• Title/Summary/Keyword: Complex System

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Modeling and Intelligent Control for Activated Sludge Process (활성슬러지 공정을 위한 모델링과 지능제어의 적용)

  • Cheon, Seong-pyo;Kim, Bongchul;Kim, Sungshin;Kim, Chang-Won;Kim, Sanghyun;Woo, Hae-Jin
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.10
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    • pp.1905-1919
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    • 2000
  • The main motivation of this research is to develop an intelligent control strategy for Activated Sludge Process (ASP). ASP is a complex and nonlinear dynamic system because of the characteristic of wastewater, the change in influent flow rate, weather conditions, and etc. The mathematical model of ASP also includes uncertainties which are ignored or not considered by process engineer or controller designer. The ASP is generally controlled by a PID controller that consists of fixed proportional, integral, and derivative gain values. The PID gains are adjusted by the expert who has much experience in the ASP. The ASP model based on $Matlab^{(R)}5.3/Simulink^{(R)}3.0$ is developed in this paper. The performance of the model is tested by IWA(International Water Association) and COST(European Cooperation in the field of Scientific and Technical Research) data that include steady-state results during 14 days. The advantage of the developed model is that the user can easily modify or change the controller by the help of the graphical user interface. The ASP model as a typical nonlinear system can be used to simulate and test the proposed controller for an educational purpose. Various control methods are applied to the ASP model and the control results are compared to apply the proposed intelligent control strategy to a real ASP. Three control methods are designed and tested: conventional PID controller, fuzzy logic control approach to modify setpoints, and fuzzy-PID control method. The proposed setpoints changer based on the fuzzy logic shows a better performance and robustness under disturbances. The objective function can be defined and included in the proposed control strategy to improve the effluent water quality and to reduce the operating cost in a real ASP.

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A Study on Home Economist Education with Refrence to the Business Activities in Korea (가정학교육과 취업방안연구)

  • 한상순
    • Journal of the Korean Home Economics Association
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    • v.27 no.2
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    • pp.163-185
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    • 1989
  • Korean home economics education has around 100 years history. The main aims of home economics education up 1950 had not been changed, they were mainly for the improvement of household-skill to raise both standard of living and life quality as well as womanhood. After 1960's the standard of living drastically improved and the industrialization of Korean society was quite rapidly proceeded from simple to complex one. Because of these changes, I considered that the aims and the contents of home economics education should be reexamined and reshaped. This study motivated me that especially home economics major should be trained to be competent enough to work in industrialized society as much as the input to her college education. As industialization was made progress, family member's diverse role differentiation also occurred from past simple role such as house wife or girl's high school teacher among by home economics major. In this current societal change, most of the home economics major have wish to have opportunities obtaining new kinds of employment rather than obtaining merely teaching work. With this in mind I made a study on college level home economics education of the new adjustment to current and future industrialized Korean society. (1) The full number of officially admissible home economics major in 169 Korean colleges, 70 junior colleges, and one open university were as follows, 7139, 6080, and 230 respectively. The percentages of employed of employed numbers of them for the college and junior college graduates were 26.5 and 39.0 respectively. (2) The certificate qualifications issued to college home economics major are nutritionist (1st grade and 2nd grade), clothes and textilist, home economics teacher (2nd grade for high school) and kindergartener (2nd grade), The qualifications are certified after majoring each field from major departments of college of home economics by Ministrys of Labour and Education of the Korean government. The percentages of their employment are low as mentioned earlier. (3) To find out new employment opportunity for home economics graduates in home economist in business (henceforce/HEIB) status quo of consumer division for mational enterprise was surveyed. According to govermment decree of general law of consumer protection (1980), enterprise should organize bureau (offics, subdivision) on liability to consumer's complaint. Of 89.6% of the enterprise established th subdivision in which 96.2% of employee was male (3.8% was female). Of the employee college graduate and high school graduate were 93.2% and 6.8% respectively. On the employee's major acadmic backgroud (%), economics and business administration, engineering and low-political science were 39.5, 26.2 and 11.2 respectively. (4) To study on the relation between home economics and home economist in business, the aspect of historical development of HEIB, group of HEIB employing enterprise and their nature of business were tried to find out as well as perception and evaluation by enterprise on HEIB. (a) In the united States of America employed home economics major to enterprise was organized autonomously HEIB subdivision within American Home Economics Association since 1920's and the membership of HEIB was 3,000 of the AHEA membership 50,000. (b) In Japan the Japanese founder HEIB had three times the bilateral congress with the U.S.HEIB and had 10th anniversary celebration in 1988. Japanese HEIB member are not necessary to be home economics graduates but should have certificate as consumer adviser effected by the Minister of Trade and Industry. Japanese subdivision of consumer affaire within Japanese enterprise employ the consumer adviser with the certificate. Because of this different system from the United Sates, Japanese HEIB call their title "HEEB" instead of HEIB. The Japanese consumer adviser certificate system had initiated since 1980 and it belongs to 2nd level national qualification certificate. Currently active membership of Japanese "HEEB" association had increased from 115 (in 1979) to 319 in 1988. (5) For the opening of the future new employment of home economics graduates to enterprise and qualification required for the HEIB by national enterprise in Korea, I studied on the courses which seem to be important and required by employee in the field of HEEB in the United States of America and preliminary curriculum for home economics related major student aimning to be the future "HEEB" by Japanese HEEB study group of Japanese Association of Home Economics. It is suggested that it is very important and urgent to realize as home economics educator to have common deep concern and endeavors on opening new employment for our home economics major student1), we should try to publicize strongly and let enterprise and consumer protection board realize that employee in the subdivision of consumer protection should be the one who well experienced home economics major graduates2), we, home economics educator, should try to develop actively new curriculum in line of the suggestion made earlier for our future home economics major student of open broadly their future employment opportunities3), we, home economics educators, should try to have consensus on whether we should have support from government in terms of receiving national qualification certificate on consumer pretection or not4), and I would appreciate if the Korean Home Economics Association and Korean Home Management Society paydeep and positive concern on this matter.

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Functional Magnetizing Treatment of Natural Quartz and Volcanic Lava Scoria (내추럴 퀄쯔와 화산암재 스코리아의 기능성 마그네타이징 처리)

  • 소대화;소현준;배두안;김정희
    • Journal of the Speleological Society of Korea
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    • no.63
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    • pp.1-8
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    • 2004
  • The non-magnetic materials with non-conductive showing high structure dispersity were developed on the base of natural quartz and lava-scoria which was collected from Je-ju island in Korea, and treated by methane-chemical technology those were obtained novel properties of magnetization through the analyzing. Depending on the processing conditions and subsequent applications the materials produced by strong methane-chemical reaction (MCR) in alcohol solution showed concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segnetomagnetics, containing a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds were synthesized having thickness up to 10~50 nm and showing magnetic, electrical and other properties. It was confirmed in magnetizing process that powders of quartz and lava-scoria produced by MCR were better oil adsorbent as of oleophilic and floating matter on water surface although their specific gravities are comparably more than 1 in quartz or less than unity, as that of water, in lava-scoira. Therefore, it will be Possible and very useful to remove low density and light gravity oil spillage in difficult recovery from sea and inland water contamination spread on water surface, by marine accident and ship sinking accident occurring frequently in recent years, by way of magnetic adsorbent conveyer system in continuous, if it could be built up the mass Production system of water-floating magnetizable oleophilic adsorbent materials with use of iow cost and good Qualify lava-scoria spread on volcano district in Je-ju island. And, there will also be urgent advent of necessity with strong possibility to develop useful applications of various magnetic functional materials include oleophilic adsorbent for removal of sea oil-contaminants and maritime pollutants, and other kinds of various utilities in industrial applications and practical uses of novel functional materials in the fields of environments and health care applications with in deep expectation.

f-MRI with Three-Dimensional Visual Stimulation (삼차원 시각 자극을 이용한 f-MRI 연구)

  • Kim C.Y.;Park H.J.;Oh S.J.;Ahn C.B.
    • Investigative Magnetic Resonance Imaging
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    • v.9 no.1
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    • pp.24-29
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    • 2005
  • Purpose : Instead of conventional two-dimensional (2-D) visual stimuli, three-dimensional (3-D) visual stimuli with stereoscopic vision were employed for the study of functional Magnetic Resonance Imaging (f-MRI). In this paper f-MRI with 3-D visual stimuli is investigated in comparison with f-MRI with 2-D visual stimuli. Materials and Methods : The anaglyph which generates stereoscopic vision by viewing color coded images with red-blue glasses is used for 3-D visual stimuli. Two-dimensional visual stimuli are also used for comparison. For healthy volunteers, f-MRI experiments were performed with 2-D and 3-D visual stimuli at 3.0 Tesla MRI system. Results : Occipital lobes were activated by the 3-D visual stimuli similarly as in the f-MRI with the conventional 2-D visual stimuli. The activated regions by the 3-D visual stimuli were, however, larger than those by the 2-D visual stimuli by $18\%$. Conclusion : Stereoscopic vision is the basis of the three-dimensional human perception. In this paper 3-D visual stimuli were applied using the anaglyph. Functional MRI was performed with 2-D and 3-D visual stimuli at 3.0 Tesla whole body MRI system. The occipital lobes activated by the 3-D visual stimuli appeared larger than those by the 2-D visual stimuli by about $18\%$. This is due to the more complex character of the 3-D human vision compared to 2-D vision. The f-MRI with 3-D visual stimuli may be useful in various fields using 3-D human vision such as virtual reality, 3-D display, and 3-D multimedia contents.

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The Stock Portfolio Recommendation System based on the Correlation between the Stock Message Boards and the Stock Market (인터넷 주식 토론방 게시물과 주식시장의 상관관계 분석을 통한 투자 종목 선정 시스템)

  • Lee, Yun-Jung;Kim, Gun-Woo;Woo, Gyun
    • KIPS Transactions on Software and Data Engineering
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    • v.3 no.10
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    • pp.441-450
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    • 2014
  • The stock market is constantly changing and sometimes the stock prices unaccountably plummet or surge. So, the stock market is recognized as a complex system and the change on the stock prices is unpredictable. Recently, many researchers try to understand the stock market as the network among individual stocks and to find a clue about the change of the stock prices from big data being created in real time from Internet. We focus on the correlation between the stock prices and the human interactions in Internet especially in the stock message boards. To uncover this correlation, we collected and investigated the articles concerning with 57 target companies, members of KOSPI200. From the analysis result, we found that there is no significant correlation between the stock prices and the article volume, but the strength of correlation between the article volume and the stock prices is relevant to the stock return. We propose a new method for recommending stock portfolio base on the result of our analysis. According to the simulated investment test using the article data from the stock message boards in 'Daum' portal site, the returns of our portfolio is about 1.55% per month, which is about 0.72% and 1.21% higher than that of the Markowitz's efficient portfolio and that of the KOSPI average respectively. Also, the case using the data from 'Naver' portal site, the stock returns of our proposed portfolio is about 0.90%, which is 0.35%, 0.40%, and 0.58% higher than those of our previous portfolio, Markowitz's efficient portfolio, and KOSPI average respectively. This study presents that collective human behavior on Internet stock message board can be much helpful to understand the stock market and the correlation between the stock price and the collective human behavior can be used to invest in stocks.

Land Cover Classification of Coastal Area by SAM from Airborne Hyperspectral Images (항공 초분광 영상으로부터 연안지역의 SAM 토지피복분류)

  • LEE, Jin-Duk;BANG, Kon-Joon;KIM, Hyun-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.21 no.1
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    • pp.35-45
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    • 2018
  • Image data collected by an airborne hyperspectral camera system have a great usability in coastal line mapping, detection of facilities composed of specific materials, detailed land use analysis, change monitoring and so forh in a complex coastal area because the system provides almost complete spectral and spatial information for each image pixel of tens to hundreds of spectral bands. A few approaches after classifying by a few approaches based on SAM(Spectral Angle Mapper) supervised classification were applied for extracting optimal land cover information from hyperspectral images acquired by CASI-1500 airborne hyperspectral camera on the object of a coastal area which includes both land and sea water areas. We applied three different approaches, that is to say firstly the classification approach of combined land and sea areas, secondly the reclassification approach after decompostion of land and sea areas from classification result of combined land and sea areas, and thirdly the land area-only classification approach using atmospheric correction images and compared classification results and accuracies. Land cover classification was conducted respectively by selecting not only four band images with the same wavelength range as IKONOS, QuickBird, KOMPSAT and GeoEye satelllite images but also eight band images with the same wavelength range as WorldView-2 from 48 band hyperspectral images and then compared with the classification result conducted with all of 48 band images. As a result, the reclassification approach after decompostion of land and sea areas from classification result of combined land and sea areas is more effective than classification approach of combined land and sea areas. It is showed the bigger the number of bands, the higher accuracy and reliability in the reclassification approach referred above. The results of higher spectral resolution showed asphalt or concrete roads was able to be classified more accurately.

The Evaluation of Meteorological Inputs retrieved from MODIS for Estimation of Gross Primary Productivity in the US Corn Belt Region (MODIS 위성 영상 기반의 일차생산성 알고리즘 입력 기상 자료의 신뢰도 평가: 미국 Corn Belt 지역을 중심으로)

  • Lee, Ji-Hye;Kang, Sin-Kyu;Jang, Keun-Chang;Ko, Jong-Han;Hong, Suk-Young
    • Korean Journal of Remote Sensing
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    • v.27 no.4
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    • pp.481-494
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    • 2011
  • Investigation of the $CO_2$ exchange between biosphere and atmosphere at regional, continental, and global scales can be directed to combining remote sensing with carbon cycle process to estimate vegetation productivity. NASA Earth Observing System (EOS) currently produces a regular global estimate of gross primary productivity (GPP) and annual net primary productivity (NPP) of the entire terrestrial earth surface at 1 km spatial resolution. While the MODIS GPP algorithm uses meteorological data provided by the NASA Data Assimilation Office (DAO), the sub-pixel heterogeneity or complex terrain are generally reflected due to coarse spatial resolutions of the DAO data (a resolution of $1{\circ}\;{\times}\;1.25{\circ}$). In this study, we estimated inputs retrieved from MODIS products of the AQUA and TERRA satellites with 5 km spatial resolution for the purpose of finer GPP and/or NPP determinations. The derivatives included temperature, VPD, and solar radiation. Seven AmeriFlux data located in the Corn Belt region were obtained to use for evaluation of the input data from MODIS. MODIS-derived air temperature values showed a good agreement with ground-based observations. The mean error (ME) and coefficient of correlation (R) ranged from $-0.9^{\circ}C$ to $+5.2^{\circ}C$ and from 0.83 to 0.98, respectively. VPD somewhat coarsely agreed with tower observations (ME = -183.8 Pa ~ +382.1 Pa; R = 0.51 ~ 0.92). While MODIS-derived shortwave radiation showed a good correlation with observations, it was slightly overestimated (ME = -0.4 MJ $day^{-1}$ ~ +7.9 MJ $day^{-1}$; R = 0.67 ~ 0.97). Our results indicate that the use of inputs derived MODIS atmosphere and land products can provide a useful tool for estimating crop GPP.

Survey of Unexpected Antibodies Identified at a General Hospital in Jeju (제주지역 일개 종합병원에서 동정된 비예기항체의 실태조사)

  • Chong, Moosang;Lee, Kyu-taeg;Cho, Young-Kuk
    • Korean Journal of Clinical Laboratory Science
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    • v.49 no.4
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    • pp.390-394
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    • 2017
  • Unexpected antibody screening and identification tests are highly important in the prevention of hemolytic transfusion reactions. Therefore, it is highly recommended to perform unexpected antibody screening test in all transfusion candidates. Here, the frequency and distribution of unexpected antibodies identified in Jeju for the past 3 years were evaluated. Between Jan 2014 and Dec 2016, unexpected antibody screening test was performed for 10,360 sera of transfusion candidates in Jeju general hospital using a column agglutination method with the Ortho BioVue system (Ortho-clinical Diagnostics, Raritan, NJ, USA). Eighty-seven (0.84%) of 10,360 cases that underwent unexpected antibiotics screening showed positive results. Among them, unexpected antibodies were identified in 41 cases (0.40%). Unidentified antibodies were detected in 8 cases (19.51%) and autoantibodies were detected in 3 cases (7.32%). The anti-E antibody included in warm antibodies were detected most frequently in 8 cases (19.51%); 6 cases (14.63%) of anti-E + anti-c antibody and 3 cases (7.32%) of $anti-Le^a+anti-Le^b$. $Anti-Le^a$ and $anti-Le^b$ antibodies were detected in 2 cases (4.88%), respectively. The anti-D, $anti-Di^a$, $anti-Fy^b$, $anti-Jk^a$, $anti-Jk^b$, anti-M and anti-P1 were detected in 1 case (2.44%). Complex antibodies were detected in 1 case (2.44%) in anti-C+anti-D and anti-E+anti-c+$anti-Jk^b$, respectively. In this study, we analyzed the frequency and distribution of unexpected antibodies in one general hospital for the past 3 years. However, there has been a general increase in multicultural families and foreign workers in Jeju, and it would be a meaningful study to compare the frequency and distribution of unexpected antibodies.

Ammonia Volatilization from Coated Urea in Paddy Soil of Direct Seeding Rice Culture (벼 건답직파재배에서 피복요소 시용에 따른 암모니아 휘산)

  • Lee, Dong-Wook;Park, Ki-Do;Park, Chang-Young;Jeon, Weon-Tae;Son, Il-Soo;Park, Sung-Tae;Lee, Suk-Soon;Kang, Ui-Gum
    • Korean Journal of Soil Science and Fertilizer
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    • v.38 no.6
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    • pp.328-333
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    • 2005
  • Ammonia volatilization is the major form of nitrogen (N) loss from flooded paddy soils and causes low N use efficiency. The effects of controlled release fertilizer (latex coated urea complex fertilizer, LCU) on reducing N loss by ammonia volatilization was measured comparing with urea in rice culture system of direct seeding on dry soil. In the treatment of urea, $NH_4-N$ concentration in surface water after flooding increased rapidly up to $8-10mg\;L^{-1}$ as affected by topdressing, while in the LCU treatment $NH_4-N$ concentration in surface water was less than $1mg\;L^{-1}$ during rice growing season. Relation of $NH_4-N$ concentration in surface water and ammonia volatilization was significant in urea treatment. The amount of ammonia volatilized from rice paddy of LCU treatment was $2.4-3.0kg\;ha^{-1}$ and the rate of ammonia volatilization from N fertilizer applied was only 2.0-2.3% compared with 5.9-7.9% in urea treatment. Therefore, N loss by ammonia volatilization could be reduced by 72-76% with by LCU compared with urea in rice culture system of direct seeding on dry soil.

Au-Ag-Te Mineralization by Boiling and Dilution of Meteoric Ground-water in the Tongyeong Epithermal sold System, Korea: Implications from Reaction Path Modeling (광화유체의 비등과 희석에 의한 통영 천열수계 Au-Ag-Te 장화작용에 대한 반응경로 모델링)

  • Maeng-Eon Park;Kyu-Youl Sung
    • Economic and Environmental Geology
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    • v.34 no.6
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    • pp.507-522
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    • 2001
  • At the Tongyeong mine, quartz, rhodochrosite (kutnahorite), muscovite, illite, pyrite, galena, chalcopyrite. sphalerite, acanthite, and hessite are the principal vein minerals. They were deposited under epithermal conditions in two stages. Ore mineral assemblages and associated gangue phases in stage can be clearly divided into two general associations: an early cycle (band) that appeared with introduction of most of the sulfides and electrum, and a later cycle in which base metal and carbonate-bearing assemblages (mostly rhodochrosite) became dominant. Tellurides and some electrum occur as small rounded grains within subhedral-to euhedral pyrite or anhedral galena in stageII. Sulfide mineralization is zoned from pyrite to galena and sphalerite. We have used computer modeling to simulate formation of four stages of vein genesis. The reaction of a single fluid with andesite host rock at 28$0^{\circ}C$, isobaric cooling of a single fluid from 26$0^{\circ}C$ to 12$0^{\circ}C$, and boiling and mixing of a fluid with both decreasing pressure and temperature were studied using the CHILLER program. Calculations show that the precipitation of alteration minerals is due to fluid-andesite interaction as temperature drops. Speciation calculations confirm that the hydrothermal fluids with moderately high salinities and pH 5.7 (acid), were capable of transporting significant quantities of base metals. The abundance of gold in fluid depends critically on the ratio of total base metals and iron to sulfide in the aqueous phase because gold is transported as an Au(HS)$_2$- complex, which is sensitive to sulfide activity. Modeling results for Tongyeong mineralization show strong influence of shallow hydrogenic processes such as boiling and fluid mixing. The variable handing in stageII mineralization is best explained by maltiple boilings of hydrothermal fluid followed by lateral mixing of the fluid with overlying diluted, steam-heated ground water. The degree of similarity of calculated mineral assemblages and observed electrum composition and field relationships shows the utility of the numerical simulation method in identifying chemical processes that accompany boiling and mixing in Te-bearing Au-Ag system. This has been applied in models to narrow the search area for epithermal ores.

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