• Title/Summary/Keyword: four point method

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A Study on the Characteristics of the Residual Stress Distribution of Steel Structural Members (용접(鎔接) 강구조(鋼構造) 부재(部材)의 잔류응력(殘留應力) 특성(特性)에 관한 연구(研究))

  • Chang, Dong Il;Kim, Doo Hwan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.7 no.1
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    • pp.93-101
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    • 1987
  • Residual stresses have remained around welding areas of a steel structure member after welding operation. The major causes to occur these residual stresses are the local heat due to a welding, the heat stresses due to a irregular and rapid cooling condition, the material and rigidity of a steel structure. Ultimatly, these residual stresses have been known to decrease a brittle fracture strength, a fatigue strength, a buckling strength, dynamic properties, and the corrosion resistance of the material. This paper deals with the residual stresses on a steel structure member through experimental studies. SWS 58 plates were welded by the method of X-groove type. These plates were layed on the heat treatment at four different temperatures; $350^{\circ}C$, $500^{\circ}C$, $650^{\circ}C$ and $800^{\circ}C$. The resulting residual Stresses were measured by hole drilling method, and the followings were obtained. The residual stresses on the vicinity of a welding point were relieved most effectively at the temperature of $650^{\circ}C$, and these stresses relieved completly when the ratio of a hole diamerter to a hole depth became unity. Hardness test shows that the higher value of hardness at the heat affected zone dropped to belower as the temperature went up from $350^{\circ}C$ to $800^{\circ}C$. The Welding input heats have not influenced the magnitude of residual stresses at the input heat range between above and below one forth than standard.

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Plantar foot pressure analysis during golf swing motion using plantar foot pressure measurement system (족저압력분포 측정장비를 이용한 골프 스윙시 족저압 분석)

  • Lee, Dong-Ki;Lee, Joong-Sook;Lee, Bom-Jin;Lee, Hun-Sik;Kim, Young-Jae;Park, Seung-Bum;Joo, Jong-Peel
    • Korean Journal of Applied Biomechanics
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    • v.15 no.1
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    • pp.75-89
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    • 2005
  • D. K. LEE, J. S. LEE, B. J. LEE, H. S. LEE, Y. J. KIM, S. B. PARK, J. P. JOO. Plantar foot pressure analysis during golf swing motion using plantar foot pressure measurement system. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 75-89, 2005. In this study, weight carrying pattern analysis and comparison method of four foot region were suggested. We used three types of club(driver, iron7, pitching wedge). This analysis method can compare between top class golfer and beginner. And the comparison data can be used to correct the swing pose of trainee. If motion analysis system, which can measure the swing speed and instantaneous acceleration at the point of hitting a ball, is combined with this plantar foot force analysis method, new design development of golf shoes to increase comfort and ball flight distance will be available. 1. Address acting, forces concentrated in rare foot regions and lateral foot of right foot. Back swing top acting, relatively high force occurred in medial forefoot region of left foot and forefoot region of right foot. Impact acting, high force value observed in the lateral rarefoot region of left foot and medial forefoot region of right foot. Finish acting, force concentration observed on the lateral region and rarefoot region of left foot. 2. Forces were increased in address of right foot with clubs length increased. All clubs, back swing top acting, high force value observed in the lateral forefoot region of right foot. All clubs, in impact, high force value observed in the lateral rarefoot region of left foot and medial forefoot region of right foot. Finish acting, force concentration observed on the rarefoot region in driver and lateral foot region in iron on left foot. 3. Right foot forces distribution were increased in address, back swing top and left foot force distribution were increased in impact, finnish

The Effects of Raw and Physical Processed Common Vetch Seed (Vicia sativa) on Laying Performance, Egg Quality, Metabolic Parameters and Liver Histopatology of Laying Hens

  • Kaya, Hatice;Celebi, S.;Macit, M.;Geyikoglu, F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.10
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    • pp.1425-1434
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    • 2011
  • This experiment was designed to evaluate the effects of the processing method of common vetch seed (CVS) (Vicia sativa) on laying performance, egg quality, metabolic parameters and liver histopatology during the peak production period in hens. Lohman layers, 46 wk of age in 6 replicate cages each containing 4 hens, were allocated randomly to one of four dietary treatments. Diets were control (C) diet containing no common vetch and experimental diets containing 25% raw common vetch (RCV), 25% soaked in water for 72 h with exchange of water every 24 h (SCV) and 25% soaked&boiled at $100^{\circ}C$ for 30 minute common vetch (SBCV). Inclusion of RCV into the diet deteriorated all laying performance variables. SCV did not alleviate the adverse effect of raw common vetch on feed intake, egg weight, feed conversion, final weight and weight change. SCV partially alleviated egg production (p<0.001). SBCV diminished the adverse effect on feed intake, egg weight, feed conversion, final weight and weight change compared to raw vicia sativa (p<0.001). No significant difference was detected between SBCV and the control group in terms of egg production, feed conversion, final weight and weight change. Regardless of the processing method, all the common vetch groups had lower shell strength compared to the control group. Haugh units did differ between all groups (p<0.001). Inclusion of RCV and SCV into the basal diet decreased triglyceride, cholesterol, total protein and serum glucose concentrations (p<0.001). Hovewer, inclusion of SBCV into the basal diet increased these parameters. Liver samples were stained with Hematoxylin and eosin (HE) and evaluated by light microscopy. A biopsy of native liver tissue was used as a control. No histopathologic finding was present in the control group. Raw V. sativa compared with the control caused lipid accumulations in hepatocytes, severe congestion of hepatic blood vessels, inflammation, increased numbers of Kupffer cells and sinusoidal dilatations. Whereas, the livers from groups given treated V. sativa showed only different degrees of sinusoidal dilatations. Findings from the present study point out the risk of increased hepatic damage due to use of raw Vicia sativa. Increasing treatment of V. sativa lead to a decrease of liver damages. Inclusion of raw and soaked vetch seeds in rations affected adversely all parameters examined in laying hens. But alleviation was observed when soaked and boiled vetch seeds (SBCV) were fed. The results of these experiments indicated that soaked&boiled Vicia sativa seeds may safely be used at a 25% level in rations of laying hens.

Detection of HER2 Status in Breast Cancer: Comparison of Current Methods with MLPA and Real-time RT-PCR

  • Pazhoomand, Reza;Keyhan, Elahe;Banan, Mehdi;Najmabad, Hossein;Karimlou, Masoud;Khodadad, Faranak;Iraniparast, Alireza;Feiz, Farnaz;Majidzadeh, Keivan;Bahman, Ideh;Moghadam, Fatemeh Aghakhani;Sobhani, Atoosa Madadkar;Abedin, Seyedeh Sedigheh;Muhammadnejad, Ahad;Behjat, Farkhondeh
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.12
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    • pp.7621-7628
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    • 2013
  • Human epidermal growth factor receptor (HER) status is an important prognostic factor in breast cancer. There is no globally accepted method for determining its status, and which method is most precise is still a matter of debate. We here analyzed HER2 mRNA expression by quantitative reverse transcription-PCR (qRT-PCR) and HER2 DNA amplification using multiplex ligation-dependent probe amplification (MLPA). In parallel, we performed a routine evaluation of HER2 protein by immunohistochemistry (IHC). To assess the accuracy of the RT-PCR and MLPA techniques, a combination of IHC and fluorescence in situ hybridization (FISH) was used, substituting FISH when the results of IHC were ambiguous (2+) and for those IHC results that disagreed with MLPA and qRT-PCR, this approach being termed IHC-FISH. The IHC results for four samples were not compatible with the MLPA and qRT-PCR results; the MLPA and qRT-PCR results for these samples were confirmed by FISH. The correlations between IHC-FISH and qRT-PCR or MLPA were 0.945 and 0.973, respectively. The ASCO/CAP guideline IHC/FISH correlation with MLPA was (0.827) and with RT-PCR was (0.854). The correlations between the IHC results (0, 1+ as negative, and 3+ as positive) and qRT-PCR and MLPA techniques were 0.743 and 0.831, respectively. Given the shortcomings of IHC analysis and greater correlations between MLPA, qRT-PCR, and FISH methods than IHC analysis alone with each of these three methods, we propose that MLPA and real-time PCR are good alternatives to IHC. However a suitable cut-off point for qRTPCR is a prerequisite for determining the exact status of HER2.

Evaluation of the Structural Performance of Tetragonal Lattice Girders (사각 격자지보의 구조 성능 평가)

  • Kim, Seung-Jun;Han, Keum-Ho;Won, Deok-Hee;Baek, Jung-Sik;Kang, Young-Jong
    • Journal of Korean Society of Steel Construction
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    • v.24 no.3
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    • pp.267-278
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    • 2012
  • In general, the H-shaped steel ribs or triangular lattice girders have been mostly used in constructing tunnels through the NATM construction method. The H-shaped steel rib has higher flexural and axial strength than the triangular lattice girder, but many unexpected gaps can occur in the concrete lining system after shotcreting if the H-shaped steel rib is used as the support system. To achieve better shotcreting quality, the triangular lattice girder was developed. However, in general, the triangle lattice girder has low flexural and axial strength. Likewise, the triangular lattice girder, which has circular sectional members, has so many fractures from welded points at the joints between the members. Finally, the new type of tetragonal lattice girder was developed to overcome those problems. In this study, the structural performance of the tetragonal lattice girders was evaluated through analytical and experimental studies. In the analytical studies, the four-point bending analysis, the traditional evaluation method to determine the flexural strength of the lattice girder, was performed. Moreover, the linear-elastic analysis and stability analysis of the arch structure made by the lattice girders were performed to measure structural performance. Experiments were likewise performed to compare the structural performances of the tetragonal girder with traditional triangular lattice girders.

Property of Focal Spot of Electron Beam Depending on the Anode Angle of X-ray Tube Using a Finite Element Method (유한요소법을 이용한 X-선관 양극각도에 의존하는 전자빔 초점 특성 연구)

  • Park, Tae-Young;Noh, Young-Il;Lee, Sang-Suk;Park, Rae-Jun;Kim, Ki-Seon
    • Journal of the Korean Magnetics Society
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    • v.25 no.2
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    • pp.52-57
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    • 2015
  • The focal spot of electron beam depending on the anode angle in the structure and major parts of the X-ray tube was investigated by the OPERA-3D/SCALAR simulation program. The simulation worked on four spaces with with two spaces, including anode and cathode of X-ray tube, by applying the finite element method analysis. The analytical model and dimension for the emission orbit of thermal electrons made from one filament of the focused X-ray cathode is affected to the penumbra of detector for the X-ray depending on any real focal spot size. The model shape of focusing cap and focusing tube with an anode target angle and a cathode filament is analyzed by the current density distribution of thermal electrons. The focusing width of thermal electrons for the X-ray tube depended on the anode angle (${\theta}$). The focusing value of electron beams at a region of anode angle having $10^{\circ}{\sim}17^{\circ}$ maintained to below value of $70{\mu}m$. The minimum focal size of the electron beam was $40{\mu}m$ at an anode angle of $15^{\circ}$. The focused X-ray tube of many variables depended on the thermionic emission of hot electrons from the target trajectory. The focusing tube will contribute to the real design of X-ray for the development of future diagnosis medical device.

Rheological Properties of Bitumen for Reducing Negative Skin Friction (말뚝 부마찰력 저감용 역청재료의 유변학적 특성)

  • 박태순;윤수진
    • Journal of the Korean Geotechnical Society
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    • v.19 no.4
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    • pp.191-200
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    • 2003
  • This paper presents the rheological properties of bitumen for reducing negative skin friction. The bitumen has been widely used due to both the cost and construction effectiveness. Also, it is well known that the use of bitumen for reducing negative skin friction renders the best results among other available methods. Three different modified bitumens were used for the testing programs. The physical tests include the penetration, the softening point and penetration index. The rheological tests include phase angle, complex modulus, creep tests and flow tests. The tests were conducted at four different temperatures(15, 30, 45 and 6$0^{\circ}C$) in order to simulate the field condition. The test results were analyzed using the phase angle, G$^*$/sin $\delta$, creep compliance and shear viscosity. The result of tests showed that the phase angle increased and G$^*$/sin $\delta$ decreased with the increase of temperature. The creep compliance increased as the loading time increased. The difference of the creep compliance is detected as the time and temperature are varied, however, the difference of the shear viscosity is not significant among the samples tested in this study. The rheological properties of the bitumen also showed that the physical testing method and the temperature dependant testing method are somewhat limited to showing and expressing the full rheological properties of the modified bitumen. The introduction of the time and the temperature dependent testing method is necessary to find out the full rheological properties of the modified bitumen.

Application of a Convolution Method for the Fast Prediction of Wind-Induced Surface Current in the Yellow Sea and the East China Sea (표층해류 신속예측을 위한 회선적분법의 적용)

  • 강관수;정경태
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.7 no.3
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    • pp.265-276
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    • 1995
  • In this Paper, the Performance of the convolution method has been investigated as an effort to develop a simple system of predicting wind-driven surface current on a real time basis. In this approach wind stress is assumed to be spatially uniform and the effect of atmospheric pressure is neglected. The discrete convolution weights are determined in advance at each point using a linear three-dimensional Galerkin model with linear shape functions(Galerkin-FEM model). Four directions of wind stress(e.g. NE, SW, NW, SE) with unit magnitude are imposed in the model calculation for the construction of data base for convolution weights. Given the time history of wind stress, it is then possible to predict with-driven currents promptly using the convolution product of finite length. An unsteady wind stress of arbitrary form can be approximated by a series of wind pulses with magnitude of 6 hour averaged value. A total of 12 pulses are involved in the convolution product To examine the accuracy of the convolution method a series of numerical experiments has been carried out in the idealized basin representing the scale of the Yellow Sea and the East China Sea. The wind stress imposed varies sinusoidally in time. It was found that the predicted surface currents and elevation fields were in good agreement with the results computed by the direct integration of the Galerkin model. A model with grid 1/8$^{\circ}$ in latitude, l/6$^{\circ}$ in longitude was established which covers the entire region of the Yellow Sea and the East China Sea. The numerical prediction in terms of the convolution product has been carried out with particular attention on the formation of upwind flow in the middle of the Yellow Sea by northerly wind.

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The GEO-Localization of a Mobile Mapping System (모바일 매핑 시스템의 GEO 로컬라이제이션)

  • Chon, Jae-Choon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.5
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    • pp.555-563
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    • 2009
  • When a mobile mapping system or a robot is equipped with only a GPS (Global Positioning System) and multiple stereo camera system, a transformation from a local camera coordinate system to GPS coordinate system is required to link camera poses and 3D data by V-SLAM (Vision based Simultaneous Localization And Mapping) to GIS data or remove the accumulation error of those camera poses. In order to satisfy the requirements, this paper proposed a novel method that calculates a camera rotation in the GPS coordinate system using the three pairs of camera positions by GPS and V-SLAM, respectively. The propose method is composed of four simple steps; 1) calculate a quaternion for two plane's normal vectors based on each three camera positions to be parallel, 2) transfer the three camera positions by V-SLAM with the calculated quaternion 3) calculate an additional quaternion for mapping the second or third point among the transferred positions to a camera position by GPS, and 4) determine a final quaternion by multiplying the two quaternions. The final quaternion can directly transfer from a local camera coordinate system to the GPS coordinate system. Additionally, an update of the 3D data of captured objects based on view angles from the object to cameras is proposed. This paper demonstrated the proposed method through a simulation and an experiment.

Refusal of care by chronically and terminally ill patients : An ethical problem faced by nurses (간호사의 간호 제공 의무와 말기 환자의 간호 거부에 관련된 윤리 문제에 관한 연구)

  • 엄영란;홍여신
    • Journal of Korean Academy of Nursing
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    • v.24 no.2
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    • pp.190-205
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    • 1994
  • Respect for human life and respect for human dignity are two basic values to which organized nursing has urged its members to adhere in their service to mankind. Thus it is the nurses’ duty to provide health care in support of sustenance of life and to pay respect for the patient’s right to dignity. In practice, however, nurses may experience dilemmas between these duties much due to the de velopment of modern advanced techniques. These dilemmas have become more complex and difficult to resolve. Nurses are often faced with situations in which the terminally ill refuse professional care, posing serious conflicts between respect for human life and respect for human rights to self-determination. In such cases, resolution of the problem is not a simple matter, thus requires intensive study into the ethical questions related to the situation. The purpose of this study was to identify ethical problems that nurses experience in caring for terminally ill patients and explore the ways to the resolution of problems within the context of the situations. The methodology used for the study was a case study method which ‘New Casuistry’ proposed by Jonsen & Toulmin(1988) and the ‘Specified Principlism’ proposed by Degrazia(1992) as an alternative to old deductive and intuitive method. Cases were developed through semistructured indepth interviews according to the casutistry method. A total of seven nurses were interviewd who were caring for therminally ill patients. Four cases out of a total 14 cases were related to the topic. Through the case analysis it became evident that nurses appreciated other values more often than respect for the patient’s right to self-determination. These other values were convenience and efficiency in nursing practice in case 1, preservation of life above all other values in case 2, provision of nursing care to fulfill the nurse’s professional obligation at most in case 3, and respect for the family’s demand against the patient’s wish in case 4. This study showed that the most important ethical problems were conflict between respect for the patient’s right to self-determination and sustenance of life for the fulfillment of professional obligation. For this problem, benefit /burden analysis from the perspective of the patient and family for the promotion of patient’s wellbeing may be a way to resolve the conflict. Further, through these analysis it was shown that physicians’ and families’ opinions dominated in the decision - making and the opinions of nurses’ and patients’ tended not to be reflected. Thus the patient's right to his or her care was not readily respected. To solve this problem. nurses should make efforts to communicate reciprocally with their patients, family members and physicians in an effort to respect for their patient’s rights to life and diginity from the point of view and values of the patient. It is also important that nurses provide good basic nursing care up to the time of death regardless of decisions about providing or not aggressive treat-ment for chronically and terminally ill patients.

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