• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.239-244
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• 2018

A 59-year-old man with no specific medical or family history complained of chest pain and became unconscious. A member of his family, who was a witness, called 119 and gave him dispatcher-assisted cardiopulmonary resuscitation, followed by defibrillation using an automated external defibrillator placed in his apartment. Afterward, he was given two sessions of defibrillation by the 119 emergency squad, then transferred to an emergency medical center with the return of spontaneous circulation. The patient was discharged with cerebral performance category (CPC) 1 15 days later. While dispatcher-assisted cardiopulmonary resuscitation and defibrillation is at its beginning stage in South Korea, this case seems to demonstrate its effectiveness. Moreover, this case suggests it can be particularly useful for helping untrained witnesses use an automated external defibrillator, which may have important implications in regions in which there are delayed responses of the 119 emergency squad to the site. It is also important to develop a plan for improving witness access to and quantitative supply of the South Korean public access defibrillation (PAD) program.

• The Journal of the Acoustical Society of Korea
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• v.22 no.3
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• pp.217-223
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• 2003

A novel cooling method induced by acoustic streaming generated by ultrasonic vibration at 30㎑ is presented. Ultrasonic vibration is obtained by piezoelectric devices and the maximum vibration amplitude of 50 m is achieved by including a horn, mechanical vibration amplifier in the system and making the complete system resonate. To investigate the enhancement of heat transfer capability of acoustic streaming, the temperature variations of heat source and air in the vicinity of heat source are measured in real-time. It is observed that acoustic streaming is instantly induced by ultrasonic vibration, resulting in the significant temperature drop due to the bulk air flow caused by acoustic streaming. In addition, it is observed that the cooling effect on the heat source is maximized when the gap between the ultrasonic vibrator and heat source coincides with the multiples of half-wavelength of the ultrasonic wave. This fact results from the resonance of the sound wave. The theoretical analysis of the dependence on the gap is also accomplished and verified by experiment. The advantage of the proposed cooling method by acoustic streaming is noise-free due to the ultrasonic vibration and maintenance-free because of the absence of moving parts. Moreover. This cooling method can be utilized to the nano and micro-electro mechanical systems, where the fan-based conventional cooling method can not be employed.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.42 no.3
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• pp.31-38
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• 2005

This paper proposes an implementation method of intelligent characters that can properly adapt to action patterns of opponent characters in fighting games by using genetic algorithm. For this intelligent characters, past actions patterns of opponent characters should be included in the learning process. To verify the effectiveness of the proposed method, two types of experiments are performed and their results are compared. In first experiment(exp-1), intelligent characters consider current action and its step of an opponent character. In second experiment (exp-2), on the other hands, they take past actions of an opponent characters into account additionally. As a performance index, the ratio of score obtained by an intelligent character to that of an opponent character is adopted. Experimental results shows that even if the performance index of exp-1 is better than that of exp-2 at the beginning of stages, but the performance index of exp-2 outperforms that of exp-1 as stages go on. Moreover, optimum solutions are always found in all experimental cases in exp-2. Futhermore, intelligent characters in exp-2 could learn moving actions (forward and backward) and waiting actions for getting more scores through self evolution.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.1
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• pp.139-145
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• 2016

Dumbbell is the most basic topology that can be used in almost all kind of network experiment within it or just by little expansion. While Transmission Control Protocol TCP is the basic protocol that is used for the connectivity among networks and stations. TCP major and basic goal is to provide path and services to different applications for communication. For that reason TCP has to transfer a lot of data through a communication medium that cause serious congestion problem. To calculate the congestion problem, different kind of pre-cure solutions are developer which are Loss Based Variant and Delay Based Variant. While LBV keep track of the data that is going to be passed through TCP protocol, if the data packets start dropping that means congestion occurrence which notify as a symptom, TCP CUBIC use LBV for notifying the loss. Similarly the DBV work with the acknowledgment procedure that is used in when data ACK get late with respect to its set data rate time, TCP COMPOUND/VAGAS are examples of DBV. Many algorithms have been purposed to control the congestion in different TCP variants but the loss of data packets did not completely controlled. In this paper, the congestion control algorithms are implemented and corresponding results are analyzed in Dumbbell topology, it is typically used to analyze the TCP traffic flows. Fairness of throughput is evaluated for different TCP variants using network simulator (NS-2).

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.145-155
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• 2012

At present, Seoul City is putting the bus exclusive lane system into practice according to mass transit revitalization policy. Starting with the installation of roadside bus exclusive lane in the past, at present, even the road sections for central- lane bus exclusive lane system are on the increase. The purpose of this research is to analyze the factors giving impacts on bus accident on central bus exclusive lane and roadside bus exclusive lane. In case of the central bus exclusive lane, the 6 variables, such as the number of bus routes, number of access & entrance to central lanes patterns, whether the stop line of central lanes retreats or not, separated distance between the stop line of central lanes and crosswalks, traffic volume, and number of bus routes stopping at bus stops on reversible lanes, were found to have a significant influence on bus accidents. In case of roadside bus exclusive lane sections, the four variables such as the number of right-turn bus routes, whether to be chronic illegal parking & stopping, time for the walk signal, and forms of land use, etc. were found to have a significant influence on bus accident.

• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.73-79
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• 2000

해저지각 시추 프로그램 (Ocean Drilling Program: 이하 ODP 라함)은 해저 분지 연구를 통해서 지구의 진화와 구조를 밝히기 위해서 조직된 기구로 지구과학 분야에서는 세계에서 가장 규모가 크고 성공적인 연구사업을 추진하고 있다. 이 프로그램은 심해저시추 프로그램 (DSDP: Deep Sea Drilling Project)의 뒤를 이은 연구 사업으로 1983년부터 시작되었으며 지구 과학자들은 다양한 해저지질 및 지구물리 자료를 제공받고 있어 지구 지각과 해저 분지의 기원과 진화 및 구조에 대한 연구에 매우 커다란 도움을 받고있다. 한국은 2년 간의 가입 타당성 조사 끝에 1996년에 호주, 카나다와 콘소시움을 형성하여 ODP에 가입했고 그 후 대만이 합류하여 환태평양 콘소시움 (PacRim)을 이루었다. 한국이 ODP에 가입한 뒤 한국 사업단이 조직되고 정관이 제정되었으며 상임위원회, 과학위원회 및 사무국이 결성되었다. 아울러 한국이 ODP에 본격적으로 참여한 1998년이래 현재까지 두 명의 한국 과학자가 시추선에 승선하였고 승선 후 세계적으로 유명한 과학자들과 함께 공동 연구를 수행하고 있다. 한국이 ODP에 가입하게 됨에 따라 세계적으로 4곳의 시료저장소에 보관되어 있는 기존의 시추 시료 및 자료를 이용할 수 있으므로 국내 지구 과학자들은 시추선 승선 뿐 만이 아니라 ODP 시료와 자료를 적극 이용하여 국내 지구과학이 진일보하는 계기를 마련하게 되었다. 따라서, 한국 ODP 사업단의 개요와 활동, 그리고 향후 연구 사업의 방향을 소개하여 지구 과학을 연구하는 학계, 연구계 및 산업계에 종사하는 지구과학 전문가들에게 ODP 사업에 대한 이해를 증진시키고 시추선 승선과 시료 및 자료 이용에 대해 적극적으로 참여할 수 있는 정보를 제공코자 한다.정이 이뤄져야 할 것으로 보인다. 또한 내부파와 음파의 상대적인 진행 방향에 따라 음장변화가 크게 다를 것이 예상되므로 이를 규명하기 위해서는 궁극적으로 3차원적인 음장분포 연구가 필요하다. 음향센서를 해저면에 매설할 경우 수충의 수온변화와 센서 주변의 수온변화 사이에는 어느 정도의 시간지연이 존재하게 되므로 이에 대한 영향을 규명하는 것도 센서의 성능예측을 위해서 필요하리라 사료된다.가지는 심부 가스의 개발 성공률을 증가시키기 위하여 심부 가스가 존재하는 지역의 지질학적 부존 환경 및 조성상의 특성과 생산시 소요되는 생산비용을 심도에 따라 분석하고 생산에 수반되는 기술적 문제점들을 정리하였으며 마지막으로 향후 요구되는 연구 분야들을 제시하였다. 또한 참고로 현재 심부 가스의 경우 미국이 연구 개발 측면에서 가장 활발한 활동을 전개하고 있으며 그 결과 다수의 신뢰성 있는 자료들을 확보하고 있으므로 본 논문은 USGS와 Gas Research Institute(GRI)에서 제시한 자료에 근거하였다.ऀĀ耀Ā삱?⨀؀Ā Ā?⨀ጀĀ耀Ā?돀ꢘ?⨀硩?⨀ႎ?⨀?⨀넆돐쁖잖⨀쁖잖⨀／ࠐ?⨀焆덐瀆倆Āⶇ퍟ⶇ퍟ĀĀĀĀ磀鲕좗?⨀肤?⨀⁅Ⴅ?⨀쀃잖⨀䣙熸ጁ↏?⨀

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.4C
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• pp.331-340
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• 2006

In this Paper, we propose to extend the TSS-LS(Two-Step Search scheme with Linear search based Second step) scheme which was already proposed by the authors for coherent UWB(Ultra Wide Band) systems, to rapid and reliable acquisition of noncoherent UWB systems in multipath channels. The proposed noncoherent TSS-LS employing simple energy window banks utilizes two different thresholds and search windows to achieve fast acquisition. Furthermore, the linear search is adopted for the second step in the proposed scheme to correctly find the starting point in the range of effective delay spread of the multipath channels, and to obtain reliable BER(Bit Error Rate) performance of the noncoherent UWB systems. Simulation results with multipath channel models by IEEE 802.15.3a show that the proposed two-step search scheme can achieve significant reduction of the required mean acquisition time as compared to general search schemes. ]n addition, the proposed scheme achieves quite good BER performance for large signal-to-noise ratios, which is favorably comparable to the case of ideal perfect timing.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.155-163
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• 2009

The Oriental white stork (Ciconia boyciana) is an endangered species in Korea as well as in the world. In order to provide information on foraging habitats for releasing storks to the wild, we studied the foraging behavior of the species according to different food densities and water levels. We released two individuals, male and female, after enclosing a study site with a fence and cutting out a part of two or three primary feathers. Research was conducted from 20 June to 16 August 2008 at Whawon-ri, Mewon-myung, Chungcheongbuk-do, South Korea. We investigated habitat patch usage, foraging efficiency, and foraging methods of the feeding individuals in the different food densities and water levels. The storks invested more for foraging time and trials, and they captured more food in a habitat of high food density than others. The female invested more time and captured food most in a habitat of lowest water depth while the male in a habitat of middle water depth. However, foraging efficiency did not differ significantly among habitats of food density and water depth, and only differed between male and female by ways of foraging method. From this study we suggest that the storks select foraging habitats and foraging methods under different conditions of food density and water depth.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.2
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• pp.108-113
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• 2014

This study was conducted to evaluate the performance of Italian ryegrass cultivars for salt tolerance under in vitro condition. Italian ryegrass cultivars such as Greenfarm, Florida80, Kowinearly, and Hwasan101 were tested for their tolerance to various sodium chloride levels (0, 50, 150, 250, and 350 mM). The seed germination, growth, and activities of antioxidant enzymes were investigated under salt treatment. Physiological traits such as seed germination percentage, germination period, shoot and root length, and dry weight were suppressed under entire salt stress conditions. The results indicated that the highest germination percentage and shoot and root length were recorded at normal conditions. Increased sodium chloride levels caused a significant reduction in the seed germination and growth rate. Among the four tested cultivars, Italian ryegrass 'Hwasan101' could be considered as salt tolerant owing to its higher germination percentage, better seedling growth and antioxidant activities under salinity stress, whereas Greenfarm cultivar was more sensitive. The selection of Italian ryegrass cultivars for greater tolerance to saline environment would allow greater productivity from large saline lands.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3B
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• pp.380-389
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• 2010

Since the internet is intend to be the best effort service, the system that stream a large amount of high quality medias need a techniques to overcome the network status for implementation. In this paper, we design and implement a method that estimate quickly whether network permits the needed bandwidth of media and a method that control QoS through that. Presented system uses Relative One-Way Delay(ROWD) trend in the case of the former, and leverages temporal encoding among Scalable Video Coding(SVC) that is apt to apply real time comparatively in the case of the latter. The streaming server classifies the medias by real time to several rates and begins transmission from top-level and is reported ROWD trend periodically from the client. In case of the server reported only 'Increase Trend', the sever decides that the current media exceeds the available bandwidth and downgrades the next media level. The system uses probe packet of difference quantity of the target level and the present level for upgrading the media level. In case of the server reported only 'No Increase Trend' by the ROWD trend response of the probe packet from client, the media level is upgraded. The experiment result in a fiber to the home(FTTH) environment shows progress that proposed system adapts faster in change of available bandwidth and shows that quality of service also improves.