• 제목/요약/키워드: Seeking Solution

검색결과 89건 처리시간 0.024초

Modification of polyamide reverse osmosis membranes seeking for better resistance to oxidizing agents

  • Silva, Lucinda F.;Michel, Ricardo C.;Borges, Cristiano P.
    • Membrane and Water Treatment
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    • 제3권3호
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    • pp.169-179
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    • 2012
  • One of the major limitations in the use of commercial aromatic polyamide thin film composite (TFC) reverse osmosis (RO) membranes is to maintain high performance over a long period of operation, due to the sensitivity of polyamide (PA) skin layer to oxidizing agents, such as chlorine, even at very low concentrations in feed water. This article reports surface modification of a commercial TFC RO membrane (BW30-Dow Filmtec) by covering it with a thin film of poly(vinyl alcohol) (PVA) crosslinked with glutaraldehyde (GA) to improve its resistance to chlorine. Crosslinking reaction was carried out at 25 and $40^{\circ}C$ by using PVA 1.0 wt.% solutions at different GA/PVA mass ratio, namely 0.0022, 0.0043 and 0.013. Water swelling measurements indicated a maximum crosslinking density for PVA films prepared at $40^{\circ}C$ and GA/PVA 0.0043. ATR-FTIR and TGA analysis confirmed the reaction between GA and PVA. SEM images of the original and modified membranes were used to evaluate the surface coating. Chlorine resistance of original and modified membranes was evaluated by exposing it to an oxidant solution (NaClO 300 mg/L, NaCl 2,000 mg/L, pH 9.5) and measuring water permeability and salt rejection during more than 100 h period. The surface modification effectively was demonstrated by increasing the chlorine resistance of PA commercial membrane from 1,000 ppm.h to more than 15.000 ppm.h.

미디어 제도의 신제도주의적 접근을 위한 탐색적 연구 (Exploratory Study on New Institutionalist Approach for Media Institution)

  • 심영섭;허찬행
    • 한국언론정보학보
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    • 제69권
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    • pp.170-194
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    • 2015
  • 신제도주의는 1970년대 이후 정치, 경제, 사회현상에 대하여 제도를 중심으로 보다 정확한 진단과 해법을 추구하는 연구경향을 통칭한다. 공동체에게 좋은 미디어란 무엇이고 어떻게 작동되어야 하는가는 미디어 제도의 설계와 제도 개선에 대한 문제적 성격을 지닌다. 미디어 제도 설계와 제도 개선 문제에 대하여 보다 높은 설명력에 대한 요구에 부응하고 해결방안을 제시할 수 있는 접근 틀이 필요하다. 이러한 배경에서 이 연구는 신제도주의 접근 틀을 통해 미디어 제도에 대한 보다 높은 설명력을 추구하고 이론화를 위한 활용방안을 탐색하였다. 주요 결과로 첫째 신제도주의 접근 틀은 미디어 정책 법제, 미디어조직 연구 분야에 보다 잘 활용될 수 있다. 둘째, 미디어정책 법제 연구와 미디어 조직연구에서 다룰 주요 연구문제와 연구방법을 제시하였다. 이 연구는 미디어 제도에 대하여 보다 체계적이고 통합적인 하나의 연구 방법으로서 신제도주의 접근법의 활용방안을 제시하였다는 점에서 의의를 갖는다. 미디어 제도를 보다 잘 설명할 수 있는 접근법으로 향후 다양한 미디어 제도 연구 분야에 활용될 수 있기를 기대한다.

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우리나라 보건의료법의 현황과 과제 - 법정책학적 연구방법론을 중심으로 - (The Present State and Subject of Health Care Law System in Korea)

  • 조형원
    • 의료법학
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    • 제14권1호
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    • pp.237-271
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    • 2013
  • There is the limit of the traditional legal hermeneutics and fragmentary or individual theoretical legal approach to suggest the desirable solution of Korean health care law system to have many issues. Law & politics research is the legal research method to suggest the resonable understanding and seeking the measures through various approach, decide and evaluate that the legal methods can be functioned as the optimum system design. Law & politics research has some procedure. 1. It is demanded to catalog the comparison target of legal system by its topic. 2. It is demanded to compare it with Korean situation. 3. The realistic and empirical legal research to the compared policy alternatives is needed. 4. Reflecting the results of this research work, the desirable policy idea must be adopted. 5. The accomplishment of this policy idea must be come true as a specific legislation through interest coordination. 6. This plan must be come into force and the feedback to effect of society must be examined closely. Here I will review generally the contribution of law & politics research to health care law system because of the problem of time and the insufficiency of law & politics research. The constitutional consideration is important to support the interest coordination because of the shortage of resources. The comparative law research can compare our health care system with those of other countries and seek some desirable alternatives. If we discuss the law system plan in a long time and synthetically from different perspectives, more desirable helath care law system can be deducted.

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대학생들의 인터넷 패션 쇼핑몰에 대한 서비스 불평과 회복 지각에 관한 탐색적 연구 (An Exploratory Study on University Student's Service Complaint and Recovery Perception toward Internet Fashion Shopping Mall)

  • 정명선;주성래
    • 복식문화연구
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    • 제15권4호
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    • pp.551-568
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    • 2007
  • The purposes of this study were to identify factors of dissatisfaction and complaining behavior in internet fashion shopping mall, and to investigate constructs of service recovery for solution to this problems. Data were obtained from 201(male: 87, female: 114) internet fashion shopping mall consumer who have experiences of dissatisfaction and complaining behavior after buying products, and were analyzed using by descriptive analysis, factor analysis, Cronbach' $\alpha$, t-test. The results were as follows. First, the most response(80.4% of reponses) was experience to dissatisfaction through internet fashion shopping mall, and the most dissatisfied items were blouse, sweater, T-shirt in upper garment. Also, in men's case, the most satisfied price zone was not exceeding $30,000{\sim}50,000\;won$ and in women's case, it was not exceeding $20,000{\sim}30,000\;won$. Second, 7 factors of dissatisfaction(called quality, payment, delivery, price, interaction, returning/changing/refunding, contract) were identified after purchasing fashion products from internet shopping mall. 3 factors of complaining behavior(called private action, legal action, remedial seeking action) were investigated. Third, constructs of perceived service recovery were extracted from literature review: perceived interaction and justice. Perceived interaction were categorized into two factors: the interaction on the part of the consumer, the interaction in the part of the shopping mall. And perceived justice were categorized into three factors: interactional justice, distributive justice, procedural justice. Usually, university students were likely to take a serious view of service recovery through interaction and justice with internet fashion shopping mall.

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지역에 따른 의료이용의 차이 분석 (An Analysis Of The Differences In Medical Use By Region)

  • 서우순;김재현;이옥희
    • 한국병원경영학회지
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    • 제25권1호
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    • pp.13-20
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    • 2020
  • Purposes: This study has the purpose to the improvement of health promotion for local residents through delivery of high-quality medical service by improving imbalance of medical use and seeking an improvement plan for accessibility of effective medical service by understanding the pattern of medical use by region. Methodology: As for the method, this study derived results at the significance level of p<0.05 through chi square test(χ2 test) and Generalized Estimating Equation(GEE) SAS 9.4 version by using the data of the 7th Korean Longitudinal Study of Ageing 2018. Findings: Study results show that local residents use medical service such as hospitalization care and outpatient visit more as compared to the residents in Gyeonggi-do/large or medium-sized cities. The more the number of chronic disease, the more they select hospitalization care rather than outpatient visit. Results also show that patients engaged in labour tend to select outpatient treatment rather than hospitalization treatment. Meanwhile, severity of disease turned out to be higher amongst medical care beneficiaries than that of national health insurance patients when comparing the types of medical security. Practical Implications: In stead of solving the problem of the difference in medical use by region from the aspect of income and economic level, an integrative solution shall be provided putting viewpoint on the social phenomenon suited to the changes of the times. This study suggests a plan for using a health and medical community care center that acts as a gate keeper of regional medical service.

건강매점을 이용한 청소년 영양관리의 현황과 향후 개선 방안 : 매점 이용자 측면에 대한 질적 연구 (Current Status and Suggested Future Directions of Nutrition Intervention using Healthy School Tuck Shops: the Teenage Perspective)

  • 오수현;김기랑;황지윤
    • 대한지역사회영양학회지
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    • 제23권3호
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    • pp.226-233
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    • 2018
  • Objectives: This study was conducted to investigate the current status and to suggest future directions for health management of teenagers who use healthy school tuck shops to improve teenagers' eating habits while reducing and preventing obesity. Methods: A total of 29 students (16 middle school students and 13 high school students) took part in the interview for this study, and the interview was conducted for each school's focus group by using qualitative research methodology. Results: The current status of using healthy school tuck shops and suggested future directions were divided into two categories. Personal barriers such as discrepancies between personal perceptions and behaviors and lack of food choice suitable to individual tastes can be solved by rebuilding the operating system to provide intuitive promotion of behavior and customized products through improvements in existing products and new product development. A lack of consistent management from low utilization convenience and difficulty in maintaining a constant purchase price can be handled by establishing a solution to restricted physical access for products, as well as seeking profit by improving distribution costs via continuous cooperation between the school and community. Conclusions: Continuous funding and a system that reflects the needs and preferences of healthy school tuck shop users should be applied for sustainable operation of healthy school tuck shops to improve teenagers' eating habits.

전자저널 컨소시엄의 당면과제와 해결방안 모색 (Challenges and Solutions of Electronic Journal Consortium)

  • 김상준
    • 정보관리연구
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    • 제41권4호
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    • pp.93-118
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    • 2010
  • 본 연구는 KESLI 컨소시엄을 안정적으로 운영하기 위한 실천 가능한 대응 전략을 마련하도록 유도하려는 연구목적에 따라 외국 문헌연구를 통해 전자저널 컨소시엄의 당면과제를 국내와 비교하여 해결방안을 도출하였다. 연구된 주요 당면과제는 학술커뮤니케이션 변화와 전자저널 비중 증대, 빅딜 계약중심의 컨소시엄 가격 모델 성행, 컨소시엄의 가격 인상과 예산 확보 곤란, 이용통계 표준화에 의한 분석 결과의 활용, 아카이빙 및 아카이브 보장의 불확실성, 계약과 서비스 조건의 외부 공개 가능성 등 6개 항목으로 정리하였다. 연구결과 국내외 전자저널 컨소시엄 연구동향과 이슈는 대체로 유사하지만 내용과 연구의 깊이는 달라 국내에서 전자저널 컨소시엄에 대해 더 많은 연구와 보고가 KESLI를 중심으로 이루어져 합리적 인식과 과학적 근거에 기반한 문제제기와 대안제시가 실무현장에서 더 활성화될 필요가 있었다.

다중 선택 배낭 제약식 하에서의 오목 함수 최소화 문제 (An Concave Minimization Problem under the Muti-selection Knapsack Constraint)

  • 오세호
    • 한국융합학회논문지
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    • 제10권11호
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    • pp.71-77
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    • 2019
  • 본 연구에서는 다중 선택 배낭 모형의 최적해를 찾는 해법을 제시하고자 한다. 다중 선택은 동일한 집단에 소속된 구성원들이 동시에 선택되거나 동시에 배제되는 상황에서 관찰된다. 각 집단 간 관련성의 측정치인 오목 함수가 의사결정기준으로 설정되었다. 다중 선택은 비선형 제약식으로 모형화 되는데 일반 배낭 제약식으로 변환될 수 있다. 따라서 최적 해법 개발을 위해 오목함수 최소화 문제와 배낭 문제의 일반적인 해법들에서 채택하고 있는 분지 한계 접근법을 이용하였다. 단체상에서 오목함수를 가장 근접하게 하한추정하는 함수가 1차식이라는 사실이 한계 전략의 이론적 토대가 된다. 또한 하위 단계에서도 1차식 목적함수가 유일하게 결정되도록, 후보 단체를 두 개의 초평면에 투사시킴으로써 1차원 낮은 두 개의 하위 단체로 분할하는 방법이 분지 전략의 핵심이다. 앞으로 본 연구의 결과는 다양한 형태의 배낭 제약식 하에서의 오목 함수 최소화 문제의 해법을 개발하는데 응용될 수 있을 것이다.

민족혁명과 시민혁명: 타이와 미얀마 (National Revolution vs. Civil Revolution: The Comparison between Thailand and Myanmar)

  • 박은홍
    • 동남아시아연구
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    • 제24권2호
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    • pp.127-165
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    • 2014
  • This article regards the phase of political confrontations in Thailand and Burma as a prolonged and inconclusive political struggle between national revolution forces and civil revolution forces. It argues that in Thai case, anti-monarchy constitutional revolution has led to a right-wing national revolution based on state nationalism consolidating capitalist economic system by Sarit's military coup, while in Burmese case, anti-British imperialism movement in colonial era has resulted in a left-wing national revolution grounded on state nationalism associating with socialist economic system by Ne Win's military coup. It is also interesting to note that the two cases experienced state nationalism denying autonomous civil society as a process of nation-building in spite of their contrasting ideologies. In both cases, it became inevitable to have national revolution forces clinging to official nationalism and state nationalism confronting with civil revolution forces seeking popular nationalism and liberal nationalism. In particular, unlike Burmese society, Thai society, without colonial history has never experienced a civil war mobilizing anti-colonial popular nationalism including ethnic revolt. This article considers Dankwart Rustow's argument that national unity as a background condition must precede all the other phases of democratization, but that otherwise its timing is irrelevant. In this context, Thai democratization without national unity which began earlier than Burmese is taking a backward step. For the time being, there would be no solution map to overcome severe political polarization between the right-wing national revolution forces defending official nationalism cum state nationalism and the civil revolution forces trying to go beyond official nationalism towards popular nationalism cum liberal nationalism. In contrast, paradoxically belated Burmese democratization has just taken a big leap in escaping from serious and inconclusive nature of political struggle between the left-wing national revolution forces to defend official nationalism cum state nationalism and civil revolution based on popular nationalism cum liberal nationalism towards a reconciliation phase in order to seek solutions for internal conflicts. The two case studies imply that national unity is not a background condition, but a consequence of the process of political polarization and reconciliation between national revolution forces and civil revolution forces.

Axisymmetric vibration analysis of a sandwich porous plate in thermal environment rested on Kerr foundation

  • Zhang, Zhe;Yang, Qijian;Jin, Cong
    • Steel and Composite Structures
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    • 제43권5호
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    • pp.581-601
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    • 2022
  • The main objective of this research work is to investigate the free vibration behavior of annular sandwich plates resting on the Kerr foundation at thermal conditions. This sandwich configuration is composed of two FGM face sheets as coating layer and a porous GPLRC (GPL reinforced composite) core. It is supposed that the GPL nanofillers and the porosity coefficient vary continuously along the core thickness direction. To model closed-cell FG porous material reinforced with GPLs, Halpin-Tsai micromechanical modeling in conjunction with Gaussian-Random field scheme is used, while the Poisson's ratio and density are computed by the rule of mixtures. Besides, the material properties of two FGM face sheets change continuously through the thickness according to the power-law distribution. To capture fundamental frequencies of the annular sandwich plate resting on the Kerr foundation in a thermal environment, the analysis procedure is with the aid of Reddy's shear-deformation plate theory based high-order shear deformation plate theory (HSDT) to derive and solve the equations of motion and boundary conditions. The governing equations together with related boundary conditions are discretized using the generalized differential quadrature (GDQ) method in the spatial domain. Numerical results are compared with those published in the literature to examine the accuracy and validity of the present approach. A parametric solution for temperature variation across the thickness of the sandwich plate is employed taking into account the thermal conductivity, the inhomogeneity parameter, and the sandwich schemes. The numerical results indicate the influence of volume fraction index, GPLs volume fraction, porosity coefficient, three independent coefficients of Kerr elastic foundation, and temperature difference on the free vibration behavior of annular sandwich plate. This study provides essential information to engineers seeking innovative ways to promote composite structures in a practical way.