• 제목/요약/키워드: Gap times

검색결과 1,024건 처리시간 0.032초

갭 슬리블 구조를 갖는 DTV 실내 수신용 안테나의 구현 (Implementation of DTV Indoor Receiving Antenna with Gap Sleeve Structure)

  • 강상원;장대순;이윤민
    • 한국인터넷방송통신학회논문지
    • /
    • 제16권2호
    • /
    • pp.145-150
    • /
    • 2016
  • 본 논문은 갭 슬리브 모노폴 구조를 갖는 DTV 실내 수신용 안테나를 제안하였다. 제안한 안테나는 슬리브 모노폴 기본 구조와 갭 슬리브를 이용하였다. 안테나를 최적화 하기위해 복사기와 슬리브 사이 갭 조정, 슬리브와 그라 운드 사이 갭을 조정하였다. 안테나 파라미터 특성을 확인하기 위해 ANSYS사의 HFSS를 이용하였다. 안테나 제작을 위해 비유전율이 4.7인 FR4 유전체 기판을 사용하였다. 안테나의 크기는 $213{\times}40{\times}1.6mm$이다. 제작된 안테나의 주파 수대역은 432MHz~827MHz이고, 대역폭은 395MHz이다. 최대 안테나 이득은 2.19dBi이다. 시뮬레이션과 측정 데이터 를 비교분석한 결과 간격 슬리브 구조를 갖는 DTV 실내 수신용 안테나의 실용화 가능성을 확인할 수 있었다.

랫드 유선 상피 세포의 분리와 gap junction 단백질의 발현 양상 (Characterization of rat mammary epithalial cells and expression of gap junctional proteins)

  • 서민수;강경선;이영순
    • 대한수의학회지
    • /
    • 제43권4호
    • /
    • pp.649-656
    • /
    • 2003
  • We have a cultured method to grow rat mammary epithelial cells (RMEC) for 1 to 14 days in 1:1 mixture of Dulbecco's Modified Eagle Medium: Nutrient and F-12 (DMEM/F-12) containing 10% fetal bovine serum (FBS), human EGF, insulin, hydrocortisone, human transferrin and $17{\beta}$-estradiol in vitro. We were able to isolate and distinguish two cell types, luminal epithelial cells and myoepithelial cells, from primary clutures of RMEC. Immunocytochemical stains were used to distingusih luminal epithelial cells and myoepithelial cells. Peanut lectin (PNA) was stained in most alveolar epithelail cells and luminal epithelial cells of rats, while Thy-1.1, a maker of potential rat mammary myoepithelial cells, was expressed in myoepithelial cells in the rat. Also, we examined the expression patterns of three types of gap junction proteins, connexin 26 ($C{\times}26$), connexins 32 ($C{\times}32$) and connexin 43 ($C{\times}43$) by immunocytochemistry and western blot analysis. In the cell types, the results show that at the early stage of culture, luminal epithelial cells were increased and these cells were surrounded by myoepithelial cells. At the late stage of culture, luminal epithelial cells were decreased, in contrast myoepithelial cells were increased. In the expression pattern of gap junction, $C{\times}26$ maintained it's expression until day 3, but afterwards gradually decreased in intensity. Expression of $C{\times}32$ remained until day 5, then decreased slightly. $C{\times}43$ gradually increased untill the middle time of culture then decreased in intensity. These results suggest that connexins may be important for the control of growth in rat mammary epithelial cell types.

ON THE SEVERAL DIFFERENCES BETWEEN PRIMES

  • Park, Yeonyong;Lee, Heonsoo
    • Journal of applied mathematics & informatics
    • /
    • 제13권1_2호
    • /
    • pp.37-51
    • /
    • 2003
  • Enumeration of the primes with difference 4 between consecutive primes, is counted up to 5${\times}$10$\^$10/, yielding the counting function ,r2,4(5${\times}$10$\^$10/) = l18905303. The sum of reciprocals of primes with gap 4 between consecutive primes is computed B$_4$(5 ${\times}$ 10$\^$10/) = 1.1970s4473029 and B$_4$ = 1.197054 ${\pm}$ 7 ${\times}$ 10$\^$-6/. And Enumeration of the primes with difference 6 between consecutive primes, is counted up to 5${\times}$10$\^$10/, yielding the counting function $\pi$$\_$2.6/(5${\times}$10$\^$10/) = 215868063. The sum of reciprocals of primes with gap 6 between consecutive primes is computed B$\_$6/(5${\times}$10$\^$10/) = 0.93087506039231 and B$\_$6/ = 1.135835 ${\pm}$ 1.2${\times}$10$\^$-6/.

Development of a Simplified Fuel-Cladding Gap Conductance Model for Nuclear Feedback Calculation in 16$\times$16 FA

  • Yoo, Jong-Sung;Park, Chan-Oh;Park, Yong-Soo
    • 한국원자력학회:학술대회논문집
    • /
    • 한국원자력학회 1995년도 추계학술발표회논문집(2)
    • /
    • pp.636-643
    • /
    • 1995
  • The accurate determination of the fuel-cladding gap conductance as functions of rod burnup and power level may be a key to the design and safety analysis of a reactor. The incorporation of a sophisticated gap conductance model into nuclear design code for computing thermal hydraulic feedback effect has not been implemented mainly because of computational inefficiency due to complicated behavior of gap conductance. To avoid the time-consuming iteration scheme, simplification of the gap conductance model is done for the current design model. The simplified model considers only the heat conductance contribution to the gap conductance. The simplification is made possible by direct consideration of the gas conductivity depending on the composition of constituent gases in the gap and the fuel-cladding gap size from computer simulation of representative power histories. The simplified gap conductance model is applied to the various fuel power histories and the predicted gap conductances are found to agree well with the results of the design model.

  • PDF

곱모형에 의한 외식업 서비스품질 5차원이 고객만족도, 재방문의도 및 고객애호도에 미치는 영향 (A study on the effects of DINESERV's 5-dimensions by multiply-model on satisfaction, revisit intention and customer loyalty)

  • 조윤식
    • Journal of the Korean Data and Information Science Society
    • /
    • 제20권2호
    • /
    • pp.273-281
    • /
    • 2009
  • 갭모형은 구매전 기대와 구매후 성과 사이의 차이가 고객만족도와 같은 종속변수에 대한 영향을 이해하려는 기대불일치 패러다임에 근거한 것이다. 이러한 패러다임과는 달리 Bhote는 갭모형 대신에 곱모형을 제안하였다. 곱모형은 구매전 중요도와 구매후 성과를 곱하여 구하는 고객만족도지수에 근거한 것이다. 본 연구는 Bhote의 곱모형을 외식업에 적용한 것이다. 본 연구의 목적은 곱모형에 의한 외식업의 서비스품질의 5차원이 고객만족도, 재방문의도, 및 고객애호도를 설명하는 모형의 독립변수로 적합한지의 여부를 검정하는 것이다. 모형검정을 위해 회귀분석의 F-값이 활용되었다. 분석결과 곱모형은 적합한 것으로 나타났다.

  • PDF

MR Damper의 Gap Size에 따른 제어성능 분석 (Analysis of Control Performance in Gap Size of MR Damper)

  • 허광희;전승곤;서상구;김대혁
    • 한국구조물진단유지관리공학회 논문집
    • /
    • 제25권1호
    • /
    • pp.41-50
    • /
    • 2021
  • 본 연구에서는 MR Damper의 제어력을 결정하는 다양한 요인들 중, 유로폭(Gap Size)을 다르게 선정하여 그에 따른 제어력의 변화를 확인하였다. 이를 위해 Gap Size 1.0mm, 1.5mm인 MR Damper 두 대를 제작하고 인가전류와 가진조건을 정하였으며 그에 따른 동하중 실험을 수행하였다. 실험결과 최소제어력은 Gap Size 1.0mm 조건이 Gap Size 1.5mm 조건보다 3.2배 높았으며 최대제어력은 Gap Size 1.0mm 조건이 Gap Size 1.5mm 조건보다 2.3배 높았다. 또한, 인가전류에 따른 제어력의 증가폭은 Gap Size 1.0mm일 때 34N, Gap Size 1.5mm일 때 12.7N으로 나타났다. Gap Size가 커질수록 전체 제어력과 인가전류에 따른 제어력의 증가는 감소하였다. 두 개의 MR Damper의 동적범위를 확인해 본 결과 Gap Size 1.0mm일 때 평균 2.3, Gap Size 1.5mm일 때 평균 2.8인 것을 볼 때 두 MR Damper의 준능동제어장치로써 사용가능성을 확인하였다.

청소년 자녀의 건강관련 삶의 질에 대한 부모와 자녀의 인식차이가 청소년 우울에 미치는 영향 (Correlates of Depression and Perception Gap of Adolescents' Health-Related Quality of Life between Parents and Children)

  • 김정현;천성수
    • 한국학교ㆍ지역보건교육학회지
    • /
    • 제17권2호
    • /
    • pp.1-16
    • /
    • 2016
  • Objectives: The objective of this study is to evaluate the correlates of depression and perception gap of adolescents' Health-Related Quality of Life (HRQOL) between Parents and Children. Methods: Research targets are all students and their parents who are enrolled in from 1st~3rd grade of middle school to $1^{st}$ grade of high school which was selected intentionally. The survey was conducted from May $16^{th}$ to June $9^{th}$ in 2014 by research staffs equipped with structured questionnaire. $PedsQL^{TM}4.0$ Generic Core Scales and Korean form of the Kovacs' Children's Depression Inventory were the main tool for measuring the HRQOL and depression. Data of 985 respondents, both of parents and children, was used for analysis of this study. Results: In terms of gender difference of depression, 5.8% of adolescents, 3.2% of male and 8.5% of female (p<0.001), are shown depression symptom. Depression rate of the low level students of academic achievement was 11.0% which is the lowest rate to compare to 4.3% of middle level and 2.6% of high level students (p<0.001). The case that parents overestimated their children's overall HRQOL is 3.699 times more likely to have depression symptom than the case which is in concurrence between parents and children. Especially the overestimation in social, emotional, and academic area of HRQOL promote depression 3.918 times, 3.371 times, and 2.258 times more than the agreement occurred of each areas. In contrast underestimation in physical area of HRQOL reduce depression 0.266 times less than the agreement occurred of the area. Conclusion: The perception gap of adolescents' HRQOL between parents and children is the most influential factor to adolescents' depression among all variables which was evaluated in this study.

Optimum Air-Gap Flux Distribution with Third Harmonic Rotor Flux Orientation Adjustment for Five-Phase Induction Motor

  • Kang, Min;Yu, Wenjuan;Wang, Zhengyu;Kong, Wubin;Xiao, Ye
    • Journal of Electrical Engineering and Technology
    • /
    • 제13권1호
    • /
    • pp.315-325
    • /
    • 2018
  • This paper investigates optimum air-gap flux distribution with third harmonic rotor flux orientation adjustment for five-phase induction motor. The technique of objective is to generate a nearly rectangular air-gap flux, and it improves iron utilization under variation loading conditions. The proportional relations between third harmonic and fundamental plane currents is usually adopted in the conventional method. However, misalignment between fundamental and third harmonic component occurs with variation loading. The iron of stator teeth is saturated due to this misalignment. This problem is solved by third harmonic rotor flux orientation adjustment simultaneously, and direction and amplitude are changed with mechanical load variation. The proposed method ensures that the air-gap flux density is near rectangular for a maximum value from no load to rated load. It is confirmed that the proposed method guarantees complete both planes decoupling with third harmonic flux orientation adjustment. The effectiveness of the proposed technique is validated experimentally.

유체압력(流體壓力)에 의한 Squeezed O-ring의 압착(壓着)과 초기(初期) 압출(押出) Mechanism (Pressurization and Initial Extrusion of a Squeezed O-Ring into a Clearance Gap)

  • 김원호
    • Elastomers and Composites
    • /
    • 제30권3호
    • /
    • pp.235-246
    • /
    • 1995
  • When an O-ring is installed in a high fluid pressure device, a section of the O-ring is extruded into the piston-cylinder clearance gap. Any tendency towards extrusion will induce wear in dynamic applications, leading to premature failure of the seal. In this study, the mechanism of initial extrusion of the O-ring was studied, 1.e., how much amount of the O-ring will be extruded into the clearance gap at a certain pressure. The relationship between extrusion depth and a clearance gap or fluid pressure were studied by finite element analysis (FEA). After that, Salita's experimental data were analyzed. The result is that Initial extrusion depth for an O-ring into a clearance gap was 1.11 times the product of dimensionless pressure difference $(p-p_1)/E$ and clearance gap c. The required pressure $p_1$ for zero extrusion depth was found to decrease logarithmically with increasing clearance gap.

  • PDF

접착형 2급 주조 금 인레이의 치은변연 접합도에 관한 연구 (A GINGIVAL MARGINAL FIT OF THE ADHESIVE CLASS II CAST GOLD INLAY)

  • 최희경;신동훈;홍찬의
    • Restorative Dentistry and Endodontics
    • /
    • 제19권2호
    • /
    • pp.473-484
    • /
    • 1994
  • To investigate the effect of resin cement, which had been known to increase the adhesive capacity of the cast gold inlay, on the gingival marginal fit and whether the tin-planting of the beveled area affects the marginal fit, Class II cast gold inlays were made on the 25 sound molars. Control group(ZPC goup) was cemented with the ZPC by conventional method. Experimental groups were cemented with the resin cement(Super-hond & $Panavia_{EX}$) and subdivided further by the existence or nonexistence of the tin-plating of the beveled area(ST & PT groups: with plating, SNT & PNT groups: without plating). So, each group was consisted of 5 teeth and the gingival margin of each specimen was mesiodistally sectioned by 3 times and the marginal and internal gap were evaluated by the Stereo Microscope (${\times}180$) and the Scanning Electron Micrascope(${\times}5,000$) was used for examining the adhesive relationship of the resin cement to the cavity wall and to the cast gold surface. The results were as follows : 1. Marginal gap was less than internal gap in all groups. 2. ZPC and SNT(bevel without tin-plating) groups showed the least gap and gap in PNT(bevel without tin-plating) group, ST(bevel with tin-plating) group, PT(bevel with tin-plating) group showed the greater value in order in evaluation of the both internal gap and marginal gap. 3. With the exception of the relationships between ZPC and SNT groups, ST and PNT groups, relationships between any other groups showed the statistical significance in the internal gap(p<0.05). 4. In the marginal gap, all relationships between groups showed the statistical significance (p<0.05) except the relationships between ZPC and SNT groups, ST and PNT groups, ZPC and PNT groups. 5. ZPC group showed more soluble phenamena than the resin groups(ST, SNT, PT, PNT). 6. Resin cement showed the void spaces in spite of good penetration into the micro-irregularities on both the tooth surface and the cast surface. The void was shown more in PT and PNT groups than in the ST and SNT groups. 7. After the treatment of heat and desiccation for SEM specimen, resin cements were detached more easily from the tooth surface than from the cast surface.

  • PDF