• Title/Summary/Keyword: Environment Standard

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Predicting Concentrations of Soil Pollutants and Mapping Using Machine Learning Algorithms (기계학습을 통한 토양오염물질 농도 예측 및 분포 매핑)

  • Kang, Hyewon;Park, Sang Jin;Lee, Dong Kun
    • Journal of Environmental Impact Assessment
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    • v.31 no.4
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    • pp.214-225
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    • 2022
  • This study emphasized the soil of environmental impact assessment to devise measures to minimize the negative impact of project implementation on the environment. As a series of efforts for impact assessment procedures, a national inventory-based database was established for urban development projects, and three machine learning model performance evaluation as well as soil pollutant concentration distribution mapping were conducted. Here, nine soil pollutants were mapped to the metropolitan area of South Korea using the Random Forest model, which showed the best performance. The results of this study found that concentrations of Zn, F, and Cd were relatively concerned in Seoul, where urbanization is the most active. In addition, in the case of Hg and Cr6+, concentrations were detected below the standard, which was derived from a lack of pollutants such as industrial and industrial complexes that affect contents of heavy metals. A significant correlation between land cover and pollutants was inferred through the spatial distribution mapping of soil pollutants. Through this, it is expected that efficient soil management measures for minimizing soil pollution and planning decisions regarding the location of the project site can be established.

A Design of Ultra Compact S-Band PCM/FM Telemetry Transmitter (초소형 S-대역 PCM/FM 텔레메트리 송신기 설계 및 제작)

  • Jun, Ji-ho;Park, Ju-eun;Kim, Seong-min;Min, Se-hong;Lee, Jong-hyuk;Kim, Bok-ki
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.50 no.11
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    • pp.801-807
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    • 2022
  • In this paper, we propose an ultra compact S-Band PCM/FM telemetry transmitter. The equipment is compact, so it can be applied to a limited space and capable of stable data transmission was designed and manufactured even with specifications set differently for each operating environment and system. RF direct conversion structure is used for the miniaturization of equipment, an RF transmission board, Power distribution board, and a signal processing board were implemented on a single PCB, so that the function of the transmitter could be performed with a minimum device. According to the target specification, variable output of 1~10W and variable data rate of 390kbps~12.5Mbps is possible in S-Band(2,200~2,400MHz) without degradation of performance. To verify the performance of the equipment, the RF performance test and BER measurement test were performed after the equipment was manufactured. It was confirmed that the OBW, null-to-null bandwidth, 1st IMD, Spurious emission, Phase noise specification of the PCM/FM modulated signal which is presented by the IRIG standard were satisfied, and we can confirm the data received using the transmitter inspection equipment were transmitted normally without distortion.

Suggestion of Evaluation Elements Based on ODD for Automated Vehicles Safety Verification : Case of K-City (자율주행자동차 안전성 검증을 위한 ODD 기반 평가요소 제시 : K-City를 중심으로)

  • Kim, Inyoung;Ko, Hangeom;Yun, Jae-Woong;Lee, Yoseph;Yun, Ilsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.21 no.5
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    • pp.197-217
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    • 2022
  • As automated vehicle(AV) accidents continue to occur, the importance of safety verification to ensure the safety and reliability of automated driving system(ADS) is being emphasized. In order to encure safety and reliability, it is necessary to define an operational design domain(ODD) of the ADS and verify the safety of the ADS while evaluating its ability to respond in situations outside of the ODD. To this, international associations such as SAE, BSI, NHTSA, ISO, etc. stipulate ODD standards. However, in Korea, there is no standard for the ODD, so automated vehicles's ODD expression method and safety verification and evaluation are not properly conducted. Therefore, this study analyzed overseas ODD standards and selected suitable ODD for safety verification and evaluation, and presented evaluation elements for ADS safety verification and evaluation. In particular, evaluation elements were selected by analyzing the evaluation environment of the automated driving experimental city (K-City) that supports the development of ADS technology.

Evaluation of the acoustic environments of open-plan offices in Korean public buildings (국내 공공건축물 개방형 사무실 음환경 평가)

  • Sang Hee Park;Hye-Kyung Shin;Seung-Min Lee;Kyoung Woo Kim
    • The Journal of the Acoustical Society of Korea
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    • v.42 no.1
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    • pp.42-49
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    • 2023
  • Poor indoor acoustic environments negatively affect occupants. Previous research has shown that indoor acoustic environments affect not only task performance and job satisfaction of the occupants, but also their health and well-being. This study aimed for evaluating indoor acoustic environments of open-plan offices located in public buildings in Korea. It also aimed to review the matters that need to be considered in order to improve occupants' acoustic comfort. Indoor noise levels were measured in 13 sites; the measurements were conducted for five consecutive working days from Monday to Friday. The noise levels were evaluated based on the levels recommended by the ISO and the EU ALDREN project. The study found that most of the indoor noise levels measured in the sampled sites during the working hours met the ISO standard. In the case of the levels under unoccupied conditions at night, those at three sites did not meet the recommendation of the ALDREN. In addition, some characteristics of the sites had significant effects on the noise level. Since the exact acoustic performance of the building envelope could not be identified, future research is needed for investigating the relationship between accurate building performance and indoor acoustic environments.

Verification of Validity on Awareness Tool of Business Continuity for Railway Organizations (철도기관을 대상으로 한 사업연속성 인식도구의 타당성 검증)

  • Jeong-ho Chang;Chong-soo Cheung
    • Journal of the Society of Disaster Information
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    • v.19 no.1
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    • pp.195-203
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    • 2023
  • Purpose: This study intends to check validity of tools for awareness of Business Continuity through measurement and analysis on the sub factors of Business Continuity by employees of railway-related organizations. Method: Based on the preceding study, sub factors of the awareness of Business Continuity are divided into 7 and the total of 29 questions were delivered to employees of railway-related organizations for investigation and analysis through the online survey tool. Result: According to EFA result, the number of factors of awareness of Business Continuity based on the theoretical ground was reduced to 7 and the total coefficient of determination was 82.616%. Checking the questions by factor, all the questions were loaded as intended. Conclusion: Validity of measurement tools of Business Continuity whose sub factors are the Context of Organization, Leadership, Planning, Operation, Support, Performance evaluation, and Improvement for railway organizations were secured through the Exploratory Factor Analysis of this study. As for the further tasks, studies on the structural relationship among internalization of business continuity, organization effectiveness, learning support environment, etc are required.

Behavioral Change of Workers who completed Experiential Safety Training (체험식 안전교육 이수 근로자의 행동 변화 연구)

  • Choonhwan, Cho
    • Journal of the Society of Disaster Information
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    • v.19 no.1
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    • pp.161-172
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    • 2023
  • Safety education delivered to construction workers in a lecture manner has limitations in concentration and immersion, so delivery power and interest are low. In order to improve unstable behavior through education and prevent safety accidents, it is necessary to change the paradigm to hands-on education. Purpose: Experiential safety education aims to contribute to preventing accidents for construction workers by quickly recognizing risks, improving emergency response skills, and verifying the effectiveness of pre- and post-learning. Method: Based on a survey of workers who experienced the same work environment as the actual construction site, an opinion survey on the pre- and post-safety experience education and a variable measurement tool were planned, and a research hypothesis was established. Results: The Bayesian theory and MC simulation analysis were used to analyze the structural equation model, and the change in construction worker behavior was confirmed through the intended safety (A), non-experiential education in the sub-area of anxiety (B), average, standard deviation, and minimum and maximum values. Conclusion: The effect of education and industrial accidents are reduced only when construction workers are motivated to participate.

Current Status and Prospects for Standards, Regulations, and Detection of Probiotic Yogurt: Review (프로바이오틱 요구르트의 기준, 규정, 검출에 관한 현황 및 전망: 총설)

  • Jung-Whan Chon;Kun-Ho Seo;Tae-Jin Kim;Hye-Young Youn;Seok-Hyeong Kang;Won-Uk Hwang;Hajeong Jeong;Dongkwan Jeong;Kwang-Young Song
    • Journal of Dairy Science and Biotechnology
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    • v.41 no.1
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    • pp.9-25
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    • 2023
  • Yogurt fermentation is known to be beneficial because it provides a low pH and harsh environment for foodborne pathogens and improves organoleptic properties. Additionally, organic acids produced through fermentation have a good effect on the viscosity and gelling properties of yogurt. Several potential health benefits of probiotic and generally recognized as safe strains have been suggested. Yogurt is the preferred vehicle for delivering probiotics to health-conscious consumers. Therefore, manufacturers of probiotic beverages must comply with the relevant regulations. The development of probiotic yogurt begins with the selection of strains with safety and functional properties of probiotics. The selected probiotic strain should be technically suitable for viability and improve organoleptic quality while maintaining the number of bacteria above the standard value during processing and storage conditions. In addition, the efficacy of probiotic strains contained in yogurt should be investigated, confirmed, and approved according to well-designed clinical trials. Although various methods are used to detect probiotic strains, the recently widely used next generation sequencing method can be actively utilized. In the future, more research should be conducted with the latest methods to identify probiotic functions and accurately detect probiotic strains.

Foodservice Status and Perception regarding Foodservice Management in Kindergartens attached to Elementary Schools in Seoul (서울 소재 병설유치원의 급식운영 현황 및 급식운영 관리에 대한 인식 조사: 초등학교 교장과 유치원 원감을 대상으로)

  • Ranmi, Jung;Gun-Hee, Kim;Jieun, Oh;Sunny, Ham;Seungmin, Lee
    • Korean Journal of Community Nutrition
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    • v.27 no.6
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    • pp.492-502
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    • 2022
  • Objectives: This study examines the foodservice status of kindergartens attached to elementary schools in Seoul. We further determine the perception of elementary school principals and kindergarten assistant principals on the foodservice management for kindergartens. Methods: This survey was conducted from July 17 to 23, 2019, enrolling 207 kindergartens attached to elementary schools in Seoul. Questionnaires were sent to principals of elementary schools and assistant principals of kindergartens, and the data obtained from 89 kindergartens were included in the analysis. The questionnaire consisted of four parts: general information on subjects, foodservice management status, foodservice management status during elementary school vacations, and the perception of principals of elementary schools and assistant principals of kindergartens on foodservice management. Data are presented as frequency and percentage or mean and standard deviation. Statistical comparison between principals of elementary schools and assistant principals of kindergartens was conducted by paired t-test, chi-square test, and Pearson's correlation analysis. Results: A separate menu (10.1%) or recipe (20.2%) that considers preschooler characteristics was rarely used for foodservice at kindergartens attached to elementary schools. Most kindergartens did not have a separate dining space (3.4%) or a dedicated cook (93.3%). Although most kindergartens (92.1%) had operational foodservice during elementary school vacations, non-professional staff and non-nutrition teacher were mainly in charge of organizing the menu and purchasing ingredients (34.1% and 41.5%, respectively). The rate of using a contract catering company (28.0%, 23.2%) was also high. Both elementary school principals and assistant principals of kindergartens showed a high perception of the necessity for providing responsibility allowances for nutrition teachers and improving the cooking environment for kindergartens during elementary school vacations. Conclusions: There is a need for policies and administrative support measures to improve the quality of foodservices for kindergartens attached to elementary schools.

Phytochemical, Antidiabetic, Antioxidant, Antibacterial, Acute and Sub-Chronic Toxicity of Moroccan Arbutus unedo Leaves

  • Latifa Doudach;Hanae Naceiri Mrabti;Samiah Hamad Al-Mijalli;Mohamed Reda Kachmar;Kaoutar Benrahou;Hamza Assaggaf;Ahmed Qasem;Emad Mohamed Abdallah;Bodour Saeed Rajab;Khouloud Harraqui;Mouna Mekkaoui;Abdelhakim Bouyahya;Moulay El Abbes Faouzi
    • Journal of Pharmacopuncture
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    • v.26 no.1
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    • pp.27-37
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    • 2023
  • Objectives: Moroccan Arbutus unedo is an essential medicinal plant; however, little is known about the biological properties of its leaves mentioned in Moroccan traditional medicine. Methods: Various standard experiments were performed to evaluate the phytochemical, antidiabetic, antioxidant, antibacterial, and acute and sub-chronic toxicity characteristics of A. unedo leaves. Results: Phytochemical screening led to the identification of several phytochemical classes, including tannins, flavonoids, terpenoids, and anthraquinones, with high concentrations of polyphenols (31.83 ± 0.29 mg GAEs/g extract) and flavonoids (16.66 ± 1.47 mg REs/g extract). Further, the mineral analysis revealed high levels of calcium and potassium. A. unedo extract demonstrated significant antioxidant and anti-diabetic activities by inhibiting α-amylase (1.350 ± 0.32 g/mL) and α-glucosidase (0.099 ± 1.21 g/mL) compared to the reference drug Acarbose. Also, the methanolic extract of the plant exhibited significantly higher antibacterial activity than the aqueous extract. Precisely, three of the four examined bacterial strains exhibited substantial susceptibility to the methanolic extract . Minimum bactericidal concentration (MBC)/minimum inhibitory concentration (MIC) values indicated that A. unedo harbor abundant bactericidal compounds. For toxicological studies, mice were administered with A. unedo aqueous extract at single doses of 2,000 and 5,000 mg/kg. They did not exhibit significant abnormal behavior, toxic symptoms, or death during the 14-day acute toxicity test and the 90-day sub-chronic toxicity test periods. The general behavior, body weight, and hematological and biochemical status of the rats were assessed, revealing no toxicological symptoms or clinically significant changes in biological markers observed in the mice models, except hypoglycemia, after 90 days of daily dose administration. Conclusion: The study highlighted several biological advantages of A. unedo leaves without toxic effects in short-term application. Our findings suggest that conducting more comprehensive and extensive in vivo investigations is of utmost importance to identify molecules that can be formulated into pharmaceuticals in the future.

Health Risk Assessment by Exposure to Heavy Metals in PM2.5 in Ulsan Industrial Complex Area (울산 산단지역 PM2.5 중 중금속 노출에 의한 건강위해성평가)

  • Ji-Yun Jung;Hye-Won Lee;Si-Hyun Park;Jeong-Il Lee;Dan-Ki Yoon;Cheol-Min Lee
    • Journal of Environmental Health Sciences
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    • v.49 no.2
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    • pp.108-117
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    • 2023
  • Background: When particles are absorbed into the human body, they penetrate deep into the lungs and interact with the tissues of the body. Heavy metals in PM2.5 can cause various diseases. The main source of PM2.5 emissions in South Korea's atmosphere has been surveyed to be places of business. Objectives: The concentration of heavy metals in PM2.5 near the Ulsan Industrial Complex was measured and a health risk assessment was performed for residents near the industrial complex for exposure to heavy metals in PM2.5. Methods: Concentrations of heavy metals in PM2.5 were measured at four measurement sites (Ulsan, Mipo, Onsan, Maegok) near the industrial complexes. Heavy metals were analyzed according to the Air Pollution Monitoring Network Installation and Operation Guidelines presented by the National Institute of Environmental Research. Among them, only five substances (Mn, Ni, As, Cd, Cr6+) were targeted. The risk assessment was conducted on inhalation exposure for five age groups, and the excess cancer risk and hazard quotient were calculated. Results: In the risk assessment of exposure to heavy metals in PM2.5, As, Cd, and Cr6+ exceeded the risk tolerance standard of 10-6 for carcinogenic hazards. The highest hazard levels were observed in Onsan and Mipo industrial complexes. In the case of non-carcinogenic hazards, Mn was identified as exceeding the hazard tolerance of 1, and it showed the highest hazard in the Ulsan Industrial Complex. Conclusions: This study presented a detailed health risk from exposure to heavy metals in PM2.5 by industrial complexes located in Ulsan among five age groups. It is expected to be utilized as the basis for preparing damage control and industrial emission reduction measures against PM2.5 exposure at the Ulsan Industrial Complex.