• Title/Summary/Keyword: Primary Air

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Rapid Assessment of Ecosystem Services Apply to Local Stakeholders (지역 이해당사자 참여 생태계서비스 간이평가)

  • Kim, Byeo-Ri;Lee, Jae-Hyuck;Kim, Il-Kwon;Kim, Sung-Hoon;Kwon, Hyuk-Soo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.1
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    • pp.1-11
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    • 2019
  • This study suggested that various stakeholder can be participated in regional Environment planning and practical use of policy with rapid assessment of Ecosystem Services(ES). We applied to the rapid assessment of ES method to Ansan city and local registers selected Ecosystem assets that considered to space of ES. Ecosystem assets were measured 5 types Likert scale about 37 indicators of ES and confirm the main ES through the basic statistics. Furthermore Ecosystem assets classified according to similar character of ES. Ecosystem assets of Ansan were selected 47 site and Local climate regulation, Research and education, Primary production was high among the ES indicators. As a result two main group deduced that ecological education group(such as Research and education, Habitat) and safety regulation group(such as Air regulation, Fire regulation) through the factor analysis. In terms of location characteristics of each group, the ecological education-centered ecosystem assets were located near the downtown area, while the safety regulation group was located at the outskirts, such as mountains and coasts. This indicates that the ecological education about the habitat provision can be achieved in Ansan city downtown area and that outskirts should be approached from the aspect of ecological function to establish a plan. The result of Rapid assessment of ES, which can be lead a balanced and developmental consultation when establishing polices for environment planning and management in region.

Efficacy and Safety of Cheong-A-Won Gagambang (JCE003) on Knee Osteoarthritis: Randomized Controlled Pilot Trial

  • Kong, Haejin;Kang, Jaehui;Lee, Hyun
    • Journal of Acupuncture Research
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    • v.39 no.3
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    • pp.202-212
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    • 2022
  • Background: The aim of this study was to evaluate the effectiveness and safety of Cheong-A-Won Gagambang (JCE003) treatment for degenerative knee osteoarthritis. Methods: This was a single-center, randomized, double-blind, placebo-controlled pilot clinical trial. There were 36 adults with degenerative knee osteoarthritis who were randomly allocated into JCE003 1,000 mg, JCE003 2,000 mg, or the placebo group (in a 1:1:1 ratio). The participants received 12 weeks of treatment and had scheduled tests every 6 weeks. The primary outcomes were measured using the Korean Western Ontario and McMaster Universities scale, and the secondary outcomes were measured using the visual analog scale, European quality of life-5-dimensions, patient global impression of change, C-reactive protein, and erythrocyte sedimentation rate. Changes between baseline scores and scores following study completion were analyzed. Results: There were 29 participants whose data were analyzed in this study. The change of Korean Western Ontario and McMaster Universities, visual analog scale, European quality of life-5-dimensions scores showed significant improvement in the JCE003 1,000 mg group. The change of patient global impression of change was significantly improved in the placebo group. There were 14 adverse events, but there was no clinically significant relationship with the intake of JCE003 compared with the placebo. Conclusion: Taking JCE003 may be effective at improving knee pain in patients with degenerative knee osteoarthritis and appears to be safe. Based on this study, the concentration and feasibility of the test group may be used when conducting a large-scale clinical trial of degenerative knee osteoarthritis in the future.

Theoretical Heat Flow Analysis and Vibration Characteristics During Transportation of PCS(Power Conversion System) for Reliability (전력변환장치 캐비넷에서의 내부발열 개선을 위한 열유동 분석 및 유통안전성 향상을 위한 진동특성 분석)

  • Joo, Minjung;Suh, Sang Uk;Oh, Jae Young;Jung, Hyun-Mo;Park, Jong-Min
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.28 no.2
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    • pp.143-149
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    • 2022
  • PCS needs to freely switch AC and DC to connect the battery, external AC loads and renewable energy in both directions for energy efficiency. Whenever converting happens, power loss inevitably occurs. Minimization of the power loss to save electricity and convert it for usage is a very critical function in PCS. PCS plays an important role in the ESS(Energy Storage System) but the importance of stabilizing semiconductors on PCB(Printed Circuit Board) should be empathized with a risk of failure such as a fire explosion. In this study, the temperature variation inside PCS was reviewed by cooling fan on top of PCS, and the vibration characteristics of PCS were analyzed during truck transportation for reliability of the product. In most cases, a cooling fan is mounted to control the inner temperature at the upper part of the PCS and components generating the heat placed on the internal aluminum cooling plate to apply the primary cooling and the secondary cooling system with inlet fans for the external air. Results of CFD showed slightly lack of circulating capacity but simulated temperatures were durable for components. The resonance points of PCS were various due to the complexity of components. Although they were less than 40 Hz which mostly occurs breakage, it was analyzed that the vibration displacement in the resonance frequency band was very insufficient. As a result of random-vibration simulation, the lower part was analyzed as the stress-concentrated point but no breakage was shown. The steel sheet could be stable for now, but for long-term domestic transportation, structural coupling may occur due to accumulation of fatigue strength. After the test completed, output voltage of the product had lost so that extra packaging such as bubble wrap should be considered.

Radon Removal Efficiency of Activated Carbon Filter from Coconut (코코넛 기반 활성탄 필터의 라돈 제거 효율)

  • Yun-Jin Ahn;Gi-Sub Kim;Tae-Hwan Kim;Sang-Rok Kim
    • Journal of radiological science and technology
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    • v.46 no.2
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    • pp.141-149
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    • 2023
  • The Korea Institute of Radiological and Medical Sciences plans to produce 225Ac, a therapeutic radio-pharmaceutical for precision oncology, such as prostate cancer. Radon, a radioactive gas, is generated by radium, the target material for producing 225Ac. The radon concentration is expected to be about 2000 Bq·m-3. High-concentration radon-generating facilities must meet radioactive isotope emission standards by lowering the radon concentration. However, most existing studies concerning radon removal using activated carbon filters measured radon levels at concentrations lower than 1000 Bq·m-3. This study measured 222Rn removal of coconut-based activated carbon filter under a high radon concentration of about 2000 Bq·m-3. The 222Rn removal efficiency of activated carbon impregnated with triethylenediamine was also measured. As a result, the 222Rn removal amount of the activated carbon filter showed sufficient removal efficiency in a 222Rn concentration environment of about 2000 Bq·m-3. In addition, despite an expectation of low radon reduction efficiency of Triethylenediamine-impregnated activated carbon, it was difficult to confirm a significant difference in the results. Therefore, it is considered that activated carbon can be used as a radioisotope exhaust filter regardless of whether or not Triethylenediamine is impregnated. The results of this study are expected to be used as primary data when building an air purification system for radiation safety management in facilities with radon concentrations of about 2000 Bq·m-3.

A Spatial Analysis of Transit Centers in Seoul Metropolitan Region for Developing Transit Oriented Urban Environments (대중교통중심형 도시로의 개편을 위한 역세권 도시공간구조 분석)

  • Park, Se-Hoon;Sohn, Dong-Wook;Lee, Jin-Hee
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.1D
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    • pp.111-120
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    • 2009
  • Restructuring urban land use patterns from the motor-oriented to transit-oriented ones is a contemporary trend in urban planning and transportation. It is expected that transforming urban land use patterns to be transit and walking friendly would resolve various urban problems such as heavy energy consumptions, air pollutions, and traffic congestions. Korean cities have much potentials for developing transit-oriented urban environments in terms of its density and civil service levels, but the level of transit usage levels and the environmental quality of cities are not good enough for supporting such transition. The purpose of this study is to analyze the urban transit center areas and identify the problems to be solved to create transit-oriented urban environments. Case studies of four urban transit center areas in Seoul Metropolitan region were conducted to examine the spatial characteristics of urban transit center areas and identify their problems. Development density, land use diversity, walk-ability and transit connectivity were the primary feature of interests.

Developing a BIM-Based Methodology Framework for Sustainability Analysis of Low Carbon High-Rise Buildings

  • Gan, Vincent J.L.;Li, Nan;Tse, K.T.;Chan, C.M.;Lo, Irene M.C.;Cheng, Jack C.P.
    • International conference on construction engineering and project management
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    • 2017.10a
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    • pp.14-23
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    • 2017
  • In high-density high-rise cities such as Hong Kong, buildings account for nearly 90% of energy consumption and 61% of carbon emissions. Therefore, it is important to study the design of buildings, especially high-rise buildings, to achieve lower carbon emissions in the city. The carbon emissions of a building consist of embodied carbon from the production of construction materials and operational carbon from energy consumption during daily operation (e.g., air-conditioning and lighting). An integrated analysis of both types of carbon emissions can strengthen the design of low carbon buildings, but most of the previous studies concentrated mainly on either embodied or operational carbon. Therefore, the primary objective of this study is to develop a holistic methodology framework considering both embodied and operational carbon, in order to enhance the sustainable design of low carbon high-rise buildings. The framework will be based on the building information modeling (BIM) technology because BIM can be integrated with simulation systems and digital models of different disciplines, thereby enabling a holistic design and assessment of low carbon buildings. Structural analysis program is first coupled with BIM to validate the structural performance of a building design. The amounts of construction materials and embodied carbon are then quantified by a BIM-based program using the Dynamo programming interface. Operational carbon is quantified by energy simulation software based on the green building extensible Markup Language (gbXML) file from BIM. Computational fluid dynamics (CFD) will be applied to analyze the ambient wind effect on indoor temperature and operational carbon. The BIM-based framework serves as a decision support tool to compare and explore more environmentally-sustainable design options to help reduce the carbon emissions in buildings.

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A study on improving the IUU Fishing Index of Korea's distant water fisheries (한국의 원양어업 IUU어업지수 개선방안 연구)

  • Zang Geun KIM;Youjung KWON;Haewon LEE;Doo Nam KIM;Jaebong LEE
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.4
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    • pp.362-376
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    • 2023
  • The IUU Fishing Index is composed of 40 indicators. These indicators were grouped by state responsibilities (flag, coastal, port, and general including market) defined in the FAO IPOA-IUU (2001) and then by type into vulnerability, prevalence, and response. A total of 152 coastal nations was surveyed. Korea's total combined IUU Fishing Index was 2.49 in 2019 and 2.91 in 2021, indicating a drop in the ranking to the third worst out of 152 countries followed by China and Russia in 2021. The indicators that increased the IUU fishing risk in 2021 compared to 2019 included seven indicators of prevalence and two indicators of response while those reducing the risk included one prevalence and one response indicator. The IUU Fishing Index revealed that many fisheries observers and monitoring, control and surveillance (MCS) practitioners active in the waters of RFMOs jurisdiction where Korean distant water vessels operate have mentioned concerns about the compliance with RFMO conservation measures or fishing practices. It suggested that strengthening management intervention in the fishing sector is needed. The primary tool for management is the MCS system. Given the logistical difficulty of oversight from land, air and at-sea, there is a need to enhance MCS strategies through logbook data, at-sea observer and electronic monitoring program. It also suggested that MSC fisheries certification and fisheries improvement projects, which are widely used for improving fishing sector performance, could contribute to the eradication of IUU fishing and the promotion of sustainable distant water fisheries.

Main causes of missing errors during software testing

  • Young-Mi Kim;Myung-Hwan Park
    • Journal of the Korea Society of Computer and Information
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    • v.29 no.6
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    • pp.89-100
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    • 2024
  • The primary goal of software testing is to identify and correct errors within software. A key challenge in this process is error masking, where errors disappear internally before reaching the output. This paper investigates the causes and characteristics of error masking, which complicates software testing. The study involved injecting artificial errors into three software programs to examine the extent of error masking by various test cases and to explore the underlying reasons. The experiment yielded four major findings. First, about 50% of the error masking occurred because the errors were not executed. Second, among various operators, logical and arithmetic operators masked errors less frequently, while relational and temporal operators tended to mask errors more extensively. Third, certain test cases demonstrated exceptional effectiveness in propagating errors to the output. Fourth, the type of error injected influenced the masking effect.

Public Electric Car Charging Locations Based on Car Navigation Data in Seoul (네비게이션 데이터를 바탕으로 한 서울시의 공공 전기차 충전소 위치)

  • Taekyung Kim;Jangyoung Kim;Yoon Gi Yang
    • Information Systems Review
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    • v.18 no.4
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    • pp.1-15
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    • 2016
  • Electric cars are expected to increase quality of life by reducing air pollution and to contribute to economic growth by creating new businesses. However, electric car adoption has lagged and has not satisfied public expectation. One of the primary reasons for this outcome is the slow charging speed or inconvenience of charging a battery. Under the insufficient diffusion of electric cars, pushing business entities to construct charging facilities is undesirable for a policy maker to increase the adoption rate because of cost and management issues. This study adopts the design science methodology to interpret the problem of deploying electric car charging stations in the view of information systems. A trip planning algorithm is suggested on the basis of the theory of range anxiety. We investigate issues related to the current charging locations using data from drivers' car navigation devices. We also review its applicability to trip planning to obtain insights.

Assessment of Occupational Health Risks for Maintenance Work in Fabrication Facilities: Brief Review and Recommendations

  • Dong-Uk Park;Kyung Ehi Zoh;Eun Kyo Jeong;Dong-Hee Koh;Kyong-Hui Lee;Naroo Lee;Kwonchul Ha
    • Safety and Health at Work
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    • v.15 no.1
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    • pp.87-95
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    • 2024
  • Background: This study focuses on assessing occupational risk for the health hazards encountered during maintenance works (MW) in semiconductor fabrication (FAB) facilities. Objectives: The objectives of this study include: 1) identifying the primary health hazards during MW in semiconductor FAB facilities; 2) reviewing the methods used in evaluating the likelihood and severity of health hazards through occupational health risk assessment (OHRA); and 3) suggesting variables for the categorization of likelihood of exposures to health hazards and the severity of health effects associated with MW in FAB facilities. Methods: A literature review was undertaken on OHRA methodology and health hazards resulting from MW in FAB facilities. Based on this review, approaches for categorizing the exposure to health hazards and the severity of health effects related to MW were recommended. Results: Maintenance workers in FAB facilities face exposure to hazards such as debris, machinery entanglement, and airborne particles laden with various chemical components. The level of engineering and administrative control measures is suggested to assess the likelihood of simultaneous chemical and dust exposure. Qualitative key factors for mixed exposure estimation during MW include the presence of safe operational protocols, the use of air-jet machines, the presence and effectiveness of local exhaust ventilation system, chamber post-purge and cooling, and proper respirator use. Using the risk (R) and hazard (H) codes of the Globally Harmonized System alongside carcinogenic, mutagenic, or reprotoxic classifications aid in categorizing health effect severity for OHRA. Conclusion: Further research is needed to apply our proposed variables in OHRA for MW in FAB facilities and subsequently validate the findings.