• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.4
• /
• pp.1854-1868
• /
• 2018

A wireless body-sensor network (WBSN) refers to a network-configured environment in which sensors are placed on both the inside and outside of the human body. The sensors are much smaller and the energy is more constrained when compared to traditional wireless sensor network (WSN) environments. The critical nature of the energy-constraint issue in WBSN environments has led to numerous studies on the reduction of energy consumption of WBSN sensors. The transmission-power-control (TPC) technique adjusts the transmission-power level (TPL) of sensors in the WBSN and reduces the energy consumption that occurs during communications. To elaborate, when transmission sensors and reception sensors are placed in various parts of the human body, the transmission sensors regularly send sensor data to the reception sensors. As the reception sensors receive data from the transmission sensors, real-time measurements of the received signal-strength indication (RSSI), which is the value that indicates the channel status, are taken to determine the TPL that suits the current-channel status. This TPL information is then sent back to the transmission sensors. The transmission sensors adjust their current TPL based on the TPL that they receive from the reception sensors. The initial TPC algorithm made linear or binary adjustments using only the information of the current-channel status. However, because various data in the WBSN environment can be utilized to create a more efficient TPC algorithm, many different types of TPC algorithms that combine human movements or fuse TPC with other algorithms have emerged. This paper defines and discusses the design and development process of an efficient TPC algorithm for WBSNs. We will describe the WBSN characteristics, model, and closed-loop mechanism, followed by an examination of recent TPC studies.

• Journal of Digital Convergence
• /
• v.14 no.10
• /
• pp.535-542
• /
• 2016

This study was to explore the meanings and follow-up tasks for enactment of Act on Supply and Utilization Promotion of Assistive Technology Devices for People with Disabilities and Seniors(Assistive Technology Act) in Korea. I conducted analysis about contents and establishment process of the Act. The study found meaningful effects ; it provided the basis for supporting assistive technology devices based on the social model, it led to an Implementation of the national obligations such as UN Convention on the Rights of Persons with Disabilities, it provided terms related to assistive technology. It is suggested to conduct follow-up studies and to put the efforts to strengthen additional laws for backing up the effective policy for extended support of assistive technology devices and for security of budget, for establishing regional service centers, for phasing of professional qualification, for controlling quality, for establishing an information system, and for promoting industries.

• Journal of Cadastre & Land InformatiX
• /
• v.45 no.2
• /
• pp.87-100
• /
• 2015

Currently, Korea government has strongly recommended the storm and flood insurance system to reduce the damage caused by natural disasters. The storm and flood insurance operated by private insurance company is the type of policy insurance. and is supervised by Minister of Public Safety and Security. It is the advanced disaster management system which is able to protect the public interests through unexpected natural disaster by assisting some part of the insurance premium from a central or local government. The main purpose of the present investigation is to build the insurance object GIS DB which should be necessary to calculate the premium rate in the map for storm and flood insurance, and also, to perform GIS analysis. The service model in this study is aimed to general single house, apartment and green house. The service management plan targeting the whole country has been investigated in terms of building DB and service operation.

• Journal of Communications and Networks
• /
• v.17 no.1
• /
• pp.75-83
• /
• 2015

In mobile ad-hoc networks (MANETs), nodes are mobile in nature. Collaboration between mobile nodes is more significant in MANETs, which have as their greatest challenges vulnerabilities to various security attacks and an inability to operate securely while preserving its resources and performing secure routing among nodes. Therefore, it is essential to develop an effective secure routing protocol to protect the nodes from anonymous behaviors. Currently, game theory is a tool that analyzes, formulates and solves selfishness issues. It is seldom applied to detect malicious behavior in networks. It deals, instead, with the strategic and rational behavior of each node. In our study,we used the dynamic Bayesian signaling game to analyze the strategy profile for regular and malicious nodes. This game also revealed the best actions of individual strategies for each node. Perfect Bayesian equilibrium (PBE) provides a prominent solution for signaling games to solve incomplete information by combining strategies and payoff of players that constitute equilibrium. Using PBE strategies of nodes are private information of regular and malicious nodes. Regular nodes should be cooperative during routing and update their payoff, while malicious nodes take sophisticated risks by evaluating their risk of being identified to decide when to decline. This approach minimizes the utility of malicious nodes and it motivates better cooperation between nodes by using the reputation system. Regular nodes monitor continuously to evaluate their neighbors using belief updating systems of the Bayes rule.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.9
• /
• pp.1802-1807
• /
• 2015

The cloud computing service provides physical IT resources to VM instances to users using virtual technique and the users pay cost of VM instances to service provider. The auction model based on cloud computing provides available resources of service provider to users through auction mechanism. The users bid spot instances to process their a job until its deadline time. If the bidding price of users is higher than the spot price, the user will be provided the spot instances by service provider. In this paper, we propose a new bidding strategy to minimize the total cost for job completion. Typically, the users propose bidding price as high as possible to get the spot instances and the spot price get high. we lower the spot price using proposed strategy and minimize the total cost for job completion. To evaluate the performance of our strategy, we compare the spot price and the total cost for job completion with real workload data.

• Korea and Global Affairs
• /
• v.2 no.2
• /
• pp.157-184
• /
• 2018

The study has applied the four stage "Model of State Behavior in Crisis" to trace the post 9/11 crisis foreign policy decision making process in Pakistan. It argues that ominous attacks on the United States by al-Qaeda and subsequent declaration of President Bush to fight against terrorism transformed the global and regional politico-security dimensions at t1 stage. Being a neighboring country, Pakistan's support was inevitable in the war on terror and Washington applied coercive diplomacy to win the cooperation from Islamabad. Consequently, in case of decline to accept American demands, Pakistan perceived threat to basic values/objectives of the country and simultaneous time pressure amplified the psychological stress in decision makers at t2 stage. Therefore, the decisional forum was setup at t3 stage and Pakistan decided to join the United States at t4 stage, which defused the foreign policy crisis.

• Journal of Korea Game Society
• /
• v.15 no.6
• /
• pp.171-182
• /
• 2015

Existing hydraulic terrain erosion simulations mainly focus on small scale terrain deformations. In this paper, we propose a simulation method combining hydraulic terrain erosion and thermal erosion, by which a natural large scale terrain of mountainous regions with river networks can be created. For water movement we use the pipe model of shallow water simulation, and for the easy formation of watercourse we use velocity dependent erosion, also we apply thermal erosion for the formation of V-form slopes in the vicinity of stream lines. As a result, we can obtain good natural shaped terrains for certain ranges of $K_c$(sediment capacity constant) and $K_v$(velocity dependent erosion strength) values. Also we present improved thermal erosion method, and suggest a way to avoid problems caused by large $K_c$value.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.12 no.5
• /
• pp.747-754
• /
• 2017

Chaos-based secure communication systems are alternative of standard spread-spectrum systems that enable spreading the spectrum of the information signals and encrypting information signals with simple and inexpensive chaotic circuitry. In secure communication area, like Lorenz, Chua, Rossler, Duffing etc, classical systems are widely used. Malasoma chaotic system is topologically simple but their dynamical behaviors are non-linear synchronization and secure communication applications has not seen in paper. This paper aims for introducing a new chaotic system which is able to use as alternative to classical chaotic systems into secure communication fields. In addition, this new model simulates a synchronous communication system using P-C (Pecora-Carroll) method by verifying security with chaos signal through simulation. Modelling, synchronization and secure communication applications of Malasoma are realized respectively in MATLAB-Simulink environment. Retrieved results show that this novel chaotic system is able to use in secure communication fields.

• Journal of the Korea Computer Industry Society
• /
• v.10 no.4
• /
• pp.143-150
• /
• 2009

Remote control service, monitoring, gear service of information electronic appliance, various services of security service and so on of Home network that is by link of Ubiquitous environment are offered. These services need verification process through priority test to use and are changed. If test using actuality information electronic device for test, much expenses and time may be invested. Home network test bed offers softness of research using control model and simulator, in this paper, Wish to design and embody home network test bed to do environment construction of home network and test of application service. Because use istent power line just as it is without necessity to establish circuit in addition by solution of home network testbed, expense costs to be less and establishment used easy PLC. Also, propriated Wireless sensor network that use Zigbee by solution of home network testbed. Appliance check and monitor square do by Home Auto that know embodied, and embodied by Home Gateway that interlink terminals of Home Auto and out of.

• Journal of the Korea Convergence Society
• /
• v.11 no.8
• /
• pp.39-45
• /
• 2020

Recently the terrors have been attempted in the public places of the nations such as United states, England and Japan by explosive things, toxic materials and so on. It is understood that the method in which dangerous objects are put in public places is one of the difficult types in detection. While there are the cameras recording videos for many spots in public places, it is very hard for the security personnel to monitor every videos. Nowadays the smart softwares which can analyzing videos automatically are utilized to detect abandoned objects. The method by Lin et al. shows comparatively high detection rates for abandoned objects but it is not easy to obtain the shape information because there is a tendency that the number of the pixels decreases abruptly along the time goes due to the characteristics of short-term background images. In this research a novel method is proposed to successfully extract the shape of the abandoned object by analysing the characteristics of area variation. The experiment results show that the proposed method has better performance in extracting shape information in comparison with the precedent approach.