• Title/Summary/Keyword: Seeking Solution

Search Result 89, Processing Time 0.026 seconds

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
    • /
    • v.3 no.3
    • /
    • pp.169-179
    • /
    • 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.

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

  • Shim, Young Sub;Heo, Chanhaeng
    • Korean journal of communication and information
    • /
    • v.69
    • /
    • pp.170-194
    • /
    • 2015
  • New institutionalism is one of the research perspective, explaining political, economic, social phenomena through institutions. It is seeking more accurate diagnosis and solution of societal problem. What is good media for community? And how it should be operate? These questions are related to design and improvement of media system. Now we need to better approaching method for higher explanatory power about media institutions. From this context, the purpose of this study is exploring application of new institutionalism to media system. The major findings are as follow: At first, the new institutionalistl approaches can be apply the research fields of media policy/law and media organizations. Two, we suggest main research questions and research methods to each of that. This study has implication as more systematic and integrated approach to the research fields of media institution.

  • PDF

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

  • Cho, Hyong Won
    • The Korean Society of Law and Medicine
    • /
    • v.14 no.1
    • /
    • pp.237-271
    • /
    • 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.

  • PDF

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

  • Chung, Myung-Sun;Ju, Seong-Rae
    • The Research Journal of the Costume Culture
    • /
    • v.15 no.4
    • /
    • pp.551-568
    • /
    • 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.

  • PDF

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

  • Seo, Woo-Soon;Kim, Jae-Hyun;Lee, Ok-Hee
    • Korea Journal of Hospital Management
    • /
    • v.25 no.1
    • /
    • pp.13-20
    • /
    • 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.

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

  • Oh, Suhyun;Kim, Kirang;Hwang, Ji-Yun
    • Korean Journal of Community Nutrition
    • /
    • v.23 no.3
    • /
    • pp.226-233
    • /
    • 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.

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

  • Kim, Sang-Jun
    • Journal of Information Management
    • /
    • v.41 no.4
    • /
    • pp.93-118
    • /
    • 2010
  • This study was aimed to establish a workable strategies to operate KESLI consortium reliably. To encourage the research purposes, it was mainly investigated international literature on current challenges for the e-journals consortium in comparison with the domestic implications. Major issues and challenges are divided to six items by scholarly communication changes and e-journals percentage increase, a big deal for a contract -based consortium pricing model in vogue, a consortium of the price hikes and making budget difficulties, use the standard statistics by the results of the use, archiving and archive security uncertainty, and contracts public availability of such external conditions. As a result, the international challenges of E-journals consortium was similar to KESLI, but the depth of information and research on domestic was weaker than the international research. To see more research and a rational perception based on scientific evidence and alternatives that enable KESLI working in the field was needed to be.

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

  • Oh, Se-Ho
    • Journal of the Korea Convergence Society
    • /
    • v.10 no.11
    • /
    • pp.71-77
    • /
    • 2019
  • This paper defines a multi-selection knapsack problem and presents an algorithm for seeking its optimal solution. Multi-selection means that all members of the particular group be selected or excluded. Our branch-and-bound algorithm introduces a simplex containing the feasible region of the original problem to exploit the fact that the most tightly underestimating function on the simplex is linear. In bounding operation, the subproblem defined over the candidate simplex is minimized. During the branching process the candidate simplex is splitted into two one-less dimensional subsimplices by being projected onto two hyperplanes. The approach of this paper can be applied to solving the global minimization problems under various types of the knapsack constraints.

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

  • Park, Eunhong
    • The Southeast Asian review
    • /
    • v.24 no.2
    • /
    • pp.127-165
    • /
    • 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
    • /
    • v.43 no.5
    • /
    • pp.581-601
    • /
    • 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.