• Journal of electromagnetic engineering and science
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• v.16 no.2
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• pp.87-99
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• 2016

This paper describes an implementation method and the results of numerical mobile phone models representing real phone models that have been released on the Korean market since 2002. The aim is to estimate the electromagnetic absorption in the human brain for case-control studies to investigate health risks related to mobile phone use. Specific absorption rate (SAR) compliance test reports about commercial phone models were collected and classified in terms of elements such as the external body shape, the antenna, and the frequency band. The design criteria of a numerical phone model representing each type of phone group are as follows. The outer dimensions of the phone body are equal to the average dimensions of all commercial models with the same shape. The distance and direction of the maximum SAR from the earpiece and the area above -3 dB of the maximum SAR are fitted to achieve the average obtained by measuring the SAR distributions of the corresponding commercial models in a flat phantom. Spatial peak 1-g SAR values in the cheek and tilt positions against the specific anthropomorphic mannequin phantom agree with average data on all of the same type of commercial models. Second criterion was applied to only a few types of models because not many commercial models were available. The results show that, with the exception of one model, the implemented numerical phone models meet criteria within 30%.

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

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.978-979
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• 2006

Recently, Peoples are exposed the ELF(Extremely Low Frequency) magnetic fields in the vicinity of underground transmission lines, and there are the generally accepted opinion that the magnetic fields affect the human body and there are possibility of the disease. Also in relation to this problem, technical solution methods and research are advanced for reducing the magnetic fields. In this paper, to practically understand the magnetic fields underground transmission lines, We analyze the electromagnetic field distribution in the underground transmission lines by means of FEM(Finite Element Methods) and present that improvement of the effective shielding methods by applying cable arrangements and shielding materials, eddy current problem to the underground transmission lines by means of the numerical analysis Tool.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.4
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• pp.831-837
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• 2017

The development of various electronic media such as the Internet and smart phones, each kinds of media informations has been accompanied by the fact that various types of media information are provided from one media, and on the other hand, various dysfunctions including smart phone addiction are also caused by a very large social problem. Especially, one of the biggest dysfunctions is the social crime problem such as sex crime caused by increased sexual desire according to watch the phonography, and even if it is not a social crime, watching the phonography has influenced bad mental and physical on human body. In this paper, we try to analyze what kind of change occurs in the voice in order to investigate what kind of bad influence it has on the human body after watching the phonography. In other words, the voice in the human body is the place where the human body signal is most expressed with the face. Therefore, the purpose of this study is to investigate the effects on the organs of the human body by comparing the change of voice before and after watching phonography. Experimental results showed that the stress hormone was increased by the inability to resolve sexual desire after watching the phonography, which resulted in an increase in the bandwidth of the 3rd formant frequency.

• Journal of Communications and Networks
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• v.13 no.2
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• pp.142-148
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• 2011

Because currently available wireless technologies are not appropriate for wireless body area networks (WBANs), the IEEE 802.15.6 standard was introduced by the IEEE 802.15.6 Task Group to satisfy all the requirements for a monitoring system that operates on, in, or around the human body. In this work, we develop an analytical model for evaluating the performance of an IEEE 802.15.6-based WBAN under saturation condition and a noisy channel. We employ a three-dimensional Markov chain to model the backoff procedure as specified in the standard. Probability generating functions (PGFs) are used to compute the performance descriptors of the network. The results obtained from the analytical model are validated by simulation results. Our results indicate that under saturation condition, the medium is accessed by the highest user priority nodes at the vast majority of time while the other nodes are starving.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.10B
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• pp.981-987
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• 2009

Recently, the study on wireless body area network for providing ubiquitous healthcare services has been actively done, including the standardization of the IEEE and others. Wireless body area network is usually configured in tree format using multi-hop communication mode due to the power limitation and the characteristics of human body. In this case, differently from existing sensor network, the wireless body area network tends to be disconnected due to the frequent movement of human body. The number of connections which can be supported at each node has some limitations due to the constraint imposed on power consumption. In this paper, we have proposed a heuristic algorithm for optimal selection of parent node with guaranteed QoS for a disconnected node, which considers the priority on packet transmission. Simulation has been performed to evaluate the performance of the proposed algorithm.

• Electronics and Telecommunications Trends
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• v.28 no.2
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• pp.70-76
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• 2013

인체통신 기술은 유선통신 기술에서와 같이 기기들 간의 연결을 위한 다양한 형태의 케이블이 필요하지 않으므로 기존 유선통신 기술에 비해 편리한 우월성을 가진다. 그렇지만 보안성과 신뢰성은 유선통신의 장점을 넘을 수는 없을 것이다. 무선통신 기술은 초기 네트워크를 구성하기 위하여 서로 복잡하게 주고 받는 절차단계가 필요한 반면, 인체통신 기술은 사용자의 간단한 접촉만으로 통신이 서로 이루어지기 때문에 보다 더 간편하게 연결되며, 사용자 중심의 서비스를 용이하게 제공할 수 있다. 본고는 최근의 인체통신 기술의 기술 동향과 시장 전망 및 표준화 동향을 살펴보고자 한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.9B
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• pp.867-875
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• 2009

The reliability of wireless body area networks is an important research issue since it may jeopardize the vital human life, unless managed properly. In this article, a new modeling and analysis of node misbehaviors in wireless body area networks is presented, in the presence of multi-type failures. First, the nodes are classified into types in accordance with routing capability. Then, the node behavior in the presence of failures such as energy exhaustion and/or malicious attacks has been modeled using a novel Semi-Markov process. The proposed model is very useful in analyzing reliability of WBANs in the presence of multi-type failures.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.3
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• pp.248-259
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• 2001

This paper proposes a human action recognition scheme to recognize nonverbal human communications automatically. Based on the principle that a human body action can be defined as a combination of multiple articulation movements, we use the method of inferencing stochastic grammars to understand each human actions. We measure and quantize each human action in 3D world-coordinate, and make two sets of 4-chain-code for xy and zy projection plane. Based on the fact that the neighboring information among articulations is an essential element to distinguish actions, we designed a new stochastic inference procedure to apply the neighboring information of hands. Our proposed scheme shows better recognition rate than that of other general stochastic inference procedures. ures.

• Food Science and Industry
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• v.50 no.1
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• pp.2-10
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• 2017

Human have eaten various traditional fermented foods for a numbers of million years for health benefit as well as survival. The beneficial effects of fermented foods have been resulted from complex microbial communications within the fermented foods. Therefore, the holistic approaches for individual identification and complete microbial profiling involved in their communications have been of interest to food microbiology fields. Microbiome is the ecological community of microorganisms that literally share our environments including foods as well as human body. However, due to the limitation of culture-dependent methods such as simple isolations of just culturable microorganisms, the culture-independent methods have been consistently developed, resulting in new light on the diverse non-culturable and hitherto unknown microorganisms, and even microbial communities in the fermented foods. For the culture-independent approaches, the food microbiome has been deciphered by employing various molecular analysis tools such as fluorescence in situ hybridization, quantitative PCR, and denaturing gradient gel-electrophoresis. More recently, next-generation-sequencing (NGS) platform-based microbiome analysis has been of interest, because NGS is a powerful analytical tool capable of resolving the microbiome in respect to community structures, dynamics, and activities. In this overview, the development status of analysis tools for the fermented food microbiome is covered and research trend for NGS-based food microbiome analysis is also discussed.