• 제목/요약/키워드: SSCs

검색결과 79건 처리시간 0.031초

1020개의 커넥션을 지원하는 AAL2 Voice gateway구현 (Implementation of AAL2 Voice gateway with 1020 connections)

  • 이요섭;이상길;최명렬
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2002년도 봄 학술발표논문집 Vol.29 No.1 (A)
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    • pp.226-228
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    • 2002
  • 이동통신망이 발달하면서 기존의 인프라를 생성하였던 ATM망을 음성서비스에 활용하기 위한 Voice over ATM기술이 많은 발전을 하고 있다. 본 논문에서는 ATM 망에서 Low-bit-rate voice 트래픽을 처리하기 위해 1020개의 커넥션을 지원하는 AAL2 Voice gateway를 구현하였다. 본 논문에서 구현된 AAL2 Voice gateway는 ITU-T Recommendations 1.363.2와 1.366.2에 근거하여 설계하였다. 또한, SSCS(Service Specific Convergence Sublayer)와 CPS(Common Part Sublayer) 부계층을 모두 하드웨어로 구현하였다. 본 AAL2 Voice gateway는 VHDL로 구현되었으며, 이동통신망과 VoDSL의 Voice gateway에서 그 효용 가치가 높을 것으로 사료된다.

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고유동 콘크리트의 투수성에 관한 연구 (Permeability of Self-Consolidating Concrete)

  • 김민석;최석환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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    • pp.156-159
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    • 2003
  • Large amount of binders and high-range AE water-reducing (HRWR) agent are required for self-consolidating concrete in order to achieve flowability and segregation resistance. In this study, the initial permeability of SSC(self-consolidating concrete) until the age of 28 days is measured and compared with those of other SSCs, in which some parts of cement are substituted with fly ash or blast furnace slag. The strengths of SSC samples are also examined along with the permeability change.

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Isolation and Identification of Prepubertal Buffalo (Bubalus bubalis) Spermatogonial Stem Cells

  • Feng, Wanyou;Chen, Shibei;Do, Dagiang;Liu, Qinyou;Deng, Yanfei;Lei, Xiaocan;Luo, Chan;Huang, Ben;Shi, Deshun
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권10호
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    • pp.1407-1415
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    • 2016
  • Isolation and culture of spermatogonial stem cells (SSCs) are attractive for production of genetic modified offspring. In the present study, buffalo spermatogonial stem-like cells were isolated, cultured and expression pattern of different germ cell marker genes were determined. To recover spermatogonia, testes from age 3 to 7 months of buffalo were decapsulated, and seminiferous tubules were enzymatically dissociated. Two types of cells, immature sertoli cell and type A spermatogonia were observed in buffalo testes in this stage. Germ cell marker genes, OCT3/4 (Pou5f1), THY-1, c-kit, PGP9.5 (UCHL-1) and Dolichos biflorus agglutinin, were determined to be expressed both in mRNA and protein level by reverse transcription polymerase chain reaction and immunostaining in buffalo testes and buffalo spermatogonial stem-like cells, respectively. In the following, when the isolated buffalo buffalo spermatogonial stem-like cells were cultured in the medium supplemented 2.5% fetal bovine serum and 40 ng/mL glial cell-derived neurotrophic factor medium, SSCs proliferation efficiency and colony number were significantly improved than those of other groups (p<0.05). These findings may help in isolation and establishing long term in vitro culture system for buffalo spermatogonial stem-like cells, and accelerating the generation of genetic modified buffaloes.

Topical anesthesia for stainless steel crown tooth preparation in primary molars: a pilot study

  • Padminee, Krishnan;Hemalatha, R;Shankar, P;Senthil, D;Trophimus, Gnanabagyan J
    • Journal of Dental Anesthesia and Pain Medicine
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    • 제20권4호
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    • pp.241-250
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    • 2020
  • Background: Placement of full-coverage restorations such as stainless steel crowns (SSCs) for pulpectomy treated primary molars is essential for successful outcomes. The tooth preparation process for SSCs can cause discomfort to gingival tissues since the crown should be seated 1 mm subgingivally. The purpose of this prospective trial was to compare the effectiveness of subgingival and transmucosal application of topical anesthetics on dental pain during SSC tooth preparation among 6- to 8-year-old children. Methods: A consecutive sample of 27 children, aged 6-8 years, who required an SSC after pulp therapy in primary molars were randomly divided into three groups. Group A received infiltration anesthesia before tooth preparation for SSC placement, whereas in Group B and C, only topical anesthesia was applied subgingivally and transmucosally. Wong-Bakers Faces pain rating scale (WBFPS) scores were recorded after tooth preparation. Faces, Legs, Activity, Cry and Consolability (FLACC) scores were evaluated by two blinded and calibrated investigators through video recordings of the patient during tooth preparation. Data were tabulated, and inter-group comparisons were performed using the Kruskal-Wallis and analysis of variance tests. Results: Out of the 27 participants, 48% were boys and 52% were girls, with an overall mean age of 6.83 years. Group A showed the least pain scores according to both the scales, followed by Group B and Group C. The pain intensity was statistically significant on both the pain scales with P = 0.003 for FLACC and P < 0.001 for WBFPS. Conclusion: Subgingival application of topical anesthesia reduced pain to a certain extent but not as effectively as infiltration anesthesia during SSC tooth preparation in primary molars. Transmucosal application of topical anesthesia did not reduce discomfort when compared to the other two interventions.

A morphometric study on stainless steel crowns of the primary first molar using a three dimensional scanner

  • Lee, Jihyun;Shin, Teo Jeon;Kim, Young-Jae;Kim, Jung-Wook;Jang, Ki-Taeg;Lee, Sang-Hoon;Kim, Chong-Chul;Hyun, Hong-Keun
    • 대한치과의사협회지
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    • 제54권6호
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    • pp.414-428
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    • 2016
  • Objectives: The aim of this study was to assess the morphologic characteristics of two types of stainless steel crowns (SSCs) for the first primary molar using a 3D scanner. Study design: Two types of SSCs, KIDS CROWN (KC) and 3M ESPE ND-96 (ND), for the first primary molars were scanned using a 3D scanner. The mesiodistal and buccolingual diameters at the height of the contour and the cervical margin, occlusocervical diameters on the mesial, distal, buccal, and lingual aspects were measured, and the crown shape ratio, the smooth surface crown height ratio, and the cervical convergence were calculated. Results: In the crown shape ratio of the mandibular SSC, KC was larger buccolingually compared with ND. In the smooth surface crown height ratio, ND was larger than KC in all of the maxilla and mesial, distal, and lingual aspects of the mandible. ND was more convergent to the cervical mesiodistally and buccolingually compared with KC. Conclusion: In the superimposed images of the maxillary SSC, the mesiolingual and distolingual line angles of KC were more prominent compared with ND. In the mandible, ND demonstrated higher cusps and more obvious buccal developmental lobes than KC. ND showed a larger cervical undercut than KC.

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YY1 and CP2c in Unidirectional Spermatogenesis and Stemness

  • Cheon, Yong-Pil;Choi, Donchan;Lee, Sung-Ho;Kim, Chul Geun
    • 한국발생생물학회지:발생과생식
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    • 제24권4호
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    • pp.249-261
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    • 2020
  • Spermatogonial stem cells (SSCs) have stemness characteristics, including germ cell-specific imprints that allow them to form gametes. Spermatogenesis involves changes in gene expression such as a transition from expression of somatic to germ cell-specific genes, global repression of gene expression, meiotic sex chromosome inactivation, highly condensed packing of the nucleus with protamines, and morphogenesis. These step-by-step processes finally generate spermatozoa that are fertilization competent. Dynamic epigenetic modifications also confer totipotency to germ cells after fertilization. Primordial germ cells (PGCs) in embryos do not enter meiosis, remain in the proliferative stage, and are referred to as gonocytes, before entering quiescence. Gonocytes develop into SSCs at about 6 days after birth in rodents. Although chromatin structural modification by Polycomb is essential for gene silencing in mammals, and epigenetic changes are critical in spermatogenesis, a comprehensive understanding of transcriptional regulation is lacking. Recently, we evaluated the expression profiles of Yin Yang 1 (YY1) and CP2c in the gonads of E14.5 and 12-week-old mice. YY1 localizes at the nucleus and/or cytoplasm at specific stages of spermatogenesis, possibly by interaction with CP2c and YY1-interacting transcription factor. In the present article, we discuss the possible roles of YY1 and CP2c in spermatogenesis and stemness based on our results and a review of the relevant literature.

XTI/ATM 환경에서의 멀티미디어 통신을 위한 VGC 기반의 SRTS/AAL-2 연구 (A Study on the SRTS/AAL-2 based on VGC for Multimedia Communication using XTI/ATM)

  • 신동진;김영탁
    • 한국멀티미디어학회:학술대회논문집
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    • 한국멀티미디어학회 1998년도 춘계학술발표논문집
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    • pp.333-338
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    • 1998
  • 본 논문에서는 AAL-2/ATM 통신망 환경에서 멀티미디어 통신을 구현하기 위한 멀티미디어 동기화 기능으로 VGC 기반의 SRTS/AAL-2를 제안한다. 제안된 멀티미디어 동기화 알고리즘에서는 가변 비트율 멀티미디어 정보의 클럭 주파수 복원을 위하여 VGC(Virtual Global Clock)을 구성하고, 이를 기반으로 한 SRTS방식의 미디어 내부 동기와, MM-SSCFS(Multimedia-SSCS)/AAL-2 프로토콜을 사용한 미디어 간의 동기를 유지하는 방법을 제안하였다. 본 논문의 실험 환경으로는 Fore ATM 교환기(155 Mbps $\times$8 port)를 사용해서 소규모 B-ISDN/ATM 통신망을 구성하였고, SUN Workstatin Solaris 2.5에 접속된 Fore ATM 접속 카드 SBA-200에서 지원하는 XTI(X/Opne Transport Interface)-API를 사용하였다.

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ATM-PON의 AAL2에서 서비스 유형별 부호화 방안의 성능 (Performance of Coding Scheme for Various Service Types in AAL2 of ATM-PON)

  • 김우태;배상재;허재두;주언경
    • 한국통신학회논문지
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    • 제27권11C호
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    • pp.1033-1039
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    • 2002
  • 본 논문에서는 ATM-PON의 AAL2에서의 서비스 유형에 맞는 적절한 부호화 방안을 제시하였다. AAL2 계층의 SSCS 중 SSTED에 있는 6개의 예비용 비트 중 2비트를 이용하여 서비스 유형과 각 유형에 적합한 오류정정 부호의 사용 여부를 구별한다. 그리고 BCH와 길쌈부호를 포함하여 서비스의 유형별로 적합한 부호화 방안을 같은 부호화 방식을 사용하는 경우와 다른 부호화 방식을 사용하는 경우로 나누어서 각각에 대해 성능을 분석하였다. 이러한 부호화 방안들 중에서 음성인 경우에는 (127,120) BCH부호를, 그리고 데이터인 경우에는 (127,113) BCH부호를 사용하는 것이 가장 적절할 것으로 사료된다.

건설원전 형상관리를 위한 통합변경프로세스 연구 (Research Integrated Change Process for Configuration Management of Construction Nuclear Power Plant)

  • 박유진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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    • pp.231-232
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    • 2016
  • Configuration Management (CM) is a process of identifying and documenting the characteristics of a Structures, Systems and Components (SSCs), and of ensuring that changes to these characteristics are properly assessed, approved, issued, implemented and verified. There are requirement management, change control, facility configuration information management for CM activities. In order to improve safety of Nuclear Power Plant(NPP), it is necessary to manage change item systematically. Existing CM concept is focused on the NPP in operation. On the other hand, NPP under construction is difficult to efficiently manage the change because of different change process from varoius stake-holders. This research considers method of consolidation change process for NPP to ensure that approved changes are accurately reflected in the design requirements, facility configuration information, and the physical configuration.

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Shared Service Center 도입을 통한 지원 기능 역량 강화 방안 (Build Up Support Function Capability by Introduction of Shared Service Center)

  • 주민우;최성락;박기한;윤형제
    • 한국IT서비스학회:학술대회논문집
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    • 한국IT서비스학회 2005년도 춘계학술대회
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    • pp.575-579
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    • 2005
  • A Shared Services center (SSC) is created by removing common administrative functions from operational divisions within an organization, and centralizing the functions in a separate centre. SSC helps supporting organizations to focus on core activities and to achieve cost reduction as well as service quality enhancement. In contrast to many leading global companies which has been adopted SSCs from early 90's. A Company's HR SSC which has opened this year is the first genuine SSC practice in Korea. Centering on the case of A Company' s HR SSC implementation, we discussed on some practical implications for companies which has future plan to introduce a shared service center.

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