• Title/Summary/Keyword: MAL

Search Result 899, Processing Time 0.027 seconds

Diagnosis of power supply by analysis of chaotic nonlinear dynamics (카오스 비선형 동력학 해석에 의한 수·변전설비의 진단)

  • Bae, Young-Chul
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.8 no.1
    • /
    • pp.113-119
    • /
    • 2013
  • In this paper, n order to degrade of diagnosis of power supply by using Poincare map and fractal dimension with temperature measured by infrared camera. we review the characteristic of temperature variation according to pattern variation of power supply in chemical industry complex. As a simulation results we can be realized the characteristic behaviors of nonlinear dynamics in the poincare mal and fractal dimension. In the future verification method requires through additional research.

Design of 6-DOF Attitude Controller of the UAV Simulator's Hovering Model

  • Keh, Joong-Eup;Lee, Mal-Young;Kim, Byeong-Il;Chang, Yu-Shin;Lee, Man-Hyung
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.969-974
    • /
    • 2004
  • For a maneuvering unmanned autonomous helicopter, it is necessary to design a proper controller of each flight mode. In this paper, overall helicopter dynamics is derived and hovering model is linearized and transformed into a state equation form. However, since it is difficult to obtain parameters of stability derivatives in the state equation directly, a linear control model is derived by time-domain parametric system identification method with real flight data of the model helicopter. Then, two different controllers - a linear feedback controller with proportional gains and a robust controller - are designed and their performance is compared. Both proposed controllers show outstanding results by computer simulation. These validated controllers can be used to autonomous flight controller of a real unmanned model helicopter.

  • PDF

Development of IoT-based non-cleaning water quality measuring equipment

  • Kim, Heung Soe;Ko, Woori;Ko, Kyoung Hak
    • Agribusiness and Information Management
    • /
    • v.9 no.1
    • /
    • pp.18-22
    • /
    • 2017
  • It takes lots of time and labor if a worker have to measure the water quality at a certain but designated time every day in an un-automated aqua farm. In addition, if the equipment is soaked in the sea water consistently, it will be contaminated by diverse floating matters and barnacles, and it often becomes mal-functional within 2~3 months. Therefore, we need to develop a system with which the sensed data could be checked in real time and operated automatically, while preventing the contamination of the sensor, a crucial component for water quality measuring equipment, as much as possible, and increasing the replacement cycle. We have developed a non-cleaning water quality measuring equipment and its software which are used in the fishery household of offshore aqua farms. By providing the workers with a mobile application which has a function of monitoring the water quality in real time, they can check the situation directly without going to the fishery household.

The Effect of Non-uniform Superheat on the Performance of a Multi-path Evaporator (다중 유로에서 과열도의 불균형에 따른 증발기의 성능 특성에 관한 연구)

  • 최종민;김용찬
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.15 no.12
    • /
    • pp.1043-1048
    • /
    • 2003
  • An experimental investigation was executed to determine the capacity degradation due to non-uniform refrigerant distribution in a multi-path evaporator. In addition, the possibility of recovering the capacity reduction by controlling the refrigerant distribution among refrigerant paths was assessed. The finned-tube evaporator, which had a three-path and three-depth-row, was tested by controlling inlet quality, exit pressure, and exit superheat for each refrigerant path. The capacity reduction due to superheat unbalance between each path was as much as 30%, even when the overall evaporator superheat was kept at a target value of 5.6$^{\circ}C$. It may indicate that the internal heat transfer within the evaporator assembly caused the partial capacity drop. For the evaporator having air mal-distributions, the maximum capacity reduction was found to be 8.7%. A 4.5% capacity recovery was obtained by controlling refrigerant distribution to obtain the target superheat at the outlet of each path.

INFORMATION SEARCH BASED ON CONCEPT GRAPH IN WEB

  • Lee, Mal-Rey;Kim, Sang-Geun
    • Journal of applied mathematics & informatics
    • /
    • v.10 no.1_2
    • /
    • pp.333-351
    • /
    • 2002
  • This paper introduces a search method based on conceptual graph. A hyperlink information is essential to construct conceptual graph in web. The information is very useful as it provides summary and further linkage to construct conceptual graph that has been provided by human. It also has a property which shows review, relation, hierarchy, generality, and visibility. Using this property, we extracted the keywords of web documents and made up of the conceptual graph among the keywords sampled from web pages. This paper extracts the keywords of web pages using anchor text one out of hyperlink information and makes hyperlink of web pages abstract as the link relation between keywords of each web page. 1 suggest this useful search method providing querying word extension or domain knowledge by conceptual graph of keywords. Domain knowledge was conceptualized knowledged as the conceptual graph. Then it is not listing web documents which is the defect of previous search system. And it gives the index of concept associating with querying word.

Fundamental Studies on the Migrating Course of Fish Around the Set Net - Enviremental Conditions of fishing Ground - (정치망어장의 어도 형성에 관한 기초연구 ( 1 ) - 어장환경 요인 -)

  • Lee, Ju-Hee;Lee, Byoung-Gee;Youm, Mal-Gu
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.22 no.3
    • /
    • pp.1-7
    • /
    • 1986
  • This is a basic study of further investigating the effect of oceanographic conditons, such as bottom profile, currents, and temperature, to the fish migrating course around the set-net. The survey was held at Dojang Po, southern part of Geoje Island, from July to October in 1985. There was a sea valley of which depth was 20 to 40 meters around the set-net. Near the bottom of that sea valley, there was different current pattern to the upper layer. In the sea calm condition of July and October, the vertical profiles of current and water temperature were simple. But in rough condition of September, they were complicated because of wind tuburance.

  • PDF

Pasting Properties of Crude ${\beta}-Glucan$ from Spent Brewer's Yeast on Wheat Flour and Starch

  • Yoo, Moon-Sik;Lee, Young-Tack
    • Food Science and Biotechnology
    • /
    • v.16 no.3
    • /
    • pp.485-488
    • /
    • 2007
  • Plentiful amount of spent yeast has been produced as a by-product from breweries. ${\beta}-Glucan$ was prepared from the spent brewer's yeast in a crude form with hot water extraction and subsequent enzymatic treatment. The crude ${\beta}-glucan$ preparation consisted of mainly glucan (53% of total wt), containing approximately 35% ${\beta}-glucan$ content of total weight. The effects of crude ${\beta}-glucan$ substitution (1-9%) on pasting properties of wheat flour and starch were determined using a Rapid Visco-Analyzer (RVA). Incorporation of yeast ${\beta}-glucan$ into wheat flour and starch significantly decreased peak and [mal viscosities, but slightly increased setback viscosity. The setback viscosity was considerably higher in starch/${\beta}-glucan$ suspension than in flour/${\beta}-glucan$ suspension. It was suggested that preparation of yeast ${\beta}-glucan$ into aqueous dispersion might affect pasting behaviors of wheat flour and starch.

On Negative Imperatives in Korean

  • Han, Chung-hye;Lee, Chung-min
    • Proceedings of the Korean Society for Language and Information Conference
    • /
    • 2002.02a
    • /
    • pp.59-68
    • /
    • 2002
  • In this paper, we address two questions concerning negative imperatives in Korean: (i) what is the morpho-syntactic nature of mal in negative imperatives\ulcorner; and (ii) why is it impossible to form negative imperatives with short negation an\ulcorner We will argue that the clause structure of imperatives include a projection of deontic modality and a projection of imperative operator encoding illocutionary force, and that oaf is a lexicalization of long negation and deontic modality. We then propose that a negative imperative with short negation is ruled out because such construction maps onto incoherent interpretation which can be spelled out as I direct you to bring about a negative state or a negative event.

  • PDF

A Review on World Geothermal Assessment (전세계 지열부존량 평가에 대한 개관)

  • Song, Yoon-Ho;Lee, Young-Min;Lee, Tae-Jong
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2008.05a
    • /
    • pp.613-616
    • /
    • 2008
  • Assessment of geothermal resources like other earth resources is a starting point for decision makers or stakeholders to set up basic plan on its development and R&D policies. In this context, there have been various works on world geothermal assessment, to report different estimates from each other. In this paper, we first introduce the definition of geothermal potential mainly adopted from the article by Muffler and Cataldi (1978) and then summarize the estimates made so far referring the work by Bertani (2003). An updated estimates by Stefansson (2005) are also reviewed in terms of identified resources separately for high-temperature resources for power generation and low-temperature ones for direct-use. Recent estimate of US geothermal resources by MIT (2006) using a volumetric method with extensively accumulated data base is discussed. Finally, we introduce the first geothermal assessment in Korea recently made and discuss its importance.

  • PDF