• Title/Summary/Keyword: Sweeping

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A Study on Innovative Educational Practices in Cartoon Animation Education Program Through The Cartoon Promotion Act Legislation (만화진흥법 제정에 따른 대학만화교육의 개선 방안 제안)

  • Kim, Byoung-Soo;Lee, Won-Seok
    • Cartoon and Animation Studies
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    • s.23
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    • pp.81-94
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    • 2011
  • There is a growing movement of cartoon and animation circles to legislate the cartoon promotion act. It is anticipated that a wind of change will blow through the cartoon circle as private organizations are planned to established and a budget over 20 billion won is allocated. Although it is very encouraging for colleges who perform a substantial role in introducing new authors, a full internal discussion on the cartoon promotion act is still at a fledgling stage. Currently, the college restructuring craze is sweeping the country and cartoon animation education program can not be an exception. Especially, the irony of helping graduates who desire to be authors find jobs and expressing it as a statistical figure is too burdensome and worn out to regard it as an indiscretion of government. This study aims to examine the problems of cartoon animation college programs in South Korea by focusing on graduates' job-finding and career planning and to propose solutions through the legislation of cartoon promotion act.

Stink Bugs (Hemiptera) and Their Size, Collected near Jinju City, Gyeongnam Province (경남 진주 지역에서 채집된 노린재의 종류와 크기)

  • Lim, Eu-Gene;Park, Chung-Gyoo
    • Korean journal of applied entomology
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    • v.48 no.1
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    • pp.117-122
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    • 2009
  • True bugs were surveyed at the forest, bank of rice fields, and sweet persimmon orchard near Jinju city, Korea in 2006 and 2007. Number of species (individuals) collected at the forest, bank of rice fields and persimmon orchard are 24 (817), 21 (425) and 15 (193) species, respectively. A dominant species was Nysius plebeius at the forest, and Cletus punctiger at the bank of rice fields and persimmon orchard. In all the three sites N. plebeius, C. punctiger, and Pachygrontha antennata were more abundant than other species, consisting 77.8% of the total collections. N. plebeius was mainly collected on July at the bank of paddy field, and on August and after October at the forest. Most number of C. punctiger was collected from early July to early September at three sites. P. antennata was mainly collected after October at the forest. Body sizes of the stink bugs were measured.

A Study of Oscillation Characteristics of Supersonic Fluidic Oscillator With Shared Feedback Channel (공유피드백 유로를 갖는 초음속 유체진동기의 진동특성에 관한 연구)

  • Lee, SeungHeon;Park, SangHoon;Ko, HeeChang;Seo, SongHyun;Lee, Yeol
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.3
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    • pp.167-174
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    • 2020
  • A study of flow characteristics of supersonic fluidic oscillators with shared feedback channel inside was carried out. Unsteady CFD analysis were performed and the numerical results were validated by comparison with the experimental ones observed for the same operation conditions. It was found that the mass flow between individual oscillators through the shared feedback channel directly influenced on the oscillating flow mechanism inside the oscillator, and finally on the synchronization of the jet oscillations. It was also observed that the oscillator with shared feedback channel provided higher pressure loss as well as higher oscillation frequency as compared to the single oscillator of the same geometric shape.

Analysis of Hydrostatic Bulging of a Rectangular Diaphragm by Using the Energy Method (에너지법에 의한 직사각형 격막의 정수압벌징 해석)

  • 양동열;이항수
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.4
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    • pp.684-695
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    • 1992
  • The present study is concerned with the analysis of three-dimensional sheet metal forming process by the upper-bound method. For the analysis a systematic approach is necessary for the expression of geometric configuration of the deforming workpiece. In the present paper geometric configuration is constructed by three unit surfaces which are defined by sweeping the vertical section curves and boundary curve. The principal components of strain increment during the process is calculated directly from the change of geometric configuration for an arbitrary triangular element. The corresponding solution is found through optimization of the total energy consumption with respect to some parameters assumed in the velocity field and geometric profile. In order to verify the effectiveness of the present method, hydrostatic bulging of a rectangular disphragm is analyzed and the computation by the present method for the geometric shape renders the good result. From the comparison of the present results with the existing experimental results and elastic-plastic finite element solutions, good agreements have been obtained for the pressure curves, polar membrane strains and pressure distributions. The present method can thus be further applied to the analysis of other three-dimensional sheet metal forming processes.

On-line Estimation of Radial Immersion Ratio Using Cutting Force and Instantaneous Cutting Force Ratio in Face Milling (정면밀링 가공 중 절삭력과 순간 절삭력 성분비를 이용한 반경방향 절입비의 실시간 추정)

  • Kim, Myeong-Gon;Gwon, Won-Tae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.8 s.179
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    • pp.2123-2130
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    • 2000
  • Radial immersion ratio is an important factor to determine the threshold in face milling and should be estimated in process for automatic force regulation. In this paper, presented is a method of on-line estimation of the radial immersion ratio using cutting force. When a tooth finishes sweeping, sudden drop of cutting forces occurs. This force drop is equal to the cutting force that acts on a single tooth at the swept angle of cut and can be obtained from cutting force signal in feed and cross-feed direction. The ratio of cutting forces in feed and cross-feed directions acting on the single tooth at the swept angle of cut is a function of the swept angle of cut and the ratio of radial to tangential cutting force. In the research, it is found that the ratio of radial to tangential cutting force is not affected by cutting conditions and axial rake angle. Therefore, the ratio of radial to tangential cutting force determined by just one preliminary experiment can be used regardless of the cutting conditions. Using the measured cutting force and predetermined ratio, the radial immersion ratio is estimated. Various experiments show that the radial immersion ratio and instantaneous ratio of the radial to tangential direction cutting force can be estimated very well by the proposed method.

Efficiency and Comfort Properties of Silicon Solar Cell Applied Air Circulation Jacket according to the Incident Angle of Sunlight (실리콘 태양전지를 활용한 공기순환 의복의 태양광 입사각에 따른 효율성 및 쾌적성평가)

  • Lee, Ji-Yeon;Cho, A-Ra;Jung, Ye-Lee;Kim, Eun-Ae
    • Journal of the Korean Society of Clothing and Textiles
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    • v.33 no.11
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    • pp.1806-1816
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    • 2009
  • This study analyzes the efficiency of a solar cell attached to an air circulation jacket. A commercially available silicon solar panel was selected and attached at four spots where the body angle was $40-60^{\circ}$ and voltage ($V_{oc}$, V), current ($I_{sc}$, A), and output power (P, W) were measured to determine the efficiency. The solar panel was applied to the outer jacket that operates with two fans to increase the convection that lowers the body temperature. The heavy work of standing, walking, and sweeping of a street sweeper was simulated in the field test. The microclimate within the jacket (with or without a fan) was measured and the subjective thermal, humidity, and comfort sensations were surveyed. SPSS 12.0 statistical package was used for a t-test and Wilcoxon signed-rank test. The results show that the highest efficiency of the solar cell was at the incident angle of $60^{\circ}$ in terms of voltage, current and output power distribution. The microclimate temperature of the air circulation jacket decreased significantly with the high power of the fan and subjects felt cooler than the jacket with a fan at the incident angle of $60^{\circ}$. Air circulation jackets operated by a silicon solar panel showed a significant cooling effect on the wearers.

Computational Flow Analysis on Wind Profile Change Projected to a Wind Turbine Behind Saemangeum Seawall (새만금 방조제에 의한 풍력터빈 입사풍 변화의 전산유동해석)

  • Woo, Sang-Woo;Kim, Hyun-Goo
    • New & Renewable Energy
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    • v.9 no.1
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    • pp.6-11
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    • 2013
  • Jeollabuk-do has announced a future plan for the Saemangeum Wind Farm which includes the installation of fourteen wind turbines in a single line, located 500m back from the Saemangeum Seawall. It is anticipated as a positive effect that, for sea breeze blowing toward land, the average wind speed could be accelerated and the wind speed distribution could be uniformized by dint of the seawall, an upstream structure of the turbines. At the same time it is also anticipated as a negative effect that the strength of wind turbulence could be increased due to the flow separation generated at the back end of the seawall. According to the results of the computational fluid dynamics analysis of this paper, it has been observed that, at the 50m zone on the road surface located at the uppermost part of the Saemangeum Seawall, the average wind speed has been accelerated by approximately 6~7% and that wind shear has been decreased by 70%, but this positive effect disappears in the zone situated beyond the 100m from the back end of the seawall. It has also been observed that flow separation exists to a limited extent only below the bottom of the blade-sweeping circle and, furthermore, does not extend very far downstream of the wind. As a conclusion, it can be said that the seawall neither positively nor negatively affects the proposed Saemangeum Seawall Wind Farm layout.

BCI Probe Emulator Using a Microstrip Coupler (마이크로스트립 커플러 구조를 이용한 BCI 프로브 Emulator)

  • Jung, Wonjoo;Kim, SoYoung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.25 no.11
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    • pp.1164-1171
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    • 2014
  • Bulk Current Injection(BCI) test is a method of injecting current into Integrated Circuit(IC) using a current injection probe to qualify the standards of Electromagnetic Compatibility(EMC). This paper, we propose a microstrip coupler structure that can replace the BCI current injection probe that is used to inject a RF noise in standard IEC 62132-part 3 documented by International Electrotechnical Commission. Conventional high cost BCI probe has mostly been used in testing automotive ICs that use high supply voltage. We propose a compact microstrip coupler which is suitable for immunity testing of low power ICs. We tested its validity to replace the BCI injection probe from 100 MHz to 1,000 MHz. We compared the power[dBm] that is needed to generate the same level of noise between current injection probe and microstrip coupler by sweeping the frequency. Results show that microstrip coupler can inject the same level of noise into ICs for immunity test with less power.

A simulation-based design study of superconducting zonal shim coil for a 9.4 T whole-body MRI magnet

  • Kim, Geonyoung;Choi, Kibum;Park, Jeonghwan;Bong, Uijong;Bang, Jeseok;Hahn, Seungyong
    • Progress in Superconductivity and Cryogenics
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    • v.22 no.1
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    • pp.12-16
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    • 2020
  • As high homogeneity in magnetic field is required to increase the resolution of MRI magnets, various shimming methods have been researched. Using one of them, the design of the superconducting active zonal shim coil for MRI magnets is discussed in this paper. The magnetic field of the MRI magnet is expressed as the sum of spherical harmonic terms, and the optimized current density of shim coils capable of removing higher-order terms is calculated by the Tikhonov regularization method. To investigate all potential designs derived from calculated current density, 4 sweeping parameters are selected: (1) axial length of shim coil zone; (2) radius of shim coils; (3) exact axial position of shim coils; and (4) operating current. After adequate designs are determined with constraints of critical current margin and homogeneity criterion, the total wire length required for each is calculated and the design with a minimum of them is chosen. Using the superconducting wire length of 9.77 km, the field homogeneity over 50 cm DSV is improved from 24 ppm to 1.87 ppm in the case study for 9.4 T whole-body MRI shimming. Finally, the results are compared with the finite element method (FEM) simulation results to validate the feasibility and accuracy of the design.

Insect Diversity on the Paddy Field Wetland, Gonggeom-ji, Sangju, first designed by Ministry of Environment, Korea (국내 최초 환경부 지정 논 습지 지역인 공검지의 곤충 다양성)

  • Kim, Myeong-Hwan;Hwang, Jeong-Ho;Choi, Eun-Young;Park, Jinyoung;Park, Jong-Kyun
    • Journal of Wetlands Research
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    • v.19 no.1
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    • pp.155-163
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    • 2017
  • This study was conducted to know the wetland insect diversity at Gonggeom-ji in Sangju city which is the first designated paddy field wetland protection by the Ministry of Environment of Korea in 2011. Data was collected at four times from March to November in 2014 using by Searching, Sweeping and Pitfall trap methods. In this study a total of 227 species of 205 genera belonging to 78 families from 8 orders were collected and individuals were 1,327. Among them, the order of Coleoptera was the most species-rich (42.73%), Hemiptera was the second order (22.47%). In the total diversity index (H') was 6.339 that means highly positive. Dominant Index (DI) was 0.143, Evenness index (EI) was 0.810. Over all survey periods, interspecies competitiveness was high, and community stability was also high. Therefore Gonggeom-ji wetland revealed stable and positive environmental situation.