• 제목/요약/키워드: H.A.Z

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S밴드 이중편파레이더의 부분 빔 차폐영역 내 반사도 보정을 통한 지상강우추정 개선 (Improved Rainfall Estimation Based on Corrected Radar Reflectivity in Partial Beam Blockage Area of S-band Dual-Polarization Radar)

  • 이정은;정성화;김해림;이선기
    • 대기
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    • 제27권4호
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    • pp.467-481
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    • 2017
  • A correction method of reflectivity in partial beam blockage (PBB) area is suggested, which is based on the combination of digital terrain information and self-consistency principle between polarimetric observation. First, the reflectivity was corrected by adding the radar energy loss estimated from beam blockage simulation using digital elevation model (DEM) and beam propagation geometry in standard atmosphere. The additional energy loss by unexpected obstacles and non-standard beam propagation was estimated by using the coefficient between accumulated reflectivity ($Z_H$) and differences of differential phase shift (${\Phi}_{DP}$) along radial direction. The proposed method was applied to operational S-band dual-polarization radar at Jindo and its performance was compared with those of simulation method and self-consistency method for six rainfall cases. When the accumulated reflectivity and increment of ${\Phi}_{DP}$ along radial direction are too small, the self-consistency method has failed to correct the reflectivity while the combined method has corrected the reflectivity bias reasonably. The correction based on beam simulation showed the underestimation. For evaluation of rainfall estimation, the FBs (FRMSEs) of simulation method and self-consistency principle were -0.32 (0.59) and -0.30 (0.57), respectively. The proposed method showed the lowest FB (-0.24) and FRMSE (0.50). The FB and FMSE were improved by about 18% and by 19% in comparison to those before correction (-0.42 and 0.70). We can conclude that the proposed method can improve the accuracy of rainfall estimation in PBB area.

Flow characteristics after water inrush from the working face in karst tunneling

  • Wu, J.;Li, S.C.;Xu, Z.H.;Pan, D.D.;He, S.J.
    • Geomechanics and Engineering
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    • 제14권5호
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    • pp.407-419
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    • 2018
  • In order to investigate flow characteristics after water inrush from the working face in process of karst tunnel construction, numerical calculation for two class case studies of water inrush is carried out by using the FLUENT software on the background of Qiyueshan tunnel. For each class water inrush from the tunnel face, five cases under different water-inrush velocity are simulated and researched. Three probing lines are selected respectively in the left tunnel, cross passage, right tunnel and in the height direction of the tunnel centerline. The variation characteristics of velocity and pressure on each probing line under the five water-inrush velocities are analyzed. As for the selected four groups probing lines in the tunnels, the change rules of velocity and pressure on each group probing lines under the same water-inrush velocity are discussed. Finally, the water flow characteristics after inrush from the tunnel face are summarized by comparing the case studies. The results indicate that: (1) The velocity and pressure change greatly at the intersection area of the cross passage and the tunnels. (2) The velocity nearby the tunnel side wall is the minimum, while it is the maximum in the middle position. (3) The pressure value of every cross section in the tunnels is basically fixed. (4) As water-inrush velocity increases, the flow velocity and pressure in the tunnels also increase. The former is approximately proportional to their respective water-inrush velocity, while the latter is not. The research results provide a theoretical basis for making scientific and rational escape routes.

조화된 측모상의 연경조직의 형태학적 연구 - 한국인 성인여자에 대하여 - (A MORPHOLOGICAL STUDY ON THE SOFT AND HARD TISSUE FACIAL PROFILE OF HARMONIOUS KOREAN YOUNG ADULT FEMALES)

  • 강구한;목하선지개
    • 대한치과교정학회지
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    • 제16권1호
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    • pp.7-34
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    • 1986
  • 본 연구목적은 여자성인교정을 위한 치료목표를 수립하기 위한 기준을 설정하는데 있다. 이용된 연구자료는 96명의 한국인 TV탈랜트와 영화배우 또는 패션모델중 교합과 안모를 평가하여 선정된 30명의 측모두부X선규격사진이었으며 선정된 표본의 평균연령은 20.16세였다. 연구방법은 측모경조직분석을 위해 Downs분석, Northwestern분석, Steiner분석, Wylie분석, Tweed분석, Dimensional linear분석법이 이용되었고 측모연조직분석을 위해 Holdaway연조직분석법이 적용되었다. 조사된 계측치들은 Apple II 48K system을 이용하여 각항목에 대한 평균치와 표준편차를 산출하였으며 백인, 한국인, 일본인의 기존계측치와 비교하였다. 그 연구결과는 다음과 같다. I. 경조직분석 (1) 본 연구와 백인과의 비교 본 연구에서는 백인에 비해 하악이 후퇴되었고 상${\cdot}$하악절치는 순측경사를 보였다. 또한 하악하연경사가 심했다. (2) 본 연구와 한국인정상성인여자(이 연구)의 계측치 비교 이의 연구계측치에 비해서 상악이 후퇴되어있고 상${\cdot}$하악절치는 설측경사를 보였다. 따라서 본 연구의 안모형태는 이의 한국인정상성인여자에 비해서 직선형안모를 보였다. (3) 본 연구와 일본정상인의 계측치 비교 일본정상인에 비해 하악이 돌출되었고 상${\cdot}$하절치는 설측경사를 보였다. 또한 안모의 상부고경과 하악크기는 일본정상인에 비해 크게 나타났다. II. 연조직분석 연조직분석의 11항목중 H-선에 대한 연조직 subnasal과 하순의 계측치가 Holdaway의 acceptable range를 벗어났다. 그 이유는 본연구에서 하악이 상대적으로 후퇴양상을 보였기 때문이라고 사료된다. 이외항목의 계측치들이 acceptable range내에 있다는 것은 연조직이 경조직의 이동에 따라 움직이고 있음을 의미한다. III. Downs분석, Northwestern분석, Steiner분석, Wylie분석, Tweed분석, Dimensional linear measurements분석을 위한 평균치, 표준편차, Polygon도표를 작성함으로써 한국성인여자교정의 진단과 치료목표를 정하는데 지침이 된다고 사료된다.

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넙치로부터의 Serine Protease의 분자생물학적 클로닝, 발현, 특성분석 (Molecular Cloning, Expression Analysis and Enzymatic Characterization of Elastase-like Serine Protease from the Olive Flounder (Paralichthys olivaceus))

  • 한진욱;서정수;안상중;이진영;박주현;김나영;김무상;황지연;정준기;이형호
    • 수산해양교육연구
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    • 제26권4호
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    • pp.808-822
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    • 2014
  • 넙치 (Paralichthys olivaceus)로부터 elastase-like serine protease (PoElSp)를 암호화하는 cDNA를 클로닝하여 그 서열을 분석한 결과, PoElSp 유전자는 269 아미노산을 암호화하는 978염기쌍으로 구성되었다. PoElSp 유전자의 조직 특이적 발현 양상을 RT-PCR법으로 조사한 결과, 간, 비장 및 소장에서 그 발현이 크게 나타났다. lipopolysaccharide (LPS)로 인위적 세균감염을 유도한 후, 1시간째에 콩팥에서, 3시간째에는 근육에서, PoElSp 유전자의 발현이 크게 증가하였다. 또한, 이 유전자의 발현은 비장에서 LPS 주입 후 1-24시간동안 점차로 증가하였다. pro-mature PoElSp (proPoElSp)에 해당하는 cDNA를 pET32a 벡터 시스템을 이용하여 대장균에서 발현시켰다. 이 재조합 proPoElSp 단백질의 활성은 gelatin zymography 방법과 합성형광 Z-Phe-Arg-AMC의 분해법을 이용하여 측정하였다. 단백질 분해효소 활성을 위한 최적 pH는 7.5였다. 실험결과들을 종합하면, PoElSp 단백질은 면역 반응에서 중추적 역할을 하리라 판단된다.

우울증 환자의 휴지기 슬밑 띠 피질의 기능적 뇌 연결성 (Resting-State Functional Connectivity of Subgenual Cingulate Cortex in Major Depression)

  • 고대욱;윤소영;최연선;신용욱
    • 대한불안의학회지
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    • 제10권2호
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    • pp.143-150
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    • 2014
  • Objective : The subgenual cingulate cortex, a part of default-mode network, has been known to playa key role in the pathophysiology of depression. The previous studies have reported abnormal functional connectivity between the subgenual cingulate cortex and other brain regions in the patients with depression. The goal of this shldy was to explore the resting-state functional connectivity of the subgenual cingulate cortex between the patients with depression and healthy subjects. Methods : Twenty patients with major depression and age- and sex-matched 20 healthy subjects underwent 5-minute resting state fMRI scans. The functional connectivity map in each subject was acquired using seed-based correlation analysis with the seed located in the subgenual cingulate cortex (Talairach coordinates; x=-10, y=5, z=-10). The functional connectivity maps were calculated using AFNI and compared between the patient and healthy subject group via two-sample T-test using 3dttest++ in AFNI package. Results : Functional connectivity was decreased between the subgenual cingulate cortex and both sides of fusiform gyrus in depressed subjects. Connectivity was also decreased between the subgenual cingulate cortex and the left cerebellum in the patient group. There was no correlation between the severity of depression and the degree of functional connectivity between the subgenual cingulate cortex and the regions showing decreased functional connectivity. Conclusion : Decreased resting-state functional connectivity between the subgenual cingulate cortex and both sides of fusiform gyrus, and decreased connectivity between the subgenual cingulate cortex and the left cerebellum found in the patients with major depression in comparison to the healthy subjects might be related to abnormal emotional and cognitive processing of depressed patients.

Effects of Dietary Fructooligosaccharide on Digestive Enzyme Activities, Intestinal Microflora and Morphology of Growing Pigs

  • Xu, Z.R.;Zou, X.T.;Hu, C.H.;Xia, M.S.;Zhan, X.A.;Wang, M.Q.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권12호
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    • pp.1784-1789
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    • 2002
  • One hundred and twenty-eight growing barrows (Jiaxing Black${\times}$Duroc${\times}$Landrace) at an average BW of 20.8 kg were allocated to four treatments for 42 days, each of which was replicated four times with eight pigs per replicate and used to investigate the effects of fructooligosaccharide (FOS) on digestive enzyme activities, intestinal microflora and morphology of growing pigs. The pigs received the same basal corn-soybean meal diet and FOS was added to the basal diet at 0, 2, 4, 6 g/kg diet at the expense of corn, respectively. As compared to control, supplementation with 4 and 6 g/kg FOS significantly improved average daily gain and feed efficiency. Addition of FOS enhanced the growth of Bifidobacterium and Lactobacillus, but inhibited Clostridium and Escherichia coli in the small intestinal and proximal colonic contents. Supplementation with 4 and 6 g/kg FOS significantly improved the activities of total protease, trypsin and amylase in the small intestinal contents. However, FOS had no significant effect on the activity of lipase in the small intestinal contents as well as the digestive enzymes in pancreas. Morphological measurement of jejunal mucosa did show response to consumption of FOS. Villus height and the villus height to crypt depth ratio at the jejunal mucosa were significantly higher with 4 and 6 g/kg FOS supplementation as compared to control.

Effect of Non-oxidized and Oxidized Soybean Oil Supplemented with Two Levels of Antioxidant on Broiler Performance

  • Anjum, M.I.;Alam, M.Z.;Mirza, I.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권5호
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    • pp.713-720
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    • 2002
  • A study was designed to determine the effects on broiler performance of two levels of antioxidant (ethoxyquin) in poultry rations containing two levels of oxidized and non-oxidized soybean oil. One hundred and eighty, day old broiler chicks were randomly divided into six experimental groups comprising thirty chicks on each treatment. Six experimental rations having 2% nonoxidized soybean oil, 2% and 3% oxidized soybean oil, all three supplemented with normal (125 g/t) or higher (175 g/t) level of ethoxyquin, were formulated for both starter (0-28 days) and finisher (29-42 days) phases. These rations were randomly fed to six experimental groups having 30 birds on each ration and three replicates on each treatment. Weight gain and feed conversion ratio (FCR) of chicks fed 2% non-oxidized and 2% oxidized soybean oil were statistically non-significant. Weight gain in groups fed 3% oxidized oil was significantly lower than non-oxidized group while FCR was significantly lower than both groups. Weight gain in the higher level ethoxyquin group was significantly better than lower level, while feed intake and FCR were statistically non-significant in both levels of ethoxyquin. Acid and Thiobarbituric Acid (TBA) values in the three groups differed significantly with the lower in non-oxidized group and highest in the 3% oxidized group. Higher level of ethoxyquin significantly lower acid and TBA values compared to lower level of ethoxyquin. Thus it can be concluded that oxidation of oil reduces its feeding value and that the addition of ethoxyquin is beneficial.

Local Environmental Effects on AGN Activities

  • 김재민;이석영
    • 천문학회보
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    • 제38권1호
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    • pp.43.2-43.2
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    • 2013
  • The local environmental effects on the triggering of active galactic nucleus(AGN) activity has been studied with many authors, but there still be controversy. We perform statistical analysis for nearby(0.01 < z < 0.05) volume limited(Mr < -19) samples with visual inspection based on Sloan Digital Sky Survey Data Release7. We inspect ~60,000 galaxy images visually to find peculiar objects which show not only ongoing merging features and tidal features, but also post merging features like ring or shell structures. We found that these peculiar features were shown at least 2 times more frequently among AGN host galaxies than non AGN galaxies, and this trend was still visible when galaxy properties such as color or stellar mass are fixed. Furthermore, L[OIII] and L(Ha) of peculiar galaxies are found to be more increased than those of normal galaxies. In order to ensure this results, we also checked it for a smaller subsample with ~2mag deeper monochromatic images provided from SDSS Stripe82 database, and found consistent results. At last, we perform the same work for pair(r_p<80kpc/h, delta_v<200km/s) systems. Because of some pair systems which do not interact gravitationally in actuality but fulfill the criteria for identification of pair system, the trends are found to be slightly weaker. We also found that line luminosities are increased consistently as projected distance between central and companion galaxy decreased, and as companion color gets bluer. Overall, the results of this study tell us that the local environment of galaxies affect the frequency as well as the strength of AGN activity. Local environmental effects, however, may not be the dominant triggering mechanism for AGN activity since the majority of peculiar galaxies are non AGN galaxies.

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Parametric modeling and shape optimization of four typical Schwedler spherical reticulated shells

  • Wu, J.;Lu, X.Y.;Li, S.C.;Xu, Z.H.;Li, L.P.;Zhang, D.L.;Xue, Y.G.
    • Structural Engineering and Mechanics
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    • 제56권5호
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    • pp.813-833
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    • 2015
  • Spherical reticulated shells are widely applied in structural engineering due to their good bearing capability and attractive appearance. Parametric modeling of spherical reticulated shells is the basis of internal analysis and optimization design. In the present study, generation methods of nodes and the corresponding connection methods of rod elements are proposed. Modeling programs are compiled by adopting the ANSYS Parametric Design Language (APDL). A shape optimization method based on the two-stage algorithm is presented, and the corresponding optimization program is compiled in FORTRAN environment. Shape optimization is carried out based on the objective function of the minimum total steel consumption and the restriction condition of strength, stiffness, slenderness ratio, stability. The shape optimization of four typical Schwedler spherical reticulated shells is calculated with the span of 30 m~80 m and rise to span ratio of 1/7~1/2. Compared with the shape optimization results, the variation rules of total steel consumption along with the span and rise to span ratio are discussed. The results show that: (1) The left and right rod-Schwedler spherical reticulated shell is the most optimized and should be preferentially adopted in structural engineering. (2) The left diagonal rod-Schwedler spherical reticulated shell is second only to left and right rod regarding the mechanical behavior and optimized results. It can be applied to medium and small-span structures. (3) Double slash rod-Schwedler spherical reticulated shell is advantageous in mechanical behavior but with the largest total weight. Thus, this type can be used in large-span structures as far as possible. (4) The mechanical performance of no latitudinal rod-Schwedler spherical reticulated shell is the worst and with the second largest weight. Thus, this spherical reticulated shell should not be adopted generally in engineering.

Dynamic risk assessment of water inrush in tunnelling and software development

  • Li, L.P.;Lei, T.;Li, S.C.;Xu, Z.H.;Xue, Y.G.;Shi, S.S.
    • Geomechanics and Engineering
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    • 제9권1호
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    • pp.57-81
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    • 2015
  • Water inrush and mud outburst always restricts the tunnel constructions in mountain area, which becomes a major geological barrier against the development of underground engineering. In view of the complex disaster-causing mechanism and difficult quantitative predictions of water inrush and mud outburst, several theoretical methods are adopted to realize dynamic assessment of water inrush in the progressive process of tunnel construction. Concerning both the geological condition and construction situation, eleven risk factors are quantitatively described and an assessment system is developed to evaluate the water inrush risk. In the static assessment, the weights of eight risk factors about the geological condition are determined using Analytic Hierarchy Process (AHP). Each factor is scored by experts and the synthesis scores are weighted. The risk level is ultimately determined based on the scoring outcome which is derived from the sum of products of weights and comprehensive scores. In the secondary assessment, the eight risk factors in static assessment and three factors about construction situation are quantitatively analyzed using fuzzy evaluation method. Subordinate levels and weight of factors are prepared and then used to calculate the comprehensive subordinate degree and risk level. In the dynamic assessment, the classical field of the eleven risk factors is normalized by using the extension evaluation method. From the input of the matter-element, weights of risk factors are determined and correlation analysis is carried out to determine the risk level. This system has been applied to the dynamic assessment of water inrush during construction of the Yuanliangshan tunnel of Yuhuai Railway. The assessment results are consistent with the actual excavation, which verifies the rationality and feasibility of the software. The developed system is believed capable to be back-up and applied for risk assessment of water inrush in the underground engineering construction.