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Distribution and Characteristics of Plant Resources of Native Pyrus sp.

  • Ahn, Young-Hee
    • Plant Resources
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    • v.4 no.3
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    • pp.157-160
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    • 2001
  • The wild Pyrus plants belong to the deciduous woody plants in Rosaceae family. Most are cultivated for fruit productions, but some for ornamental plants. There are 5 Pyrus species including Pyrus ussuriensis and 8 varieties cultivated in Korea. In Korea, these plants are populated near villages or on the hills, and they are easily propagated since their fruit are very juicy and quite big in size. Plant breeding to get improved cultivars is not difficult because the Pyrus plants are easy to cross breeding among its genus. Because not only this reason but there have been shown lots of variation in wild groups, the Pyrus plants inhabited in Korea are excellent deciduous woody plants and favorable fruit trees to develop ornamental plants. It is necessary to develop many kinds of fruit trees and ornamental trees containing genetically different character, so that it will be satisfied for many different people's taste and demands. Collecting lots of wild plant resource with diverse genes is necessary for plant breeding.

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The Methods of Rail Joint Detection and Gap Signal Compensation for Levitation Control of Urban Maglev (도시형 자기부상열차 부상제어를 위한 궤도 이음매 검출 및 공극 신호의 보상 방법)

  • Kim, Haeng-Koo;Lee, Jong-Min;Kang, Byung-Kwan;Kim, Kuk-Jin;Kim, Chun-Kyung
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.922-927
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    • 2007
  • The present urban maglev which has been developed in Korea is controlled by 4-edge control method over each bogie. The control output which is derived from two gap sensors and one vertical acceleration sensor controls magnet to maintain a nominal gap. But, the gap signal acts as a big disturbance in rail joint though two gap sensors are used and finally result in unstable response and poor ride comfort. This paper treats of a method to compensate the gap signal in rail joint for the levitation control of urban maglev. The physically abnormal change of gap is detected when one gap sensor passes a rail joint, the disturbance of gap in rail joint is estimated. Finally the disturbance in gap signal is eliminated by processing the information of vehicle speed and estimated disturbance in when the other gap sensor passes a rail joint.

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Study on the Performance Analysis of Solar Heating System with Cloud Cover (운량에 따른 태양열 시스템의 성능 분석에 관한 연구)

  • Kim, Won-Seok;Pyo, Jong-Hyun;Cho, Hong-Hyun;Ryu, Nam-Jin
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.1215-1219
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    • 2009
  • In this study, the performance of solar assisted hybrid heat pump system with cloud cover were analyzed by using experimental method in spring season. It was consisted of concentric evacuated tube solar collector, heat medium tank, heat storage tank, heat pump, and so on. As a result, the solar radiation should be maintained over $4.1\;MJ/m^2$ in order to operate solar heating system for heating. Solar heat of collector wasn't affected by ambient temperature, but cloud cover has a big effect to collector efficiency. In addition, the collector efficiency is about 50-60%, and solar fraction is 40% for this system.

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A Study on the Walking Time to Drop off Parcels on the Design of VRP Heuristic for Parcel Delivery Services (택배배송 VRP 해법 설계를 위한 도보전달소요시간에 대한 연구)

  • Park, Sung-Mee;Moon, Gee-Ju
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.35 no.2
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    • pp.189-195
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    • 2012
  • Parcel delivery services are a bit different from general vehicle routing problems since the services require a deliver's walking time to give the parcel to the customer. This time takes more than 1/4 of total delivery time, but it is ignored for the convenience of algorithm design in general. The walking time is too big to be ignored if we need to estimate necessary delivery time precisely as much as possible, or to design a heuristic with varying vehicle moving speeds in metropolitan area. For these reasons, the walking times are surveyed and analyzed to use on the design of VRP heuristic for parcel delivery services in this research.

Improvement of Fire Resistance and Impact Sound Insulation Performance for Timber Framed Floor by Installation of Isolated Ceiling (분리된 천정의 설치를 통한 목구조 바닥의 내화성능 및 충격음 차단성능 향상)

  • Park, Joo-Saeng;Kim, Se-Jong;Lee, Sang-Joon
    • Journal of the Korea Furniture Society
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    • v.24 no.4
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    • pp.426-432
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    • 2013
  • Fire resistance and impact sound insulation tests were performed for a floor assembly, of which stiffness was reinforced by shortening the span of floor joists by installing glulam beam additionally in the middle or one thirds of the original span, and which an additional ceiling component was installed apart from floor structure. By applying the isolated ceiling, timber framed floor showed 1 hour of fire resistance even in case that dead load was increased by considering cement mortar layer for radiant floor heating. Insulation performance against light and heavy impact sound was improved significantly by applying the sound absorbing layer of big mass and high elasticity in addition to the stiffness improvement and isolated ceiling.

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Investigation on Transient Vibration of Piping System to Heater in a Power Plant (발전소 가열기 급수용 배관계 이상 진동 고찰)

  • 양경현;조철환;배춘희
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.05a
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    • pp.975-978
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    • 2004
  • There was transient vibration on the piping system from #4 heater to the deaerator in a power plant. We found it was resulted from resonance between the natural vibration of the piping system and vibration induced by flow of feedwater. We verified it would reduce vibration by increasing stiffness of the piping system. Therefore we concluded that it would be generally better to increase stiffness of the piping system to reduce vibration amplitude of 10Hz low for big sized piping systems.

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Recent Advances of Osseointegrated Implants Removal (골유착된 임프란트 제거의 최신지견)

  • Kim, Nam Yoon
    • The Journal of the Korean dental association
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    • v.54 no.4
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    • pp.258-273
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    • 2016
  • In spite of appropriate treatment of peri-implantitis, the peri-implant bone loss was keep going, the clinician should remove the osseointegrated implant. the conventional methods are like a extraction of natural teeth, and use of trephine drills. In these days, many exclusive instruments are invented by implant companies. these instruments can make easy, least invasive, less traumatic removal of osseointegrated implants. In generally peri-implant bone loss progress steadily less sign and symptoms that the patient do not want to remove their implants. However, the failure of dental implant is big burden to clinicians and also patients. In the dental implant treatment, there is no 'failure' but only is 'replacement' or 'change'.

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A Survey Study on the Educational Program of Food Preparation in Elementary School in Incheon Area (인천지역 국민학교 식생활 실습단원의 교육실태에 관한 연구)

  • 전영숙;홍성야
    • Journal of Korean Home Economics Education Association
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    • v.7 no.1
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    • pp.121-131
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    • 1995
  • This article is the result of the investigation on the actual condition of food preparation program carried out in elementary schools. Food preparation program belongs to the subject of ‘Shilgwa(Practice)’at elementary level. Though the result shows that instructors have no big problem in teaching theoretical part of the program, it is seriously doubtful whether students can acquire any scientifically practical knowledge which is able to be got through ‘practice’Only 4% of the investigated schools have cooking rooms, and even they have only very few cooking utensils or instruments. In spite of the importance of children’s earlier initiation into food preparation program, most schools are very poorly facilitated for education the program.

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Comparison of Measured and Predicted Daylight Illuminances in Two Underground Spaces

  • Kim, Kang Soo;Paek, Seung Yeob;Kim, Han Seong
    • Architectural research
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    • v.4 no.1
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    • pp.17-23
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    • 2002
  • Daylight simulation methods play an important role for the prediction of daylight illuminances in underground spaces. This daylighting project is designed to compare daylight prediction methods for the application of large underground spaces. In this study, actual measurements were conducted under overcast and clear sky conditions. Also, computer simulations by Radiance, Superlite IEA 2.0 program and scale model testings were conducted to be compared with measured data. Simulation results show the data by Radiance, Superlite IEA 2.0 and the scale model are similar to the measured data in two underground spaces in Seoul. Overall results show that Radiance and superlite IEA 2.0 proved to be useful to predict daylight illuminances even in big underground spaces.

Clinical Report of Insamyangwitang in Hyungsang medicine (인삼양위탕(人蔘養胃湯)의 임상활용(臨床活用)에 대(對)한 형상의학적(形象醫學的) 고찰(考察))

  • Park Chan-Ki
    • Herbal Formula Science
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    • v.11 no.1
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    • pp.205-216
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    • 2003
  • A general review is made on Insamyangwitang(人蔘養胃湯). Following conclusions are drawn from the clinical cases of Insamyangwitang in Hyungsang medicine. 1. Insamyangwitang is composed of four different prescriptions of Huisaentang, Sakoonjatang, Eajintang and Pyungwisan. Huisaentang is usually prescribed for the intestinal convulsion. Sakoonjatang for the deficiency of Ki. Eajintang for retention of phlegm. 2. Insamyangwitang is effective in strengthening the spleen, drying the dampness, warning the middle-warmer to stop vomiting, regulating the flow of Ki, and eliminating phlegm. 3. Insamyangwitang is applicable to malaria caused by cold, intestinal convulsion, abdominal mass, edema, tympanites, Yin syndrome of exogenous febrile disease, distension, lack of appetite, stomachache, and diarrhea. 4. Persons with the following characteristic in Hyungsang are more susceptible to Insamyangwitang : Jung type, Hyul type, fish type, Taium meridian type, white fat damp constitution, person with big mouth, and woman rather than man.

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