• Title/Summary/Keyword: 중력중심

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Practices of Teaching Methods based on the Type of Knowledge in Geography Education (지식의 유형에 근거한 지리과 수업 방법의 실제)

  • 심광택;김일기
    • Journal of the Korean Geographical Society
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    • v.32 no.2
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    • pp.197-215
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    • 1997
  • The purpose of this study is to show practices of teaching method based on the type of knowledge in geography education. The results of examining the type of knowledge according to the five themes in guidelines for geographic education in america are as follows: the empirical-analytic knowledge-centered contents are suited for designing concepts inquiry-centered teaching. The historical-hermeneutic knowledge-centered contents are suited for designing problem solving-centered teaching. The critical knowledge-centered contents are suited for designing decision-making-centered teaching. In this shsdy, 1 emphasized teaching method based on the type of knowledge in Ceographv Education according to the responses of students and academic achievement. However, in practice l propose that teachers construct their lesson plans according to their various spheres of interest.

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The Measurement of Oil Globule Size Distribution in the Soymilk Suspended with the Soybean Particle (대두입자가 분산된 두유에서 기름입자의 입도분포 측정)

  • Chung, J.B.;Yoon, S.K.;Sohn, H.S.
    • Korean Journal of Food Science and Technology
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    • v.22 no.4
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    • pp.369-372
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    • 1990
  • Although the measurement of oil globule size distribution is necessary to detect the process of demulsification, the reasonable methodology for its measurement has not been suggested because the solution of soymilk contains insoluble soybean particle and the protein to interfere with the detection of oil globule or oil content. The oil globule size distribution was measured by the homogeneous suspension and cumulative method under gravitational force or centrifugal force, which were modified with Stokes' low. The geometric mean diameter of oil globules in this soymilk was $033{\mu}m\;and\;031{\mu}m$ under gravitational method and centrifugal method, respectively. The differences of oil globule size distribution in the solutions emulsified by different pressures were detected by this method. The mean diameter of the solutions treated at higher pressure was shifted to smaller size and the distribution pattern of the solutions at higher pressure became more compact around the mean diameter.

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Experimental Study on Effect of Hybrid Quay Wall According to Floating Breakwater (부유식 방파제에 따른 안벽 내 영향에 관한 실험적 연구)

  • Son, Hyok Jun;Cho, Yong-Sik
    • 한국방재학회:학술대회논문집
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    • 2011.02a
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    • pp.53-53
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    • 2011
  • 최근에 세계화, 무역자유화에 따른 컨테이너 물동량이 증가하고 있다. 그에 발맞추어 초대형 컨테이너선이 등장하게 되고 신개념, 고효율의 항만인프라의 도입이 요구되고 있다. 이런 배경에 따라 최근에 국내외에서 부유식 안벽에 관한 기술 개발 및 연구가 더욱 필요한 상황이다. 부유식 안벽은 이동가능한 부유식 구조로 기존 항만의 확장 또는 신규 항만 건설시 환경문제를 최소화하고 기항, 선박수 및 선박의 크기에 따른 안벽 배열을 최적화 할 수 있어 항만 기능을 고도화함으로써 녹색항만을 구현하는데 많은 기여를 하게 될 것이다. 특히 컨테이너선의 양현하역과 환적이 가능하게 되어 컨테이너 터미널의 화물처리능력을 확대할 수 있을 뿐 아니라 기항선박의 체류시간을 최소화 할 수 있는 장점이 있다. 또한, 우리나라는 삼면이 바다로 크고 작은 항만들이 해안선을 따라 위치하고 있다. 이러한 항만들을 안전하게 보호하기 위한 방파제는 항만 기본시설인 외곽시설 중의 가장 중요한 구조물이다. 국내에 설치된 방파제는 대부분 사석이나 케이슨을 이용한 중력식 방파제로써 해저에 고정되어 해수면상으로 건설되므로 항내 외 해수교환을 차단하여 항내 수질악화를 초래할 뿐만 아니라 수심에 따라 막대한 건설비용이 소요된다. 따라서 친환경적이고 경제적인 새로운 형식의 방파제에 대한 연구 및 개발이 필요한 실정이다. 그 중 하나의 대안인 부유식 방파제는 공사기간이 짧고 비교적 수심에 대한 제약이 없는 것이 특징이다. 또한 해수의 원활한 흐름이 가능하기 때문에 중력식 방파제에 비해 경제적이며, 환경적 측면에서 큰 장점이 있다. 하지만 아직까지 부유식 방파제에 대한 국내 및 해외에서의 연구는 이론적인 해석을 중심으로 이루어져 부유식 방파제 실용화를 위한 많은 연구가 수행되어야 할 것으로 판단된다. 본 연구에서는 부유식 안벽 내에서 정온도를 효과적으로 유지하기 위하여 부유식 방파제를 설치하고 소파성능과 부유식 안벽내의 영향성을 수리모형실험을 통해 분석하였다.

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Data Acquisition Method for Marine Geophysical Survey (해양물리탐사 자료취득 기법)

  • Han, Hyun-Chul;Park, Chan-Hong
    • Economic and Environmental Geology
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    • v.39 no.4 s.179
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    • pp.417-426
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    • 2006
  • Data acquisition is as important as data processing and interpretation in the field of marine geophysical exploration. Marine geophysicist, however, may not have enough information in this field because data acquisition method has been mainly developed by the commercial companies manufacturing the equipment. Therefore, the purpose of this paper is to introduce the general data acquisition method and information to help to construct the systematic and effective survey plan. When a survey plan is set up, the most important thing is to select the seismic equipment based on required penetration depth and resolution, and then construct the survey line intervals. Although a line interval varies from the research purposes, it should be narrower than the expected subsurface structures. Also, if 100% coverage of multibeam data is required, line intervals need to be adjusted based on the equipment characteristics. In case of merging with the preexisting dataset like bathymetry, gravity and magnetic, cross-over errors occurred at the each cross point should be removed to avoid any kinds of misinterpretation.

An Analysis on the Impact of Korea-Chile FTA on Busan Port - Focusing on the Inbound Container from Chile - (한-칠레 자유무역협정이 부산항 물동량에 미치는 영향분석 - 대 칠레 수입 컨테이너화물 중심 -)

  • Nam, Kichan;Nam, Hyung-Sik;Kang, Dal-Won
    • Journal of Navigation and Port Research
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    • v.37 no.6
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    • pp.681-687
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    • 2013
  • Free Trade Agreement(FTA) aims at abolishing tariffs on trade among nations or regions resulting in having a significant impact on maritime transportation and port. Korea made the first FTA with Chile in 2004 and the trade volume between two countries has seen significant increase. The literature on such impact, however, seems to be very limited. The main purpose of this study is, therefore, to analyze the impact of Korea-Chile Free Trade Agreement on the imported container throughput from Chile at the Busan Port. For this both cross-sectional and time series data are collected that comprise container throughput, Gross Domestic Product (GDP), import tariff, and maritime freight rate, from 2000 to 2011, and the gravity model is applied. The main result of the study shows that the dependent variables, GDP and import tariff are statistically significant, but the maritime freight rate is not consistent with regarding to statistical significance and parameter sign.

An Empirical Study of the Tradability caused by the Service Characteristics in Korea : Focusing on hard and soft service (한국의 서비스 특성에 따른 교역가능성에 관한 실증 연구 : 하드 서비스와 소프트 서비스의 비교를 중심으로)

  • Choi, Young Jun;Seok, Jun Ho;Hwang, Yoon Seop
    • International Area Studies Review
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    • v.14 no.3
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    • pp.109-130
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    • 2010
  • The service sector comprises two thirds of world GDP in 2005 and takes 20% of the world trade. As the technologies such as telecommunication technologies advance, the long-distance trades in services is expected to increase. But there are few empirical research on the flows of services between regions. This paper studies the pattern of flows of long-distance trades in services across the regions. Since it is very hard to collect reliable data on long-distance trade in services, we collect data from regional input-output tables of Korea. The results shows that the hard service which can be consumed spatially separated from production tends to have more long-distance trade than the soft service which is consumed simultaneously with production. It also shows that regional gross domestic production is important factor for the pattern of trades in services.

Structural Changes in the Korean Inter-City Passenger Flows Caused by Time-Distance Changes: Based on the Passengers of Express Bus and Railroad Systems (시간거리 변화에 따른 한국 도시간 통행흐름의 구조 변화: 고속버스와 철도 이용객을 중심으로)

  • Jeong, Mi Seon;Lee, Keumsook
    • Journal of the Korean Geographical Society
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    • v.50 no.5
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    • pp.527-541
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    • 2015
  • The purpose of this study is to investigate the changes in the inter-city passenger flows since adapting the express rail system in Korea(KTX). For the purpose, we analyze the express bus and rail passenger annual flow data of the before and after adapting KTX. In first, we examine the changes in the time-distance parameters in the inter-city passenger flows of the express bus, general rail, and KTX by applying gravity model. The results reveal that express bus passenger flows are less sensible to the time-distance compare to the rail passenger flows, and the trends have been intensified over time. However, the time-distance parameters for the KTX passenger flows reveal the reverse relationships with the gravity model. The KTX passenger flows expand between the long distance cities. We also apply the MST(Maximum Spanning Tree) method to find out the spatial structural changes in the inter-city passenger flows. The number of hierarchies has been increased in the express bus and general rail passenger flows, while single hierarchical structure has been lasted in the KTX passenger flows.

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Spherical Slepian Harmonic Expression of the Crustal Magnetic Vector and Its Gradient Components (구면 스레피안 함수로 표현된 지각 자기이상값과 구배 성분)

  • Kim, Hyung Rae
    • Economic and Environmental Geology
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    • v.49 no.4
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    • pp.269-280
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    • 2016
  • I presented three vector crustal magnetic anomaly components and six gradients by using spherical Slepian functions over the cap area of $20^{\circ}$ of radius centered on the South Pole. The Swarm mission, launched by European Space Agency(ESA) in November of 2013, was planned to put three satellites into the low-Earth orbits, two in parallel in East-West direction and one in cross-over of the higher altitude. This orbit configuration will make the gradient measurements possible in North-South direction, vertical direction, as well as E-W direction. The gravity satellites, such as GRACE and GOCE, have already implemented their gradient measurements for recovering the accurate gravity of the Earth and its temporal variation due to mass changes on the subsurface. However, the magnetic gradients have little been applied since Swarm launched. A localized magnetic modeling method is useful in taking an account for a region where data availability was limited or of interest was special. In particular, computation to get the localized solutions is much more efficient and it has an advantage of presenting high frequency anomaly features with numbers of solutions fewer than the global ones. Besides, these localized basis functions that were done by a linear transformation of the spherical harmonic functions, are orthogonal so that they can be used for power spectrum analysis by transforming the global spherical harmonic coefficients. I anticipate in scientific and technical progress in the localized modeling with the gradient measurements from Swarm and here will do discussion on the results of the localized solution to represent the three vector and six gradient anomalies over the Antarctic area from the synthetic data derived from a global solution of the spherical harmonics for the crustal magnetic anomalies of Swarm measurements.

A Study on the Evaluation for the Improvement of the Functional Movement of Women′s Wear -with Concentration on the Measurement of Functional Movement according to the Change of Cap Height- (여성복의 기능성 향상을 위한 착의 평가에 관한 연구 -소매산 높이 변화에 따른 기능성 측정을 중심으로-)

  • 박선경
    • The Research Journal of the Costume Culture
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    • v.12 no.2
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    • pp.249-261
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    • 2004
  • This research proves the ROM method (Range Of Motion), which has already been used in other countries, that measures the capacity of exercise and the adaptation of movement of functional garments for special purpose due to change of the height of basic sleeve sloper. Basically, the ultimate goal of the research is to improve the functional pattern design. Firstly, this research proves the proper application of ROM that is used for the evaluation of fitting test. Therefore, according to this research, the company is able to produce the sample that is appropriate to the various purpose for women garments and betters the evaluation of function of garments. Moreover, it suggests that the evaluation of fitting test satisfies the consumers who desire to try better garments and contributes to the competitions among the companies that bring more improvements to the fashion design.

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Study on Gravitational Torque Estimation and Compensation in Electrically Driven Satellite Antenna System (전기식으로 구동하는 위성안테나 시스템의 중력토크 추정 및 보상에 관한 연구)

  • Kim, Gwang Tae
    • Journal of the Korean Society for Precision Engineering
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    • v.33 no.10
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    • pp.789-796
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    • 2016
  • The weight of an antenna system pointing satellite on the mobile platform is restricted by the weight limit of the mobile platform. The maximum power of the actuator driving the antenna system is thus limited because a high power actuator needs a heavier weight. Thus, a drive system is designed to have a low torque requirement by reducing the gravitational torque depending on gravity or acceleration of the mobile platform, including vibration, shock, and accelerated motion. To reduce the gravitational torque, the mathematical model of the gravitational torque is preferentially obtained. However, the method to directly estimate the mathematical model in an antenna system has not previously been reported. In this paper, a method is proposed to estimate the gravitational torque as a mathematical model in the antenna system. Additionally, a method is also proposed to calculate the optimal weight of the balancing weight to compensate for the gravitational torque.