• Title/Summary/Keyword: Mass changes

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Study on an Acceleration Sensor using Magnetoelastic Effect of an Amorphous Wire (비정질 세선의 자기탄성 효과를 이용한 가속도 센서 개발에 관한 연구)

  • Cho, H.J.;Son, D.L.;Lim, S.J.;Yang, J.M.
    • Journal of Sensor Science and Technology
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    • v.2 no.1
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    • pp.11-17
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    • 1993
  • We have constructed an acceleration sensor which is based on the maximum magnetic induction changes of amorphous wire as a measurand. The frequency bandwith of the constructed sensor depends on the mass of a sensing element. For $Co_{72.5}Si_{12.5}B_{15}$ amorphous wire, the bandwith is DC-700 Hz for $1{\times}10^{-3}kg$ sensing element and DC-200 Hz for $5{\times}10^{-3}kg$. The linearity of the acceleration sensor was less than 1% within the acceleration of 5 g.

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Tendency of Traditional Character in Korean Modern House Architecture as an Art Work (한국 근.현대 주택작품에서 나타나는 전통성 해석의 시대적 경향)

  • Jun, Nam-Il
    • Korean Institute of Interior Design Journal
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    • v.19 no.1
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    • pp.169-179
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    • 2010
  • Since modernization period thru Japanese colonial era the modern architect began to play a important role for Korean housing architecture. So called 'House as an Art Work', detached houses by prominent architects, belong to a meaningful sector in Korean modern housing architecture. The harmony with tradition was always big issue for such works. This study aims to understand how paradigms for tradition were interpreted with the changes of the time. The analysis showed various tryout by architects, that concretize traditional characteristics in their work. For example, traditional lifestyle were clearly reflected in the floorplan during 30's and 40's. In the 70's building mass and formative roof design were emphasized to present traditional image. As well as it represented primitive esthetic and vernacular decoration. In addition, expressive tendency, that demonstrates korean sentiment through material and its texture, got a preference. Since latter half of 80's some traditional architectural elements were modernized and space characteristics were newly created from acculturation. Furthermore the philosophy of "Subdivision of building wings and Emptiness" follows this trend. This type made a courtyard and connected articulated building masses each other. "Sympathy with Nature" were most essential for a traditional houses in contrast with western architecture. Many architects today make various method to bring nature into interior space and to contemplate nature In the house. Such kinds of adaptation to tradition could be understood as a unique process to manifest identity of Korean modern houses.

Analysis of Output Characteristics of High-Power Shingled Photovoltaic Module due to Temperature Reduction (고출력 슁글드 태양광 모듈의 온도 저감에 따른 출력 특성 분석)

  • Bae, Jae Sung;Yoo, Jang Won;Jee, Hong Sub;Lee, Jae Hyeong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.6
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    • pp.439-444
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    • 2020
  • An increase in the temperature of photovoltaic (PV) modules causes reduced power output and shorter lifetime. Because of these characteristics, demands for the heat dissipation of PV modules are increasing. In this study, we attached a heat dissipation sheet to the back sheet of a shingled PV module and observed the temperature changes. The PV shingled module was tested under Standard Test Conditions (STCs; irradiance: 1,000 W/㎡, temperature: 25℃, air mass: 1.5) using a solar radiation tester, wherein the temperature of the PV module was measured by irradiating light for a certain duration. As a result, the temperature of the PV module with the heat dissipation sheet decreased by 3℃ compared to that without a heat dissipation sheet. This indicated that the power loss was caused by a temperature increase of the PV module. In addition, it was confirmed that the primary parameter contributing to the reduced PV module output power was the open circuit voltage (Voc).

Assessment of Two Wall Film Condensation Models of RELAP5/MOD3.2 in the Presence of Noncondensable Gas in a Vertical Tube

  • Park, Hyun-Sik;No, Hee-Cheon;Bang, Young-Seok
    • Nuclear Engineering and Technology
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    • v.31 no.5
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    • pp.465-475
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    • 1999
  • The objective of the present work is to assess the analysis capability of two wall film condensation models, the default and the alternative models, of RELAP5/MOD3.2 on condensation experiments in the presence of noncondensable gas in a vertical tube of PCCS of CP-1300. In the calculation of a base case the default model of RELAP5/MOD3.2 under-predicts the heat transfer coefficients, and Its alternative model over-predicts them throughout the condensing tube, Also, both models over-predict the void fractions. The nodalization study shows that the variation of the node number does not change both modeling results of RELAP5/MOD3.2 Sensitivity study for varying input parameters shows that the inlet steam-air mixture flow rate, the inlet air mass fraction, and the inlet saturated steam temperature give significant changes of their heat transfer coefficients Run statistics show that the grind time of the default model is always higher than that of the alternative model by about 23%.

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Grain Foreign Body Embedded in the Spleen and Immune-Mediated Hemolytic Anemia in a Maltese Dog

  • Song, Joong-Hyun;Jang, Hyo-Mi;Lee, Hee-Chun;Sur, Jung-Hyang;Kang, Byeong-Teck;Jung, Dong-In
    • Journal of Veterinary Clinics
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    • v.34 no.1
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    • pp.39-42
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    • 2017
  • An 8-month-old, intact male Maltese dog was referred to us because of anorexia, diarrhea, and jaundice. Hematologic examination revealed immune-mediated hemolytic anemia, and abdominal ultrasonography revealed heterogeneous changes in mesenteric fat and coarse echotexture in the splenic parenchyma. Septic peritonitis was diagnosed on the basis of a bacterial culture test of the peritoneal fluid. Exploratory laparotomy and subsequent omental biopsy and splenectomy were performed. On histopathological examination, the omental mass and splenic lesions were diagnosed as grain foreign body granulomas. This report describes a rare case in which a grain foreign body was embedded in the spleen of a dog.

A Study on the Blasting Dynamic Analysis Using Superposition Modeling Data (중첩모델링자료를 활용한 발파 동해석 기법에 관한 연구)

  • Park, Ji-Woo;Kang, Choo-Won;Go, Jin-Seok;Jang, Ho-Min
    • Tunnel and Underground Space
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    • v.18 no.4
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    • pp.280-288
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    • 2008
  • Since blast-induced vibration may cause serious problem to the rock mass as well as the nearby structures, the prediction of blast-induced vibration and the stability evaluation must be performed before blasting activities. Dynamic analysis using measurement vibration waveform which is measured by bore hole blasting or test blasting has been increased recently in order to analyze the effect of the blast-induced vibration. The waveform made by bore hole blasting has the similar vibration level and duration to those the waveform of sing hole has. However, there can be a little difference in attenuation characteristics with the blast induced vibration waveform in the field. Through the superposition modeling of single hole waveform, I obtained the vibration waveform on the blasting condition changes and conducted dynamic analysis using this waveform in this study.

Investigation on the In-Cylinder Flow of 5-Valve Gasoline Engine by Using Two Color PIV Method (이색 PIV 기술을 이용한 5밸브 가솔린엔진 연소실 내의 유동특성 분석)

  • Lee, Gi-Hyeong;U, Yeong-Wan;Park, Sang-Chan;Lee, Chang-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.2
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    • pp.238-244
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    • 2002
  • A 5-valve(intake 3-valve) engine has been developed to increase engine performance. These engines have a high power caused by the decrease of inertia mass of an intake valve and the increase of intake effective area. In this study, in-cylinder flow patterns were visualized with laser sheet method and velocity profiles at near intake valves were inspected by using a two-color PIV. In addition, steady flow tests were performed to quantify tumble ratio of flow-fields generated by a tumble control valve(TCV). Experimental results of steady flow test show that the cure of tumble ratio in intake 3-valve engine farmed as a S shape with valve lift changes. This tendency is different from the one in intake 2-valve engine. Using laser sheet method and two color PIV method, we can find that the intake flow through upper valve increases and the velocity gradient also slightly increases as valve lift increases. From this study, the in-cylinder flow characteristics around intake valves were made clearly.

Quality Changes of Traditional Kochujang Prepared with Different Meju and Red Pepper during Fermentation (고추장 메주와 고추 품종별 고추장의 발효특성 비교)

  • Kim, Moon-Sook;Kim, In-Won;Oh, Jin-A;Shin, Dong-Hwa
    • Korean Journal of Food Science and Technology
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    • v.30 no.4
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    • pp.924-933
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    • 1998
  • Kochujang, fermented hot pepper-soybean paste, was prepared by two common varieties of red pepper and natural fermented (NF) or pure cultured (PC) meju (soybean mass that is soaked, steamed, mashed and fermented by natural microflora or pure strain) and monitored their taste related component, enzyme activity and microflora during fermentation at $25^{\circ}C$ for 120 days for confirming possibility of kochujang fermentation control. The reducing sugars, amino type nitrogen (reference quality factor) and amino acid content in PC kochujang were 11.4%, 0.58% and 1,372.9 mg% respectively, 7.1%, 0.42% and 1,038.7 mg% in NF kochujang. It is concerned higher ${\alpha}-{\;}and{\;}{\beta}-{\;}amylase$ and, acid and neutral protease in PC kochujang during fermentation. The meju fermented by selected pure strain (A. oryzae CBU) can be applied to produced better quality of kochujang instead of natural meju.

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A Comparative Study of the Changes in Volatile Flavor Compounds from Dried Leeks (Allium tuberosum R.) following ${\gamma}$-Irradiation

  • Yang, Su-Hyeong;Shim, Sung-Lye;No, Ki-Mi;Gyawalli, Rajendra;Seo, Hye-Young;Song, Hyun-Pa;Kim, Kyong-Su
    • Food Science and Biotechnology
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    • v.15 no.3
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    • pp.341-346
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    • 2006
  • This study was performed to examine the effects of ${\gamma}$-irradiation on the volatile flavor compounds of dried leeks (Alliums tuberosum R.). Volatile compounds of dried leeks were extracted using simultaneous steam distillation and extraction (SDE), and analyzed by gas chromatography/mass spectrometry (GC/MS). Forty-one, 51, 45, and 42 compounds were tentatively identified in control, 1, 3, and 10 kGy irradiated samples, respectively. The constituents of flavor compounds in irradiated dried leeks were similar to non-irradiated samples. However, the intensities of the peaks were clearly different between them. Sulfur-containing compounds were detected as dominant compounds in all samples and their amounts decreased after ${\gamma}$-irradiation. ${\gamma}$-Irradiation reduced the total concentration of volatile compounds from leeks by 23.19, 15.09, and 30.23% at 1, 3, and 10 kGy doses, respectively.

Solubility Comparison by Yield Method of Residual of Photoresist for Printing Plate (인쇄 제판용 Photoresist의 잔막수율법에 의한 용해도 비교)

  • Yoon, Cheol-Hun;Hwang, Sung-Kwy;Oh, Se-Young;Chio, Sung-Yong;Lee, Ki-Chang
    • Journal of the Korean Applied Science and Technology
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    • v.15 no.1
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    • pp.25-33
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    • 1998
  • Photoresist is defined as substance that makes chemical changes in its solubility, colouring and hardening by light energy. In this study, photosensitive photoresists of the positive type for a printing plate were studied. PF, o-, m-, p-CF resins as a matrix resin were synthesized at an identical condition. Photoresists were prepared by mixing NDS derivatives with a matrix resin at various mixing ratios. Characteristics of photoresists were studied by yield method of residual using solubility and Optical microscope was also analyzed. Prepared photoresist using NDS derivatives shows excellent photosensitivity and solubility compared with commercial product. The mixing ratio of 1:4(by mass) of NDS derivative[III] and m-CF resin shows the highest dissoultion rate among others. In addition, photoresist was obtained at this condition resulted in the superior sensitivity and contrast.