• Journal of the Korean Society of Costume
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• v.61 no.3
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• pp.20-35
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• 2011

The purpose of this study is to investigate war helmets that were worn by high navy officers during the period of Japanese Invasion of Korea(1592~1598). War helmets worn during the War are classified into three types depending on whether they have a visor or 'cheom' and tongues or 'drim'. The war helmets of circumferential type has neither cheom nor drim. Those of cheom type has cheom, but not drim. And those of drim type has both drim and cheom or jeonbi. The war helmets of cheom type consist of a gamtu which is made of steel and looks like a reversed bowl and cheom that surrounds the entire circumference of gamtu. The war helmets of drim type are reclassified into two types in accordance with the shape of the gamtu and whether they have ganju. Of the two types, one type looks like a reversed bowl and has decorations on the top without ganju. The other type looks like a bottle neck and has ganju on the top, decorations above ganju. War helmets were in transition during the period of Japanese Invasion of Korea. Both the war helmets of cheom and drim types were worn during the War. At that time, the officers also wore war helmets having no ganju and looking like a reversed bowl and those having ganju and looking like a bottle neck. During the period, most war helmets were made of steel, but in the 18th and 19th centuries, most of them were made of leather.

• Journal of KIISE:Information Networking
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• v.36 no.3
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• pp.231-242
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• 2009

The EPC-Discovery Service (EPC-DS) is a good representative of the RFID Track & Trace. But this mechanism has several problems. EPC-DS uses centralized server scheme which may arise bottle-neck state and that cannot provide detail trace information of a RFID object. In addition, a trace node requires direct access method to a RFID object or an element which has information of the RFID object for Track & Trace. In this paper, we propose a novel RFID Track & Trace mechanism which based on the SIP presence model and SIP event notification. This mechanism can provide detail trace information and monitoring function, and also can rid the bottle-neck section by combination of SIP methods instead of centralized element.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.203-208
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• 2011

Traffic demand is continuously increasing due to the development of urban areas in Korea. To cope with this, many efforts have been done including constructions of new roadways and increasing the number of lanes of the existing roadways. Those efforts, however, have been performed for only a short segment of target links having similar traffic characteristics. As a result, most urban cities experience bottle-neck phenomena which lead decreasing flow speed and increasing possibilities of accidents. Thus, this study aims to analyze problems of bottle-neck phenomena and effects of balancing number of lanes along the same corridor having similar traffic characteristics. For this, Route 32 passing the city of Daejeon in Korea has been selected as a case study, and a micro-simulation tool, VISSIM, has been adopted for the analysis. The results show that balanced number of lanes along the same corridor with similar traffic characteristics can increase flow speeds and enhance safety.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.5A
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• pp.549-560
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• 2008

In this paper, we propose a new multi-channel MAC protocol to improve the channel efficiency by using two interfaces. Most of previous researches that have considered multi-channel wireless network environments use a common control channel to exchange control signals and they have a bottle neck problem at common control channel as increasing the number of data channels. In the proposed MAC protocol, we separate receiving and transmitting channels so that sending and receiving data and control packets at the same time is possible. It increases the total network throughput. Since there is no common control channel, the network does not suffer from the bottle neck problem. By applying a TDMA scheme, we can avoid packet collisions between data packets and control packets and reduce the possibility of CTS or ACK packet collisions. Simulation results show that the proposed multi-channel MAC protocol improves the total network throughput and channel efficiency compared with the existing method.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.13 no.1
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• pp.18-22
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• 2002

Background and Objectives : It has been pointed out that alcohol intake in human beings induces changes in voice register and maximum phonation time. These changes supposedly result from injection of the vibratory vocal folds. The purpose of this study was to clarify the voice changes associated with alcohol intake and the changes of laryngeal mucosa. Materials and Methods : The subjects included 29 volunteers, including 20 men and 9 women ranging in age from 22 to 31 years. Alcohol intake was accomplished by oral administration of 23% soju 1 bottle (255cc). Serum alcohol concentration levels were evaluated hourly for 3 h after ingestion of alcohol. Seven measurements were performed at pre-alcohol intake and post-alcohol intake hourly : fundamental frequency, jitter, shimmer, noise to harmonic ratio as the acoustic analysis, maximal phonation time, mean flow rate, and subglottal pressure as the aerodynamic analysis. The changes of laryngeal mucosa were evaluated by flexible laryngoscope at each measurement. Results : By comparing the acoustic and aerodynamic data and laryngeal mucosa before and after alcohol intake, there were not remarkable changes (p>0.05). Conclusion : The voice and laryngeal mucosa have not remarkably changed according to alcohol concentration in this study. Furthermore studies on the voice change induced by multiple alcohol concentrations are required.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.7
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• pp.1718-1731
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• 1998

Digital quadrature demodulator is needed for the coherent demodulation in the digital communication systems such as Binary Phase-Shift-Keying, Quadrature Phase-Shift-Keying, and Quadrature Anmplitude Modulation. Conventaionally, the DDFS (Direct Digital Frequency Synthsizer) is used for generating the carrier signal and seperate multi-pliers are used for mixing. And the DDFS is implemented using the ROM (Read Only Memory), which can be a bottle-neck neck when the fast-speed and small-area implementation is required. A new architecture is developed, which employs the circular rotation mode of the CORDIC algorithm for signal mixing as well as carrier generation. To optimize the hardware design parameters, the finiteword-length effects of the proposed implementation arachitecture are analyzed in comparison with a conventional ROM-based architecture. The hardware costs are also estimated, which showed that the proposed architecture occupies only a third of the area of the conventional ROM-based architecture for the same performance. A full-custom VLSI is developed using the proposed architecture.

• Korean Journal of Bronchoesophagology
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• v.18 no.1
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• pp.13-18
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• 2012

Objective This study was conducted to gather basic information of 3D CT in detecting and gaining information of esophageal foreign body (FB) models. Materials and Methods The chest model was made using PVC bottle, rubber balloon and plaster. Fish bone, Persimmon stone were used to mimic foreign bodies of esophageal model. The foreign body models were inserted into the balloon removing air from it and the balloon was sealed. The esophageal FB model was inserted into the chest model. The remaining space in the chest model was filled with fish paste and water to simulate soft tissue around esophagus. CT of chest model was reconstructed three-dimensionally by Rapidia software to make images of foreign body models. The axial CT, MPR image and VOI image were compared with real foreign body materials as to shape, size, location and orientation. Results Esophageal FB models were easily made. CT data gave good 3D images and showed realistic foreign body materials. Conclusion The results indicate the usefulness of 3D CT technique to help in diagnosis of esophageal foreign body models.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06d
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• pp.154-156
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• 2006

본 논문은 기존의 혼잡 제어 기술이 전체 노드들을 위해 설계 되어 싱크 주변에서 생성되는 특별한 혼잡을 해결 할 수가 없기 때문에 싱크 주변 노드를 위한 혼잡 제어 기술을 제안한다. 싱크 주변에서 일어나는 'Bottle Neck' 문제가 일어났을 경우 데이터의 분석에 의한 우선순위결정과 타임 스케줄을 이용한 순차적인 데이터 전송으로 혼잡을 줄이고 그로 인해 데이터의 의미 있는 전송과 신뢰성을 동시에 만족시킨다. 또한 이 기술은 멀티 싱크 또는 모바일 싱크에도 적용 시킬 수 있고, 기존의 전체 노드를 위한 혼잡 제어 기술과 제시하는 기술을 혼용하여 사용할 수도 있다. 본 논문이 제안하는 기법은 혼잡 제어를 하지 않은 상태에서의 데이터 전달 방식에 비해 데드라인 만료 비율이 1.5%이상 감소하였고 프레임 손실율 또한 28%이상 감소하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.785-788
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• 2012

최근 B2C 서비스산업에 있어 기업 간의 경쟁이 심화되고 새로운 비즈니스 가치 창출을 위한 필요 성이 증대되고 있는 상황에서, 기업들은 비즈니스 프로세스 관리 기술에 많은 관심을 기울이고 있다. 프로세스의 최적화를 통해 지속적으로 서비스 품질을 개선하기 위해 비즈니스 프로세스 재설계의 근거로 사용될 수 있는 비즈니스 프로세스 마이닝이 중요한 개념으로 인식되고 있다. 하지만 기존의 프로세스 마이닝에 관한 연구에서는 완성되어 있는 프로세스 로그를 기반으로 워크플로우 기반의 프 로세스 모델을 추출하는 단조로운 형태였기 때문에 다양한 형태의 비즈니스 프로세스를 표현하는데 한계가 있었다. 본 논문에서는 컨벤션, 대학,병원등 광범위한 지식서비스 분야에서 적합한 Prototype 기관을 Test bed로 다양한 프로세스 마이닝 기법으로 분석하여 해당 조직의 문제 프로세스를 발견하 고 개선점을 제안하다. 또한 B2C 서비스 산업에서 적절한 Test bed를 선정하여, 실제 프로세스를 기 존의 legacy system의 event log file에서 분석하여 bottle neck process를 찾아내고, 문제 프로세스를 개선하는 과정을 자동화된 모델링 및 분석 툴을 사용하여 실증적으로 보여준다.

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.49-52
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• 2000

The Multi-Code CDMA systems that are proposed as an effective transmission methodology in the IMT-2000 systems allow higher rate services under the IS-95 CDMA infrastructure. The Multi-Code CDMA systems convert the higher rate data into the lower rate by serial to parallel operation and spread the converted data streams by the multiple walsh codes, and its mobile receiver needs multiple walsh generators and data correlators to demodulate simultaneously multiple walsh code channels. Therefore, the number of data correlators is increased as the number of traffic channels increases. In this paper, we proposed the new structure of the data correlators using walsh overlay coding, the shared accumulator, and FWHT(Fast Walsh Hadamard Transform) algorithm for reducing the bottle-neck effect resulting the increase of the number of data correlators.