• 제목/요약/키워드: S.V

검색결과 14,795건 처리시간 0.045초

Pressure Chamber Technique에 의한 대두경엽의 수분특성 연구 (A Study on the Water Relation Characteristics of the Soybean Shoots through the Pressure Chamber Technique)

  • 김이훈
    • 한국작물학회지
    • /
    • 제28권1호
    • /
    • pp.128-132
    • /
    • 1983
  • Pressure chamber(DIC-PC-40형) technique에 의한 대두재배품종 Williams와 금강대립의 경엽에 대한 수분특성의 결과는 다음과 같다. 1. 최대포수시의 삼투압$(\Pi_p)$은 Williams 9.0bar, 금강대립은 10.4bar였다. 3. 초기원형질분리점에서의 상대함수율$(PWC^*)4은 금강대립이 86.0%, Williams가 92.6%였다. 4. 삼투수의 총량에 대한 원형질분리점에서의 침출량비$(V_p/V_o)$는 Williams가 94.0%, 금강대립이 83.4%였다. 5. 최대함수량에 대한 삼투수의 총량의 비$(V_p/w_5)$는 금강대립이 84.3%, Williams가 77.5%였다. 7. 탄성계수는 금강대립이 $1.6\times10^5bar$ 이었으며 Williams는 $8.5$\times$10^2$bar로 현저한 차이를 보였다.

  • PDF

Optical Properties of SnS2 Single Crystals

  • Lee Choong-Il
    • 한국재료학회지
    • /
    • 제15권3호
    • /
    • pp.195-201
    • /
    • 2005
  • The $SnS_2,\;SnS_2:Cd$, and $SnS_2:Sb$ single crystals were grown by the chemical transport reaction method. The indirect optical energy band gap was found to be 2.348, 2.345, and 2.343 eV for the $SnS_2,\;SnS_2:Cd$, and $SnS_2:Sb$ single crystals, at 6 K respectively. The direct optical energy band gap was found to be 2.511, 2.505, and 2.503 eV f3r the $SnS_2,\;SnS_2:Cd$, and $SnS_2:Sb$ single crystals, at 6 K respectively The temperature dependence of the optical energy band gap was well fitted by the Varshni equation. Two photoluminescence emission peaks with the peak energy of 2.214 and 1.792 eV for $SnS_2$, 2.214 and 1.837 eV for $SnS_2:Cd$, and 2.214 and 1.818 eV the $SnS_2:Sb$ were observed. The emission peaks were described as originating from the donor-acceptor pair recombinations.

Properties of Photoluminescience for AgInS2/GaAs Epilayer Grown by Hot Wall Epitaxy

  • Lee, Sang-Youl;Hong, Kwang-Joon
    • Transactions on Electrical and Electronic Materials
    • /
    • 제5권2호
    • /
    • pp.50-54
    • /
    • 2004
  • The AgInS$_2$epilayers with chalcopyrite structure grown by using a hot-wall epitaxy (HWE) method have been confirmed to be a high quality crystal. From the optical absorption measurement, the temperature dependence of the energy band gap on the AgInS$_2$/GaAs was derived as the Varshni's relation of E$\_$g/(T) = 2.1365 eV - (9.89${\times}$10$\^$-3/ eV/K) T$^2$/(2930+T eV). After the as-grown AgInS$_2$/GaAs was annealed in Ag-, S-. and In-atmosphere, the origin of point defects of the AgInS$_2$/GaAs has been investigated by using the photoluminescence (PL) at 10 K. The native defects of $V_{Ag}$, $V_s$, $Ag_{int}$, and $S_{int}$ obtained from PL measurement were classified to donors or accepters type. And, we concluded that the heat-treatment in the S- atmosphere converted the AgInS$_2$/GaAs to optical p-type. Also, we confirmed that the In in the AgInS$_2$/GaAs did not form the native defects because the In in AgInS$_2$did exist as the form of stable bonds.

액상화 취약심도를 고려한 지반정보에 따른 액상화 평가의 변화 (Liquefaction Assessment Variations with Regard to the Geotechnical Information Considering of Critical Depth for Liquefaction)

  • 송성완;김한샘;조완제
    • 한국지반환경공학회 논문집
    • /
    • 제21권6호
    • /
    • pp.5-11
    • /
    • 2020
  • 최근 포항 및 주변 지역에서 지진 발생에 따른 액상화 현상 관측으로 인해 액상화 발생 가능성을 예측하는 연구의 중요성이 대두되고 있다. 액상화 발생 가능성은 지반정보를 활용하여 평가할 수 있는데 평가에 활용되는 전단저항강도비(CRR)값은 두 가지 지반정보인 SPT-N값과 Vs값을 활용하여 결정할 수 있다. 이 두 가지 지반정보를 활용하여 평가한 액상화 발생 가능성의 정확도를 비교하는 연구가 수행된 바 있으며 해당 연구에서는 SPT-N값을 활용한 결과가 Vs값을 활용한 결과보다 정확하다는 결론을 지었다. 또한 Vs값을 활용한 결과의 정확도가 낮은 이유는 Vs값이 액상화에 취약한 심도를 고려하지 않고 일률적으로 12m 심도에서 측정되었기 때문인 것으로 판단하였다. 따라서 본 연구에서는 일률적으로 12m 지점에서 측정된 지반정보의 타당성을 확인하고자 액상화에 취약한 심도에서 측정된 SPT-N값을 Vs값으로 환산하는 총 10가지의 경험식을 활용하여 환산된 Vs값을 통해 액상화 발생 가능성을 평가하고 실제 액상화 발생 결과와 비교하여 정확도를 확인하는 작업을 수행하였다. 그 결과 액상화에 취약한 심도를 고려한 10가지 경우 중 7가지 경우에 대하여 고려하지 않은 결과에 비해 정확도가 높게 나타났다.

한냉에 노출된 인체의 냉각과 총지방량 및 S/V 비율 사이의 관계 (Relationship between Total Body Fat and S/V Ratio and Body Cooling for Two Hours at $15^{\circ}C$)

  • 정관옥;남기용
    • The Korean Journal of Physiology
    • /
    • 제3권1호
    • /
    • pp.19-28
    • /
    • 1969
  • Skin temperatures on 10 sites and rectal temperature at every 10 minutes, oxygen consumption at every 20 minutes were measured on 18 male subjects (ages between 14 and 47 years) after exposure to cold air at $15^{\circ}C$ for two hours in a climatic room. Total body fat measured by means of a skinfold method and ratio of body surface area (S) to body volume (V), S/V, were utilized as basis of observations. Surface area was calculated after DuBois equation and body volume was calculated by our original formula. In influencing on the heat loss from the body core to the cold environment, % fat showed inverse relations, whereas, S/V ratio showed direct relations. Thus these two factors acted antagonistically on the body heat loss. Local skin temperatures showed negative correlations with skinfold thickness on the same site, nemaly, on chest, r=-.567; on back, r=-.507; and on upper arm, r=-.353. The other 7 skin sites showed low correlations with % fat. Minimum mean weighted skin temperature (MWST) showed a negative correlation (r=-.443) with % fat, and showed no correlation with S/V ratio. Oxygen consumption in the cold air at $15^{\circ}C$ increased from the first measurement at 20 minutes after exposure and maintained the same increasing trend up to 120 minutes. ${\Delta}T_R$ was greater in tile lean subjects who showed a greater % change in oxygen consumption. The antagonistic actions of % fat and S/V ratio on the heat loss were manifested by observations as follows: minimum rectal temperature was higher In fat subjects (r=.600) and lower in subjects with a greater S/V ratio (=-.582), ${\Delta}T_R$ was smaller in fat subjects (r=-.738) and greater in subjects with a greater S/V ratio (r=.618). Temperature difference between body core and skin surface (minimum rectal temperature minus minimum MWST) showed a positive correlation with % fat (r=.600) and a negative correlation with S/V ratio (r=-.881). Decrease in the mean body temperature and heat debt, respectively, showed negative correlations with % fat and positive correlations with S/V ratio.

  • PDF

A NEW VERTEX-COLORING EDGE-WEIGHTING OF COMPLETE GRAPHS

  • Farahani, Mohammad Reza
    • Journal of applied mathematics & informatics
    • /
    • 제32권1_2호
    • /
    • pp.1-6
    • /
    • 2014
  • Let G = (V ; E) be a simple undirected graph without loops and multiple edges, the vertex and edge sets of it are represented by V = V (G) and E = E(G), respectively. A weighting w of the edges of a graph G induces a coloring of the vertices of G where the color of vertex v, denoted $S_v:={\Sigma}_{e{\ni}v}\;w(e)$. A k-edge-weighting of a graph G is an assignment of an integer weight, w(e) ${\in}${1,2,...,k} to each edge e, such that two vertex-color $S_v$, $S_u$ be distinct for every edge uv. In this paper we determine an exact 3-edge-weighting of complete graphs $k_{3q+1}\;{\forall}_q\;{\in}\;{\mathbb{N}}$. Several open questions are also included.

765kV 변전소 시운전에 관한 고찰 (Consideration on the trial operation of 765kV substation)

  • 변강;정시환;박근원;이상면;최만식
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
    • /
    • pp.29-31
    • /
    • 2002
  • Purpose of the 765kV trial operation conducted for the first time in our country are performance verification of domestic developed equipment(765kV M.Tr, GIS,etc) and extraction of problem in advance to commercial operation and cultivation of operation ability. The trial operation of 765kV substation was finished successfully under the positive supports of institutes. manufactures. and constructers. It is expected that extraction of problems in advance and accumulation of operation techniques through the trial operation of 765kV substation will be contributed largly to the realization of the without a hitch operation of 765kV system.

  • PDF

광통신 III-V/Si 레이저 다이오드 기술 동향 (III-V/Si Optical Communication Laser Diode Technology)

  • 김호성;김덕준;김동철;고영호;김갑중;안신모;한원석
    • 전자통신동향분석
    • /
    • 제36권3호
    • /
    • pp.23-33
    • /
    • 2021
  • Two main technologies of III-V/Si laser diode for optical communication, direct epitaxial growth, and wafer bonding were studied. Until now, the wafer bonding has been vigorously studied and seems promising for the ideal III-V/Si laser. However, the wafer bonding process is still complicated and has a limit of mass production. The development of a concise and innovative integration method for silicon photonics is urgent. In the future, the demand for high-speed data processing and energy saving, as well as ultra-high density integration, will increase. Therefore, the study for the hetero-junction, which is that the III-V compound semiconductor is directly grown on Si semiconductor can overcome the current limitations and may be the goal for the ideal III-V/Si laser diode.

좌상공정맥을 합병한 복합심혈관기형의 병리해부와 수술 성적: 16례 보 (Patho-anatomy and treatment of complex congenital cardiovascular anomalies associated with left superior vena cava: report of 16 cases)

  • 정원상
    • Journal of Chest Surgery
    • /
    • 제17권2호
    • /
    • pp.177-183
    • /
    • 1984
  • From July 1975 to March 1984, 16 patients of complex congenital cardiovascular anomalies associated with left superior vena cava were seen at Han-Yang University Hospital. The age of patients was ranged from 2 to 15 years-old. The distribution of Sex was 7 patients in male, 9 patients in female. Persistent Left Superior Vena Cava [L.S.V.C.] was classified according to the proximal connection of L.S.V.C. into 3 groups. Group I which L.S.V.C. connected to coronary venous sinus was in 9 patients, Group II which L.S.V.C. connected to Left atrium was in 5 patients, Group III which L.S.V.C. hemodynamically connected to right atrium was in 2 patients. Pathoanatomical findings of complex congenital cardiovascular anomalies associated with L.S.V.C. in 16 cases were generally show unsystematic irregularity. In group I, A.S.D. were only in 3 cases, but in highest incidence and in group III, all two cases were supracardiac type of total anomalous drainage of pulmonary veins. Post-operatively, 3 patients among 14 patients of total correction, were died immediately, 1 patient of palliative shunt operation was died after 2 and half years, and Follow-up results of other remaining patients were excellent.

  • PDF

Experimental analysis of rocking shallow foundation on cohesive sand

  • Moosavian, S.M. Hadi;Ghalandarzadeh, Abbas;Hosseini, Abdollah
    • Earthquakes and Structures
    • /
    • 제22권6호
    • /
    • pp.597-608
    • /
    • 2022
  • One of the most important parameters affecting nonlinearsoil-structure interaction, especially rocking foundation, is the vertical factor of safety (F.Sv). In this research, the effect of F.Sv on the behavior of rocking foundations was experimentally investigated. A set of slow, cyclic, horizontal loading tests was conducted on elastic SDOF structures with different shallow foundations. Vertical bearing capacity tests also were conducted to determine the F.Sv more precisely. Furthermore, 10% silt was mixed with the dry sand at a 5% moisture content to reach the minimum apparent cohesion. The results of the vertical bearing capacity tests showed that the bearing capacity coefficients (Nc and Nγ) were influenced by the scaling effect. The results of horizontal cyclic loading tests showed that the trend of increase in capacity was substantially related to the source of nonlinearity and it varied by changing F.Sv. Stiffness degradation was found to occur in the final cycles of loading. The results indicated that the moment capacity and damping ratio of the system in models with lower F.Sv values depended on soil specifications such cohesiveness or non-cohesiveness and were not just a function of F.Sv.