• Title/Summary/Keyword: elimination condition

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A Study on Improvement of Inhalation Efficiency of Hood in Ventilation System for Elimination of Industrial Dust (산업용 분진 제거를 위한 배기장치 내 후드의 흡입성능 개선에 관한 연구)

  • Yang, Ho-Dong;Oh, Yool-Kwon
    • Journal of the Korean Society of Safety
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    • v.23 no.2
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    • pp.1-6
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    • 2008
  • The present study investigates on improvement of inhalation efficiency of hood in ventilation system for elimination of industrial dust. The hood, one of local exhaust ventilation system, has an important function to inhale a pollution source such as harmful dust and industrial waste. In this study, in order to improve the inhalation efficiency of the industrial hood, a new device named "gas-guide-device" was attached to inside of hood. The thermal fluid commercial code "Phoenics ver 3.1" was used to analyze the flow velocity distribution at the hood inlet and around the hood after gas-guide-device was installed. And the flow velocity on each position inside and around the hood was actually measured using the hot wire type anemometer under the same condition as that of numerical analysis. Also, in order to identify the optimum shape of gas-guide-device, numerical analysis and experiments are performed under various conditions and their results are presented. The results of this study revealed that the hood attached with gas-guide-device was higher the inhalation efficiency than that for without one and can be possible to improve the capture velocity of the industrial dust. And the optimum shape of gas-guide-device was identified that the ratio of two sizes of gas-guide-device, X to Y, has 4 to 6 on the basis of the hood size in use and the width (b) of gas-guide-device.

Design of Jitter elimination controller for concealing interarrival packet delay variation in VoIP Network (VoIP 네트웍에서 패킷 전송지연시간 변이현상을 없애주는 적응식 변이 제어기 제안 및 성능분석)

  • 정윤찬;조한민
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.12C
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    • pp.199-207
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    • 2001
  • We propose an adaptive shaping controller equipped with the technologies of shaping and buffering VoIP packets arriving at the receiving end by the CAM-type controller. In order to conceal interarrival packet delay variation, the conventional jitter buffers force them to be too large, thereby causing the audio quality to suffer excessive delay. However, by using our proposed method, the delay caused by shaping operation dynamically increases or decreases on the level of jitter that exists with in the IP network. This makes the delay accommodates adaptively the network jitter condition. The less jitter network has the fewer delay the shaping controller requires for jitter elimination. And the CAM-type method generally makes the shaping operation faster and leads to processing packets in as little time as can. We analyse the packet loss and delay performance dependency on the average talk ratio and the number of jitter buffer entries in shaping controller. Surprising, we show that the average delay using our shaping controller is about 70msec. This performance is much better than with the delay equalization method which forces the receiving end to delay about 60msec.

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A Study on the Dry Cleaning of Aluminium Surfaces by Low Temperature Plasma Process (저온 플라스마 공정을 이용한 알루미늄 표면의 건식 세정에 관한 연구)

  • Lim, Gyeong-Taek;Kim, Kyung Hwan;Kim, Kyung Seok;Li, Hui Jie;Song, Sun Jung;Shon, Hokyong;Cho, Dong Lyun
    • Applied Chemistry for Engineering
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    • v.19 no.6
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    • pp.640-644
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    • 2008
  • Lubricating oil on aluminium surfaces was cleaned by a low temperature plasma process. Oxygen plasma mixed with argon was used, and process parameters were the mixing ratio of argon in oxygen, discharge power, and negative DC potential. The aluminium surfaces were analyzed with FTIR and EDX after the cleaning. It was found that almost all of the oil was eliminated in 20 min. if the oil was pure. Elimination efficiency was highly dependent on operational conditions of the process. The highest efficiency was obtained when treated at 300 W with oxygen plasma mixed with 30% argon applying negative potential more than -500 V on the aluminium surfaces. However, efficiency higher that 60% cannot be obtained at any condition if the oil contained inorganic materials.

Extraction and Purification of Rapeseed Protein (유채박 단백질의 추출 및 정제에 관한 연구)

  • Lee, Jang-Soon;Kang, Dong-Sub;Kang, Yeung-Joo
    • Korean Journal of Food Science and Technology
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    • v.22 no.7
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    • pp.780-785
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    • 1990
  • In order to establish the effective extraction and purification process of rapeseed protein, the extraction solvents were compared with one another ; and the residues of glucosinolate and phytate and the extraction yield of protein, which had been extracted by 1% sodium hexa mata-phosphate(SHMP) and purified through isoelectric precipitation, acid-washing and UF concentration, were investigated. As for the condition for extraction of rapeseed proteins, the solvent of 1% SHMP(pH 8.0) turned out the most appropriate ; so far as the purification process for the elimination of glucosinolate and phytate was concerned, the acid-washing twice or the process of the acid-washing once and UF concentration was considered the most effective. The yield and content of rapeseed protein were 37.1% and 75.3% respectively in the case of the acid-washing twice, 42.1% and 72.4% respectively in the case of the acid-washing once and UF concentraction, Consequently, with the elimination effects of glucosinolate and phytate put into consideration, the process of isoelectric precipitation, acid-washing once(pH 3.5), neutralizing(pH 7.5), UF concentration and then freeze drying proved the most effective purification process.

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A Study of Los Angeles Public School Design in Identifying Community Improvement

  • Reeder, Eric D.;Park, Suh-Jun;Kim, Youngsuk
    • Architectural research
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    • v.18 no.4
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    • pp.171-178
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    • 2016
  • Architectural utility in Richard Neutra's early twentieth century modern school design was paramount in progressively shaping salience of academic institutions, in part to move beyond neoclassical traditions in style based design. The intention being to address school and community through modern architectural solutions. Expanding on Neutra's practice, the planning and design of new public schools in Los Angeles, are advocating the integration of institutional and public spaces. This research will document through qualitative analysis of institutional design within transitioning neighborhoods, a utilitarian approach that has become foundational for positive urban change. The focus of this research will reflect upon contemporary schools designed by DalyGenik Architecture, Coop Himmelblau and Michael Maltzen Architecture. Comparing with Neutra's early modernist approach, the selected case studies will address material and spatial applications having redefined functional relationships of interior space, architectural envelope and an interconnected public realm. A dynamic peripheral condition in new school design has emerged with the elimination of decorative adornment, clarifying utilitarian intentions of institutional service to and the rejuvenation of public realms and community spaces.

Detection of Abnormal Region of Skin using Gabor Filter and Density-based Spatial Clustering of Applications with Noise (가버 필터와 밀도 기반 공간 클러스터링을 이용한 피부의 이상 영역 검출)

  • Jeon, Minseong;Cheoi, Kyungjoo
    • Journal of Korea Multimedia Society
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    • v.21 no.2
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    • pp.117-129
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    • 2018
  • In this paper, we suggest a new system that detects abnormal region of skim. First, an illumination elimination algorithm which uses LAB color model is processed on input facial image to obtain robust facial image for illumination, and then gabor filter is processed to detect the reactivity of discontinuity. And last, the density-based spatial clustering of applications with noise(DBSCAN) algorithm is processed to classify areas of wrinkles, dots, and other skin diseases. This method allows the user to check the skin condition of the images taken in real life.

The Effect of Water Soluble Polymer on the Flexural Strength and Moisture Sensitivity in MDF Cement Composites (MDF 시멘트 복합재료의 휨강도와 수분민강성에 미치는 수용성 폴리머의 영향)

  • 김태현;최상흘
    • Journal of the Korean Ceramic Society
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    • v.29 no.4
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    • pp.298-304
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    • 1992
  • Flexural strength, microstructure, hydration reaction and moisture sensitivity in macro defect-free (MDF) cement, which basically prepared of high alumina cement (HAC) and hydroxypropyl methylcellulose (HPMC) and polyvinylalcohol (PVA) as water soluble polymer were investigated. Cement composites based on HAC-PVA system were improved in flexural strength than that of HAC-HPMC system especially, the strength of specimens added to 10 wt% of polyvinylalcohol was 160 MPa. These improvements of flexural strength were attributed to not only the effect of water soluble polymer in elimination of macropores (above 100 $\mu\textrm{m}$) and cement grain bridging, but the effect of unhydrate cement as an aggregate. Moisture sensitivity and flexural strength in wet condition of MDF cement composites immersed in water at 80$^{\circ}C$ for 3 days were decreased.

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Integrated Method for Knowledge Discovery in Databases

  • Hong Chung;Park, Kyoung-Oak;Chung, Hwan-Mook
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1998.06a
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    • pp.122-127
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    • 1998
  • This paper suggests an integrated method for discovering knowledge from a large database. Our approach applies an attribute-oriented concept hierarchy ascension technique to extract generalized data from actural data in databases, induction of decision trees to measure the value of information, and knowledge reduction of rough set theory to remove dispensable attributes and attribute values. The integrated algorithm first reduce the size of database for the concept generalization, reduces the number of attributes by way of elimination condition attributes which have little influence on decision attribute, and finally induces simplified decision rules removing the dispensable attribute values by analyzing the dependency relationships among the attributes.

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Tone Reproduction effect by masking method (Masking 법에 의한 Tone 재현효과)

  • 오제웅
    • Journal of the Korean Graphic Arts Communication Society
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    • v.6 no.1
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    • pp.59-66
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    • 1988
  • One of the rising problems in the field of environmental engineering is the eutrophic phenomenon which appears in the closed water basin. This study is the elimination orthophosphate by adsorption, which is indispensible nutritive element for eutrophication Ziriconium(IV) oxide hydrate-activatedcarbon complex. which has excellent adsorptivity for orthophosphate and can easily be reused after desorption process has been made and used as adsorbents. The main purpose of this study is to obtain intraparticle diffusivity which is basic data for the design of adsorption operation the experimental results were as follows. 1. Optimum condition which gave maxinum adsorption of orthophosphate was ph5 2. Equilibrium adsorption showed good consistency with Freundlich type. q=10.80C1/2.08 3. Pore diffusivity and surface diffusivity obtained the kinetic experiment of batch adsorption were respectivity 5.38 and 2.06 ($\textrm{cm}^2$/sec)

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Model Matching of Asynchronous Sequential Machines with Input Disturbance (입력 외란이 존재하는 비동기 순차 머신의 모델 매칭)

  • Yang, Jung-Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.1
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    • pp.109-116
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    • 2008
  • Model matching problem of asynchronous sequential machines is addressed in this paper. The main topic is to design a corrective controller such that the closed-loop behavior of the asynchronous sequential machine can follow a given model, i.e., their models can be "matched" in stable states. In particular, we assume that the considered asynchronous machine suffers from the presence of an input disturbance that can cause undesirable state transitions. The proposed controller can realize both model matching and elimination of the adverse effect of the input disturbance. Necessary and sufficient condition for the existence of a corrective controller that solves model matching problem is presented. Whenever controller exists, algorithms for their design are outlined and demonstrated in a case study.