• 제목/요약/키워드: preserve

검색결과 2,265건 처리시간 0.026초

Aquatic Biodiversity of the 6 main lakes of Hanoi city and the necessity of its conservation

  • Yen Mai Dinh
    • 한국생태학회:학술대회논문집
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    • 한국생태학회 1999년도 국제 Symposium 및 '99 춘계 공동 학술 발표대회
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    • pp.43-54
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    • 1999
  • 1. Hanoi city was built up on the wetland landscape of the Red River delta therefore it has a network of many lakes and rivers. 2. The aquatic biodiversity (Macrophytes, Invertebrates, Fishes, Vertebrates) of the 6 main lakes (Ho Tay, Hoan Kiem, Bay Mau, Giang Vo, Dong Da, Thanh Nhan) are rich and diverse. It represents the patterns of Red River delta one's. Many rare and endangered species are found in these lakes Particularly a giant freshwater turtle species in Hoan Kiem lake. 3. All of these lakes are more or less polluted. Their environments are seriously degrading both in water quality and aquatic biodiversity. 4. Based on socio-economical and cultural role of these lakes of Hanoi city, it is very necessary to preserve and to restore their environments and aquatic biodiversity: water Pollution control, landscape planning, making roads around the lakes and erosion control for their banks, legislation measures, rational exploitation of aquatic biodiversity, restoration the artificial wetlands with macrophytes.

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Long-term survival of retained deciduous mandibular second molars and maxillary canine incorporated into final occlusion

  • Hwang, Soonshin;Choi, Yoon Jeong;Chung, Chooryung J.;Kim, Kyung-Ho
    • 대한치과교정학회지
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    • 제47권5호
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    • pp.323-333
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    • 2017
  • Orthodontic treatment of a complex case that involves retained deciduous mandibular second molars with missing permanent successors is challenging. Usually, congenitally missing teeth are manifested with other dental anomalies that further complicate orthodontic treatment, such as retained deciduous teeth, impactions, transpositions and peg-shaped lateral incisors. Even though the long term prognosis of the retained deciduous tooth is not fully predictable, if the teeth are in good condition, the patient and clinician may incline towards a decision to preserve the deciduous teeth as long as possible. This case report demonstrates that deciduous teeth, in this case the mandibular second molars and maxillary canine, can be incorporated into final occlusion with clinically stable long-term results.

우주발사 시스템 개발을 위한 통합 기술관리 시스템 소개 (Introduction of Program Life-Cycle Management System for Space Launch System Development)

  • 조미옥;조철훈;이준호;오범석;박정주;조광래
    • 시스템엔지니어링워크숍
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    • 통권4호
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    • pp.86-89
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    • 2004
  • A web-based program life-cycle management(PLM) system is introduced to implement the system engineering processes and to provide the development teaceability online. This information system aims for the realization of essential system engineering management techniques currently applied to the space launch system development program including management of configuration and data based on the work breakdown structure(WBS), WBS, bill of materials and properties. The system enhances communication and gives access to the development data with relevant information such as data-to-data relation and approval status/history through the web, and preserve all of the development data throughout the program life-cycle. Further improvement of the system is planned to implement the program managrment pricesses and to provide integrated information useful for the programmatic decision making.

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인산염 매몰재 Special Liquid의 온도변화에 따른 Margin 적합도 (The Margin Fitness under the Variation of Temperature of Phosphate Bonded Investment's Special Liquid)

  • 김은숙
    • 대한치과기공학회지
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    • 제13권1호
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    • pp.5-8
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    • 1991
  • There are many factors influence on the margin fitness of Casting body. Among them, I intend to examine the influence of the gap of temperature of investment's special liguid. As the result of investing and experiment of the whole of eighty copings under the classification the temperature of liquid into four groups 0$^{\circ}C$, 10$^{\circ}C$, 20$^{\circ}C$, 30$^{\circ}C$ I came to the conclusion as following. 1. The margin fitness of these four groups, as the result of examination with microscope, was the most accurate at 20$^{\circ}C$ was less aceurate in order of 30$^{\circ}C$, 10$^{\circ}C$, 0$^{\circ}C$. 2. directions is the way to preserve the most exact margin fitness.

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A 2.4 GHz 802.11b Throughput Estimation In a Noisy Environment Using an Experimental Noise Parameter

  • Hur Min-Ho;Lim Sung-Jin;Kwon Sewoong;Yoon Young-Joong
    • Journal of electromagnetic engineering and science
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    • 제5권2호
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    • pp.61-65
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    • 2005
  • In this paper, a numerical permissible disturbance model is proposed to preserve a throughput performance of a 2.4 GHz wireless LAN service. The model is composed of two parameters, a peak value and a time rate of noise signal. The model parameters are experimentally determined from an APD parameter measurement. The APD parameter is measured by using the APD measurement method which is recommended from CISPR/A/447/CD.

MB-OFDM UWB 를 위한 RS 복호기 설계 (A Design of RS Decoder for MB-OFDM UWB)

  • 최성우;신철호;최상성
    • 한국전자파학회:학술대회논문집
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    • 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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    • pp.131-136
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    • 2005
  • UWB is the most spotlighted wireless technology that transmits data at very high rates using low power over a wide spectrum of frequency band. UWB technology makes it possible to transmit data at rate over 100Mbps within 10 meters. To preserve important header information, MB-OFDM UWB adopts Reed-Solomon(23,17) code. In receiver, RS decoder needs high speed and low latency using efficient hardware. In this paper, we suggest the architecture of RS decoder for MB-OFDM UWB. We adopts Modified-Euclidean algorithm for key equation solver block which is most complex in area. We suggest pipelined processing cell for this block and show the detailed architecture of syndrome, Chien search and Forney algorithm block. At last, we show the hardware implementation results of RS decoder for ASIC implementation.

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알칼리부여제의 회복성능에 관한 기초적 연구 (The experimental study on the recovery faculty for impregnation alkalization agent)

  • 김광기;박선길;임남기;정재영;송병창;정상진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2002년도 학술논문발표회
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    • pp.61-64
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    • 2002
  • The present age, it takes an interest in maintenance and preserve of the aged constructive materials cause destruction of environmental reason and a loss of resource. As answering question given to candidates at a civil examination, it is carbonated concrete construction materials to give alkalization agent to seek the plan to be extended durable life. The representative material, it was known for a chemical compound of alkailzation-Silica acid with Lithium and also used on inside and outside the country. But, it is so difficult to decide the effect because the work is to be repeated for a processing of construction. So, in this study, to investigate recovery faculty on a period of incubation that restrain processing of carbonation by impregnation alkalization agent, we were made good progress from basic test through comparative and analysis at laboratory and the spot of construction.

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Investigation of the Incorporation Efficiency of $\beta$-Carotene into Liposomes

  • Rhim, Chae-Hwan;Lee, Kyong-Eun;Yuk, Hyun-Gyun;Lee, Sang-Chun;Lee, Seung-Cheol
    • Preventive Nutrition and Food Science
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    • 제5권3호
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    • pp.177-178
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    • 2000
  • Chemical and photochemical precesses during food storage an preparation rapidly degrade $\beta$-carotene, the most active form of carotenoids. We investigated the possibility of liposomes as tool to preserve $\beta$-carotene. Liposomes with $\beta$-carotene were prepared as multilamellar vesicles by using soybean phosphatidylcholine, in terms of the ratio of $\beta$-carotene to phospholipid and pH. Incorporated efficiency was 99.7% at 1:0.05 of phospholipid : $\beta$-carotene and at pH 9.0. As the concentration of $\beta$-carotene increased, the incorporated efficiency increased progressively. pH did not affect the incorporation efficiency greatly.

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BOOLEAN RANK INEQUALITIES AND THEIR EXTREME PRESERVERS

  • Song, Seok-Zun;Kang, Mun-Hwan
    • Journal of applied mathematics & informatics
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    • 제29권5_6호
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    • pp.1525-1532
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    • 2011
  • The $m{\times}n$ Boolean matrix A is said to be of Boolean rank r if there exist $m{\times}r$ Boolean matrix B and $r{\times}n$ Boolean matrix C such that A = BC and r is the smallest positive integer that such a factorization exists. We consider the the sets of matrix ordered pairs which satisfy extremal properties with respect to Boolean rank inequalities of matrices over nonbinary Boolean algebra. We characterize linear operators that preserve these sets of matrix ordered pairs as the form of $T(X)=PXP^T$ with some permutation matrix P.

F.A.M.을 이용한 공동 내부의 유동해석 (Analysis of Flow Field in Cavity Using Finite Analytic Method)

  • 박명규;정정환;김동진
    • Journal of Advanced Marine Engineering and Technology
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    • 제15권4호
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    • pp.46-53
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    • 1991
  • In the present study, Navier-Stokes equation is numerically solved by use of a Finite analytic method to obtain the 2-dimensional flow field in the square cavity. The basic idea of F.A.M. is the incorporation of local analytic solutions in the numerical solution of linear or non-linear partial differential equations. In the F.A.M., the total problem is subdivided into a number of all elements. The local analytic solution is obtained for the small element in which the governing equation, if non-linear, to be linearized. The local analytic solutions are then expressed in algebraic form and are overlapped to cover the entire region of the problem. The assembly of these local analytic solutions, which still preserve the overall nonlinearity of the governing equations, results in a system of linear algebraic equations. The system of algebraic equations is then solved to provide the numerical solutions of the total problem. The computed flow field shows the same characteristics to physical concept of flow phenomena.

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