• Electronics and Telecommunications Trends
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• v.19 no.1 s.85
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• pp.116-126
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• 2004

인터넷 접속서비스에 대해서는 사전적 규제를 하지 않는 것이 세계적인 추세였으나, 최근 유럽에서는 인터넷 접속서비스에 대해서 사전적 규제를 가할 수 있는 지침이 채택되었다. EU가 2003년 7월에 채택한 「2003년 프레임워크」는 종래의 수직 통합형 산업구조가 인터넷 기술발전에 따라 물리적인 네트워크, 전송서비스, 콘텐츠로 정보통신산업이 층별로 세분화되어 가고 있다는 사실을 반영한 새로운 규제체계로 평가할 수 있다. 이 규제체계의 방향성은 경쟁이 미진한 분야에는 사전적 규제, 경쟁이 활성화된 분야에는 사후적 규제를 가하는 것이다. 본 고의 목적은 일본의 인터넷 접속서비스에 관한 시장 및 규제 동향을 소개하는 것이다. 여기에서는 먼저 일본의 인터넷 접속서비스 사업자의 현황을 개관한 후, 인터넷 접속서비스에 대한 정부차원에서의 규제동향을 고찰한다. 일본에서는 인터넷 접속서비스에 대하여 사전적 규제를 하지 않고 있다는 점을 감안하여 일본의 대표적 ISP 사업자라 할 수 있는 JPIX와 NTT 동서를 대상으로 인터넷 접속서비스의 사업현황과 이들 기업에 접속하기 위한 접속조건 등을 살펴본다. 맺음말에서는 현재 일본에서 이루어지고 있는 인터넷 접속서비스에 대한 규제동향을 우리나라와의 비교 관점에서 고찰하고 우리나라에의 시사점을 제시하고자 한다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.873-876
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• 1993

A fuzzy controller designed by mini-max-gravity(MMG) method is essentially nonlinear with respect to the controller's input and output relationship, and stability analysis is thus needed to construct a stable control system. This paper deals with a design method of a position-type MMG fuzzy controller stable in a sense of Lyapunov when considered is a single-input-single-output linear, stable plant. We first introduce a method to construct a Laypunov function by using an eigen-value of A matrix of the linear, stable plant dynamics and then we derive an asymtotic stability condition in terms of scale factors for fuzzy state variables and controller gain. The stability condition is found reasonably practical through comparing the theoretical stability region with that obtained from simulations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9B
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• pp.1579-1587
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• 2000

This paper presents the properties of the RF part in the receiving system based in IMT-2000 terminal technology. It mainly discuss the RF parameter performance of the receiving system for mobile telecommunication comparable to IS-98A and J-STD-018 specifications of commercially available CDMA and PCS, and is to anticipate the processing gain of the IMT-2000 receiving system, processing gain according to data processing rate, and terminal noise figure according to processing gain, relationship between noise figures according to Eb/Nt, Ioc. It is performed by such analysis method as CDMA and PCS receiving systems. Transmission bandwidth is n$\times$1.25 MHz(n=1, 3, 6, 9, 12) which is recommended by Qualcomm and NTT, the leading company in cdma 2000. Data transmission rate of IMT-2000 is classified into three cases as in moving vehicle environment of 144Kbps, outdoor pedestrian environment of 384Kbps, and indoor office environment of 2Mbps

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.911-914
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• 2004

웹 서비스 기반기술의 표준화와 웹 서비스의 필요성이 증가함에 따라 많은 서비스들이 개발되어지고 있다. IBM, Microsoft, SAP, NTT DOCOMO에서 운영하고 있는 UBR(UDDI Business Registry)을 이용하여 웹 서비스 사용자들은 많은 서비스들을 즉시 사용할 수 있다. 하지만, 현재 제공되어지고 있는 웹서비스들 중에서 정상적인 서비스를 제공하고 있는 개수는 등록되어있는 웹 서비스의 개수에 비해 극히 적다. 이러한 상황은 서비스를 사용하려는 사용자에게 가용한 서비스를 찾기 위해 많은 노력과 시간을 요구하게 된다. 이에 본 논문에서는 UBR로부터 검색되어진 웹 서비스들 중에서 가용한 서비스들만을 분리하여 사용자에게 제공하는 시스템을 제안한다. 본 시스템은 UBR 검색 후 이동 에이전트를 사용하여 테스트를 수행, 가용한 서비스 리스트를 사용자에게 제공함으로써 사용자가 검색되어진 웹 서비스를 즉시 사용할 수 있도록 한다.

• Journal of Life Science
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• v.30 no.4
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• pp.321-330
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• 2020

The aim of this study was to investigate the effect of copper (II) chloride (CuCl₂) on zebrafish. Zebrafish were exposed to various CuCl₂ concentrations and subjected to different exposure times to determine the median lethal concentration (LC₅₀) values. To evaluate stress responses, we measured whole-body cortisol levels and behavioral parameters using the open field test (OFT) or the novel tank test (NTT). The zebrafish were exposed to CuCl₂ solution at concentrations of 1.5-150 ㎍/l or a vehicle for 1 hr before behavioral tests or sample collection for whole-body cortisol. The LC₅₀ values were 30.3, 25.3, and 14.8 ㎍/l at 24, 48, and 96 hr, respectively. The NTT showed that mobility, velocity, and distance covered were significantly lower in zebrafish exposed to CuCl₂ than in the control group (p<0.05), while the turn angle was significantly higher in zebrafish exposed to a CuCl₂ concentration of 150 ㎍/l than in the control group (p<0.05). The OFT also showed that mobility, velocity, and distance covered were significantly lower and the turn angle and meandering were significantly higher in zebrafish exposed to all concentrations of CuCl₂ than in the control group (p<0.05). The whole-body cortisol levels were significantly higher in zebrafish exposed to CuCl₂ than in the control group (p<0.05). These results suggest that exposure to lethal CuCl₂ concentrations induces an intense toxic and stress response in zebrafish, causing behavioral changes and increasing whole-body cortisol levels.

• Journal of Navigation and Port Research
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• v.47 no.1
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• pp.18-24
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• 2023

After the Great East Japan Earthquake, many reports and books that compiled testimonies of adult victims were published. Thus, refugee situations are well known, but information on the refugee situations of Japanese students is not. This is because what actions the students took and how they sought refuge from an earthquake or tsunami have not been fully recognized. The purpose of this study was to examine and analyze students' refuge behavior in the Great East Japan Earthquake and to predict the refuge behavior of students affected by future disasters. The results of the study showed that students passively acquired information about earthquakes and tsunamis and that their refuge behavior was highly dependent on adults. Immediately after an earthquake, people tended to protect themselves and stay in place until the shaking stopped. However, they tended to move to another place after the shaking occurred frequently. Students living on ria coastlines were likely to move to high places to escape the threat of earthquakes and tsunamis, whereas students living in plain regions were likely to move vertically to tall buildings, such as schools. As for the mode of movement to refugee shelters, the students arrived at the final refugee shelters in one move, and it is assumed that the refugee shelters should be decided in advance and the students should move there.

• Industrial Engineering and Management Systems
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• v.12 no.4
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• pp.351-358
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• 2013

This paper proposes a multiobjective model describing the trade-offs involved in selecting the locations of drop-off boxes for collecting used products and transporting these products to designated locations. We assume the following reverse flow of used products. Owners of used products (cellular phones, digital cameras, ink cartridges, etc.) take them to the nearest drop-off box when the distance is reasonably short. We also assume that owners living closer to drop-off boxes dispose of more used products than do owners living farther from drop-off boxes. Different types of used products are collected, with each type requiring its own drop-off box. A transportation destination for each product is specified. Three objectives are considered: maximizing the volume of used products collected at drop-off boxes; minimizing the cost of transporting collected products to designated locations; and minimizing the cost of allocating space for drop-off boxes. We formulate the above model as a multiobjective integer programming problem and generate the corresponding set of Pareto optimal solutions. We apply the model to an area using population data for Chofu City, Tokyo, Japan, and analyze the trade-offs between the objectives.

• Journal of information and communication convergence engineering
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• v.12 no.4
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• pp.228-236
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• 2014

One of major purposes of these standard technologies is to ensure interoperability between entities from different vendors and enable interworking between various technologies. As interoperability and interworking are essential for machine-to-machine communications (M2M) and Internet of Things (IoT) for them to achieve their ultimate goal, i.e., things to be connected each other, multiple standards organizations are now working on development M2M/IoT related specifications. This paper reviews the current activities of some of the most relevant standardization bodies in the area of M2M and IoT: third-generation partnership project (3GPP) core and radio network aspects, broadband forum, and oneM2M. The major features and issues being focused upon in these standards bodies are summarized. Finally, some key common trends among the different bodies are identified: a common service layer platform, new technologies mitigating an explosive growth of network traffic, and considerations and efforts related to the development of device management technologies.

• Journal of Multimedia Information System
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• v.7 no.2
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• pp.147-156
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• 2020

The author Nakajima was involved in the field of disaster communications and emergency medical care as guest research scientist at the Fukushima Nuclear Accident Independent Investigation Commission established by the National Diet of Japan and reviewer of the Commission's report, and Kurokawa was the chairman of this Commission. Looking back over a decade, we are on the liability issue of bureaucrats and telecom operators, so it's becoming clear what was hidden at the time. The battery of NTT DoCoMo's mobile phone repeaters had a capacity of only about 24 hours, and communication failures increased after one day. The Government also failed to issue an announcement of "Vent from reactor" under the Telecommunications Act Article No. 129. This mistake lost the opportunity to use the third-party telecommunications (e.g. taxi radios). Furthermore, as a result of LASCOM (telecommunications satellite network for local governments via GEO) and a variety of unexpected communication failures, the evacuation order "Escape!" could not be notified to the general public well. As a result, the general public was exposed to unnecessary radiation exposure. Such bureaucratic slow action in emergencies is common in the response to the 2020 coronavirus.

• Asian Journal of Business Environment
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• v.9 no.4
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• pp.5-13
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• 2019

Purpose - This research is aimed to investigate the impact of the Information and Communication Technology (hereinafter ICT) development index and ICT investment on Indonesian economic growth. Research design, data and methodology - The data used consist of ICT development index, government expenditure on ICT sector, and economic growth from 33 provinces in Indonesia from 2012 to 2015. Based on the Networked Readiness Index published by the World Economic Forum (WEF), Indonesia was ranked 80^th among 142 countries in 2012 and had climbed 64^th in 2014. This indicates that the businesses in Indonesia have adopted ICTs to increase productivity and expand their activities. Panel data regression analysis is performed to reveal the change of the impact over time in each of the provinces. Result - The ICT development index and government expenditure for ICT have a positive effect on the economic growth of all provinces, although the impact is different in each of the provinces. There is a digital gap between the provinces, especially the large digital gap occurring with DKI Jakarta. The provinces of Eastern Indonesia such as NTT and Papua are still relatively slow in development of ICT. Conclusions - ICT development index and allocation of local government expenditure for ICT have significant effect on economic growth. ICT development index has a bigger role in increasing economic growth.