAKADA Ken INOUE Ichiro YAMAMOTO Tatsuya MATANO Mamoru FUJITA Yoshiharu AIMOTO Toshio TAKESHIMA Satoshi UTSUGI
A distributive serial multi-bit parallel test scheme for large capacity DRAMs has been developed. The scheme, distributively and serially, extracts and compares the data from cells on a main word-line. This test scheme features a high parallel test bit number, little restriction on test patterns, and, with regard to cells and sense-amplifiers, the same operational margin as normal mode. In an experimental 256-Mb DRAM, the scheme successfully has achieved a 512-bit parallel test.
Yutaka MATSUNO Toshinori TAKAI Shuichiro YAMAMOTO
Assurance cases are documents for arguing that systems satisfy required properties such as safety and security in the given environment based on sufficient evidence. As systems become complex and networked, the importance of assurance cases has become significant. However, we observe that creating assurance cases has some essential difficulties, and unfortunately it seems that assurance cases have not been widely used in industries. For this problem, we have been developing assurance cases creation methods and opening workshops based on the creation methods. This paper presents an assurance cases creation method called “D-Case Steps” which is based on d* framework[1], an agent-based assurance case method, and reports the results of workshops. The results indicate that our workshops have been improved and our activities on assurance cases facilitates use of them in Japan. This paper is an extended version of [2]. We add detailed background and related works, workshops results and evaluation, and lessons learned from our a decade experiences.
Jun SATO Tsutomu KIMURA Masaharu IMAI Frank de SCHEPPER Kazuo YAMAZAKI Masashi NAGASE Shin-ichiro YAMAMOTO
This letter describes the architecture and ASIC implementation of the FSP-3 (Flexible Servo motor control Processor-3) chip. The FSP-3 is a special purpose 32 bit microprocessor dedicated to the Flexible Servo Control System (FSC), which is able to manipulate various kinds of servo motors efficiently. FSP-3 chip is one of the largest scale system ASICs entirely designed in Japanese universities.
Katsuhisa MARUYAMA Shinichiro YAMAMOTO
Recent IDEs have become more extensible tool platforms but do not concern themselves with how other tools running on them collaborate with each other. They compel developers to use proprietary representations or the classical abstract syntax tree (AST) to build source code tools. Although these representations contain sufficient information, they are neither portable nor extensible. This paper proposes a tool platform that manages commonly used, fined-grained, information about Java source code by using an XML representation. Our representation is suitable for developing tools which browse and manipulate actual source code, since the original code is annotated with tags based on its structure and retained within the tags. Additionally, it exposes information resulting from global semantic analysis, which is never provided by the typical AST. Our proposed platform allows the developers to extend the representation for the purpose of sharing or exchanging various kinds of information about the source code, and also enables them to build new tools by using existing XML utilities.
Shinnichiro YAMAMOTO Kennichi HATAKEYAMA Kenji YAMAUCHI Takeshi YAMADA
A new shielding evaluation setup for conductive O-rings is proposed. This setup consists of the holder with a groove to fix the O-ring position. There are two ways to apply O-rings in narrow gaps, cylinder-fixing and plane-fixing. With this holder shielding effects of the O-rings can be evaluated from 10 kHz to 1 GHz for both fixing types.
Eikazu NIWANO Junko HASHIMOTO Shoichi SENDA Shuichiro YAMAMOTO Masayuki HATANAKA
The demand for multi-application smart card platform has been increasing in various business sectors recently. When it comes to the actual implementation of the platform, however, network-based dynamic downloading in a Card Issuer-Service Provider separated environment has not made much progress. This paper introduces the smart card information sharing platform that uses licensing/policy/profile management and PKI-based technologies to enable multiple CIs and multiple SPs to reflect their own business policy flexibly via network. It makes the paradigm shift from card-oriented scheme to service-oriented scheme. By through world's first implementation of the scheme and some experiments including deployment, we confirmed that this technology is well-accepted and applicable to various business sectors and it can be of practical use.
Shinichiro YAMAMOTO Daisuke ISHIHARA Kenichi HATAKEYAMA
This paper proposes a method of designing EM absorber panels under oblique incident waves. TM and TE wave reflection characteristics of the absorber panel show its anisotropy under oblique incidence. By using the wire array sheet proposed this paper, TM and TE reflection coefficients in oblique incidence can be matched at almost the same frequency range.
Shuichiro YAMAMOTO Hiroaki KUROKI
Object-oriented analysis methods can be grouped into data-driven and behavior-driven approaches. With data-driven approaches, object models are developed based on a list of objects and their inter-relationships, which describe a static view of the real world. With behavior-oriented approaches, a system usage scenario is analyzed before developing the object models. Although qualitative comparisons of these two types of methods have been made, there was no statistical study has evaluated them based on controlled experiments. This paper proposes the patterned object-oriented method, POOM, which is a behavior-oriented approach, and compares it to OMT, a data-driven approach, using small team experiments. The effectiveness of POOM is shown in terms of productivity and homogeneity.
Kunihiro NODA Takashi KOBAYASHI Shinichiro YAMAMOTO Motoshi SAEKI Kiyoshi AGUSA
Program comprehension using dynamic information is one of key tasks of software maintenance. Software visualization with sequence diagrams is a promising technique to help developer comprehend the behavior of object-oriented systems effectively. There are many tools that can support automatic generation of a sequence diagram from execution traces. However it is still difficult to understand the behavior because the size of automatically generated sequence diagrams from the massive amounts of execution traces tends to be beyond developer's capacity. In this paper, we propose an execution trace slicing and visualization method. Our proposed method is capable of slice calculation based on a behavior model which can treat dependencies based on static and dynamic analysis and supports for various programs including exceptions and multi-threading. We also introduce our tool that perform our proposed slice calculation on the Eclipse platform. We show the applicability of our proposed method by applying the tool to two Java programs as case studies. As a result, we confirm effectiveness of our proposed method for understanding the behavior of object-oriented systems.
Kenji TAKAHASHI Shuichiro YAMAMOTO
We study the correspondence between problem descriptions and requirements specification documents derived from them. Based on the results of this investigation, a model that integrates the problem space and the requirements specification space is developed. This integration is based on a semantic network representation. We also propose a model of the requirements elicitation process that is consistent with our empirical studies of traceability in requirements documents. In this process, analysts derived requirements specifications from incomplete and ambiguous problem descriptions given by customers, identify missing information, completed it, and then decide the system boundaries that define which part of the problem descriptions to implement as the target system. The model can be used to complete problem descriptions given by customers and determine the system boundaries.
Takashi HATASHIMA Toshihiro MOTODA Shuichiro YAMAMOTO
We describe an index for estimating the level of interest in Web pages. This "time-based interest" (TBI) index combinates an equation reflecting page accesses and an equation reflecting the decrease in interest over time. These equations work simultaneously by using a parameter that is based on the time since the last access. We experimentally estimated the decrease ratio of the TBI index and evaluated the characteristics of the TBI equation. We found that the index follows Zipf's distribution, indicating that reflects the change in popularity. We also introduce an access-log analysis system called CyberRanking that includes TBI analysis. CyberRanking analyzes the access logs of Web servers and presents the results in 2-D or 3-D graph on a Web browser.
Shinichiro YAMAMOTO Tohru IWAI Kenichi HATAKEYAMA
In this paper, an evaluation method for electromagnetic wave absorber with anisotropic reflection properties is discussed. Anisotropic absorber panels have an axis of anisotropy (principal axis). In order to specify the principal axis, the evaluation method based on the diagonalization of reflection coefficient matrix is used. Also, the permittivity of absorber materials is considered.
The traceability of data flow diagrams against structure charts is very important for large software development. Specifying if there is a relationship between a data flow diagram and a structure chart is a time consuming task. Existing CASE tools provide a way to maintain traceability. If we can extract the input-output relationship of a system from a structure chart, the corresponding data flow diagram can be automatically generated from the relationship. For example, Benedusi et al. proposed a reverse engineering methodology to reconstruct a data flow diagram from existing code. The methodology develops a hierarchical data flow diagram from dependency relationships between the program variables. The methodology, however, transforms each module in structure charts into a process in data flow diagrams. The reconstructed diagrams may have different processes with the same name. This paper proposes a transformation algorithm that solves these problems. It analyzes the structure charts and extracts the input and ouput relationships, then determines how the set of outputs depends on the set of inputs for the data flow diagram process. After that, it produces a data flow diagram based on the include operation between the sets of output items. The major characteristics of the algorithm are that it is simple, because it only uses the basic operations of sets, it generates data flow diagrams with deterministic steps, and it can generate minimal data flow diagrams. This process will reduce the cost of traceability between data flow diagrams and structure charts.