• Journal of Internet Computing and Services
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• v.7 no.2
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• pp.81-92
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• 2006

Recently, the number of mobile phone and PDA users has been rapidly increased. Such monitoring and control applications as geographical and traffic information systems are being used widely with wireless devices. In this paper, we introduce the mobile M/VC application framework that supports the rapid constructions of mobile monitoring and control (M/VC) applications. The mobile M/VC application framework uses the mobile Observer/Observable pattern that extends the Java's Observer/Observable for automatic interactions of server and client objects in wireless environments. It also provides the Multiplexer and Demultiplexer classes that supports the assembly feature of Observer and Observable objects. To construct an application using the framework, developers just need to create necessary objects from the Observable and MobileObserver classes and inter-connect them structurally(like the plug-and-play style) through the Multiplexer and Demultiplexer objects. Then, the state change of Observable objects is notified to the connected Observer objects and user's input with Observer objects is propagated to Observable objects. These mechanism is the main process for monitoring and control applications. Therefore, the mobile M/VC application framework can improve the productivity of mobile applications and enhance the reusability of such components as Observer and Observable objects in wireless environments.

• Industrial Engineering and Management Systems
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• v.7 no.3
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• pp.245-256
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• 2008

In order to cope with the ill-defined problem of human behavior being immanent uncertainty, several methodologies have been studied in game theoretic, social psychological and political science frameworks. As methods to arrange system elements systematically and draw out the consenting structural model concretively, ISM, FSM and DEMATEL based on graph theory etc. have been proposed. In this paper, we propose a modified structural modeling method to recognize the nature of problem. We introduce the statistical method to adjust the establishment levels in group decision situation. From this, it will become possible to obtain effectively and smoothly the structural model of group members in comparison with the traditional methods. Further we propose a procedure for achieving the consenting structural model of group members based on the structural modeling method. By applying the method to recognize the nature of ill-defined problems, it will be possible to solve the given problem effectively and rationally. In order to inspect the effectiveness of the method, we conduct a practical problem as an empirical study: "Behavior analysis of passengers for the Joban line of East Japan Railway Company after new railway service of Tsukuba Express opened".

• The Journal of Information Systems
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• v.29 no.3
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• pp.1-34
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• 2020

Purpose Due to the complexity of policy environment in modern society, it is accepted as common basics of policy design to mix up a variety of policy instruments aiming the multiple functions. However, under the current situation of written-down policy specification, not only the public officers but also the policy researchers cannot easily grasp such frameworks as policy portfolio. The purpose of this study is to develop "Policy Attributes Taxonomy" identifying and classifying the public programs to help making decisions for allocative efficiency with effectiveness-based information. Design/methodology/approach To figure out the main scheme and classification criteria of Policy Attributes Taxonomy which represents characteristics of public policies, previous theories and researches on policy components were explored. In addition, to test taxonomic feasibility of certain information system, a set of "Feasibility Standards" was drawn from "requirements for well-organized criteria" of eminent taxonomy literatures. Finally, current government classification system in the area of social service was tested to visualize the application of Taxonomy and Standards. Findings Program Taxonomy Schemes were set including "policy goals", "policy targets", "policy tools", "logical relation" and "delivery system". Each program and project could be condensed into these attributes, making their design more easily distinguishable. Policy portfolio could be readily made out by extracting certain characteristics according to this scheme. Moreover, this taxonomy could be used for rearrangement of present "Program Budget System" or estimation of "Basic Income".

• Journal of Adhesion and Interface
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• v.21 no.3
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• pp.113-122
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• 2020

Mesoporous materials are a sort of promising materials with a wide spectrum of applications due to their unique well-defined porous structures that provide high surface area and controllable pore size. Among mesoporous materials, periodic mesoporous organosilicas (PMOs) are highly emerging materials in sense of applications due to their large pore sizes and organic functionality in the frame. The organic functional groups in the frameworks of these solids allow tuning of the surface properties and modification of the bulk properties of the material. This article provides a comprehensive overview of PMOs and discusses their different functionalities, morphology and applications, such as catalysis, environmental applications, and adsorption, for which PMOs have been used after their discovery. The review article will provide fundamental understanding of PMOs and their advanced applications to readers.

• Journal of Communications and Networks
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• v.18 no.6
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• pp.926-937
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• 2016

In this paper, we study the feasibility of receiver diversity for application to downlink cellular networks, where low-energy devices are equipped with information decoding and energy harvesting receivers for simultaneous wireless information and power transfer. We compare several options that are based on selection combining and maximum ratio combining, which provide different implementation complexities. By capitalizing on the Frechet inequality, we shed light on the advantages and limitations of each scheme as a function of the transmission rate and harvested power that need to be fulfilled at the low-energy devices. Our analysis shows that no scheme outperforms the others for every system setup. It suggests, on the other hand, that the low-energy devices need to operate in an adaptive fashion, by choosing the receiver diversity scheme as a function of the imposed requirements. With the aid of stochastic geometry, we introduce mathematical frameworks for system-level analysis. We show that they constitute an important tool for system-level optimization and, in particular, for identifying the diversity scheme that optimizes wireless information and power transmission as a function of a sensible set of parameters. Monte Carlo simulations are used to validate our findings and to illustrate the trade-off that emerge in cellular networks with simultaneous wireless information and power transfer.

• Journal of KIISE
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• v.44 no.7
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• pp.726-732
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• 2017

In practical distributed sensing and prediction applications over wireless sensor networks (WSN), environmental sensing activities are highly dynamic because of noisy sensory information from moving source signals. The recent distributed online convex optimization frameworks have been developed as promising approaches for solving approximately stochastic learning problems over network of sensors in a distributed manner. Negligence of mobility consequence in the original distributed saddle point algorithm (DSPA) could strongly affect the convergence rate and stability of learning results. In this paper, we propose an integrated sliding windows mechanism in order to stabilize predictions and achieve better convergence rates in cooperative detection of a moving source signal scenario.

• The Korean Journal of Applied Statistics
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• v.33 no.3
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• pp.257-267
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• 2020

We introduce multivariate exponential smoothing models based on a vector innovations structural time series framework. The models enable us to exploit potential inter-series dependencies to improve the fit and forecasts of multivariate (vector) time series. Models are applied to forecast the exchange rates of the UK pound (UKP) and US dollar (USD) against the Korean won (KRW) observed on monthly basis; subseqently, we compare their performance with alternative models. We observe that the multivariate exponential smoothing models are superior to alternatives.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.12
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• pp.5805-5825
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• 2019

Smartphones are important platforms because of their sophisticated computation, communication, and sensing capabilities, which enable a variety of applications in the Internet of Things (IoT) systems. Moreover, advancements in hardware have enabled sensors on smartphones such as environmental and chemical sensors that make sensor data collection readily accessible for a wide range of applications. However, dynamic, opportunistic, and heterogeneous mobility patterns of smartphone users that vary throughout the day, which greatly affects the efficacy of sensor data collection. Therefore, it is necessary to consider phone users mobility patterns to design data collection schedules that can reduce the loss of sensor data. In this paper, we propose a mobility-based weighted adaptive opportunistic scheduling framework that can adaptively adjust to the dynamic, opportunistic, and heterogeneous mobility patterns of smartphone users and provide prioritized scheduling based on various application scenarios, such as velocity, region of interest, and sensor type. The performance of the proposed framework is compared with other scheduling frameworks in various heterogeneous smartphone user mobility scenarios. Simulation results show that the proposed scheduling improves the transmission rate by 8 percent and can also improve the collection of higher-priority sensor data compared with other scheduling approaches.

• Journal of the Korea Safety Management & Science
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• v.16 no.4
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• pp.101-111
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• 2014

Aviation safety is increasingly important to secure the safety of the Republic of Korea Air Force (ROKAF). A critical activity for enhancing aviation safety is to analyze an accident throughly and to identify causes that can explain it reasonably. The results of such a systematic accident investigation can be effectively used for improving information displays, task procedures, and training systems as well as for reorganizing team structure and communication control system. However, the current practice of analyzing aviation accidents in ROKAF is too superficial and simple to diagnose them systematically. Additionally, the current practice does not give a full consideration to human factors that have been identified as main causes of most of the aviation accidents. With this issue in mind, this study aims to suggest a new approach to analyzing aviation accidents related to human factors.The proposed method is developed on the basis of several models and frameworks about system safety, human error, and human-system interaction. Its application to forty-two human factors-related accidents, which have occurred in ROKAF during the last ten years, showed that the proposed method could be a useful tool for analyzing aviation accidents caused by human factors.

• Asian Journal of Innovation and Policy
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• v.3 no.1
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• pp.1-24
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• 2014

Policy planners in Asia readily covet high technology districts and regional systems of innovation such as Silicon Valley. We examine the law's role, by way of covenants not to compete (競業禁止條項) in the development of Silicon Valley by reviewing the literature from 1999 through 2013. The research suggests that in certain high-tech districts such as Silicon Valley, there are greater gains in the innovation of a region by prohibiting CNCs. While we emphasize CNC law as the main legal determinant to Silicon Valley's success, the application of trade secret law and the inevitable disclosure doctrine are also factors that can aid or restrict the mobility and knowledge spillover of a region. Even with much explored, perspectives are lacking from a regional innovation systems analysis, and more so in the context of Asian nations. To tackle these gaps, three analytical frameworks are presented that entails labor law, law and economics, and law and innovation. And from within the law and innovation framework, research is introduced in the hope that future discussions on Asian regional innovation systems consider the legal foundation of Silicon Valley.