• Journal of The Korean Society of Clinical Toxicology
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• v.7 no.1
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• pp.26-31
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• 2009

Hydrogen sulfide is a by-product of decayed organic material and is ubiquitously found as an ingredient of manufacturing reagents or as an undesirable by-product of the manufacturing or industrial processing. Hydrogen sulfide is a chemical asphyxiant and interferes with cytochrome oxidase and aerobic metabolism. It has thus been deemed an important cause of work-related sudden death. This gas is particularly insidious due to the unpredictability of its presence and concentration and its neurotoxicity at relatively low concentrations, causing olfactory nerve paralysis and loss of the warning odor. Here, we report two cases of comatose patients presenting after accidental exposure to hydrogen sulfide gas.

• Journal of Communications and Networks
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• v.8 no.3
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• pp.290-296
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• 2006

In this paper, a generalized blind adaptive algorithm is introduced for multi-user detection of direct sequence code division multiple access (OS-COMA) wireless communication systems. The main property of the proposed algorithm is its ability to resolve the multipath fading channel resulting in inter symbol interference (ISI) as well as multiple access interference (MAI). Other remarkable properties are its low complexity and mitigation to the near-far problem as well as its insensitivity to asynchronous transmission. The proposed system is based on the minimization of the output energy and convergence to the minimum mean square error (MMSE) detector. It is blind in the sense that it needs no knowledge of the other users' signatures, only the intended user signature and timing are required. Furthermore, the convergence of the minimum output energy (MOE) detector to the MMSE detector is analytically proven in case of M-ary PSK. Depicted results show that the performance of the generalized system dominates those previously considered. Further improvements are obtained when multiple input multiple output (MIMO) technique is employed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.6A
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• pp.885-892
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• 2000

A multi-used detector(MUD) using a radial basis function(RBF) network is proposed in a multicarrier-code division multiple access (MC-CDMA) system. In the proposed scheme, a RBF network is connected to the frequency domain in order to effectively utilize the frequency diversity. Simulations have been performed over the frequency selective and multipath fading channel. From these simulations, the proposed receiver is verified to be used for making the performance improvement in combating near-far effects and increasing the number of active users. The system capacity is increaed about 1.8 times at a BER of $10^{-3}$ under a single cell when the proposed scheme is compared with MUD using a parallel interference canceller(PIC).

• Transactions of the Society of Information Storage Systems
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• v.3 no.4
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• pp.191-195
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• 2007

The optical disc drive has used a high NA objective lens and a shorter wavelength laser diode for high recording density. But high NA and shorter wavelength cause several margins to become short. Focusing and tracking servo has to be more accurate and active tilt compensation mechanism is also needed for coma aberration compensation. In this paper, we proposed 3-axis moving magnet type actuator. For 3-DOF motion, moving coil actuator has to be equipped with 6 wires for supplying 3 independent signals. However, moving magnet type actuator doesn't need to change the configuration of wires because coils are in stator. So, we added a tilt mechanism to the 2-axis moving magnet actuator which is designed in previous research. Addition of the tilt mechanism cuts down the focus sensitivity. So, maximization the tilting sensitivity and securing the focusing sensitivity are objectivities of this research. DOE (design of experiments) procedures of electromagnetic circuit are performed for parameter study and the optimization is also performed to maximize the tilt sensitivity. And then the final design is suggested and its performance is verified by FE simulation.

• Korean Journal of Optics and Photonics
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• v.4 no.3
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• pp.252-259
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• 1993

A holosymmetric four-mirror system with unit magnification is designed for use in the micro-lithography using a deep ultraviolet wavelength of $0.248 {\mu}m$(KrF excimer laser line). In the holosymmetric system all orders of coma and distortion are zero. By applying this principle to the 4-spherical mirror system, we have obtained only one exact solution for the unit magnification holosymmetric four-spherical mirror system with all zero third order aberrations. For correction of the residual higher order aberrations of the system, aspherization is introduced keeping the holosymmetric properties. We have obtained near diffraction-limited performance for the wavelength of 0.248 pm within N.A. of 0.33 and image field diameter of 7.6 mm.

• Biomolecules & Therapeutics
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• v.8 no.3
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• pp.255-261
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• 2000

WooHwangChungSimWon is a traditional prescription for treating with hypertension, arteriosclerosis, coma, and stroke in China, Korea, and Japan. In the new presciption of WooHwangChungSimWon, the covet is substituted for the musk, the major component of WooHwangChungSimwon, because of the prohibition law about the musk. We have made a comparative study of the effects on the ischemic damage between the musk containing and civet containing WooHwangChungSimWon. In order to investigate the effects of WooHwangChungSimWon on the ischemic damage, each samples were administrated for 12 days, ischemia was induced for 10 minutes at 7th day, and immunohistochemistry was performed in the region of hippocampus of mongolian gerbils. According to the result of immunohistochemistry, the survival rates of neuroal cells in the hippocampal CA1 region are 37.8% in the high dose of musk containing WooHwangChungSimWon (HM-WHCSW) administrated group, 27.8% in low dose of civet containing WooHwangChungSimWon (LC-WHCSW), and 35.5% in high dose of civet containing WooHwangChungSimWon (HC-WHCSW) administrated group. These survial rates were significantly different from the survival rate of sham control group (14.4%). The results suggest that all the samples except the low dose of musk containing WooHwangChungSimWon (LM-WHCSW) have protective or preventive effects on cerebral ischemia.

• Korean Journal of Pharmacognosy
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• v.31 no.4
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• pp.373-382
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• 2000

This study was performed to investigate the antithrombotic activity and protective effect of hexane fraction of Kamihyulbuchukeotang (KHCTH) on brain injury by KCN and MCA occlusion a prescription of HCT added with Lumbricus and Notoginseng Radix. Experiemental parameters are brain ischemia by MCA occlusion assay, KCN-induced brain injury, pulmonary thrombosis and platelet aggregation assay. The results were summarized as follows; 1. KHCTH extracts significantly inhibited the duration of KCN-induced coma (67%) and mortality (80%). 2. KHCTH extracts significantly suppressed brain ischemic area and edema following MCA occlusion and protected neuron cells as compared with control data. 3. KHCTH extracts inhibited pulmonary thrombosis induced by collagen and epinephrine. 4. KHCTH extracts inhibited platelet aggregation induced by collagen, ADP as agonist up to 76.9% and 32.3% respectivey at 1 mg/ml more effective than water extract of KHCT These data suggested that KHCTH could be applied as the protector of brain ischemia and injury and antithrombotic agent.

• Korean Journal of Community Nutrition
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• v.3 no.3
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• pp.430-439
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• 1998

This study was performed to investigate the nutritional status of neurosurgical tube-fed patients. The objective of this study was to improve the nutrition management of tube-fed patients. The current practices of tube feeding and enteral nutrition formula as for 95 patients in the hospital were examined by reviewing patients charts, and interviewing patients, nurses and their family members. The results are summarized as follows ; 57.9% of patients that received the formula showed a decrease in mental status. Among the subjects, 55.7% had nervous system diseases due to old age. Most of the tube-fed patients were hospitalized in the emergency room and while hospitalized, the status of their respiratory organ was abnormal. The method of tube-feeding was by Bolus injection and the type of the tube was a 16Fr size silicone tube. The amount of the injection per day while tube-feeding was on average 1424kcal for men and 1322kcal for women and the calories per day ranged from 1000-1500kcal(50.5%). The injection volume averaged 332.7ml and 45% of patients received more than 300ml per injection. The tube feeding intake rate was 127.9ml/min with 50% of subjects in the range of 50-100ml/min and 10% at 20ml/min. The longer the hospitalization, the older age, coma status, and the higher tube feeding rate, the more decreased were the biochemical parameters.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.49-51
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• 2003

가입자망과 메트로 광 가입자망에서 광범위한 적용범위에 대해 광 기술을 선도하는 기존의 WDM은 증가하는 사용자 수를 수용하는 데 어려움을 가지며 WDM은 채널간의 잡음에 의한 제한과 유효 채널의 최대가 WDM 채널에서 광 증폭기 이득의 균일성에 의해 제한받는다. 따라서 사용자 수를 증가시키고 데이터량을 확장시킬 수 있는 CDMA 기술 도입이 하나의 대안으로 요구된다. 본 논문에서는 SMF에서 수십 km 거리를 갖는 가입자망에서 Prime sequence code를 사용한 2.5Gb/s 광 COMA 신호의 색분산 패널티에 대해 연구하였다. 시스템 모델에서, 색분산 패널티, 파형과 디코드된 신호의 아이 다이어그램(eye diagram)이 결과로써 보여지며, prime sequence code 수의 증가에 대해 Chirp 파라미터를 갖는 코드화된 신호의 색분산 패널티를 보인다. 이러한 접근은 pseudo-orthogonality를 가지는 비동기식 광 CDMA의 디자인에 특히 적합할 것이다.

• 한국IT서비스학회:학술대회논문집
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• 2003.11a
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• pp.202-217
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• 2003

현재 국내 이동통신기술과 서비스 수준은 전세계 이동통신 서비스 국가 중에서 선두를 이루고 있는 국가 중 하나이며, 다양한 데이터 정보 서비스 수준은 이동통신분야에서는 새로운 시장을 주도적으로 창조해 나가고 있다고 본다. COMA기반의 이동통신 단말기의 전세계 점유율은 1위와 2위를 앞서거니 뒷서거니 하고 있으며, 또한 초고속 인터넷망의 보급율과 인터넷 이용율은 전세계에서 최고를 자랑하고 있다. 이에 발맞추어 기업과 통신사업자의 이동통신망 이용률과 가입자 비율도 상당히 앞서고 있으며. 특히 초고속통신망 가입자는 세계 최고의 인프라와 시장을 형성하는 등 이에 따른 이동통신분야의 어플리케이션 시장이 매우 발달되어 있다. 나아가 한국의 이동통신기술발전에 따른 콘텐츠 개발과 서비스는 매우 다양하게 진행되고 있다. 그러나 지속적으로 제 3의 이동통신시대에 부응하는 멀티미디어형 콘텐츠의 개발과 새로운 기술 환경에 대응하는 생활형 콘텐츠의 창안은 매우 중요한 이슈로 등장이 되고 있다. 이에 미국에서 1988년부터 연구되어 왔고, 일본에서 의용적으로 추진하고 있는 유비쿼터스 환경의 국내 연구와 도업은 시급하게 진행되어야 할 차세대 통신산업의 중요한 화두라고 본다. 이 보고서에서는 유비쿼터스 환청 기반의 콘텐츠의 개요와 개발방향 및 가능성 등을 중심으로 내용을 구성하고 있다. 사람과 사물간의 인터랙티브를 유도하는 유비쿼터스 네트워크 기반에 필요한 콘텐츠와 콘텐츠 기반의 다양한 애플리케이션과 서비스 등을 연구함으로써 보다 한 차원 높은 정보통신을 통한 삶의 질 개선과 유비쿼터스 기반 콘텐츠 산업의 국내 도입과 활성화 가능성을 모색하는데 있다.