• 제목/요약/키워드: well-mixed area

검색결과 270건 처리시간 0.031초

조장조성용 포러스콘크리트의 생물부착 특성에 관한 실험적 연구 (An Experiment Study of Porous concrete for oceanic life Adhesion in Sea-water Environment)

  • 박승범;서대석;김봉균;이병재;조광연
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.598-601
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    • 2006
  • The Purpose of this study is to develope the method for early recovery of the biodiversity in the oligotrophical costal area, it is important in the recovery of the biodiversity to make kelp forest grow in the concerned area. In order for it, sufficient nutrient is required as well as the proper seedbed, Hence in this study, granulated fertilizer, which contains nutrient, such as nitrogen, phosphorus and etc, is coated by cement paste, and then is mixed in to the porous concrete in order to provide seedbed and nutrient simultaneously. As a result of examination of growth property of marine plants of multiple performance concrete for kelp forest regeneration, seaweeds is adhered plentifully when the number of days is longer. when the granular fertilizer mixed. adherence and growth of marine plants is excellent and is stabilized over the long run. In case 6 month of the number of days immersed, marine plants and growth will appear.

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하악골에 발생된 법랑모치아종 (AMELOBLASTIC ODONTOMA OCCURRED IN THE MANDIBLE)

  • 하쌍용;송남규;고광준
    • 치과방사선
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    • 제26권2호
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    • pp.181-189
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    • 1996
  • Ameloblastic odontoma is a mixed odontogenic tumor, which is characterized as being extremely rare, displaying aggressive clinical behavior, resembling a mixed radiopaque and radiolucent radiographic appearance and containing both ameloblastoma and a composite odontoma. Seven-year-old boy complaining of delayed eruption of the left lower permanent 1st molar came to the department of Oral & Maxillofacial Radiology at Chonbuk National University Hospital. The list of our radiographic differential diagnosis included the dental follicle, compound odontoma, complex odontoma and cystic odontoma. The microscopic analysis showed the lesion with the characteristics of an ameloblastic odontoma. The obtained results were as follows; 1. The area was asymptomatic, but the delayed eruption of the left lower permanent 1st molar was observed. Radiographically, well-defined widened pericoronal radiolucency containing several tooth-like radiopacities involving the impacted left lower permanent 1st molar and well-defined round radiolucency containing irregular radiopaque mass were observed. 3. Histopathologically, several tooth-like structures, odontoma components with the area of typical enamel, dentin and pulp, and ameloblastic components with typical follicular ameloblastoma were observed.

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무인항공기용 천음속 사류형 압축기의 공력 설계 (A Study on Aerodynamic Design of a Transonic Mixed-Flow Compressor for UAV)

  • 최재호
    • 한국군사과학기술학회지
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    • 제11권2호
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    • pp.152-160
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    • 2008
  • In the present paper, a transonic mixed-flow compressor that has relatively lower frontal area than that of centrifugal compressors is discussed, and aerodynamic design as well as performance prediction are performed. Main design constraints are compressor exit Mach number of 0.3 and flow angle of 30degrees at the design point, and maximum overall compressor diameter of 177mm, that is 7.0inch. The mass flow rate of design point and pressure ratio are 1.05kg/s and 5.2:1, respectively. The aerodynamic design results show that the transonic compressor designed with forward-swept inducer and curved diffuser can have the target performance with efficiency of 75% within the given constraints. And the compressor exit flow characteristics are discussed here.

Dynamic Channel Allocation of WiMedia UWB MAC Protocol Supporting Mixed HD Video Data and Shipboard Control Data with Link Parameter Optimization

  • Lee, Yeonwoo
    • International Journal of Internet, Broadcasting and Communication
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    • 제8권4호
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    • pp.1-10
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    • 2016
  • This paper considers WiMedia UWB network based wireless ship area network (WSAN) so as to support high-quality multimedia video data services and important shipboard control data. In this paper, prioritized contention access (PCA) and distributed reservation protocol (DRP) based on WiMedia UWB (ECMA-368) MAC protocols are combined and proposed to support mixed high-quality video traffic and shipboard control data traffic applying varying DRP and PCA data periods according to channel condition and link parameter ptimization. It is shown that the proposed dynmaic channel allocation of WiMedia UWB MAC protocol can provide reliable mixed video and shipboard control data traffic as well.

Mixed Driving 방식을 이용한 QVGA급 LDI의 Source Driver 설계 (Design of Source Driver for QVGA-Scale LDI Using Mixed Driving Method)

  • 김학윤;고영근;이성우;최호용
    • 대한전자공학회논문지SD
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    • 제46권11호
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    • pp.40-47
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    • 2009
  • 본 논문에서는 mixed driving 방식을 이용하고 이미지 개선을 위해 $\gamma$-correction을 수행하는 QVGA급 TFT-LCD driver IC의 Source Driver를 설계한다. 240 RGB ${\times}$ 320 dots resolution을 가진 source driver는 720개의 채널을 통해 TFT-LCD 패널을 구동하고 18-bit의 RGB 데이터를 사용하여 26만 color를 수행한다. Mixed driving 방식은 종전의 좋은 구동력을 가진 channel amp. driving 방식에 저면적이 가능한 gray amp. driving 방식을 혼합한 방식으로서, 영상이 동일 색상을 가지는 worst case를 감지하여 구동력을 높여주는 방식을 사용함으로써 적절한 구동력과 저면적을 구현하는 설계방식이다. 본 Source Driver는 $0.35{\mu}m$ Magnachip embedded DRAM 공정을 사용하여 설계하였으며 Hspice를 사용하여 시뮬레이션을 하였다. 실험결과, 기존의 gayscale driving 방식에서는 hsync time을 만족시키지 못하는데 비해 $17{\mu}s$의 channel 구동시간으로 충분한 timing margin을 가지고 액정 channel 을 구동할 수 있으면서, 구동 앰프 78개와 제어회로를 갖는 저면적으로 설계되었다.

북동태평양(KODOS 해역)의 영양염 및 형광 유기물에 관한 환경특성 연구 (Environmental Characteristics of Nutrients and Fluorescent Organic Hatters in the Northeast Pacific Ocean(KODOS))

  • 손승규;박용철
    • 한국환경과학회지
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    • 제6권6호
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    • pp.595-604
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    • 1997
  • To investigate characteristics of biogeochemical environment of the Korea Deep Ocean Study(KODOSI area in the northeast Pacific Ocean, we preferentially measured Inorganic nutrients and fluorescent organic matters. Typically. the permanent thermocline was well developed at the depth of 200~1000m In the study area. Nitrate. phosphate and silicate were low In the surface mixed layer and Increased with depth. N/P and N/Si showed 15 and 0.2 respectively In the deeper layer. Two fluorophores, biomacromolecule(protein-like) and geomacromolecule (humid-like) , were observed by three dimensional fluorescence excltatlon/ emission spectra matrix. Biomacromolecule(maximum fluorescence at $Ex_{280m}/Em_{330nm}$) ranged from 41.9 to 147.0 TU with its maximum In the surface mixed layer and minimum in deeper water, This is a same trend that has been reported for DOC in the equatorial Pacific. This suggests that biomacromolecule might be labile and converted to refractory humic substance after bacterial degradation In the deeper layer. On the contrary, geomacromolecule(maximum fluorescence at $Ex_{330m}/Em_{430m}$), ranged from 7.6 to 46.5 QSU, showed minimum in the surface nixed layer(euphotic zone) Implying photodegradation and then increased with depth at all stations. In the characteristics of vertical profiles, the relationship between biomacromolecule and geomacromolecule showed negative correlation. Such trend can be attributed to biochemical regeneration or formation of fluorescent materials accompanying oxidation and rennnerallzation of settling organic matter.

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우편집중국 소포구분 작업장 인력계측 수립모형 (Workforce Planning Model for the Parcel Sorting Area in a Mail Processing Center)

  • 박철순;배성문;차병철;차춘남
    • 산업경영시스템학회지
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    • 제32권3호
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    • pp.1-9
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    • 2009
  • Processing mail objects in a mail processing center involves several steps and operations, in particular dispatching as well as sorting by destination. The purpose of this paper is to present a model for the part-time worker staffing and allocation problem as it arises at the parcel sorting area in a mail processing center. The problem is formulated as a mixed integer linear program model to minimize the variable part-time workforce related cost. Hot only the characteristics of the sorting operations but also the dispatching requirements of the vehicles are reflected into the model. Six example problems with three different daily amounts of arriving mail are solved with LINGO to demonstrate the effectiveness of the 7-level induction option for the parcel sorting machine over the current 3-level one. The results indicate that measurable savings can be achieved by departing from current practice.

시간대 및 구역의존 차량이동속도를 고려하는 다목적차량일정문제: 일정계획해법과 전문가시스템 (Multiobjective Vehicle Scheduling Problem with Time and Area-Dependent Travel Speeds: Scheduling Algorithm and Expert System)

  • 박양병
    • 대한산업공학회지
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    • 제23권4호
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    • pp.621-633
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    • 1997
  • This paper is concerned with the multiobjective vehicle scheduling problem with time and area-dependent travel speeds(MVSPTD), in which two conflicting objectives are explicitly treated and the travel speed between two locations depends on the passing area and time of day. The two objectives are the minimization of total vehicle travel time and the minimization of total weighted tardiness. First, I construct a mixed integer linear programming formulation of the MVSPTD, and present o heuristic algorithm that builds the vehicle schedules based on the savings computed. The results of computational experiments showed that the heuristic performs very well. Finally, I propose an expert system for vehicle scheduling in the MVSPTD. Its whole process is executed under VP-Expert expert system environment.

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제주도 특급관광호텔의 공공부분 평면구성에 관한 연구 (A Study on the Plan Composition of Public Part of the Luxury Resort Hotels in Jeju-Do)

  • 박철민;김학진
    • 한국실내디자인학회논문집
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    • 제38호
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    • pp.153-163
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    • 2003
  • In order to overcome such limits of hotel sales, the role of hotel public section, such as eating and drinking facilities, is very important. Moreover, city hotels increase the value of public section by providing various event for citizens as well as and services for banquet. Since Jeju has urban hotels and resort hotels mixed together, their Plane types and area composition based on the characters of customers using the public section are different from ones of other cities. The purpose of this study is to provide basic material for the qualify improvement of the luxury resort hotels in Jeju. We examine the tendency of the systematic Plane composition of the Public sections which take different types of customers, such as Jeju people and tourists, into consideration, analyzing the plane types and the area composition of the luxury resort hotels in Jeju. The study shows that the public part of hotels always had great impact on hotels sales depending on the compositions of plane and area.

Studies on Pyrolysis Behaviour of Banana Stem as Precursor for Porous Carbons

  • Manocha, Satish;Bhagat, Jignesh H.;Manocha, Lalit M.
    • Carbon letters
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    • 제2권2호
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    • pp.91-98
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    • 2001
  • Porous carbons have been prepared from different parts of banana stems using two different routes, viz., by pyrolysing the mass at different temperatures as well as by treating the dried mass with chemicals followed by pyrolysis. The pyrolysis behaviour of all these materials has been studied up to $1000^{\circ}C$. Samples treated with acids exhibit more increase in surface area as compared to those treated with alkalies or salts. Analysis of BET surface area shows that the carbon prepared at low temperature shows mixed porosity, i.e., micro and mesopores. Samples heated to high temperature above $700^{\circ}C$ show decrease in macroporosity and increase in microporosity. Liquid adsorption studies have been made using methylene blue and heavy oil. The activated carbons so prepared exhibit higher oil adsorption mainly in the macro and mesopores.

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