• 제목/요약/키워드: Bar development

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Accelerated Seaward Growth of Tidal Sand Bar during Giant Dyke Construction off the Mangyung River Mouth, West Coast of Korea

  • Lee, Hee-Jun;Choi, Kang-Won;Eo, Dae-Su;Chu, Yong-Shik
    • Journal of the korean society of oceanography
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    • v.36 no.3
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    • pp.72-82
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    • 2001
  • The progress of giant dyke construction off the Mangyung and Donajin rivers, has yielded enormous impact on the estuarine environment, both hydrodynamically and sedimentologically. Especially the inter-dyke gap in the northern Saemankeum area, 4 km wide between Yamido and Piungdo, has acted as an artificial tidal inlet. Due to such a changed geometry, tidal regime has been reversed from being flood- to ebb-dominated with a directional change from NE-SW to E-W. As a result, a large tongue-like tidal sand bar (named Saemankeum Bar) has conspicuously grown seaward through the artificial tidal inlet. The Saemankeum Bar composed of well-sorted very fine sands (3.0-3.5${\phi}$) has grown at a rate of 1.63 km/yr for the past three yews (1996-1998). Such a rapid growth of the sand bar is attributed to enhanced sediment supply derived from the degradation of former tidal sand bars at the mouth of the Mangyung River. Eventually the reworking of the tidal sand bars also caused the pre-existing tidal channels to be wider, deeper and more straightened. All of these phenomena well examplify the critical effect of artificial modifications on the natural estuarine environments.

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Bar Development in Gravel-bed River (자갈하상하천의 bar지형 발달에 관한 연구 -골지천을 사례로-)

  • Yang, Hee-Kyung
    • Journal of the Korean Geographical Society
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    • v.32 no.4
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    • pp.435-444
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    • 1997
  • Bars in a river bed show the flow of the river, the shape of a river bar can be easily measured in any river. The purpose of this study is to research the morphological characteristics of river bars. The case study area is the lower Golgi River, six bars were examined. All six bars are gravel bars with a grain size in excess of 2 millimeters. Four of the bars are longitudinal bars, in which the direction of the bar follows the river current. After analyzing the gravel in the bars, it was determined that as the gravel flows down the river, gravel grain size decreases while grain roundness increases. The shape of bar varies locally according to flow regime, channel slope, and w/d ratio.

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Reed Solomon Encoding System of 4-state Bar Code for Automatic Processing in Mail Items (우편물 자동처리를 위한 4-state 바코드 Reed Solomon 인코딩 시스템)

  • 박문성;송재관;황재각;남윤석
    • Proceedings of the IEEK Conference
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    • 2000.11c
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    • pp.47-50
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    • 2000
  • Recently many efforts on the development of automatic processing system for delivery sequence sorting have been performed in ETRI , which requires the use of postal 4-state bar code system to encode delivery points. The 4-state bar code called postal 4-state bar code for high speed processing that has been specifically designed for information processing of logistics and automatic processing of the mail items. This paper describes a method of Reed-Solomon encoding for creating error correction codeword of 4-state bar code.

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Synthesis of four-bar linkage motion generation using optimization algorithms

  • Phukaokaew, Wisanu;Sleesongsom, Suwin;Panagant, Natee;Bureerat, Sujin
    • Advances in Computational Design
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    • v.4 no.3
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    • pp.197-210
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    • 2019
  • Motion generation of a four-bar linkage is a type of mechanism synthesis that has a wide range of applications such as a pick-and-place operation in manufacturing. In this research, the use of meta-heuristics for motion generation of a four-bar linkage is demonstrated. Three problems of motion generation were posed as a constrained optimization probably using the weighted sum technique to handle two types of tracking errors. A simple penalty function technique was used to deal with design constraints while three meta-heuristics including differential evolution (DE), self-adaptive differential evolution (JADE) and teaching learning based optimization (TLBO) were employed to solve the problems. Comparative results and the effect of the constraint handling technique are illustrated and discussed.

Development of Educational 6-axis Articulated Manipulator Using 4-bar Linkage (4-bar Linkage를 이용한 교육용 6축 수직 다관절 로봇 개발)

  • 김대영;김성현;박정미;정원지
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.524-527
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    • 2002
  • This paper is on the development of an educational 6-axis articulated manipulator using 4-bar linkage system. Especially, the 2$^{nd}$ and the 3$^{rd}$ axes need large torque to control the movement of an end-effect. However, small motors (RC-servo, DC-gear, stepping meters) are used for the 4-bar linkage. In addition the manipulator can be operated by a switch and also motion can be realized automatically, based on C-language coded users programs..

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Evaluation of Agronomic Characteristics, Nutritional Contents, and Insect Response of the Transgenic Potato Resistant to Glufosinate Ammonium (제초제 저항성 형질전환 감자의 농업적 특성, 영양 성분 및 해충 반응성 평가)

  • Ahn, Soon-Young;Cho, Kwang-Soo;Seo, Hyeo-Won;Yi, Jeong-Yoon;Bae, Shin-Cheol;Cho, Ji-Hong;Park, Young-Eun;Kim, Ju-Il;Kim, Hyun-Jun;Cho, Hyun-Mook
    • Horticultural Science & Technology
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    • v.29 no.3
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    • pp.247-254
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    • 2011
  • The agronomic characteristics, nutritional contents, and insect response of the potato clones transformed with a glufosinate ammonium resistance gene were evaluated. Among the 4 transgenic potato clones, the Bar 3 clone was selected as a promising one for commercialization. The Bar 3 clone showed similar tuber yield capacity but higher herbicide resistance as compared with the non-transgenic potato cv. Dejima. The herbicide resistance of the Bar 3 clone was more than 5 times higher when tested with the herbicide concentration recommended by the producer. The major agronomic characteristics of the Bar 3 clone were not different from those of the non-transgenic Dejima. The annual variation in yields and agronomic characteristics showed similar tendency for 2 years from the third to fourth generation after transformation. The tubers of the Bar 3 clone also showed low occurrence in common scab and physiological disorders such as cracking and secondary growth. But the reasons for such results are yet to be studied. Also, it was considered that the Bar 3 clone have a potential of reducing not only common scab occurrence but also soil erosion during potato cultivation in field. The nutritional contents (mineral compound, vitamin C and amino acid) and response to Spodoptera exigua of the transgenic potato clones were not significantly different.

Bond Strength and Development Length Model for Corroded Reinforcing Bars (부식된 철근의 부착강도 및 정착길이 산정모델)

  • Han, Sun-Jin;Lee, Deuckhang
    • Journal of the Earthquake Engineering Society of Korea
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    • v.28 no.5
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    • pp.267-274
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    • 2024
  • This study aims to propose a simplified equation for estimating the bond strength of corroded reinforcing bars. To this end, extensive parametric analyses were performed using the detailed analysis method presented in the authors' previous study, where a wide range of critical variables were considered, such as compressive strength of concrete, net cover thickness, and reinforcing bar diameter. The sensitivity in bond strength of the corroded reinforcing bar according to each variable was evaluated. On this basis, a simplified formula for the bond strength of the corroded reinforcing bar was derived through regression analysis. The proposed equation was rigorously tested and verified using the bond test results of corroded reinforcing bars collected from the literature. The results confirmed that the proposed equation could estimate the bond strengths of specimens with better accuracy than the existing models, providing a reliable tool for engineers and researchers. In addition, the proposed equation was used to analyze the development length required for corroded tensile reinforcement to exert its yield strength, and it showed that the cover thickness of concrete must be at least four times the diameter of the reinforcing bar to achieve the yielding strength of reinforcing bar even at a corrosion degree of more than 5.0%.

Development of Questionnaires for Differentiation of $q{\grave{i}}-x{\bar{u}}$, $xu{\grave{e}}-x{\bar{u}}$, $yang-x{\bar{u}}$, $y{\bar{i}}n-x{\bar{u}}$ analysis (기혈음양허손(氣血陰陽虛損) 변증(辨證) 분석을 위한 설문문항 개발)

  • Woo, Hong-Jung;Kim, Se-Hoon;Lee, Seung-Bo;Choi, Mi-Young;Kim, Young-Chul;Lee, Jang-Hoon
    • The Journal of Internal Korean Medicine
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    • v.29 no.4
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    • pp.856-870
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    • 2008
  • Objectives : Consumption is a chronic wasting disease and major portion of Oriental Medicine's therapy. However, there is no standard diagnostic method for consumption that is $q{\grave{i}}-x{\bar{u}}$, $xu{\grave{e}}-x{\bar{u}}$, $yang-x{\bar{u}}$, $y{\bar{i}}n-x{\bar{u}}$. Methods : A questionnaire which includes symptoms and signs for diagnosis of $q{\grave{i}}-x{\bar{u}}$, $xu{\grave{e}}-x{\bar{u}}$, $yang-x{\bar{u}}$, $y{\bar{i}}n-x{\bar{u}}$ was evaluated by Delphi technique. Each question was valuated by interviewing 27 oriental medicine doctors. Then. we choose questions given over 5 points and reorganized some items according to the recommendations by interviewed-doctors. We then accessed the value of re-organized questions composing of the questionnaires. Conclusion : We finally chose each 9 items of $q{\grave{i}}-x{\bar{u}}$, $xu{\grave{e}}-x{\bar{u}}$, $yang-x{\bar{u}}$, $y{\bar{i}}n-x{\bar{u}}$'s questionnaire. Further study is necessary for modification of questionnaire by statistics and certification by clinical trial.

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Study on the Effect on the Development Design of Headed Deformed Bars by change of ACI 318-19 (ACI 318-19 변경에 따른 확대머리철근 정착설계의 영향분석)

  • Lee, Byung Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2019.11a
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    • pp.110-111
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    • 2019
  • In ACI 318-19 published recently, the conditions and development length equation to use the headed deformed bars were changed considerably. Although the use of the larger-diameter(No.14 and 18) headed deformed bars isn't yet permitted, the use of the high strength(80,000psi) headed deformed bars is permitted and the effect of bar-diameter($d_b$) on the development length is increased considerably. Therefore, structures using larger-diameter headed deformed bars will be expected to be affected by this code change. We will study the effect of the code change on the development design and find out the design optimization method to minimize the effect of the changed conditions and development length equation.

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Experimental and Analytical Study on the Bus Duct System for the Prediction of Temperature Variations Due To the Fluctuation of Load

  • Thirumurugaveerakumar, S.;Sakthivel, M.;Valarmathi, S.
    • Journal of Electrical Engineering and Technology
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    • v.9 no.6
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    • pp.2036-2041
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    • 2014
  • In this paper, a thermal model is developed for the bus bar system to predict the temperature variation during the transient time period and to calculate both the steady-state and transient electrical current carrying capacity (ampacity) of bus bar. The bus bar system installed in the power house of Kumaraguru College of Technology, Coimbatore has been considered. Temperature variation predicted in the modelling is validated by observing the current and steady state temperatures in different feeders of the bus bar. Magnetic field of the extreme phases R and B induces more current in the middle phase Y. Hence, the steady state temperature in the phase Y is greater than other two phases. The transient capabilities of the bus bar are illustrated by calculating the variations in the bus bar temperature when it is subjected to a step change in current during the peak hours due to increase in hostel utilities and facilities (5.30 pm to 10.30 pm). The physical and geometrical properties of the bus bar and temperature variation in the bus bar are used to estimate the thermal time constants for common bus bar cross-sections. An analytical expression for the time constant of the bus bar is derived.