• Title/Summary/Keyword: 2-D shape

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Tunnel Convergence and Crown Settlement Using 3D Laser Scanning (3 차원 레이저 스캐닝을 이용한 터널의 천단 및 내공 변위 관측)

  • Lee, Jae-One;Yun, Bu-Yeol
    • Journal of Korean Society for Geospatial Information Science
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    • v.15 no.2 s.40
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    • pp.67-75
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    • 2007
  • There are a number of risks in constructing tunnel-structures. Therefore, the precise and rapid observation about inside deformation of the tunnel is required to prevent these risks from occurring and to secure safety. But currently, the real situation is that the crown settlement, cavity deformation and ground surface settlement rely upon the universal mensuration which uses total station or various kinds of measuring instruments. Recently, according to improvement and progress of measuring technology, three-dimensional laser scanning is used as the method to provide data for maintaining structures. It solves the reliability problem of measuring method for the transformational volume of existing structures, provides data that enables to judge visually by three-dimensioning the shape change of structures and makes it possible to deliberate speedy countermeasure. And it can also be efficiently used in the structure maintenance and field measurement.

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Experimental Study to Improve the Performance of the Pretensioner for a Passenger Vehicle (자동차용 프리텐셔너의 성능향상을 위한 실험적 연구)

  • Jung, Sung-Pil;Park, Tae-Won;Song, Taeck-Rim
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.2
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    • pp.1-6
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    • 2010
  • This study presents the practical design modification to improve the retracting performance of the pyro-typed high power pretensioner. 3 components of the pretensioner are redesigned and the usefulness of the design modification is verified by the experiment. During the pretensioning process, the gas blast generated from the gunpowder is transferred to the rack-pinion gear through the manifold. The rack-pinion gear is connected with the spool where the webbing is rolled up. According to the rotation of the pinion, the spool is turned and the webbing is winded. To help the gas blast flow well, the shape of the inner cross section of the manifold is changed. The spur gear design program is developed and used to find the best combination of the rack-pinion gear pair to increase the power transmission efficiency. The pinion guide is installed on the spool to prevent the vibration of the pinion. As a result of the experiment, the amount of the web retraction length is increased when every single design modification is applied. Therefore, the retracting performance of the pretensioner is considered to be improved if the presented design modifications are applied.

Influence of the Flow Stress of the Rivet on the Numerical Prediction of the Self-Piercing Rivet (SPR) Joining (Self-Piercing Rivet 접합공정의 수치예측에 미치는 리벳 유동응력의 영향)

  • Kim, S.H.;Bae, G.;Song, J.H.;Park, K.Y.;Park, N.
    • Transactions of Materials Processing
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    • v.29 no.5
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    • pp.257-264
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    • 2020
  • This paper is concerned with the influence of the plastic property of the rivet on the numerical prediction of the Self-Piercing Rivet (SPR) Joining. In order to predict the plastic property of the rivet, a ring compression specimen was directly fabricated from the rivet used for the mechanical joining of dissimilar materials, and the FE analysis together with the ring compression test was iteratively carried out by changing the plastic property of the rivet. For reliable FE analysis, a friction coefficient was estimated based on a friction calibration curve, measuring the reductions in inner diameter and height of the ring specimen after the compression test. From each simulation result, the force-displacement curves were then compared from each other so as to obtain the rivet plastic property that shows good agreement with the experimental result. The SPR joining between GA590 1.0t and Al5052 2.0t was conducted, and the numerical prediction was performed with the use of the plastic property evaluated based on the inverse analysis and the one referred from Mori et al. [11]. Comparison of the experiment and the numerical predictions in terms of the interlock and bottom thickness revealed that the reliable evaluation of the plastic property of the rivet is necessary for the trustworthy numerical prediction of the SPR joining.

Quality Characteristic and Optimization of Iced Cookie with Addition of Jinuni bean(Rhynchosia volubilis) (쥐눈이콩(鼠目太) 첨가 냉동쿠키의 품질특성 및 최적화)

  • Ko, Young-Joo;Joo, Na-Mi
    • Korean journal of food and cookery science
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    • v.21 no.4 s.88
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    • pp.514-527
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    • 2005
  • The purposes of this study were firstly to optimize the recipe for iced cookies by cooking with five different ingredient levels of $Jinuni\;bean(X_1),\;butter(X_2)\;&\;sugar(X_3)$ and secondly to analyze the chemical and sensory test results by using RSM(Response Surface Methodology). As a result of this test, water activity decreased with increasing contents of butter or sugar, while hydrophilic browning decreased independently with increasing sugar content. There was a positive correlation(p<.001) between specific gravity and hardness, although the result was not uniform due to the interaction of each factor. There was a negative correlation(p<.001) between the spread ratio and gravity or hardness, and it tended to increase with increasing each content. Color value L and color value a had positive correlation (p<.001) and the value tended to decrease with increasing the quantity of Jinuni bean. Generally, the strength of the cookies showed a saddle point at the peak of the 3d graph. As a result of sensory evaluation, the color was sensitive to the contents of sugar and Jinuni bean, the texture was sensitive to the contents of butter and sugar, and the taste and overall quality were sensitive to all three factors. Color had a positive correlation(p<.05) with the taste, texture and overall quality. There were high positive correlations(p<.001) between the taste, texture and overall quality. The preference data showed an up-swollen, parabolic shape in the center of the 34 graph, which enabled the optimum value to be determined and the optimum mixture ratio which fulfilled all sensory items was Jinuni bean 93g, butter 188.5g and sugar 155g, indicating a substitution of flour by $44\%$.

Seven cases of Diphullobothrium latum infection (광절열두조충 인체 감염 7례)

  • 이순형;채종일
    • Parasites, Hosts and Diseases
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    • v.27 no.3
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    • pp.213-216
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    • 1989
  • Seven cases of Diphyllcbothrium latum infection were proved by collection of worms after prasiquantel treatment between October, 1986 and July, 1987. The patients were all males aged 20~44 years residing in Seoul or Ulungdo, Kyungpook Province. All of them had the history of eating several kinds of raw marine fishes, and they had never been to abroad. One of them exporienced abdominal pain and 6 experienced natural discharge of a chain of worm segments, but none revealed any sign of anemia, Total 12 worms (1~3/patient) were collected after praiiquantel treatment. The worms were 85~423 cm in length, and revealed the characteristic rosette-shape uterus in their gravid proglottides. The average egg size varied $61.0~65.3{\times}41.7~46.1{\;}{\mu\textrm{m}}$. The eggs were yellowish. brown, and ovoid to elliptical. Including the present 7 cases, the total number of human D. latum infections proven by worms in Korea becomes 28 cases.

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Study on the Optimum Design of High Pressure Common-rail DME Injector Nozzle with Consideration of Cavitation (공동현상을 고려한 커먼레일용 고압 DME 인젝터 노즐의 최적 설계 연구)

  • Jeong, Soo-Jin;Park, Jung-Kwon;Lee, Sang-In
    • Transactions of the Korean Society of Automotive Engineers
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    • v.21 no.1
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    • pp.99-106
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    • 2013
  • DME (Di-Methyl Ether) is synthetic product that is produced through dehydration of methanol or a direct synthesis from syngas. And it is able to save fossil fuel and reduce pollutants of emission such as PM and $CO_2$. In spite of its advantages it is difficult to design DME fuelled engine system because DME fuel may cause to severely generate cavitation and corrosion in fuel delivery system due to physical properties of DME. Therefore, in this study three-dimensional internal flow characteristics with consideration of cavitation were predicted in the DME injector using diesel and DME fuel. Moving grid technique was employed to describe needle motion and 1-D hydraulic simulation of injector was also simulated to obtain transient needle motion profiles. The results of simulation show that cavitations was generated at the inlet of nozzle near high velocity region both diesel and DME. And mass flow rate of DME is reduced by 4.73% compared to that of diesel at maximum valve lift because cavitation region of DME is much more larger. To increase flow rate of DME injector, internal flow simulation has been conducted to investigate the nozzle hole inner R-cut effect. The flow rates of diesel and DME increase as R-cut increases, and flow coefficient of DME fuel injector was increased by 6.3% on average compared with diesel fuelled injector. Finally, optimum shape of DME injector nozzle is suggested through the comparison of flow coefficient with variation of nozzle hole inner R-cut.

Optimization of Iced Cookie with the Addition of Dried Sweet Pumpkin Powder (건조 단호박을 첨가한 냉동쿠키의 제조조건 최적화)

  • Lee, Sun-Mee;Ko, Young-Joo;Jung, Hyeon-A;Paik, Jae-Eun;Joo, Na-Mi
    • Journal of the Korean Society of Food Culture
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    • v.20 no.5
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    • pp.516-524
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    • 2005
  • This study was conducted to develop a functional cookie with the addition of a sweet pumpkin powder on a cookie shape, that showed high preference level to all age group and that was very easily to store because of low moisture content, by substituting partially a sweet pumpkin powder for reducing content of wheat flour. This study has produced the sensory optimal composite recipe by making iced cookies, respectively, with each 5 level of Sweet pumpkin powder($X_{1}$), sugar($X_{2}$), butter($X_{3}$), by C.C.D(Central Composite Design) and conducting sensory evaluation and instrumental analysis by means of RSM(Response Surface Methodology). Sensory items showed very significant values in color, appearance, flavor, overall quality(p<0.05), texture(p<0.01), and instrumental analysis showed significant values in lightness, redness(p<0.01), yellowness, spread ratio, hardness(p<0.05). Also sensory optimal ratio of Sweet pumpkin cookie was calculated as sweet pumpkin powder 81.8g, sugar 116.6g, butter 210.7g, and it was revealed that the factors of influencing cookie aptitude were in order of Sweet pumpkin powder, butter, sugar.

Thermo-Sensitive Polyurethane Membrane with Controllable Water Vapor Permeation for Food Packaging

  • Zhou, Hu;Shit, Huanhuan;Fan, Haojun;Zhou, Jian;Yuan, Jixin
    • Macromolecular Research
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    • v.17 no.7
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    • pp.528-532
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    • 2009
  • The size and shape of free volume (FV) holes available in membrane materials control the rate of gas diffusion and its permeability. Based on this principle, a segmented, thermo-sensitive polyurethane (TSPU) membrane with functional gate, i.e., the ability to sense and respond to external thermo-stimuli, was synthesized. This smart membrane exhibited close-open characteristics to the size of the FV hole and water vapor permeation and thus can be used as smart food packaging materials. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), positron annihilation lifetimes (PAL) and water vapor permeability (WVP) were used to evaluate how the morphological structure of TSPU and the temperature influence the FV holes size. In DSC and DMA studies, TSPU with a crystalline transition reversible phase showed an obvious phase-separated structure and a phase transition temperature at $53^{\circ}C$ (defined as the switch temperature and used as a functional gate). Moreover, the switch temperature ($T_s$) and the thermal-sensitivity of TSPU remained available after two or three thermal cyclic processes. The PAL study indicated that the FV hole size of TSPU is closely related to the $T_s$. When the temperature varied cyclically from $T_s-10{\circ}C$ to $T_s+10^{\circ}C$, the average radius (R) of the FV holes of the TSPU membrane also shifted cyclically from 0.23 to 0.467 nm, exhibiting an "open-close" feature. As a result, the WVP of the TSPU membrane also shifted cyclically from 4.30 to $8.58\;kg/m^2{\cdot}d$, which produced an "increase-decrease" response to the thermo-stimuli. This phase transition accompanying significant changes in the FV hole size and WVP can be used to develop "smart materials" with functional gates and controllable water vapor permeation, which support the possible applications of TSPU for food packaging.

Text Detection and Recognition in Outdoor Korean Signboards for Mobile System Applications (모바일 시스템 응용을 위한 실외 한국어 간판 영상에서 텍스트 검출 및 인식)

  • Park, J.H.;Lee, G.S.;Kim, S.H.;Lee, M.H.;Toan, N.D.
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.46 no.2
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    • pp.44-51
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    • 2009
  • Text understand in natural images has become an active research field in the past few decades. In this paper, we present an automatic recognition system in Korean signboards with a complex background. The proposed algorithm includes detection, binarization and extraction of text for the recognition of shop names. First, we utilize an elaborate detection algorithm to detect possible text region based on edge histogram of vertical and horizontal direction. And detected text region is segmented by clustering method. Second, the text is divided into individual characters based on connected components whose center of mass lie below the center line, which are recognized by using a minimum distance classifier. A shape-based statistical feature is adopted, which is adequate for Korean character recognition. The system has been implemented in a mobile phone and is demonstrated to show acceptable performance.

A Study on the Vessel Structure of Fagaceae Species in Korea (II) -Micromorphology of Vessel Wall Sculpture- (한국산(韓國産) 참나무과(科) 수종(樹種) 도관구조(道管構造)에 관(關)한 연구(硏究)(II) -도관벽(導管壁)의 수식구조(修飾構造)-)

  • Lee, Sung Jae;Lee, Wan Yang
    • Journal of Forest and Environmental Science
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    • v.8 no.1
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    • pp.51-66
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    • 1992
  • This study was carried out to investigate the micromorphology of vessel wall sculpture such as shape of perforation plate, perforation rim, steepness of perforation plate, occurrence of vestured pit, warty layer and ray-vessel pitting on 13 species of Fagaceae in Korea. The results were summarized as follows ; 1. In the species examined, all sample species except Fagus crenata var. multinervis have simple perforation plate. But Fagus crenata var. multinervis has simple and scalariform perforation plate (it was called to combination perforation plate) in a tree stem. 2. The shapes of perforation rim could be classified into five types; Type A without tail, Type B with small tail on both sides, Type C with long tail on both sides, Type D with tail only one side and Type E with the very short interval between perforations. Among five types, Type Band C have higer frequency of distribution than the others. 3. The steepness of perforation plate measured was about 20 degree on pore zone and 43 degree on outside parts of pore zone. 4. Species with vestured pit were Q. aliena, Q, dentata, Q. variabilis, Fagus crenata var. multinervis, Castanopsis cuspidata var sieboldii, Q. acuta, Q. stenophylla, and Q. glauca. But the extent of vesturing was very slight and vestured pits were observed mainly in ray-vessel pit of some vessel elements. 5. Species with warty layer on the inner surface wall of all vessel elements were Q. acuta, Q. stenophylla, Q. glauca, Fagus crenata var. multinervis and species with warty layer of some vessel elements were Q. aliena, Q, dentata, Q. variabilis, Castanopsis cuspidata var. sieboldii. 6. Species with palisade ray-vessel pit were Q. acuta, Q. stenophylla, Q. glauca, Castanea crenata, Castanea bungeana, Q. aliena, Q. serrata, Q. mongolica, and species with scalariform ray-vessel pit was Fagus crenata var. multinervis and species with oval ray-vessel pit were Q, dentata, Castanopsis cuspidata var sieboldii.

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