• Title/Summary/Keyword: Process adjustment

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Synthesis of Cubic and Rod Shapes CaCO3 by Hydrothermal Method (수열합성법을 이용한 큐빅과 로드형의 탄산칼슘 합성)

  • Kang, Kuk-Hyoun;Jeon, Sang-Chul;Hyun, Mi-Ho;Lee, Dong-Kyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.6
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    • pp.255-261
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    • 2016
  • $CaCO_3$ was applied in various industries including rubber, plastics, paint, paper, food additives, and acid neutralizer, etc., owing to its excellent physical and chemical characteristics as well as various appearances of crystals and many reserves. In particular, research on controlling the structure and shape of $CaCO_3$ has attracted considerable attention recently, because the whiteness and physical characteristics of $CaCO_3$ depend on the size and shapes of the particles. In this study, $CaCO_3$ was synthesized using $CaCl_2$ and $(NH4)_2CO_3$, which has multi-shapes and structures, using a self-assembly method with a hydrothermal method. The structure and morphology of the $CaCO_3$ could be controlled by adjusting the pH and precursor concentration. In particular, the pH adjustment appeared to be a critical factor for the morphology and crystal form. In addition, the calcite and cubic shape were obtained at pH 7, while the mixed calcite, aragonite structure, and rod shapes appeared at pH 7 and over. Through an analysis of the particle formation process, the formation of the calcium carbonate particles was confirmed. The physicochemical properties of the synthesized $CaCO_3$ were analyzed by SEM, XRD, EDS, FTIR, and TG/DTA.

Numerical Study on the Supply and Exhaust Port Size and Fire Management Method in the Semi-transverse Ventilation System for Road Tunnel (도로터널 반횡류환기시스템에서 급배기 포트개도 및 화재시 운영방안에 관한 수치해석적 연구)

  • Ryu, Ji-Oh;Kim, Jin-Su;Rie, Dong-Ho
    • Fire Science and Engineering
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    • v.30 no.2
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    • pp.68-74
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    • 2016
  • In semi-transverse ventilation system applied for road tunnel, adjustment of the port opening ratio is an essential part for uniform airflow rate per unit length over the entire tunnel. However, it has not been considered decently throughout the design process and operating of the tunnel. Therefore, in this study, we developed a program for the calculation of the opening size ratio of supply or exhaust port in transverse ventilation system and carried out the research to present a management plan for the port. In supply duct system, the opening size of the port had a tendency to increase and then decrease later when it gradually becomes closer toward the bulkhead at the beginning of the duct the minimum opening degree is to appeared as 56%. In the exhaust system, port size is the smallest at the beginning of duct as 15%, has shown a tendency to increase towards the bulk head. As results of estimating the air flow rate for 300 m intervals, the exhaust flow rate in the center of tunnel appeared to be extremely low as 8.1% and 12.5% when port size is constant and is adjusted supply type. Thus, even if the normal ventilation efficiency is declines, yet it is highly recommend adjusting the port size in order to obtain a uniform flow rate at fire accidents.

The Effects of Visual Rhythmic Stimulation in Gait and Proprioception with Chronic Stroke Patients (시각리듬자극이 만성뇌졸중 환자의 보행과 고유수용감각에 미치는 영향)

  • Cho, Nam-Jeong;Lee, Dong-Yeop
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.9
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    • pp.3353-3357
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    • 2010
  • The purpose of this study is to investigate the effect of visual rhythmic stimulation in gait ability and proprioception in chronic stroke patients. Twenty-one persons after six months post stroke participated in pre and post test control. The subjects were randomly assigned to a rhythmic visual stimulation(RVS) group (n=10) and control group (n=11). Training process was practiced with exercise on thirty minutes a day, three days a week for four weeks. To find out the effect, inspected the proprioception test and gait characteristics by gait analysis. In gait characteristics, the walking speed, cadence and the TUG time were significantly different from RVS group. The proprioception were significantly different RVS and control group. This study showed that the RVS training increased better functional activity by postural adjustment and gait learning of chronic stroke patients than that of control group. And so, the RVS training of hemiplegic patients was very important to successive rehabilitation. A continuous examination of RVS training could be practical use of physical therapy with exercise.

A Study on the Effects of After-purchase Feedback About Customer Service Quality on Purchase Process - Focusing on Internet Shopping Mall - (고객 서비스 품질에 대한 구매 후기 댓글이 구매과정에 미치는 영향 - 인터넷 쇼핑몰을 중심으로 -)

  • Shin, Chang-Nag;Kim, Young-Ei;Park, Young-Kyun
    • Journal of Distribution Research
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    • v.14 no.1
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    • pp.27-44
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    • 2009
  • This research classified the customer service factor of on-line shopping mall into tangibility, reliability, responsiveness, and empathy and analyzed the effect that the factors affect to consumer's purchase and re-purchase. If we present suggestions on the basis of these results of study, we would provide next two points: First, purchasers have utilized online shopping mall who pursued free from hard sell that being done in off-line and convenience of purchase affected more by reliability and responsiveness such as the fame of shopping mall that visit, reliability of security, and quick product search than the Customer of After-purchase Feedback influence for online purchasers decision factor out of consumer's purchase and re-purchase by on-line shopping mall customer service factor. Second, This study analyzed that online re-purchaser recognized the Customer of After-purchase Feedback factor high and built their loyalty through friendly emotion of on-line shopping mall and satisfaction of shopping mall service, and recommendation. In addition, they behave themselves as an affirmative messenger that is role of the Customer of After-purchase Feedback that make active opinion presentation and participation through community by important adjustment impact that empathy factor of on-line shopping mall customer service.

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Development of Improved Clustering Harmony Search and its Application to Various Optimization Problems (개선 클러스터링 화음탐색법 개발 및 다양한 최적화문제에 적용)

  • Choi, Jiho;Jung, Donghwi;Kim, Joong Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.630-637
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    • 2018
  • Harmony search (HS) is a recently developed metaheuristic optimization algorithm. HS is inspired by the process of musical improvisation and repeatedly searches for the optimal solution using three operations: random selection, memory recall (or harmony memory consideration), and pitch adjustment. HS has been applied by many researchers in various fields. The increasing complexity of real-world optimization problems has created enormous challenges for the current technique, and improved techniques of optimization algorithms and HS are required. We propose an improved clustering harmony search (ICHS) that uses a clustering technique to group solutions in harmony memory based on their objective function values. The proposed ICHS performs modified harmony memory consideration in which decision variables of solutions in a high-ranked cluster have higher probability of being selected than those in a low-ranked cluster. The ICHS is demonstrated in various optimization problems, including mathematical benchmark functions and water distribution system pipe design problems. The results show that the proposed ICHS outperforms other improved versions of HS.

Chemical/Electro-Chemical Method for Swine Wastewater Treatment (화학적/전기화학적 방법을 이용한 돈사폐수 처리)

  • Yoon, S.J.;Jo, W.S.;Kim, C.H.;Park, J.I.;Shin, J.S.;Ra, C.S.
    • Journal of Animal Science and Technology
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    • v.45 no.4
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    • pp.641-648
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    • 2003
  • In a batch mode treatment process, which electrolyzes the wastewater after derivation of N-P crystal formation and recovery, the characteristics of pollutant removal induced with the changes of loading rate and hydraulic retention time were studied. $MgCl_2$ was used as Mg source for the formation of struvite and the molar ratio of $MgCl_2$ to $PO_4^{3-}$ in influent was 1.3. When analyzing the average treatment efficiencies and removal characteristics obtained from four separate operations (Run I, II, III, IV), removal efficiencies of PO43- was not function of its loading rate. Under a condition of sufficient aeration and Mg source provided, over 88% of $PO_4^{3-}$ was eliminated by the formation of MAP without any pH adjustment, in spite of loading rate variation. An optimum-loading rate of NH4-N to achieve high removal efficiency was approximately $100g/m^3/d$. Below that loading rate, the removal of NH4-N was proportional to the loading rate into the system, and hence stable and high removal efficiency, over 90%, was achieved. However, when the loading rate increased over that rate, removal efficiency began to drop and fluctuate. Removal efficiency of TOCs was dependant upon the hydraulic retention time ($r^2$=0.97), not upon the loading rate. Stable and high color removal (94%) was obtained with 2 days of HRT in electrolysis reactor.

Perforation Adjustment of Unit Package for 'Fuji' Apples during Short-term Cold Storage and Export Simulation ('후지' 사과의 단기 저온저장 및 모의수출 과정에서 소포장의 천공도 조절 효과)

  • Kim, Su-Jeong;Park, Youn-Moon;Yoon, Tae-Myung
    • Horticultural Science & Technology
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    • v.32 no.2
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    • pp.184-192
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    • 2014
  • Various types of unit packaging methods were applied for 'Fuji' apples during short-term cold storage and export simulation. Gas tightness of the package was controlled stepwise in the successive two-year experiments using different perforation treatments (none, punch hole, or pinhole) and sealing methods (tie v s. heat seal). Risk of tight packaging and effectiveness of macroperforation on weight loss and quality maintenance were analyzed as related to changes in gas concentration inside the packages. Immediately after harvest, each 5 apple units were packaged in $40{\mu}m$ polypropylene (PP) film bags, stored 4 weeks at $0^{\circ}C$, and then put on the shelf for one week at ambient temperature in the preliminary experiment, In the main experiment, export process was imposed after storage simulating 2 week refrigerated container shipment at $0^{\circ}C$ plus one week local marketing at ambient temperature. Non-perforated film packaging with relatively high gas tightness induced flesh browning caused by carbon dioxide accumulation regardless of the sealing methods. Among perforated film packaging, in contrast, atmospheric modification was partly established only in the pinhole treatment and flesh browning symptom was not observed in all the treatments. Even the punch hole perforated film packaging without gas tightness effectively reduced the weight loss, whereas had slight benefits for quality maintenance. Reduced perforation using pinhole treatment seemed to improve sensory texture, while effects on physicochemical quality were insignificant. Overall results suggest the need of more minute perforation treatments on the packaging film to ensure modified atmosphere effects on quality maintenance.

Exploratory study on the Moral Injury among Female North Korean Refugees: Qualitative Content Analysis of Qualitative Studies on Female North Korean Refugees (탈북여성들이 경험하는 도덕적 손상에 관한 탐색적 연구: 탈북여성을 대상으로 한 질적 선행연구물 내용분석)

  • Shim, Woochan;Lee, Soon Min
    • The Journal of the Korea Contents Association
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    • v.18 no.4
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    • pp.636-652
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    • 2018
  • This study is about applying the concept of moral injury in reinterpreting and understanding the experience of female North Korean refugees who have experienced psychological trauma and are struggling with adjusting in their everyday lives. The database KISS and DBpia were used to search for academic peer-reviewed articles published before August 13th in 2017, using 'female or women North Korean,' 'female or women relocated North Korean,' and 'female or women North Korean defector' as keywords. In total 51 studies were finally selected for content analysis and the result were the following. First, listing from the most often occurring study topic to the least occurring topic in order: post-defection adjustment related, mothering experience, experience of North Korean regime and Korean War, work or job or employment related, recovering from psychological trauma as well as growth and resilience related, experiences in China, trauma and psychological difficulties, anxiety treatment process and effects. Second, words related to psychological aspect of moral injury appeared 260 times in 51 selected studies, changes in the existential belief appeared 82 times, cognitive aspects of moral injury appeared 71 times, and behavioral aspects 21 times. Third, two main contexts emerged to be the antecedent that led to moral injury and they were 'identity denial' and 'dismantled family.' In attempts to find opposite cases or stories where aspects of moral injury were not found despite the existence of its antecedents and it was 'identity restructuring.' Based on the finding, practice implications that could help female North Korean refugees prevent or recover from moral injury were suggested.

Introduction of the Basin Sewerage Plan in Japan through Case Studies of the Lake Biwa Sewerage System (비와호 유역하수도 사례분석을 통한 일본 유역하수도계획의 소개)

  • Han, Mideok;Park, Bae Kyung;Park, Ji Hyoung;Kim, Yong Seok;Rhew, Doug Hee
    • Journal of Korean Society of Environmental Engineers
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    • v.37 no.9
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    • pp.533-541
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    • 2015
  • We investigate the Japan's Master Plan of Comprehensive Sewerage System (JMPS) and Lake Biwa basin sewerage and suggest future development direction of the Watershed Sewerage System Maintenance Plan in Korea enforced on February 2, 2013. The JMPS is designed for compliance with the environmental standard for water quality under the Environmental Policy Act. The effluent standards applied in the master plan of Lake Biwa's Sewerage Plan for the Lake Biwa is tougher than the national standards. Therefore the Lake Biwa Baisn Sewerage System was the first in Japan to adopt facilities that perform advanced treatment for nitrogen and phosphorus removal. BOD, SS, T-N and T-P concentrations of discharge water of sewage are 0.9, 0.6, 5.5, 0.06 mg/L, respectively. Especially removal efficiency for BOD is 99.5 percent. It is necessary to study the diversification of the evaluation criteria, cost minimization approach, subsidy system improvement, economic concept of discharge load adjustment system and establishment of basin sewerage concept for the development of the basin sewerage plan in Korea.

Character Analysis by Visual Recognition Elements of Formativeness - focusing on the Characters of 3D Animations, and - (조형성의 시각인지요소를 통한 캐릭터 분석 -3D 애니메이션 <인사이드 아웃>와 <미니언즈>의 캐릭터를 중심으로-)

  • Kim, Hye-Sung
    • Cartoon and Animation Studies
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    • s.42
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    • pp.53-79
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    • 2016
  • The public interest and popularity of animation has already forecasted the value of animation as the leader of pop culture and cultural industry. The trend in animation changed from 2D to 3D animation, a new genre that appeared in the 1990s with the development of computer technology and innovative changes in media, and 3D animation secured its position in the 2000s. Researches on 3D animation are conducted in various ways. Integrating the area it shares with film and the area it shares with design, it is produced and consumed. This study focused on 'formativeness(design)', the basis of character design, and tried to find out how it is recognized by the audience, who actually watch and feel it. Also, it approached basic theory and tried to deduce logic that is easy to understand and can analyze design or formativeness which keeps changing. Lastly, this study regards the parts that viewers are not satisfied with as problems, and tries to find out a developmental direction. Among the animations for theaters that were big hits in 2015, this study focused on the characters of and . It reviewed errors and what was lacking in the previous studies, collected experts' opinions and made adjustment. Using the frame prepared through this process, it conducted a survey on study participants, the viewers, to see how it is perceived by them. Finally, it tried to find out the reasons why the audience felt that way through theoretical reviews and applications.