• 제목/요약/키워드: Technology alternative

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계절 변화에 대한 예비 중등교사의 대안개념의 구조 (THE STRUCTURES OF THE ALTERNATIVE CONCEPTIONS OF PRESERVICE SECONDARY TEACHERS ON SEASONAL CHANCES)

  • 오준영;박성호
    • Journal of Astronomy and Space Sciences
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    • 제22권1호
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    • pp.69-88
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    • 2005
  • 본 연구에서는 예비 중등교사들을 대상으로 '계절 변화의 설명'에 대한 대안 개념과 그 개념에 영향을 주는 요소들을 조사하였다. 본 연구에 참여한 예비교사는 대학교 과학교육학부 2학년 23명, 3학년 23명, 그리고 4학년 28명으로 총 74명이다. 자료 수집은 지필 검사와 개별 면담을 통해 이루어졌다. 연구 결과, 예비 중등교사들은 계절변화 설명에 대한 과학적 개념과 불일치하는 대안 개념들을 가지고 있었으며, '거리 이론'이 그들의 설명에 가장 큰 영향을 미치는 것으로 나타났다. 또한 예비 중등교사들이 갖는 '계절변화'의 대안개념의 구조와 근원을 알아보기 위하여 그 개념들을 형성하는 틀 이론과 특정 이론을 집중적으로 탐색하였다. 끝으로 연구 결과와 관련된 예비 교사교육에의 시사점을 논하였다.

중소기업 대안금융으로서 플랫폼 금융의 모색 (Seeking Platform Finance as an Alternative Model of Financing for Small and Medium Enterprises in Korea)

  • 정재만;박재성
    • 기업가정신과 벤처연구
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    • 제20권3호
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    • pp.49-68
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    • 2017
  • 플랫폼 금융은 데이터 분석과 플랫폼을 이용한 매칭이라는 새로운 자금조달 방식을 제시함으로써 중소기업의 대안금융으로 부상하고 있다. 이 사업의 본질은 빅데이터를 이용한 위험평가와 투자자의 위험-수익 선호(risk-return preference)를 적절히 반영할 수 있는 위험분산 기술을 금융업에 적용한 것이다. 이로써 소상공인을 위한 소액금융, 중소기업의 운전자본(working capital) 조달을 위한 공급망 금융의 형태로 기존 금융의 대안으로 부상하고 있다. 한국의 플랫폼 금융은 이 같은 가능성에도 아직 유치 단계(infant stage)이며, 정책적 지원을 필요로 한다. 이는 다음과 같이 요약할 수 있다. "기관 및 공공 투자참여", 플랫폼 금융의 민간 자금유입(crowd-in)을 위한 정책금융의 씨앗자금(seed money) 공급, "수용적 규제체계", 영국의 샌드박스와 같이 새로운 사업에 대한 한시적 규제 유예, "데이터 개방 확대", 재량적인 데이터 공유의 허용, "대안투자 수단의 보급", 저금리시대의 대안투자 수단으로서 플랫폼 금융 육성.

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Effect of Sodium-Alternative Curing Salts on Physicochemical Properties during Salami Manufacture

  • Yim, Dong-Gyun;Shin, Dong-Jin;Jo, Cheorun;Nam, Ki-Chang
    • 한국축산식품학회지
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    • 제40권6호
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    • pp.946-956
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    • 2020
  • To identify the effect of sodium-alternative curing salts on the quality properties of salami through the ripening process, four salami treatments were prepared with different curing salts, T1 (-control, NaCl 1.9%), T2 (+control, NaCl 1.9%+NaNO2 0.01%), T3 (KCl 1.9%+NaNO2 0.01%), and T4 (MgCl2 1.9%+NaNO2 0.01%), under 40 days ripening conditions. Sodium-alternative salts (T3 or T4) showed characteristically different quality traits compared with T2. Especially, T3 had lower pH, water activity, volatile basic nitrogen, and lipid oxidation after 20 days of ripening period, compare with T2 or T4 (p<0.05). Sodium nitrite had critical impact on increased a* values, and T3 showed higher a* values compared with T2 or T4 (p<0.05). Sodium nitrite reduced initial growth of coliforms but sodium-alternative salts did not affect microbial growth patterns. T2-T4 containing sodium nitrite had higher content of umami nucleotide flavor compounds compared with T1, regardless of the chlorine salt species. The combined use of sodium-alternative curing salts and minimal sodium nitrite was found to be an applicable strategy on development of low sodium salami without a trade-off of the product quality.

Combustion Characteristics of an Agricultural Diesel Engine using Biodiesel Fuel

  • Ryu, Kyunghyun;Oh, Youngtaig
    • Journal of Mechanical Science and Technology
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    • 제18권4호
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    • pp.709-717
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    • 2004
  • Biodiesel has great potential as an alternative fuel for diesel engines that would reduce air pollution. It is a domestically produced, renewable fuel that can be manufactured from fresh or used vegetable oils, or from animal fats. In this study, a biodiesel fuel derived from rice bran oil was tested as an alternative fuel for agricultural diesel engines. The emissions were characterized for both neat and blended biodiesel fuels, and for conventional diesel fuel. Since this biodiesel fuel contained 11 % oxygen, it strongly influenced the combustion process. The use of biodiesel fuel resulted in lower carbon monoxide, carbon dioxide, and smoke emissions, without any increase in nitrous oxide emissions. The study demonstrated that biodiesel fuel could be effectively used as a renewable and environmentally innocuous fuel for agricultural diesel engines.

Antioxidant, Antimicrobial, and Cancer Cell Proliferative Inhibition Activities of Propolis

  • Kang, Ho-Jin;Ko, Ki-Wan;Lee, Ok-Hwan;Lee, Boo-Yong
    • Food Science and Biotechnology
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    • 제18권4호
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    • pp.1042-1045
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    • 2009
  • A commercial propolis was investigated in terms of its antioxidant, antimicrobial, and antiproliferative activities. The contents of total phenol and flavonoid of propolis were 8.3 and 6.6 mg, respectively. The reducing power of the propolis increased with concentration increasing. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was shown at 82.70% in 1,000 ${\mu}g/mL$ of the propolis. 2,2'-Azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging effect of antioxidant activity on the propolis was 35.64 g/sample. The propolis showed high antimicrobial activity against Bacillus cereus at all concentration of propolis. All of the cancer cell lines have 53-73% as effective growth inhibition. These results showed that the commercial propolis has potential antioxidant, antimicrobial, and cancer cell proliferative inhibition activities thus, propolis can be applied to the functional food, pharmaceutical, and cosmetic industry.

What Is Integrative Medicine?

  • Jung, Seungpil
    • Journal of Yeungnam Medical Science
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    • 제30권2호
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    • pp.79-82
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    • 2013
  • The demand for complementary and alternative medicine (CAM) is increasing worldwide. High-technology medicine is not always effective and is often accompanied by neglected self-care and high cost. Also, conventional medicine has become dependent on expensive technological solutions to health problems. Integrated medicine is not simply a synonym for complementary medicine. It involves the understanding of the interaction of the mind, body, and spirit and how to interpret this relationship in the dynamics of health and disease. Integrative medicine shifts the orientation of the medical practice from a disease-based approach to a healing-based approach. In South Korea, CAM education was first provided 20 years ago, and integrative medicine is becoming part of the current mainstream medicine. Increasing numbers of fellowships in integrative medicine are being offered in many academic health centers in the U.S. Also, it has emerged as a potential solution to the American healthcare crisis and chronic diseases, which are bankrupting the economy. It provides care that is patient-centered, healing-oriented, emphasizes the therapeutic relationship, and uses therapeutic approaches originating from conventional and alternative medicine.

Assessing Alternative Renewable Energy Policies in Korea's Electricity Market

  • KIM, HYUNSEOK
    • KDI Journal of Economic Policy
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    • 제41권4호
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    • pp.67-99
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    • 2019
  • This paper, focusing on the renewable portfolio standard (RPS), evaluates alternative renewable energy policies. We propose a tractable equilibrium model which provides a structural representation of Korea's electricity market, including its energy settlement system and renewable energy certificate (REC) transactions. Arbitrage conditions are used to define the core value of REC prices to identify relevant competitive equilibrium conditions. The model considers R&D investments and learning effects that may affect the development of renewable energy technologies. The model is parameterized to represent the baseline scenario under the currently scheduled RPS reinforcement for a 20% share of renewable generation, and then simulated for alternative scenarios. The result shows that the reinforcement of the RPS leads to higher welfare compared to weakening it as well as repealing it, though there remains room to enhance welfare. It turns out that subsidies are welfare-inferior to the RPS due to financial burdens and that reducing nuclear power generation from the baseline yields lower welfare by worsening environmental externalities.

Group Decision Making Using Intuitionistic Hesitant Fuzzy Sets

  • Beg, Ismat;Rashid, Tabasam
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제14권3호
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    • pp.181-187
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    • 2014
  • Dealing with uncertainty is always a challenging problem. Intuitionistic fuzzy sets was presented to manage situations in which experts have some membership and non-membership value to assess an alternative. Hesitant fuzzy sets was used to handle such situations in which experts hesitate between several possible membership values to assess an alternative. In this paper, the concept of intuitionistic hesitant fuzzy set is introduced to provide computational basis to manage the situations in which experts assess an alternative in possible membership values and non-membership values. Distance measure is defined between any two intuitionistic hesitant fuzzy elements. Fuzzy technique for order preference by similarity to ideal solution is developed for intuitionistic hesitant fuzzy set to solve multi-criteria decision making problem in group decision environment. An example is given to illustrate this technique.

수요가 불확실한 환경에서 대체공정계획을 고려한 셀형제조시스템 설계 (Design of Cellular Manufacturing System with Alternative Process Plans under Uncertain Demand)

  • 고창성;이상헌;이양우
    • 대한산업공학회지
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    • 제24권4호
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    • pp.559-569
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    • 1998
  • Cellular manufacturing system (CMS) has been recognized as an alternative to improve manufacturing productivity in conventional batch-type manufacturing systems through reducing set-up times, work-in-process inventories and throughput times by means of group technology. Most of the studies on the design of CMS assumed that each part has a unique process plan, and that its demand is known as a deterministic value despite of the probabilistic nature of the real world problems. This study suggests an approach for designing CMS, considering both alternative process plans and uncertain demand. A mathematical model is presented to show how to minimize the expected amortized and operating costs satisfying these two relaxations. Four heuristic algorithms are developed based on tabu search which is well suited for getting an optimal or near-optimal solution. Example problems are carried out to illustrate the heuristic algorithms and each of them is compared with the deterministic counterpart.

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STEPS TOWARD HALON PHASE-OUT, PROPOSED SUBSTITUTES AND ALTERNATIVE FOR FIXED FIRE SUPPRESSION SYSTEMS

  • Msc.Fpe, Suprapto;Rahardja, Nugraha-B
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.564-572
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    • 1997
  • Following the ratification of Vienna Convention for Ozone Layer Protection and Montreal Protocol, Indonesia will implement the phasing-out of to halon at end 1996. Questions are increasing especially from the users where halon has used for many years as the most effective fire extinguishing agent, concerning halon substitutes, alternative systems as well as the handling and utilization of the existing halon. Halon can still be used for critical and essential uses, however, such usage has been gradually eliminated, due to the emergence of halon-like replacement. A concept of halon banking system is proposed to considered, taking into account several aspects such as enforced regulation, institutional involvement technology as well as financing. This paper gives a general overview regarding phase-out implementation, alternative extinguishing systems and concept on halon banking system with special reference to Indonesian case.

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