• Title/Summary/Keyword: limitation

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Treatment of High Concentration Organic Wastewater with a Sequencing Batch Reactor (SBR) Process Combined with Electro-flotation as a Solids-liquid Separation Method

  • Choi, Younggyun;Park, Minjeong;Park, Mincheol;Kim, Sunghong
    • Environmental Engineering Research
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    • v.19 no.4
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    • pp.395-399
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    • 2014
  • Operation characteristics of the sequencing batch reactor (SBR) process with electro-flotation (EF) as a solid liquid separation method (EF-SBR) were investigated. EF-SBR process showed excellent solid-liquid separation performance which enabled to separate biosolids from liquid phase within 30 min and to extend cyclic reaction time. Although influent organic loading rate was increased stepwise from 5 to 15 g COD/day, food to microorganisms (F/M) ratio could be maintained about 0.3 g COD/g VSS/day in EF-SBR because biomass concentration could be easily controlled at desired level by EF. However, it was impossible to increase biomass concentration at the same level in control SBR (C-SBR) process because solid-liquid separation by gravity settling showed a limitation at higher mixed liquor suspended solids (MLSS) concentration with 60 min of settling time. Total chemical oxygen demand (TCOD) removal efficiency of EF-SBR process was not decreased although influent organic loading rate became 3 times higher than initial value. However, it was seriously deteriorated in C-SBR process after increasing the rate over 10 g COD/day, which was accounted for insufficient organic removal by relatively higher food to microorganisms (F/M) ratio as well as biosolids wash-out by a limitation of gravity sedimentation.

Semantics in Social Web: A Case of Personalized Email Marketing (소셜 웹에서의 시맨틱스: 개인화 이메일 마케팅 개발 사례)

  • Joo, Jae-Hun;Myeong, Sung-Jae
    • The Journal of the Korea Contents Association
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    • v.10 no.6
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    • pp.43-48
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    • 2010
  • Useful emails influence on consumers' purchase behavior and activate them to visit retail stores. Regular contact with consumers by e-mail has positive effects on brand loyalty. However, email marketing has a limitation. Spam now accounts for over half of all e-mail traffic. The increase of email users has resulted in the dramatic increase of spam emails during the past few years. In this paper, we proposed an ontology-based system offering personalized email services to overcome such limitation. Our method is not the ontology-driven spam filtering, but a personalized content service considering personal interests and relations among people by using FOAF and domain ontologies. Our system was successfully tested in email marketing domain.

The Liability and Limitation of Liability Regime in the Rotterdam Rules (로테르담 규칙상의 운송인의 책임)

  • Lee, Shie-Hwan
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.42
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    • pp.189-210
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    • 2009
  • The United Nations General Assembly adopted the United Nations Convention on Contracts for the International Carriage of Goods Wholly or Partly by Sea(hereinafter referred to as "The Rotterdam Rules") on 11 December 2008. Rotterdam Rules aims to create a contemporary and uniform law providing for modern door-to-door container transport including an international sea leg. but not limited to port-to port carriage of goods. The structure of the liability regime in Rotterdam Rules are globally close to that of the Hague-Visby Rule even though it differs from that of the Hague-Visby Rules in some significant aspects. The Rotterdam Rules are very long. Therefore the Rotterdam Rules will be difficult to understand for even the skilled ship operator or owner or charterer or shipper or consignee or receiver because they are so complicated. This paper only seeks to highlight the salient features of the liability and limitation of liability regime under the Rotterdam Rules. It is expected that the harmonization and modernization of the international legal regime. coupled with the bold attempt to balance the carrier and cargo interests should lead to an overall reduction in transaction costs. increased predictability and greater commercial confidence for international business transactions.

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The Use of Local Outlier Factor(LOF) for Improving Performance of Independent Component Analysis(ICA) based Statistical Process Control(SPC) (LOF를 이용한 ICA 기반 통계적 공정관리의 성능 개선 방법론)

  • Lee, Jae-Shin;Kang, Bok-Young;Kang, Suk-Ho
    • Journal of the Korean Operations Research and Management Science Society
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    • v.36 no.1
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    • pp.39-55
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    • 2011
  • Process monitoring has been emphasized for the monitoring of complex system such as chemical processing industries to achieve the efficiency enhancement, quality management, safety improvement. Recently, ICA (Independent Component Analysis) based MSPC (Multivariate Statistical Process Control) was widely used in process monitoring approaches. Moreover, DICA (Dynamic ICA) has been introduced to consider the system dynamics. However, the existing approaches show the limitation that their performances are strongly dependent on the statistical distributions of control variables. To improve the limitation, we propose a novel approach for process monitoring by integrating DICA and LOF (Local Outlier Factor). In this paper, we aim to improve the fault detection rate with the proposed method. LOF detects local outliers by using density of surrounding space so that its performance is regardless of data distribution. Therefore, the proposed method not only can consider the system dynamics but can also assure robust performance regardless of the statistical distributions of control variables. Comparison experiments were conducted on the widely used benchmark dataset, Tennessee Eastman process (TE process), and showed the improved performance than existing approaches.

A Study on the Regulative Principle of Law in Respect to Police Function in Internationalized Age - Centering on Limitation to Police Authority Exercise - (국제화 시대의 경찰작용 통제법리에 관한 연구 -경찰권발동의 한계를 중심으로-)

  • Oh Tae-Kon;Kim Dong-Bok
    • The Journal of the Korea Contents Association
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    • v.5 no.3
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    • pp.63-71
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    • 2005
  • The police have a responsibility to exercise the police authority in the sphere of peril prevention. Such right may be decided at their discretion. So, as a management according to the police's discretion is based on order and compulsion, it can not help infringing the rights of the people. Therefore, the exercise of the police authority has to be accompanied by a legal management policy according to the principle of legal reservation based on the principle of constitutionalism. This study is to find proper directions of the police function through preparing reasonable plans to guarantee freedom and rights of the people at its maximum while maintaining the public peace and order.

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Combination of Research Methods for Factor Analysis (결합적 요인분석 연구방법)

  • Oh, Sang-Young;Hong, Hyun-Gi
    • The Journal of the Korea Contents Association
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    • v.7 no.10
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    • pp.202-210
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    • 2007
  • Factor analysis, an important research method, has been conducted as a pre-analysis of empirical researches. Sometimes, the researchers expect more information than factor analysis' limitation as well. Therefore, I suggest a method to overcome this problem. This study presents a combined research method which allow to solve the limitation of the factor analysis in social science. The combined research method consist of factor analysis, AHP(analytic hierarchy process) analysis, diffusion theory and system dynamics, which is able to explain causalities.

A Study on Application of Green Media for Low-Carbon (탄소저감형 도시계획을 위한 그린미디어(Green Media) 적용에 관한 연구)

  • Lee, Tae-Hee;Hong, Min-Ki;Oh, Deog-Seong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.6
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    • pp.2763-2772
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    • 2012
  • This study drew the reason of the limitation in low-carbon city plan from a absence of 'social sustainability' and supplemented its limitation by suggesting the new concept of city facility called Green Media. It clarified the concept of Green Media, and analyzed its effect on low-carbon city plan based on the analysis of related cases inside and outside the country. This study made an important step forward in introducing the new concept to complement social sustainability, analyzing its effect, and suggesting the applicable details.

Quality Attribute Classification of Service Elements in Business Incubation Center (창업보육센터의 주요 서비스 요소에 대한 품질속성 분류)

  • Kim, Soung-Hyun;Jeon, Young-Rok
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.37 no.3
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    • pp.75-81
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    • 2014
  • To establish a new creative economy, the worldwide efforts have been made to wriggle out the old economic paradigm after the financial crisis of 2008. When it comes to the limitation of the viability. the start up companies have a high risk of failure. Therefore business incubator (BI) should carry out the role to improve their viability. As for the maximization of the effect on the business incubating services as move in companies, it is important for BI to increase the level of business incubating services by the systemic and scientific measurement. This study showed that the quality of the BI center services was measured by Kano analysis and the previous research as follows. First, BI quality attribute by Timko's customer satisfaction came out into the attractive qualities on the 14 items that amount to the 70% of 20 business incubating services items. It is desirable to perform the strategy for the satisfaction. Secondly, basic business incubating services were interpreted as the one-dimensional quality like incubating spaces, parking facilities, security facilities, industry technology development funds, and incubating managers. Finally, training and educational service was recognized as indifferent quality. Futhermore, the improvement and the limitation of this study as well as the interpretation of analysis results are also provided.

A Field Artillery Targeting Problem with Time Window by Genetic Algorithm (유전자 알고리즘을 이용한 시간제약 포병 표적처리문제)

  • Seo, Jae-Uk;Kim, Ki-Tae;Jeong, Geon-Wook
    • Journal of the military operations research society of Korea
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    • v.36 no.2
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    • pp.11-24
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    • 2010
  • Quick precision-strike capability of the artillery will be an important factor in modern and future war and it's represented by NCW and EBO. This study is based on artillery which has time limitation of firing, such as artillery which hides when not firing, and modeling various situations to decide firing order and who to shoot. The main purpose of this study is to suggest a mathematical programming model and a genetic algorithm which satisfies the limitation of firing time. The objective function is to minimize the total firing time to spend. The results of the suggested algorithm quickly gives a best solution for a large scale field artillery targeting problems.

CLINICAL STUDY OF ARTHROCENTESIS-CASES OF CLOSED LOCK (CLOSED LOCK증례에 대한 악관절 세정술의 임상적 연구)

  • Hyun, Young-Ok;Kang, Chang-Hee;Noh, Yang-Ho;Chun, Young-Doo;Lee, Hee-Won
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.23 no.1
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    • pp.70-76
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    • 2001
  • Purpose : To evaluate the efficacy of arthrocentesis for treatment of closed lock. Material : 42 patients were diagnosed to closed lock by physical, radiographic examriation and undergone arthrocentesis. All patients have a pain and mouth opening limitation on affected site. Method : Arthrocentesis was done under conscious sedation and local infiltration anesthesia, normal saline and some steroid was injected on upper compartment of tempormandibular joint. After pumping and lavage, manual reduction procedure of anterially displaced disc was done. All the patients wear an anterior repositioning splint just after arthrocentesis. The result of arthrocentesis was assessed by pain and difference of mouth opening. Result : Difference of mouth opening after arthrocentesis was improved to 18.85mm and pain was gradually decreased. All patients were worn stabilization type splint after mean 1.84 months. 6 patients had relapse of mouth opening limitation so done arthrocentesis again and delivered good results.

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