• Title/Summary/Keyword: coma

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Laser Micromachining of Submicron Aperture for Electronbeam Microcolumn Application using Piezo Q-Switched Nd:YAG Laser

  • S.J. Ahn;Kim, D.W.;Park, S.S.
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.78-78
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    • 1999
  • Experimental studies of laser micromachining on Mo metal using piezo Q-switched Nd:YAG laser have been performed. Miniaturized microcolumn electron gun arrays as a potential electron beam lithography or portable mini-scanning electron microscope application have recently extensively examined. For these purpose, the electro-static electron lens and deflector system called microcolumn has to be assembled. The conventional microcolumn fabrication technique would gave a limitation on the minimization of aberration. The current technique of a 1 $\mu$m misalignment would lead to ~1.3 nm coma. In order to reduce aberration, assembling the microcolumn component followed by laser drilling should be very beneficial. In this report, we will address the preliminary report of laser micromachining on Mo substrate using piezo Q-switched Nd:YAG laser. The geometrical figures, such as the diameter and the depth of the frilled aperture are dependent upon the total energy of the laser pulse train, laser pulsewidth, and the diameter of laser beam in addition to the materials-dependent parameters.

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Performance Evaluation of Zone-based Registration in COMA Mobile Communication System (CDMA 이동통신 시스템에서 영역기준 위치등록 방법의 성능분석)

  • Baek, Jang-Hyun;Lie, Chang-Hoon
    • Journal of Korean Institute of Industrial Engineers
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    • v.22 no.4
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    • pp.689-703
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    • 1996
  • In this paper, we evaluate the performance of zone-based registration. First, we propose a mobility function for single zone-based registration. And we establish the circumstances of multiple zone-based registration, which is based on the mobility function for single zone-based registration, and perform simulation programs for the circumstances. Using the simulation results, we obtain optimal N, the number of multiple zones which minimizes signalling traffic in radio channels. Results show that in most cases optimal N is 2. Multiple zone-based registration has less signalling traffic in radio channels than single zone-based registration and zone-based registration must be implemented as multiple zone-based registration.

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Raidal Tilt Detection using One Beam and Its Compensation in a High Density Optical Disk Drive (단일 빔을 이용한 고밀도 광 디스크 드라이브의 Radial Tilt 검출 및 보상)

  • Doh, Tae-Yong;Ma, Byung-In;Choi, Byoung-Ho
    • Proceedings of the KIEE Conference
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    • 2001.07d
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    • pp.2299-2301
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    • 2001
  • 광 디스크의 용량을 증가시기키 위해선, 레이저 다이오드의 단파장화와 렌즈의 개구수 증가가 수년 동안 시도되어왔다. 불행히도 이러한 노력들은 디스크 틸트(tilt)로 인해 야기되는 코마(coma) 수차로 인한 부작용을 유발하였다. 이런 문제를 해결하기 위해, 램(random access memory, RAM) 디스크의 경우 몇 가지 검출과 보상 방법이 제안되었다. 그러나, 롬(read only memory, ROM) 디스크의 경우 아직까지 뚜렷한 해결책이 제시되지 않고 있다. 본 논문에서는 8분할 광 검출기에 의해 생성되는 차동 위상 검출(differential phase detection, DPD) 신호를 이용한 고밀도 롬 디스크에서 래디얼(radial) 틸트를 검출하는 방법을 제안한다. 3축 렌즈 구동형 액츄에이터(actuator)를 이용하여 개발한 래디얼 틸트 서보로 검출된 래디얼 틸트를 보상한다. 액츄에이터의 회전이 트래킹(tracking) 서보(servo)에 미치는 영향을 소개한다. 끝으로 제안된 방법의 유용성을 고밀도 롬 드라이브에 대한 실험을 통해 검증한다.

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The Effect of Oral Administration of Ethanol in Ethylene Glycol Intoxication in Dogs (개의 Ethylene Glycol 중독에 대한 에탄올의 경구투여 효과)

  • Part Cheol-Man;Han Hong-Ryul
    • Journal of Veterinary Clinics
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    • v.4 no.1
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    • pp.423-432
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    • 1987
  • The present studies were undertaken in attempt to investigate the therapeutic effect of ethanol in dogs intoxicated with ethylene glycol Three dogs treated with ethylene glycol and other three dogs with ethylene glycol plus 20% ethanol orally were examined on clinical signs, endoscopic views, histopathological findings, and autopsy findings respectively. The results obtained were summarized as fellows : 1. The clinical sings and their severity of dogs intoxicated with ethylene glycol were time related and progressed from vomiting, depression, thirsty, tachycardia, tachypnea, convulsiot ataxia, melena, uremia and coma, but clinical signs of dogs treated with ethylene glycol and ethanol simultaneously only stowed vomiting and thirsty. 2. In the gastroscopic view, the dogs intoxicated with ethyelne glycol showed edematous, hyperemia, errosive and ulcerative lesions in the fundus and body area but the dogs treated with ethylene glycol and ethanol simultanously showed edematous and hyperemic lesions. 3. Oral treatment of ethanol with ethylene glycol simultaneously have reduced the signs of EG intoxications in dogs.

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A Case of Severe Hyponatremia Induced by Radiographic Contrast Agent (조영제 사용으로 유발된 중증 저나트륨혈증 1례)

  • Hong, Jeong-Deok;Lim, In-Seok;Choi, Eung-Sang
    • Childhood Kidney Diseases
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    • v.14 no.1
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    • pp.89-93
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    • 2010
  • Hyponatremia which is a very common electrolyte abnormality in hospitalized patients is defined as a plasma sodium concentration less than 135 mEq/L. Hyponatremia is generally caused by intravascular volume depletion, excessive salt loss and hypotonic fluid overload. It also can be caused by intravascular osmotic agent. Although most cases are mild and asymptomatic, acute severe hyponatremia can cause severe neurologic symptoms, such as seizures and coma. We report a rare case of severe hyponatremia induced by radiographic contrast agent.

Implementation of Patient Monitoring System over COMA Network (CDMA 공중망을 이용한 환자 감시시스템 구현)

  • 고완진;정은호;김성훈;김우식
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04d
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    • pp.85-87
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    • 2003
  • 그동안 부진했던 PDA 산업은 2001년과 지난해를 기점으로 다시금 재도약의 기회를 맞고 있다. 그 연결고리는 바로 PDA와 이동통신(또는 네트워크)의 결합이다. 이동통신이나 네트워크 기능을 결합해 휴대폰과 같은 음성통신은 물론이고, 무선인터넷 활용으로 다양한 정보를 얻을 수 있게 된 것이며 그로 인하여 사용자의 이동성을 보장해주는 다양한 서비스 제공이 가능해졌다. 그러한 서비스 중 하나로서 기존의 유선망을 이용한 원격진료의 불편함을 탈피, 무선망을 이용한 측정시간동안의 시ㆍ공간적 불편함을 해소시킬 수 있는 방법을 제시한다. 피검사자가 실내에서 활동중인 경우에는 무선랜을 통한 원격지관리 그리고 실외에서 활동중인 경우에는 CDMA망을 통한 원격지관리를 가능케 함으로서 어느장소에 있든지 원격지에서 피검사자의 생체신호를 관찰, 진단할 수 있다.

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Renal replacement therapy in neonates with an inborn error of metabolism

  • Cho, Heeyeon
    • Clinical and Experimental Pediatrics
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    • v.62 no.2
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    • pp.43-47
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    • 2019
  • Hyperammonemia can be caused by several genetic inborn errors of metabolism including urea cycle defects, organic acidemias, fatty acid oxidation defects, and certain disorders of amino acid metabolism. High levels of ammonia are extremely neurotoxic, leading to astrocyte swelling, brain edema, coma, severe disability, and even death. Thus, emergency treatment for hyperammonemia must be initiated before a precise diagnosis is established. In neonates with hyperammonemia caused by an inborn error of metabolism, a few studies have suggested that peritoneal dialysis, intermittent hemodialysis, and continuous renal replacement therapy (RRT) are effective modalities for decreasing the plasma level of ammonia. In this review, we discuss the current literature related to the use of RRT for treating neonates with hyperammonemia caused by an inborn error of metabolism, including optimal prescriptions, prognosis, and outcomes. We also review the literature on new technologies and instrumentation for RRT in neonates.

A case report of cocklebur poisoning in Hanwoo (Korean native cattle) (한우에서 발생한 도꼬마리 중독 증례)

  • Jun, Kyoungah;Lee, DongEun;Jeong, DaeEun
    • Korean Journal of Veterinary Service
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    • v.44 no.2
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    • pp.113-117
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    • 2021
  • Cocklebur poisoning in livestock can cause sudden death, with clinical signs include depression, inappetite, blindness, reluctance to move, hypersensitivity, ataxia and coma. The cause of cocklebur poisoning is ingestion of cocklebur sprout or seed, which contains carboxyatractyloside. In December 2020, a 47 month-old Hanwoo suddenly developed ataxia, and died after several hours. Hay mixed cocklebur seeds was fed to Hanwoo for 4 days before the symptoms. At autopsy, petechia and ecchymosis were seen on serous membrane of rumen and intestines. Peritoneal cavities contained a yellowish fluid and, hypoglycemia (Glu <20 mg/dL) was measured in blood test result. Microscopic lesions were karyolysis of centriloular hepatocyte and hemorrhage. Based on autopsy, blood and histopathological test, we diagnosed this case as cocklebur poisoning in Hanwoo.

Ciguatera fish poisoning in Korea: a case report (한국에서 발생한 시구아테라: 증례보고)

  • Kang, Jeong Ho;Lee, Sung Kgun
    • Journal of The Korean Society of Clinical Toxicology
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    • v.19 no.1
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    • pp.55-58
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    • 2021
  • Ciguatera is the commonest syndrome of marine poisoning that is caused by the ingestion of ciguatoxins that accumulate in certain tropical and subtropical finfish. It is endemic throughout the subtropical and tropical regions of the Indo-Pacific and Caribbean and has been rarely reported in Korea. With the expansion of travel, tourism, and the import of fish from the tropics, ciguatera poisoning now affects a diverse population. We report a case of ciguatera in a 70-year-old woman, presenting with general paralysis and coma, which developed after consuming codfish and mackerel in Korea.

Optical Design of a High-numerical-aperture Objective with a Reflective Focal Reducer (반사형 Focal Reducer를 가지는 높은 개구수의 대물렌즈 설계)

  • Jong Ung Lee
    • Korean Journal of Optics and Photonics
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    • v.34 no.6
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    • pp.248-260
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    • 2023
  • A 0.5-numerical-aperture (NA) refractive-reflective objective, composed of a low-NA refractive and a reflective focal reducer, is designed. A 0.25-NA Lister objective is used for the refractive. A two-spherical-mirror system, corrected for spherical aberration, coma, and astigmatism is used for the reflective focal reducer. In spite of high NA, the refractive-reflective objective has an 18-mm working distance and improved imaging performance, compared to the 0.25-NA Lister objective.