• 제목/요약/키워드: environmental challenge

검색결과 387건 처리시간 0.03초

A Study of Product Design using Recycled Materials

  • Kim, Kwan-Bae;Chung, Do-Seung;Jang, Jung-Sik
    • International journal of advanced smart convergence
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    • 제9권1호
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    • pp.70-81
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    • 2020
  • Plastics that we use and simply throw away have a life span of about 500 years and barely decompose. The practice of producing and using common plastics needs to be challenged. Until now, they have been useful in the industrial structure of mass production, but it can be said that there is a lack of research into new materials to introduce and apply in terms of material recycling. As a result of this, we have come to the uncomfortable realization of the fact that we cannot incinerate or reuse these precious resources indiscriminately. No matter how well-designed a product is, it has a competitive advantage if production and consumption activities, waste, collection, sorting and treatment are considered in terms of a continuous cycle, and in this respect, Extended Producer Responsibility (EPR) can help. We are implementing the EPR system, and active industrialization in the field of recycling is required, which is also a challenge for producers to participate actively in recycling and seek to save and recycle resources in design and manufacturing. Against this backdrop, We would like to examine the possibilities, through various studies and developments on product design of recyclable materials, which is being conducted mainly in Europe. In particular, we would like to examine the methods, and value of solving environmental problems and the active efforts to achieve this in the design world, and in particular the case of product design using recycled plastics.

SAW의 진폭 모듈화를 통한 실시간 뉴런 자극과 리딩 (Real time neural stimulations and reading by modulating surface acoustic wave amplitude)

  • ;박정근;오효주;박예찬;이기근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2015년도 제46회 하계학술대회
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    • pp.1243-1244
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    • 2015
  • Finding solutions for the disabled is a major challenge for our society. In the case of a disability due to a malfunction of the nervous system, the origin may be accidental, genetic, or induced by environmental factors. This type of loss can cause loss or movement disorders (paraplegia, hemiplegia, quadriplegia, epilepsy, Parkinson's disease, multiple sclerosis, etc.) or malfunction of certain sensory functions (blindness, deafness, chronic pain, etc.). Many alternatives, more technology, have been imported to create interfaces between the human body and an artificial prosthesis in order to restore some functions of the human body. A wireless system, battery neurons probe was developed for one hand reading neural signals in the brain, and on the other hand also able to excite the neuron in the brain using a surface acoustic wave one ports (SAW) delay line reflection.

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Failure analysis of a transmission tower during a microburst

  • Shehata, A.Y.;El Damatty, A.A.
    • Wind and Structures
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    • 제11권3호
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    • pp.193-208
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    • 2008
  • This paper focuses on assessing the failure of one of the transmission towers that collapsed in Winnipeg, Canada, as a result of a microburst event. The study is conducted using a fluid-structure numerical model that was developed in-house. A major challenge in microburst-related problems is that the forces acting on a structure vary with the microburst parameters including the descending jet velocity, the diameter of the event and the relative location between the structure and the jet. The numerical model, which combines wind field data for microbursts together with a non-linear finite element formulation, is capable of predicting the progressive failure of a tower that initiates after one of its member reaches its capacity. The model is employed first to determine the microburst parameters that are likely to initiate failure of a number of critical members of the tower. Progressive failure analysis of the tower is then conducted by applying the loads associated with those critical configurations. The analysis predicts a collapse of the conductors cross-arm under a microburst reference velocity that is almost equal to the corresponding value for normal wind load that was used in the design of the structure. A similarity between the predicted modes of failure and the post event field observations was shown.

Insight into influence of iron addition in membrane bioreactor on gel layer fouling

  • Zhang, Haifeng;Lu, Xin;Yu, Haihuan;Song, Lianfa
    • Membrane and Water Treatment
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    • 제8권6호
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    • pp.543-551
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    • 2017
  • Membrane fouling in membrane bioreactor (MBR) remains a primary challenge for its wider application. The focus of this study to investigate the influence of iron distribution in activated sludge on gel layer fouling in MBR. Significant reduction in the transmembrane pressure (TMP) rise rates was observed in the presence of iron as result of retarding the gel layer formation time. The spatial distribution of iron had a significant impact on the stratification structure of extracellular polymeric substances (EPS) fractions, such as proteins (PN) and polysaccharides (PS). A mitigation of PN or PS from the supernatant to the EPS inner layers was observed in the presence of iron. Compared with the control reactor, the reduction in PN and PS of the supernatant and lower PN/PS rates of the LB-EPS were beneficial to decrease the membrane fouling potential during the gel layer formation. Consequently, the iron addition managed to control gel layer fouling could be a useful strategy in MBR.

Global Sex Differences in Cancer Mortality with Age and Country Specific Characteristics

  • Liu, Lee
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권7호
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    • pp.3469-3476
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    • 2016
  • Background: The cancer research literature suggests that women, especially premenopausal women, have lower cancer mortality rates than men. However, it is unclear if that is true for populations at all age levels in all countries and what factors affect such sex differences. This paper attempts to fill that gap. Materials and Methods: Sex- and country-specific cancer mortality data were statistically analyzed with particular attention to geographic, social, and economic factors that may affect the sex differences. Results: The sex differences were age and country specific, rather than universal. Premenopausal women actually tend to have a disadvantage compared to men or postmenopausal women. Male cancer mortality appears to be the affecting factor in explaining variations in sex differences. Latitude of residence and literacy rate are the affecting factors in cancer mortality and sex differences. African and Latin American countries tend to have a female disadvantage, while East Asian and Eastern European countries are more likely to have a female advantage. Conclusions: The findings challenge the cancer mortality literature and indicate that the sex differences and their possible causes are more complicated than the current literature suggests. They also highlight the urgency of adapting age- and country- specific health systems and policies to better meet the needs of younger women.

현대중공업 중속디젤엔진 힘센엔진 패밀리의 신모델 추가 개발 (EXPANSION OF HYUNDAI'S MEDIUM SPEED DIESEL ENGINE FAMILY, HiMSEN)

  • 김종석;김주태;권오신
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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    • pp.92-100
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    • 2005
  • Since HiMSEN H21/32, a new medium speed diesel engine of Hyundai's own design, was introduced in 2001, Hyundai has added new models of H25/33 and H17/28 into HiMSEN engine family. These two new engines take after faithfully to the original HiMSEN concept of a PRACTICAL engine by Hi-Touch and Hi-Tech. The prototype of H25/33 was developed jointly with Rolls Royce Bergen originally and also introduced in 2001. But most of the engine design have been changed by Hyundai for the commercial versions to be a member of HiMSEN family, which has little interchangeability with the prototype. H17/28 is now under development as the smallest size of the family. This new engine also has the longest stroke of a class engine, which has been proven as the best basis for future environmental challenge. The higher compression ratio of 17 and optimized Miller Timing with Simplified pulse turbocharging system applied all HiMSEN engines as which showed the most practical solution against current heavy fuel combustion issues for the time being before introducing digital control system. This paper describes the design and development of these new HiMSEN engines and also reviews the service experiences of H21/32 and H25/33, which launched successfully.

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노인의 지속가능한 삶을 지원해주는 부엌제품의 유니버설디자인 특성 분석연구 (Analysis of Kitchen Products for Sustainable Living of the Elderly Using Five Universal Design Principles)

  • 이연숙;이수진;민병아;권현주;오소연
    • KIEAE Journal
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    • 제6권4호
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    • pp.57-67
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    • 2006
  • With the coming demographic avalanche as the number of elderly aged 65 and older is expected to double in 20 years in South Korea, the concept of retirement living will be changed in a whole new way. The newest design principles as environmental affordance system for them need to be considered. This study started with the premise that 'Aging in Place' might be the most desirable alternative for the elderly and if so, they may be at greater challenge of living in the home, especially in kitchen. The purpose of this study is to analyze various universal design kitchen products according to five Universal Design criteria with physical or mental characteristics of aging. The five Universal Design principles are 'Supportiveness', 'Adaptability', 'Communicability', 'Pleasantness' and 'Accessibility', which were developed from the previous research. The profile and the trends of the universal design kitchen products were identified with the concrete design examples. The results will be expected to make contributions to developing universal design guidelines for kitchen products, to understanding the nature of universal design paradigm, and to establishing directions for sustainable living of the elderly.

HC저감용 최적 연료분사 시스템에 관한 연구 (A Study on the Fuel Injection System for Optimizing Reduction of HC Emission)

  • 이기형;이창식
    • 한국자동차공학회논문집
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    • 제3권2호
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    • pp.146-156
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    • 1995
  • Growing international concern about environmental issues in recent years has led to new proposals for strengthening exhaust emission standards and fuel economy requirements throughout the world. The low emission vehicle(LEV) standards drawn up by the California Air Resources Board(CARB) in the U.S.A are noticeably stringent To cope with this regulation, a reduction of HC emission is the most important challenge for the automotive industry because HC emission levels are severer than any other components emission levels. In this paper, the apparatus for visulalizing the wall film flow in a intake manifold and the spark plug with optical fiber for detecting the signal from diffusion flame are developed to mal,e the HC formation mechanism clear. High speed camera system is also used to elucidate the correlation wall film flow and the diffusion flame. Using these methods, the effect of fuel injection systems such as injection direction, spray angle, atomised injection on HC emission levels is investigated. Consequently, the optimal fuel injection conditions for minimizing the wall film flow and reducing the HC emission are found through this research.

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한옥의 친환경 특성이 인간에게 미치는 영향요소 분석 (An Analysis of the Natural Characteristics of Hanok that is Beneficial to Human Factors)

  • 안의종
    • KIEAE Journal
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    • 제14권5호
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    • pp.97-102
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    • 2014
  • The beauty of Korean architecture is in its natural beauty. Traditional residence of Korea is architecture that expresses modesty that is embraces the nature. Hanok is designed based on understanding of the nature and responding to it. For this reason, Hanok is a nature-friendly residential space. There are many unique traits of Hanok and one of them is that it is built based on scientific principles. Hanok, without using modern technology and machines, utilizes effectively the natural environment and the climate, e.g., the sun and the wind. Hanok, based on Korea's geographical condition and climate characteristics, have produced a variety of residential houses. The principle of Hanok is not to challenge the nature but embrace and accept it. Furthermore, in Hanok is embedded Korea's traditional philosophy and ideas and it is not simply a simple residential space but also a place for meditation and spiritual training. As the time passes, there are more researches are being done to enhance health in addition to traditional role of protection and convenience. Accordingly, more efforts are being made to bring the nature into human life. Hanok, the traditional residential form of Korea, has environment-friendly architecture and characteristics that could promote human health and enhance our life. Therefore, the nature-oriented philosophy and environmental elements of Hanok should be more systematically studied to take advantage of its architectural advantages and create healthier modern residential culture.

Advancing drag crisis of a sphere via the manipulation of integral length scale

  • Moradian, Niloofar;Ting, David S.K.;Cheng, Shaohong
    • Wind and Structures
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    • 제14권1호
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    • pp.35-53
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    • 2011
  • Spherical object in wind is a common scenario in daily life and engineering practice. The main challenge in understanding the aerodynamics in turbulent wind lies in the multi-aspect of turbulence. This paper presents a wind tunnel study, which focuses on the role of turbulence integral length scale ${\Lambda}$ on the drag of a sphere. Particular turbulent flow conditions were achieved via the proper combination of wind speed, orifice perforated plate, sphere diameter (D) and distance downstream from the plate. The drag was measured in turbulent flow with $2.2{\times}10^4{\leq}Re{\leq}8{\times}10^4$, $0.043{\leq}{\Lambda}/D{\leq}3.24$, and turbulence intensity Tu up to 6.3%. Our results confirmed the general trends of decreasing drag coefficient and critical Reynolds number with increasing turbulence intensity. More interestingly, the unique role of the relative integral length scale has been revealed. Over the range of conditions studied, an integral length of approximately 65% the sphere diameter is most effective in reducing the drag.