• 제목/요약/키워드: Technical Issue

검색결과 535건 처리시간 0.027초

숲가꾸기 산물을 이용한 펠릿의 원료 적성 연구 (Exploration of Alternative Raw materials to Forest Biomass for Pellets)

  • 김성호;김철환;안병일;이지영;;;박현진;곽혜정;김경철
    • 한국펄프종이공학회:학술대회논문집
    • /
    • 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
    • /
    • pp.171-178
    • /
    • 2011
  • During the last decades, global warming from the increased amount of greenhouse gases, mainly carbon dioxide has become a major political and scientific issue. Burning fossil fuels (natural gas, coal and oil) releases $CO_2$, which is also a major cause of global warming. Among the clean environment, wood pellets are considered as promising renewable fossil fuels because of clean burning characteristics, reduction of particulate and NOx emission from combustion. In Korea, more than 50% pellets have to be imported every year because of shortage of feedstocks. On the other hand, about 80% of wood pulps are greatly dependent upon overseas products due to limited forest resources. Under this situation, this study explored how efficiently we have to use forest biomass instead of total dependence on wood as raw materials for pellets.

  • PDF

고트프리트 젬퍼(Gottfried Semper)와 칼 뵈티허 (Karl B$\ddot{o}$tticher)의 텍토닉 개념 비교 (A Comparative Study on the Theory of Tectonics between Gottfried Semper and Karl B$\ddot{o}$tticher)

  • 정인하
    • 건축역사연구
    • /
    • 제7권4호
    • /
    • pp.77-91
    • /
    • 1998
  • The theory of tectonic appeared in the midst of 19th century as German architects adopted new materials and structural technology, invented by creative engineers, into architectural design. This does not merely mean a technical problem but concern the redefinition of architecture in term of an aesthetic, cultural, and ontological identity. Furthermore it alluded to a desire on the part of architectural theorists to actualize artistic and spiritual goals out of new constructional necessities. Because of their complex discourse that assumed the possibility of communication between philosophical and technical aspects, between ideal and real concerns, tectonics becomes until now the most important issue in architecture. The concept of tectonic was intensively investigated by Gottfried Semper's and Karl B$\ddot{o}$tticher architectural writings. They contributed to clarify the principle aspects of tectonic within architectural, philosophical, and anthropological discourses of 19th century. Gottfried Semper stressed an understanding of how architecture took on physical form in earliest human culture. He placed great importance on the artistic expression of materials. But unlike Semper who argued the cladding of the structural frame by decorative wall system, Karl Botticher required maximum visibility of structural frame. This represents the different positions between Gottfried Semper and Karl Botticher

  • PDF

Recommendation for the modelling of 3D non-linear analysis of RC beam tests

  • Sucharda, Oldrich;Konecny, Petr
    • Computers and Concrete
    • /
    • 제21권1호
    • /
    • pp.11-20
    • /
    • 2018
  • The possibilities of non-linear analysis of reinforced-concrete structures are under development. In particular, current research areas include structural analysis with the application of advanced computational and material models. The submitted article aims to evaluate the possibilities of the determination of material properties, involving the tensile strength of concrete, fracture energy and the modulus of elasticity. To evaluate the recommendations for concrete, volume computational models are employed on a comprehensive series of tests. The article particularly deals with the issue of the specific properties of fracture-plastic material models. This information is often unavailable. The determination of material properties is based on the recommendations of Model Code 1990, Model Code 2010 and specialized literature. For numerical modelling, the experiments with the so called "classic" concrete beams executed by Bresler and Scordelis were selected. It is also based on the series of experiments executed by Vecchio. The experiments involve a large number of reinforcement, cross-section and span variants, which subsequently enabled a wider verification and discussion of the usability of the non-linear analysis and constitutive concrete model selected.

턴키방식 플랜트계약의 실무상 유의점에 관한 연구 - ICC 표본 계약서의 해설을 중심으로 - (A Study on the Practical Suggestions in the Contract for the Turnkey Supply of an Industrial Plant - Focused on the Commentary of ICC Model Contract -)

  • 오원석;이기옥
    • 무역상무연구
    • /
    • 제53권
    • /
    • pp.3-29
    • /
    • 2012
  • This article examines the Practical Suggestions in the Contract for the Turnkey Supply of an Industrial Plant based on a study focused on the commentary of "ICC Model Contract" clause which is encouraged by ICC. Especially practical issues are inquired into on business and legal perspective as follows. First, in regard to supply of technical documentation, equipment and spare parts, it is important to supplier and purchaser to agree on obtaining technical documents necessary for installing and operating plant, and also components necessary for it's maintenance. Second, it is about erection, testing, taking over and training chapter. Both parties need to agree about the process of the arrival of equipments and assembly conducted by the supplier and following examination and also training purchaser to operate it Third, when it comes to price, payment conditions, bank guarantees, parties are to make decision on the pricing, payment conditions and currency of contract-payment. Lastly, it is necessary to reach an agreement of the issue of whether it is to be defined as delay or non-performance of the contract and also it's consequences about rights and obligation.

  • PDF

기후변화 대응을 위한 국내 제지산업의 환경 경영 방안 (Environmental management strategies of Korean paper industry for response to climate change)

  • 김동섭;성용주;김세빈;이준우;박관수
    • 펄프종이기술
    • /
    • 제45권4호
    • /
    • pp.42-51
    • /
    • 2013
  • Climate changes have become the major issue for the sustainable society and the various regulation has been established for promoting low carbon and green growth in Korea. The paper industry as a large comsumer of energy is forced to cope with these regulation. In this study, the various examples were investigated for providing the basic schemes to develop environmental management strategies of Korean paper industry. The various cases to follow carbon economic were introduced and were categorized into five ways, for example, the carbon capture projects such as reforestation, the increasing the process efficiency, the resource recovery form process waste, the cogeneration systems, the application of non-woody biomass.

Sustainable retrofit design of RC frames evaluated for different seismic demand

  • Zerbin, Matteo;Aprile, Alessandra
    • Earthquakes and Structures
    • /
    • 제9권6호
    • /
    • pp.1337-1353
    • /
    • 2015
  • Seismic upgrading of existing structures is a technical and social issue aimed at risk reduction. Sustainable design is one of the most important challenges in any structural project. Nowadays, many retrofit strategies are feasible and several traditional and innovative options are available to engineers. Basically, the design strategy can lead to increase structural ductility, strength, or both of them, but also stiffness regulation and supplemental damping are possible strategies to reduce seismic vulnerability. Each design solution has different technical and economical performances. In this paper, four different design solutions are presented for the retrofit of an existing RC frame with poor concrete quality and inadequate reinforcement detailing. The considered solutions are based on FRP wrapping of the existing structural elements or alternatively on new RC shear walls introduction. This paper shows the comparison among the considered design strategies in order to select the suitable solution, which reaches the compromise between the obtained safety level and costs during the life-cycle of the building. Each solution is worked out by considering three different levels of seismic demand. The structural capacity of the considered retrofit solutions is assessed with nonlinear static analysis and the seismic performance is evaluated with the capacity spectrum method.

전력산업 미래 유망기술 발굴 방법론 연구 (Study on Emerging Technologies in Electric Power Industry)

  • 박수만
    • KEPCO Journal on Electric Power and Energy
    • /
    • 제2권2호
    • /
    • pp.317-325
    • /
    • 2016
  • In recent years, the U.S, Japan, Europe and other developed countries are strategically developing technologies in order to prepare for paradigm shift affecting the electric power industry in a preemptive way. In particular, a chance for new business models and innovation in the electric power industry would rapidly increase with convergence of various technologies including Information and communication technologies. This study gathered up the theories and methodologies, and sorted out emerging technologies for the electric power industry with those theories. In order to find the emerging technologies, first, we identified the possible key issues of the electric power industry in the future using four mining techniques such as STEEP. Second, we drew agenda related with each key issue. Third, we organized candidates of the emerging technologies for solving the agenda and set the priority after evaluating the possibility of technical innovation and business. Finally, we selected the top fourteen of emerging technologies and assessed their feasibility. This study has a methodological significance because the emerging technologies were developed with a market-oriented approach rather than technical-push one that has been primarily used in another studies. The results of this study are able to be used in establishment of technology policy and R&D planning in the electric power industry.

An overview of the national immunization policy making process: the role of the Korea expert committee on immunization practices

  • Cho, Hee-Yeon
    • Clinical and Experimental Pediatrics
    • /
    • 제55권1호
    • /
    • pp.1-5
    • /
    • 2012
  • The need for evidence-based decision making in immunization programs has increased due to the presence of multiple health priorities, limited human resources, expensive vaccines, and limited funds. Countries should establish a group of national experts to advise their Ministries of Health. So far, many nations have formed their own National Immunization Technical Advisory Groups (NITAGs). In the Republic of Korea, the Korea Expert Committee on Immunization Practices (KECIP), established by law in the early 1990s, has made many important technical recommendations to contribute to the decline in vaccine preventable diseases and currently functions as a NITAG. It includes 13 core members and 2 non-core members, including a chairperson. Core members usually come from affiliated organizations in internal medicine, pediatrics, obstetrics, microbiology, preventive medicine, nursing and a representative from a consumer group, all of whom serve two year terms. Non-core members comprise two government officials belonging to the Korea Centers for Disease Control and Prevention (KCDC) and the Korea Food and Drug Administration. Meetings are held as needed, but at least twice a year, and sub-committees are formed as a resource for gathering, analyzing, and preparing information for the KECIP meetings. Once the sub-committees or the KCDC review the available data, the KECIP members discuss each issue in depth and develop recommendations, usually by a consensus in the meeting. The KECIP publishes national guidelines and immunization schedules that are updated regularly. KECIP's role is essentially consultative and the implementation of their recommendations may depend on the budget or current laws.

Estimation of greenhouse gas emissions: An alternative approach to waste management for reducing the environmental impacts in Myanmar

  • Tun, Maw Maw;Juchelkova, Dagmar
    • Environmental Engineering Research
    • /
    • 제24권4호
    • /
    • pp.618-629
    • /
    • 2019
  • Along with growing population and economic development, increasing waste generation rates in developing countries have become a major issue related to the negative impacts of waste management on the environment. Currently, the business-as-usual waste management practices in Myanmar are largely affecting the environment and public health. Therefore, this study developed an alternative approach to waste management for reducing the environmental impacts in Myanmar by highlighting the greenhouse gas (GHG) emissions from business-as-usual practices and three proposed scenarios during 2018-2025. The calculation methods of the Intergovernmental Panel on Climate Change and Institute for Global Environmental Strategies were used for estimating the GHG emissions from waste management. It was estimated that the current waste management sector generated approximately 2,000 gigagrams of CO2-eq per year in 2018, trending around 3,350 Gg of CO2-eq per year in 2025. It was also observed that out of the proposed scenarios, Scenario-2 significantly minimized the environmental impacts, with the lowest GHG emissions and highest waste resource recovery. Moreover, the GHG emissions from business-as-usual practices could be reduced by 50% by this scenario during 2018-2025. The target of the similar scenario could be achieved if the local government could efficiently implement waste management in the future.

3차원 CAD에서 STEP Part111을 통한 AP224 특징형상 데이터 번역 (AP224 based Feature Translation from 3D CAD through STEP Part111)

  • 김준환
    • 한국CDE학회논문집
    • /
    • 제11권4호
    • /
    • pp.303-314
    • /
    • 2006
  • The exchange of CAD (Computer Aided Design) models between different CAD systems and to downstream applications such as manufacturing has become very important to modem industry. One serious current issue is that the process cannot automatically import existing 3-D solid models in a variety of commercial CAD formats into the process without manually re-mastering the model in current standard including "SIEP AP(Application Protocol) 203 Edition 1" To fully integrate technical data from the design agency to the shop floor, design intent and validated 3D geometry of feature based parametric CAD model should be brought into the standardized processes. To overcome this limitation, AP203 Edition 2 (Ed.2) and its related STEP parts such as Part55, Part108, Part109, Part111 and Part112 are starting to be available to handle this problem. The features in Part111 are harmonized with the machining features available in AP224. This paper is focused on two mapping technologies: CAD to Part111 mapping and Pat111 to AP224 mapping including case studios and it will provide the guideline about what should be done next in the AP203 Ed.2 to AP224 mapping. The final goal of this project is to integrate technical data from CAD to AP224 based manufacturing information through AP203 Ed.2.