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Policy Direction for Fire Products Life Expectancy Legislation (소방용품 내용연수 제도화 정책방안)

  • Baek, Chang Sun;Park, In-Seon
    • Fire Science and Engineering
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    • v.30 no.1
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    • pp.111-120
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    • 2016
  • This study is intended to provide legislative direction for fire products life expectancy. Domestic and international laws relating to fire products life expectancy have been reviewed, and the results of a Fire Safety Manager Consciousness (FSMC) survey were analyzed. The FSMC survey has been designed in order to assist with the establishment of appropriate fire safety policy. A questionnaire survey was conducted with 660 fire safety administrators from 17 municipal and provincial districts, with the intention of gaining expertise on the extension of life-span for 32 fire products. The survey also asked for candidates opinions on future policy direction. Based on the survey results and the review of policies within other nations, we have devised a set of policy issues with the intention of extending the life-span of fire-safety items. The survey result revealed that 79.3% of Fire Safety Managers (FSMs) concurred with the establishment of legislation regarding the maintenance and correct care of fire-safety products. Overall, over 30% of FSMs were in favor of regulations regarding Ddry chemical fire extinguishers (77.3%), fire detectors (44.6%), fire hoses (44.4%), gaseous agent fire extinguisher (40.6%), automatic descending life lines (36.2%), exit lights (35.9%), air respirators (35.9%), extinguishing systems for residential cooking facilities (33.9%), automatic spray-type extinguishing units (33.9%), emergency lights (31.2%), and gas leakage detectors (30.7%). Especially, among these, dry chemical fire extinguishers (60.0%), detectors (20.0%), and fire hose (18.8%) were identified as the fire products primarily in need of maintenance legislation. The general consensus is that fire products older than 10 years need to be replaced. Based on the survey results, there was general agreement that fire product life expectancy is in need of legislation. This study recommends the introduction of fire product life expectancy legislation in phases.

Analysis of Air Circulation in Oyster Mushroom Farm

  • Jeong, Won-Geun;Lim, Hack-Kyu;Kim, Tae-Han
    • Journal of Biosystems Engineering
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    • v.37 no.2
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    • pp.75-81
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    • 2012
  • Oyster mushroom farm which could not meet optimum temperature range yields non-uniform sized, low quality products. Thus, this study, utilizing STAR CCM+, one of the computational fluid dynamics (CFD) programs, analyzed the impact of air circulation and temperature distribution. Methods: After we visited numerous mushroom farms, we measured the temperature at the discharge ports of heaters, fan capacity, and the locations of the air circulators in the farms. According to the data, most mushroom growers installed the heaters near the entrance and discharge ports of the heaters at the third growing bed on the same height as the heaters in the entrance. The temperature at the discharge port of heater was $1,26^{\circ}C$, and the fan capacity was 4,500 $m^3$/hr. The air circulator was placed in the center of the mushroom farm 50cm above the ground, and its capacity of inlet port was 1,100 $m^3$/hr and discharge port 1,600 $m^3$/hr. The mushroom farm was insulated. Results: According to the analysis of the temperature distribution in the vertical plane of the entrance side, no air circulation causes the high temperature zone of 296~299K at the discharge port of the heater to take up 34% of area while the operation of air circulators causes it to occupy only 9%. This means that not using air circulators leads to a concentration of high temperature at the discharge port near the entrance. In addition, with the results of the analysis of the temperature distribution in the vertical planes of the center, no air circulation causes the temperature zone of 295~298K at the discharge port of the heater to take up 48% of area while the operation of air circulators causes it to occupy 80%. This shows that the high outlet port temperature disseminated to the center. Conclusions: After ninety minute operation of both heater and air circulator, the interior temperature became stabilized in the mushroom farm. Air circulation made the high temperature at the discharge port disseminate to the center and exit in the farm and equalize the temperature distribution.

The emission of VOCs as landfill gas (LFG) from an urban landfill site (도심지역 매립장의 VOC 성분 조성과 배출 특성에 대한 연구)

  • Kim, Ki-Hyun;Choi, Gyoo-Hoon;Oh, Sang-In;Choi, Ye-Jin;Sun, Wooyoung;Jeon, Ui-Chan;Ju, Do Weon
    • Analytical Science and Technology
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    • v.16 no.5
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    • pp.407-417
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    • 2003
  • In this study, we measured the concentration of VOCs in ambient air and landfill gas (LFG) in a midsize municipal landfill site. The LFG flux values of VOCs were computed using a total of fifteen VOCs determined by GC-PID system. To understand relative contribution of these 15 VOCs to the total carbon budget, their concentration and flux estimates were compared to those of non-methane hydrocarbons (NMHC) measured concurrently. It was also found that there were systematic differences in absolute VOC concentration levels between LFG and air samples above landfill surface. The VOC concentrations in LFG samples were high enough to reach above a few tens of ppm that are 10 to 100 times higher than those in air above landfill surface. If the LFG flux values were computed using the LFG concentration data of 15 VOCs and NMHC with exit ventilation speed, the magnitude of emissions in the study area is estimated to be 8.6 and 103 ton C/yr, respectively. In the meantime, large fraction of those speciated VOC emissions is accounted for by BTEX.

The New International Division of Labor:Re-evaluation (신국제노동분업의 재평가)

  • 고태경
    • Journal of the Korean Regional Science Association
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    • v.11 no.1
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    • pp.79-91
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    • 1995
  • As an exit to solve the economic depression of the development countries in the early twentieth century, the 'old international division of labor' developed. The economic crisis(i.e., under-consumption crisis) was due to the absence of the mode of regulation compatible with the extensive regime of accumulation(i.e., "Fordist" regime). The crisis was solved by the state intervention through the creation on institutions in order to increase the level of consumption. Until the late 1960s when "high Fordism" reached(i.e., a harmonious relation between the monopoly mode of regulation and the intensive accumulation of capital), the developed core countries enjoyed a remarkable economic growth. The external market was not a necessity for the economic growth because there were increases in labor productivity and proportional increases in real wages and thus increases in consumption level. In the 1970s, however, the core faced with economic crisis again. Due to the breakdown of the postwar "Fordist" regime of capital accumulation and the post 1973 world depression, the core needed the Third World as a solution for their internal and international economic crisis. Thus the 'new international division of labor'(NIDL) arose. The "Fordist" method of production(i.e., the divisions of production process) led to the territorial division of labor and to the detailed division of labor. The aim of the NIDL is to exploit reserve armies of labor on a world scale and thus to reduce production costs. According to the NIDL model, the Third World countries have been developing by the core countries' investment on mainly labor-intensive industries and thus have been playing an important role in the global economy. And the NIDL theorists argue that multinational corporations have increasingly invested in the Third World nations and contributed to the economic growth in those regions. Tables presented in the paper show that the global trend since the 1970s does not follow the argument exactly as the NIDL theorists predicted. On the contrary, the core countries focus on developing technology, adopting the automation of production process, and trading within the core countries rather than on investing in the periopheral countries. The continuing investment of multinational corporations into the periphery is not because of cheap labor force but because of the market potentials in the regions. Majority of corporations of the core tries to reduce production costs by investing in technological development more intensively and also by changing regional strategies (i.E., investment from metropolitan areas to medium - or small - size cities, focusing on agglomeration economy, boosting regional diversification, etc.) within their own countries. The main purpose of the paper is to review and to criticize the NIDL theory based on some empirical data.IDL theory based on some empirical data.

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Study on the Safety Analysis on the Cooling Performance of Hybrid SIT under the Station Blackout Accident (발전소 정전사고 시 Hybrid SIT의 냉각성능 평가를 위한 안전해석에 관한 연구)

  • Ryu, Sung Uk;Kim, Jae Min;Kim, Myoung Joon;Jeon, Woo Jin;Park, Hyun-Sik;Yi, Sung-Jae
    • Journal of Energy Engineering
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    • v.26 no.3
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    • pp.64-70
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    • 2017
  • The concept of Hybrid Safety Injection Tank (Hybrid SIT) proposed by the Korea Atomic Energy Research Institute (KAERI) has been introduced for the purpose of application to the Advanced Power Reactor Plus (APR+). In this study, the SBO situation of the APR+ was analyzed by using the MARS-KS code in order to evaluate whether the operation of the Hybrid SIT has an effect on the cooling performance of the Reactor Coolant System (RCS). According to the analysis, when the actuation valve on the pressure balancing line (PBL) is opened, the Hybrid SIT's pressure rises rapidly, forming equilibrium with the RCS pressure; subsequently, a flow is injected from the Hybrid SIT into the reactor vessel through the direct vessel injection (DVI) line. The analysis showed that it is possible to keep the core temperature below melting temperature during the operation of a Hybrid SIT.

Conception Types of Elementary School Students about the Moon Phase Changes and the Suggestions and Effects of Teaching Methods (초등학생들의 달의 위상변화에 대한 개념 유형과 수업 방법의 제안 및 효과)

  • Son, Jun Ho
    • Journal of The Korean Association For Science Education
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    • v.35 no.2
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    • pp.289-301
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    • 2015
  • This study noted that elementary school students were unable to accurately comprehend the principles of moon phase changes and that teachers themselves lacked a full understanding of it as well. Therefore, this study classifies conception types through 161 5th grade respondents and suggests how to change students' conception types through the use of reconstructed teaching and learning materials (that have been developed in existing studies). It verified the changes in the learning achievement of 129 5th grade respondents and analyzed how to think about reconstructed teaching and learning materials through four teacher respondents and four 5th grade respondents from the same study. The results of this study are as follows: First, the conception types on moon phase changes were classified into C and W types. W types consisted of W1, W2, W3, W4, and W5 types. Students had difficulty in understanding the principles of a waxing crescent moon and first quarter phase changes. Second, the group taking classes, which implemented reconstructed teaching and learning materials, showed greater improvement in learning achievement posttest and long-term tests compared to those who have not. Finally, teachers and students reacted positively to the reconstructed teaching and learning materials as shown in exit survey results. In conclusion, it is suggested that teachers are better off utilizing reconstructed teaching and learning materials so that elementary school students may fully understand the principles of moon phase changes rather than just memorizing the results.

Operating Characteristics of a Continuous Two-Stage Bubbling Fluidized-Bed Process (연속식 2단 기포 유동층 공정의 운전특성)

  • Youn, Pil-Sang;Choi, Jeong-Hoo
    • Korean Chemical Engineering Research
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    • v.52 no.1
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    • pp.81-87
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    • 2014
  • Flow characteristics and the operating range of gas velocity was investigated for a two-stage bubbling fluidized-bed (0.1 m-i.d., 1.2 m-high) that had continuous solids feed and discharge. Solids were fed in to the upper fluidized-bed and overflowed into the bed section of the lower fluidized-bed through a standpipe (0.025 m-i.d.). The standpipe was simply a dense solids bed with no mechanical or non-mechanical valves. The solids overflowed the lower bed for discharge. The fluidizing gas was fed to the lower fluidized-bed and the exit gas was also used to fluidize the upper bed. Air was used as fluidizing gas and mixture of coarse (< $1000{\mu}m$ in diameter and $3090kg/m^3$ in apparent density) and fine (< $100{\mu}m$ in diameter and $4400kg/m^3$ in apparent density) particles were used as bed materials. The proportion of fine particles was employed as the experimental variable. The gas velocity of the lower fluidized-bed was defined as collapse velocity in the condition that the standpipe was emptied by upflow gas bypassing from the lower fluidized-bed. It could be used as the maximum operating velocity of the present process. The collapse velocity decreased after an initial increase as the proportion of fine particles increased. The maximum took place at the proportion of fine particles 30%. The trend of the collapse velocity was similar with that of standpipe pressure drop. The collapse velocity was expressed as a function of bulk density of particles and voidage of static bed. It increased with an increase of bulk density, however, decreased with an increase of voidage of static bed.

Effects of Knowledge-based Startups on Employment Growth (지식기반산업 창업기업의 고용창출 효과)

  • Lee, Jeong Hyun;Lee, Hee Yeon
    • Journal of the Economic Geographical Society of Korea
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    • v.20 no.2
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    • pp.137-157
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    • 2017
  • As unemployment rises and economic growth slows, interest in startups, which is considered to be the driving force of job creation, is increasing. This study aimed to analyze the employment effects of knowledge-based startups in South Korea. In particular, startups were divided into three categories (knowledge-based manufacturing, knowledge-based service, and other industries) and the region were divided into the capital region and the other regions. The result of the analysis, which used census on Establishments Data from Statistics Korea(KOSIS), showed that the employment effects of startups change in three steps over time. When new firms were created, employment increases instantly. However, as the competition among firms increases, some firms exit the market and employment decreases. In the long-term, some firms will survive the market competition and increase their firm size and the number of jobs they offer. The total employment effect was greater for knowledge-based startups than the other industries startups. The total employment effect of knowledge-based startups are 2.84%p for the period of 6 years. Startups in the Capital region showed higher employment effect than startups in other regions. This implies that in the capital region, employment increases more after the startups are created, but due to fierce competition, employment also decreases relatively more than it does in other regions. However, companies that survive competition create more employment. This study may give some policy implications that startup policies should be tailored to the startup's type and regional characteristics in order to achieve more effective job creation performance.

A Study on the Determinant Factor Analysis for the Characterization of Saemangeum New Port (새만금신항만 특화에 관한 결정요인 분석에 관한 연구)

  • Kim, Nam-Suk;Choe, Do-Won;Jeon, Young-Hwan
    • Journal of Korea Port Economic Association
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    • v.28 no.1
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    • pp.263-288
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    • 2012
  • This study aims to define which factors will contribute to vitalization of Saemangeum New Port to secure international competitiveness in order to attract international shipping companies, shippers and forwarders in constructing Saemangeum New Port, and to propose subsequent implications. For research methods of the current study, a factor analysis and a decision making method of analytic hierarchy process(AHP) were used. Through precedent studies, total 11 measuring variables were selected including short entrance and exit channels, main infrastructure development project, tax cut and deregulation, and through a factor analysis, total 3 high rank evaluation factors including 'location and facilities', 'surrounding infrastructure and hydrophile property', and 'local policy and environment'. Analysis results summarizing a test of reliability of measuring variables in this study indicate that as Cronbach alpha coefficient of total 11 measuring variables were turned out to be over 0.8, it is surpassing general average 0.6, which means there is reliability.

A Study on the Conditions Analysis and Assessment of Supporting Port for Offshore Wind Farm : Focusing on Ports in Gyeongsangnam-do (해상풍력단지 지원항만 여건 분석 및 평가에 관한 연구 -경상남도 항만을 중심으로-)

  • Yang, Hang-Jin;Chiang, Bong-Gyu
    • Journal of Korea Port Economic Association
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    • v.35 no.4
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    • pp.85-106
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    • 2019
  • Offshore wind power is a representative renewable energy source and a rapidly growing industry. In Gyeongsangnam-do, offshore wind farms of 461.9MW are being pushed for in the Yokji island and are expected to expand further to over 1GW in the future. Accordingly, ports supporting the storage, assembly, transportation, and installation of offshore wind power equipment are expected to play an important role in the smooth progress of the offshore wind farm development project. Based on previous research and cases in major countries,this study prepared criteria for assessment of ports supporting offshore wind farmsand evaluated ports in Gyeongsangnam-do, which are linked to Yokji island offshore wind farms. The assessment criteria have been subdivided into distance from the offshore wind farm, port entry and exit restrictions, navigational areas, fishery rights factors, additional costs, berth length, depth of berth, size of the port yard, port berth bearing pressure, interference with other cargo, a civil appeal, and relevant industrial aggregation. The ports of Tongyeong, Samcheonpo, Kohyun, Masan, and Jinhae in Gyeongsangnam-do were selected and evaluated. As a result, the port of Tongyoung was superior in terms of distance from the Yokji island offshore wind farm. The ports of Samcheonpo, Masan, and Jinhae were evaluated as excellent in other criteria such as berth length, depth of berth, and so on. This study is expected to be used as a source of basic data for offshore wind power companies and policymakers to select and evaluate the supporting ports of offshore wind farms.