• Applied Microscopy
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• 제25권4호
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• pp.115-123
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• 1995

This study was carried out to observe the functional ultrastructures of photoreceptor cells in frog(Rana catesbeiana) retina using transmission electron microscope. The photoreceptor cells are divided into two types-rod and cone cells-consist of outer and inner segment. The long outer segment of rod cell contains dense stacks of membrane and formed vertical and horizontal folds. The outer segment of cone cell is small, and vertical and horizontal folds are not exist. The electron dense cytoplasm of rod cell contains compact mitochondria, Golgi complexes, and endoplasmic reticula. The inner segment of cone cell shows low electron density and contains a large lipid droplet in the upper part of inner segment. In addition, cone cell contains many mitochondria, Golgi complexes. rough endoplasmic reticula, ribosomes and numerous glycogen particles. It is believed that these ultrastructural characteristics are closely associated with photoreceptive function of photoreceptor cells in frog retina.

• 대한바이러스학회지
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• 제29권3호
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• pp.155-163
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• 1999

Hantaan virus (HTNV), the etiologic agent of hemorrhagic fever with renal syndrome (HFRS), belongs to the genus Hantavirus, and has three single negative stranded RNA genome segments. HTNV strain Howang isolated from the blood of severe case of Korean HFRS is more virulent than HTNV 76/118 and the M and S genome segments' nucleotide sequence of Howang strain showed 93.5% and 94% homology to each segment of HTNV 76/118. We have obtained 6533 nucleotides long sequence of the L genome segment of Howang strain using reverse transcriptase in conjunction with PCR amplification and compared to other hantaviruses. The messenger sense of the L segment contains one long single long open reading frame of 2151 amino acids, which encodes a deduced RNA dependent RNA polymerase of 246.4 kDa caculated molecular weight protein. The nucleotide sequence of the L segment of Howang strain shows 93%, 74%, 66%, 65% homology to HTNV 76/118, Seoul virus 80/39, Puumala virus $H{\ddot{a}}lln{\ddot{a}}s$ B1 and Sin Nombre virus, respectively. The amino acid sequence of the L segment of Howang strain shows 99%, 85%, 68%, 68% homology to HTNV 76/118, Seoul virus 80/39, Puumala virus $H{\ddot{a}}lln{\ddot{a}}s$ B1 and Sin Nombre virus, respectively.

• 대한치과교정학회지
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• 제50권5호
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• pp.324-335
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• 2020

Objective: To compare postoperative positional changes in the mandibular proximal segment between the conventional orthognathic surgery (CS) and the surgery-first approach (SF) using intraoral vertical ramus osteotomy (IVRO) in patients with Class III malocclusion. Methods: Thirty-eight patients with skeletal Class III malocclusion who underwent bimaxillary surgery were divided into two groups according to the use of preoperative orthodontic treatment: CS group (n = 18) and SF group (n = 20). Skeletal changes in both groups were measured using computed tomography before (T0), 2 days after (T1), and 1 year after (T2) the surgery. Three-dimensional (3D) angular changes in the mandibular proximal segment, condylar position, and maxillomandibular landmarks were assessed. Results: The mean amounts of mandibular setback and maxillary posterior impaction were similar in both groups. At T2, the posterior portion of the mandible moved upward in both groups. In the SF group, the anterior portion of the mandible moved upward by a mean distance of 0.9 ± 1.0 mm, which was statistically significant (p < 0.001). There were significant between-group differences in occlusal changes (p < 0.001) as well as in overjet and overbite. However, there were no significant between-group differences in proximal segment variables. Conclusions: Despite postoperative occlusal changes, positional changes in the mandibular proximal segment and the position of the condyles were similar between CS and SF, which suggested that SF using IVRO achieved satisfactory postoperative stability. If active physiotherapy is conducted, the proximal segment can be adapted in the physiological position regardless of the occlusal changes.

• Journal of Korean Neurosurgical Society
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• 제29권7호
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• pp.949-952
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• 2000

The incidence of superior cerebellar artery aneurysm is less than 1% of all intracranial aneurysms. These aneurysms usually occur at the junction between the superior cerebellar artery and the basilar trunk, however, seldom occur distally. We present a extremely rare case of distal superior cerebellar artery aneurysm arising at the junction between anterior pontine segment and ambient segment.

• 전자공학회논문지
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• 제54권1호
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• pp.139-146
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• 2017

ISDB-T(Integrated Service Digital Broadcasting Terrestrial)는 OFDM(Orthogonal Frequency Division Multiplexing) 기반의 전송기술 및 Time Interleaving 기술을 사용하고 있기 때문에 다중 경로 및 Impulse Noise에 대응 가능하며, 이동 수신 환경에서도 어느 정도 양호한 성능을 나타낸다. 원세그(One-Seg), 풀세그(Full-Seg)는 할당된 세그먼트 개수에 따라 구분하며, 원세그 수신기는 변복조 방법으로 QPSK(Quadrature Phase Shift Keying)를 사용하기 때문에 64QAM(64 Quadrature Amplitude Modulation)을 사용하는 풀세그 수신기와 비교하여 높은 기술력 없이도 구현 가능하지만, 영상 데이터율의 한계로 화면 사이즈와 해상도의 제한이 크다. 본 논문에서는 셋탑박스, 고정형 TV, 일체형 네비게이션 등에 적용 가능한 HD급 해상도를 지원하는 풀세그 ISDB-T 방송 수신 모듈을 설계하고 구현한다. 실험을 통해 개발된 풀세그 ISDB-T 방송 수신 모듈의 기능이 정상적으로 동작함을 확인하였다.

• 한국의류학회지
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• 제33권12호
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• pp.1862-1872
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• 2009

본 연구에서는 한국과 중국 대학생을 대상으로 의복쇼핑가치 유형을 밝히고 쇼핑가치 유형에 따라 한국과 중국의 대학생들의 의류점포속성 중요도에 차이가 있는지를 알아보고, 각 세분집단에서 한국과 중국에 대학생들에 따라 의류점포속성 중요도에 차이가 있는지를 알아보았다. 한국의 경우 고 관여 쇼핑 집단의 응답자들은 다른 집단들 보다 점포 분위기, 편의성, 판매원의 행동을 더 중요하게 생각하고 있었다. 반면 중국 소비자들의 경우 쾌락적 쇼핑 집단인 다른 집단들 보다 점포 분위기를 더 중요시 여기고 있었으며 고 관여 쇼핑 집단이 다른 집단들 보다 점포 분위기, 점포 서비스, 제품의 구색과 편의성을 더 중요하게 생각하고 있었다. 쾌락적 쇼핑 집단에서 한국 응답자들은 중국 응답자들 보다 서비스를 더 중요시 여기고 있었으며 중국의 응답자들은 점포의 편의성 더 한국의 응답자들보다 더 중요하게 생각하고 있었다. 저 관여 쇼핑 집단에서 한국의 응답자들은 중국의 응답자들보다 점포의 분위기와 서비스, 다양한 상품의 구색을 갖추고 있는지를 더 중요하게 생각하고 있었다. 고 관여 쇼핑 집단에서 한국의 응답자들은 중국의 응답자들보다 판매원의 행동 부분들을 더 중요하게 생각하고 있었으며 중국의 응답자들은 한국의 응답자들보다 점포의 거리와 같은 편리성 부분을 더 중요하게 생각하고 있었다. 실용 쇼핑 집단에서 한국의 응답자들이 중국의 응답자들보다 점포의 서비스, 상품구색, 판매원을 더 중요하게 생각하고 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1623-1625
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• 1998

At present, in case of circular conductor, various water blocking methods are in use for power cable. But, in case the shape of the conductor is sector shaped, segment conductor it was very difficult to make the water blocking segment conductor. This paper describes the developement details of the water blocking segment conductor applied with swellable powder.

• Structural Engineering and Mechanics
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• 제45권3호
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• pp.337-354
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• 2013

For shield TBM (Tunnel Boring Machine) tunnel lining, the segment joint is the most critical component for determining the mechanical response of the complete lining ring. To investigate the mechanical behavior of the segment joint in a water conveyance tunnel, which is different from the vehicle tunnel because of the external loads and the high internal water pressure during the tunnel's service life, full-scale joint tests were conducted. The main advantage of the joint tests over previous ones was the definiteness of the loads applied to the joints using a unique testing facility and the acquisition of the mechanical behavior of actual joints. Furthermore, based on the test results and the theoretical analysis, a mechanical model of segment joints has been proposed, which consists of all important influencing factors, including the elastic-plastic behavior of concrete, the pre-tightening force of the bolts and the deformations of all joint components, i.e., concrete blocks, bolts and cast iron panels. Finally, the proposed mechanical model of segment joints has been verified by the aforementioned full-scale joint tests.

• 대한수의학회지
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• 제32권3호
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• pp.333-339
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• 1992

The regional distribution and relative frequency of occurrence of endocrine cells in nine segments of the gastrointestinal(GI) tract of snakehead(Ophicephalus argus) were investigated by immunohistochemical methods using specific antisera against 5- hydroxyptrytamine(5-HT), somatostatin, gastrin/cholecystokinin(GAS/CCK), glucagon, bovine chromogranin, porcine chromogranin and insulin. Four types of immunoreactive cells for 5-HT, somatostatin, GAS/CCK and glucagon were observed in the GI tract. These cells were generally appeared in the mucosal epithelia or located at the interface of the mucosal epithelial layer and intestinal glandular region. 5-HT-immunoreactive(IR) cells were found in segment II, III, IV, V and VI, and the most numerous in segment IV. Somatostatin-IR cells were found in segment II, III, IV and V, and the most numerous in segment III. GAS/CCK-IR cells in segment VI, VII and glucagon-IR cells in segment III, IV, V were detected but a few in these segments. No bovine chromogranin-, porcine chromogranin- and insulin-IR cells were detected throughout the GI tract of the snakehead.

• 한국정보처리학회논문지
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• 제6권4호
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• pp.851-867
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• 1999

Numerous proposals for extending the relational data model as well as conceptual and object-oriented data models have been suggested. However, there has been relatively less research in the area of defining segmented storage structure and data migration strategies for temporal data. This paper presents the segmented storage structure in order to increment search performance and the two data migration strategies for segmented storage structure. this paper presents the two data migration strategies : the migration strategy by Time granularity, the migration strategy by LST-GET. In the migration strategy by Time Granularity, the dividing time point to assign the entity versions to the past segment, the current segment, and future segment is defined and the searching and moving process for data validity at a granularity level are described. In the migration strategy by LST-GET, we describe the process how to compute the value of dividing criterion. searching and moving processes are described for migration on the future segment and the current segment and entity versions 새 assign on each segment are defined. We simulate the search performance of the segmented storage structure in order to compare it with conventional storage structure in relational database system. And extensive simulation studies are performed in order to compare the search performance of the migration strategies with the segmented storage structure.