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Monitoring of Working Environment Exposed to Particulate Matter in Greenhouse for Cultivating Flower and Fruit (과수 및 화훼 시설하우스 내 작업자의 미세먼지 노출현황 모니터링)

  • Seo, Hyo-Jae;Kim, Hyo-Cher;Seo, Il-Hwan
    • Journal of Bio-Environment Control
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    • v.31 no.2
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    • pp.79-89
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    • 2022
  • With the wide use of greenhouses, the working hours have been increasing inside the greenhouse for workers. In the closed ventilated greenhouse, the internal environment has less affected to external weather during making a suitable temperature for crop growth. Greenhouse workers are exposed to organic dust including soil dust, pollen, pesticide residues, microorganisms during tillage process, soil grading, fertilizing, and harvesting operations. Therefore, the health status and working environment exposed to workers should be considered inside the greenhouse. It is necessary to secure basic data on particulate matter (PM) concentrations in order to set up dust reduction and health safety plans. To understand the PM concentration of working environment in greenhouse, the PM concnentrations were monitored in the cut-rose and Hallabong greenhouses in terms of PM size, working type, and working period. Compare to no-work (move) period, a significant increase in PM concentration was found during tillage operation in Hallabong greenhouse by 4.94 times on TSP (total suspended particle), 2.71 times on PM-10 (particle size of 10 ㎛ or larger), and 1.53 times on PM-2.5, respectively. During pruning operation in cut-rose greenhouse, TSP concentration was 7.4 times higher and PM-10 concentration was 3.2 times higher than during no-work period. As a result of analysis of PM contribution ratio by particle sizes, it was shown that PM-10 constitute the largest percentage. There was a significant difference in the PM concentration between work and no-work periods, and the concentration of PM during work was significant higher (p < 0.001). It was found that workers were generally exposed to a high level of dust concentration from 2.5 ㎛ to 35.15 ㎛ during tillage operation.

A Study on Calculation of Air Pollutant Emissions from ships at Incheon Port and the Effects of Eco-Friendly Policies (인천항 선박 대기오염물질 배출량 산정 및 친환경 정책 효과에 대한 연구)

  • Lee, Jungwook;Lee, Hyangsook
    • Journal of Korea Port Economic Association
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    • v.38 no.1
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    • pp.129-142
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    • 2022
  • In the past, interest in air pollution was concentrated on greenhouse gases, but in recent years, interest in fine dust has been increasing. The media and environmental organizations continue to emphasize air pollution caused by fine dust. The awareness of fine dust is increasing, and air pollution generated at ports is analyzed to be serious as a domestic factor excluding foreign inflows. Recognizing this, in order to reduce air pollution generated at ports, special laws on improving air quality, such as port areas, have been enacted in Korea, and attempts are being made to curb air pollution caused by ports. In this law, it is a policy that regulates air pollutants generated not only by ships but also throughout ports such as vehicles and unloading machines, and representative are ECA, VSR, and AMP. This study attempted to analyze the effects of these eco-friendly policies at Incheon Port. First of all, a study was conducted to calculate emissions assuming that there was no policy, analyze each policy, and finally calculate and compare actual emissions reflecting all policies. The methodology presented by the European Environmental Administration and the U.S. Environmental Protection Agency was used, and pollutants to be analyzed were analyzed for sulfur oxides (SOX), carbon monoxide (CO), nitrogen oxides (NOX), total floating substances (TSP), fine dust and ultrafine dust (PM10, PM2.5) and ammonia (NH3). As a result of the analysis, it was analyzed that the actual emission reflecting all policies was about 4,097 tons/year, which had an emission reduction effect of about 760 tons/year compared to about 4,857 tons/year when the policy was not reflected. When the effects of each policy were analyzed individually, it was found that ECA 4,111 tons/year, VSR 4,854 tons/year, and AMP 4,843 tons of air pollutant emissions occurred The results of this study can be used as basic data and evidence for policy establishment related to the atmospheric environment at Incheon Port.

Development of the Filterable Water Sampler System for eDNA Filtering and Performance Evaluation of the System through eDNA Monitoring at Catchment Conduit Intake-Reservoir (eDNA 포집용 채수 필터시스템 개발과 집수매거 취수지 내에서의 성능평가)

  • Kwak, Tae-Soo;Kim, Won-Seok;Lee, Sun Ho;Kwak, Ihn-Sil
    • Korean Journal of Ecology and Environment
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    • v.54 no.4
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    • pp.272-279
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    • 2021
  • A pump-type eDNA filtering system that can control voltage and hydraulic pressure respectively has been developed, and applied a filter case that can filter out without damaging the filter. The filtering performance of the developed system was evaluated by comparing the eDNA concentration with the conventional vacuum-pressured filtering method at the catchment conduit intake reservoir. The developed system was divided into a voltage control (manual pump system) method and a pressure control (automatic pump system) method, and the pressure was measured during filtering and the pressure change of each system was compared. The voltage control method started with 65 [KPa] at the beginning of the filtering, and as the filtering time elapsed, the amount of filtrate accumulated in the filter increased, so the pressure gradually increased. As a result of controlling the pressure control method to maintain a constant pressure according to the designed algorithm, there was a difference in the width of the hydraulic pressure fluctuation during the filtering process according to the feedback time of the hydraulic pressure sensor, and it was confirmed that the pressure was converged to the target pressure. The filtering performance of the developed system was confirmed by measuring the eDNA concentration and comparing the voltage control method and the hydraulic control method with the control group. The voltage control method obtained similar results to the control group, but the hydraulic control method showed lower results than the control group. It is considered that the low eDNA concentration in the hydraulic control method is due to the large pressure deviation during filtering and maintaining a constant pressure during the filtering process. Therefore, rather than maintaining a constant pressure during filtering, it was confirmed that a voltage control method in which the pressure is gradually increased as the filtrate increases with the lapse of filtering time is suitable for collecting eDNA. As a result of comparing the average concentration of eDNA in lentic zone and lotic zone as a control group, it was found to be 96.2 [ng µL-1] and 88.4 [ng µL-1l], respectively. The result of comparing the average concentration of eDNA by the pump method was also high in the lentic zone sample as 90.7 [ng µL-1] and 74.8 [ng µL-1] in the lentic zone and the lotic zone, respectively. The high eDNA concentration in the lentic zone is thought to be due to the influence of microorganisms including the remaining eDNA.

A Study on Changes in the Safety Perception of Port Workers in accordance with the Enforcement of the Serious Disasters Act (중대재해법 시행에 따른 항만노동자의 안전인식 변화)

  • Park, Junkyu;Park, Keun-Sik
    • Journal of Korea Port Economic Association
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    • v.38 no.3
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    • pp.133-149
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    • 2022
  • The Port logistics is a pivotal industry in strengthening competitiveness for countries and companies and plays an important role in accounting for the majority of Korea's import and export volume, so its importance among Korea's industries is truly enormous. The port, which plays such an important role, is simultaneously unloaded, transferred into the dock, and stored, and it can be said that it is composed of a very complex flow. In particular, port unloading is an environment in which port unloading workers cannot escape the risk of disasters as large cargoes and cranes for container transport move, and numerous disasters are hidden and lead to serious disasters. Through literature studies on the Serious Accident Penalty Act, this study investigated how the Serious Accident Penalty Act affected port unloading workers and whether there was a change in satisfaction with safety education according to the enforcement of the Serious Accident Penalty Act. Through this study, it was found that port unloading workers were more aware of safety than managers in cognitive, attitude, and experience factors. Since the port unloading manager is not put into the unloading work, the perception of safety was analyzed to be lower than that of workers. Since managers should educate workers on safe work and be alert to safety, it seems that port unloading managers will also need to change their perception of safety. The Act on the Punishment of Severe Disasters took effect on January 27, 22, and in the early stages of the enforcement of the law, many confusing and ambiguous parts are found for those in charge of performing practical tasks on the front line until the law is settled. It seems necessary to revise the Act on the Punishment of Severe Disasters for the purpose of clear standards for the law and no safety accidents in the field to prevent confusion in work. In addition, in order to derive more meaningful research results in the future, it is expected that research on the perception of disasters by workers and managers will be continuously needed by deepening literature research to find various factors and using investigation methods such as interviews.

Origin and Reservoir Types of Abiotic Native Hydrogen in Continental Lithosphere (대륙 암석권에서 무기 자연 수소의 성인과 부존 형태)

  • Kim, Hyeong Soo
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.3
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    • pp.313-331
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    • 2022
  • Natural or native abiotic molecular hydrogen (H2) is a major component in natural gas, however yet its importance in the global energy sector's usage as clean and renewable energy is underestimated. Here we review the occurrence and geological settings of native hydrogen to demonstrate the much widesprease H2 occurrence in nature by comparison with previous estimations. Three main types of source rocks have been identified: (1) ultramafic rocks; (2) cratons comprising iron (Fe2+)-rich rocks; and (3) uranium-rich rocks. The rocks are closely associated with Precambrian crystalline basement and serpentinized ultramafic rocks from ophiolite and peridotite either at mid-ocean ridges or within continental margin(Zgonnik, 2020). Inorganic geological processes producing H2 in the source rocks include (a) the reduction of water during the oxidation of Fe2+ in minerals (e.g., olivine), (b) water splitting due to radioactive decay, (c) degassing of magma at low pressure, and (d) the reaction of water with surface radicals during mechanical breaking (e.g., fault) of silicate rocks. Native hydrogen are found as a free gas (51%), fluid inclusions in various rock types (29%), and dissolved gas in underground water (20%) (Zgonnik, 2020). Although research on H2 has not yet been carried out in Korea, the potential H2 reservoirs in the Gyeongsang Basin are highly probable based on geological and geochemical characteristics including occurrence of ultramafic rocks, inter-bedded basaltic layers and iron-copper deposits within thick sedimentary basin and igneous activities at an active continental margin during the Permian-Paleogene. The native hydrogen is expected to be clean and renewable energy source in the near future. Therefore it is clear that the origin and exploration of the native hydrogen, not yet been revealed by an integrated studies of rock-fluid interaction studies, are a field of special interest, regardless of the presence of economic native hydrogen reservoirs in Korea.

A Checklist to Improve the Fairness in AI Financial Service: Focused on the AI-based Credit Scoring Service (인공지능 기반 금융서비스의 공정성 확보를 위한 체크리스트 제안: 인공지능 기반 개인신용평가를 중심으로)

  • Kim, HaYeong;Heo, JeongYun;Kwon, Hochang
    • Journal of Intelligence and Information Systems
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    • v.28 no.3
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    • pp.259-278
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    • 2022
  • With the spread of Artificial Intelligence (AI), various AI-based services are expanding in the financial sector such as service recommendation, automated customer response, fraud detection system(FDS), credit scoring services, etc. At the same time, problems related to reliability and unexpected social controversy are also occurring due to the nature of data-based machine learning. The need Based on this background, this study aimed to contribute to improving trust in AI-based financial services by proposing a checklist to secure fairness in AI-based credit scoring services which directly affects consumers' financial life. Among the key elements of trustworthy AI like transparency, safety, accountability, and fairness, fairness was selected as the subject of the study so that everyone could enjoy the benefits of automated algorithms from the perspective of inclusive finance without social discrimination. We divided the entire fairness related operation process into three areas like data, algorithms, and user areas through literature research. For each area, we constructed four detailed considerations for evaluation resulting in 12 checklists. The relative importance and priority of the categories were evaluated through the analytic hierarchy process (AHP). We use three different groups: financial field workers, artificial intelligence field workers, and general users which represent entire financial stakeholders. According to the importance of each stakeholder, three groups were classified and analyzed, and from a practical perspective, specific checks such as feasibility verification for using learning data and non-financial information and monitoring new inflow data were identified. Moreover, financial consumers in general were found to be highly considerate of the accuracy of result analysis and bias checks. We expect this result could contribute to the design and operation of fair AI-based financial services.

Development of Potassium Impregnated Carbon Absorbents for Indoor CO2 Adsorption (K계열 함침 탄소계 흡착제의 실내 저농도 이산화탄소 흡착성능 강화)

  • Jeong, Se-Eun;Wang, Shuang;Lee, Yu-Ri;Won, Yooseob;Kim, Jae-Young;Jang, Jae Jun;Kim, Hana;Jo, Sung-ho;Park, Young Cheol;Nam, Hyungseok
    • Korean Chemical Engineering Research
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    • v.60 no.4
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    • pp.606-612
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    • 2022
  • Relatively high indoor CO2 concentration (>1,000 ppm) has a negative impact on human health. In this work, indoor CO2 adsorbent was developed by impregnating KOH or K2CO3 on commercial activated carbon, named as KOH/AC and K2CO3/AC. Commercial activated carbon (AC) showed relatively high BET surface area (929 m2/g) whereas KOH/AC and K2CO3/AC presented lower BET surface area of 13.6 m2/g and 289 m2/g. Two experimental methods of TGA (2,000 ppmCO2, weight basis) and chamber test (initial concentration: 2,000 ppmCO2, CO2 IR analyzer) were used to investigate the adsorption capacity. KOH/AC and K2CO3/AC exhibited similar adsorption capacities (145~150 mgCO2/g), higher than K2CO3/Al+Si supports adsorbent (84.1 mgCO2/gsample). Similarly, chamber test also showed similar trend. Both KOH/AC and K2CO3/AC represented higher adsorption capacities (KOH/AC: 93.5 mgCO2/g K2CO3/AC: 94.5 mgCO2/gsample) K2CO3/Al+Si supports. This is due to the KOH or K2CO3 impregnation increased alkaline active sites (chemical adsorption), which is beneficial for CO2 adsorption. In addition, the regeneration test results showed both K-based adsorbents pose a good regeneration and reusability. Finally, the current study suggested that both KOH/AC and K2CO3/AC have a great potential to be used as CO2 adsorbent for indoor CO2 adsorption.

Applying the Theory of Affordance to the Design of Water Purification Facilities : Focusing on the Case of Binh Dinh in Vietnam (정수시설 설계에 대한 어포던스 이론 적용 연구: 베트남 빈딘 사례를 중심으로)

  • Park, Hye-Rin;Hwang, Yeo-Kyeong;Kim, Seul-Gi;Lee, Jun-Min;Hwang, Jun-Seok
    • Journal of Appropriate Technology
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    • v.6 no.1
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    • pp.28-36
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    • 2020
  • Sustainable appropriate technology requires user-centered design with consideration of the political, cultural and environmental aspects of the area. However, in the preparation of appropriate technology, there is a limit to the prior grasp of the user's intention and experience leading to the actual behavior of the user after the dissemination. As a result, appropriate technologies are often inconvenient for practical use or used for other purposes, contrary to the designer's intention. This study analyzes the case of appropriate technology with an analysis framework that reflects Maier's affordance theory, and proposes a design solution that can overcome the limitations of existing design. Affordance theory is the theory of factors that cause the user to identify and use features through interpretation based on prior knowledge and experience about things. The analysis cases in this study are the interviews with the designers, management education materials, and manager interviews for water purification systems at three of six schools in Binh Dinh Province, Vietnam, from August 2015 to January 2018. The case was attempted to be improved by periodic installation, maintenance, and inspection, but similar problems continued to occur. First, the facility inspections and manager interviews are compared with manager training materials distributed at the time of installation to find inconsistencies. Next, we analyze the designer's intended affordance and the affordances that actually influenced the management behavior. And then, we propose design solutions based on commonly found problems and affordances. This study suggests that it is necessary to apply the design considering the user's behavior before distributing the appropriate technology, and this study will be precedent in the process of finding the improvement through the analysis framework based on the affordance.

Science and Technology ODA Promotion of Korea through ICT of Global Problem Solving Centers -Suggestion on the mid- and short-term projects promotion of science and technology ODA roadmap- (글로벌문제해결거점 ICT화를 통한 한국형 과학기술 ODA 추진 -과학기술 ODA 중·단기 과제 추진에 대한 제언-)

  • Jung, Woo-Kyun;Shin, Kwanwoo;Jeong, Seongpil;Park, Hunkyun;Park, Eun Sun;Ahn, Sung-Hoon
    • Journal of Appropriate Technology
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    • v.7 no.2
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    • pp.162-171
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    • 2021
  • The Korean government proposed the K-SDGs in 2019 to promote the UN SDGs, but the role and tasks of science and technology, an important means of implementing the SDGs, have not been materialized. Accordingly, the role of science and technology ODA for the SDGs was established through the Ministry of Science and ICT's policy research project 'Science and Technology ODA Promotion Roadmap for Spreading the New Southern Policy and Realizing the 2030 SDGs'. In addition, goals, strategies, and core tasks for the next 10 years were derived in 10 fields such as water, climate change, energy, and ICT. In this paper, we analyze 30 key tasks of the ODA promotion roadmap for science and technology for the realization of SDGs, and propose mid- and short-term tasks and implementation plans for effective roadmap promotion. Among the key tasks in each field, four common elements were derived: ICT/smartization, a global problem-solving center, cooperation/communication platform, and business model/startup support platform/living lab that can create and integrate roadmap implementation conditions. In addition, the four mid- and short-term tasks, 1) Establishment of science and technology ODA network, 2) Establishment of living lab business platform linked to start-up support business, 3) Local smartization of recipient countries, and 4) Expand and secure sustainability of global problem-solving centers, were set in relation to the implementation of the detailed roadmap. For the derived mid- and short-term tasks, detailed implementation plans based on the ICTization of global problem-solving centers were presented. The implementation of the mid- and short-term tasks presented in this paper can contribute to the more effective achievement of the science and technology ODA roadmap, and it is expected that Korea's implementation of SDGs will also achieve high performance.

Future Prospects of Forest Type Change Determined from National Forest Inventory Time-series Data (시계열 국가산림자원조사 자료를 이용한 전국 산림의 임상 변화 특성 분석과 미래 전망)

  • Eun-Sook, Kim;Byung-Heon, Jung;Jae-Soo, Bae;Jong-Hwan, Lim
    • Journal of Korean Society of Forest Science
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    • v.111 no.4
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    • pp.461-472
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    • 2022
  • Natural and anthropogenic factors cause forest types to continuously change. Since the ratio of forest area by forest type is important information for identifying the characteristics of national forest resources, an accurate understanding of the prospect of forest type change is required. The study aim was to use National Forest Inventory (NFI) time-series data to understand the characteristics of forest type change and to estimate future prospects of nationwide forest type change. We used forest type change information from the fifth and seventh NFI datasets, climate, topography, forest stand, and disturbance variables related to forest type change to analyze trends and characteristics of forest type change. The results showed that the forests in Korea are changing in the direction of decreasing coniferous forests and increasing mixed and broadleaf forests. The forest sites that were changing from coniferous to mixed forests or from mixed to broadleaf forests were mainly located in wet topographic environments and climatic conditions. The forest type changes occurred more frequently in sites with high disturbance potential (high temperature, young or sparse forest stands, and non-forest areas). We used a climate change scenario (RCP 8.5) to establish a forest type change model (SVM) to predict future changes. During the 40-year period from 2015 to 2055, the SVM predicted that coniferous forests will decrease from 38.1% to 28.5%, broadleaf forests will increase from 34.2% to 38.8%, and mixed forests will increase from 27.7% to 32.7%. These results can be used as basic data for establishing future forest management strategies.