• Resources Recycling
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• v.20 no.1
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• pp.28-36
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• 2011

More than 50% of refractory materials generated from high-temperature melting furnace was not carbonized and could be recycled by adopting proper separation process. In the present work, the separation of refractory materials has studied by adopting color sorting technology to promote the recycling of waste refractory. Purity of the refractory materials was obtained with at 97.2%, color temperature of sorter light source 6,500K, which gives less interference of surrounding light source. Purity and separation efficiency were improved as size is setting bigger and lower conveyer belt speed. It is revealed that optimum conditions were color temperature 6,500K, conveyer belt speed 1,000 mm/sec, particle size -20 mm, etc. To improve purity and separation efficiency on below 10mm size, the resolution of should be fixed camera and it narrow recognition range. As a result of the study, color sorting technology could be used for separation of waste refractory materials and will contribute to promote the waste recycling.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.107-110
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• 2001

제철소에서 매년 대량 발생되어 주로 매립처분되고 있는 제강분진의 재활용 방안으로서, 폐수처리분야에 널리 사용되고 있는 펜톤산화공정의 반응촉매원인 Fe 공급원으로서 제강분 진의 활용 가능성에 대한 연구를 수행하였다. 본 연구에서는 포항제철소에서 제철부산물로 발생되는 제강분진을 전처리 없이 산화촉매로 사용하여 김포 수도권 매립지의 침출수 처리 공정에서 펜톤산화조에 유입되는 원수를 대상으로 과산화수소에 의한 산화처리 실험을 수행하였다. 반응은 회분식으로 수행하였으며, 일반적으로 알려진 펜톤산화반응의 주요 반응조 건인 운전 pH, 과산화수소 주입량 및 분할주입, 제강분진의 주입량 등의 변화에 따른 각 조 건별 시간에 따른 반응결과를 알아보았다. 또한 기존의 Fe 공급원으로 사용되고 있는 FeSO$_4$와 처리성능 및 적용조건에 대한 비교 실험도 수행하였다. 침출수 수질변화는 TOC (Total Organic Carbon) analyzer를 사용하여 측정한 TOC값으로 나타냈으며, pH controller 와 정량펌프를 사용하여 HCl과 NaOH주입을 통해 반응기간동안 일정 pH를 유지하였다. 본 연구결과, 최적 pH 조건인 4에서 최대 75% TOC 제거율을 나타내었으며, 대부분의 반응은 30분 이내에 이루어졌다. 주어진 실험조건에서 FeSO$_4$와 비교하여 반응속도와 처리효율에서 향상된 결과를 나타내었으며 반응 후 응집침전실험에서도 보다 높은 처리효과를 얻을 수 있었다. 결론적으로, 과산화수소/제강분진 시스템을 이용한 화학적 산화처리방법은 경제성과 처리성능에서 기존의 펜톤산화공정의 대체방안으로서 향 후 적용가능성이 높을 것으로 기대된다.g, 200 mg/kg, 300 mg/kg의 순서로 함량이 점차 감소하는 결과를 얻을 수 있었다. 이상의 결과를 종합하여 볼 때 가자 메탄올추출물은 PQ 유도독성을 신장 및 폐조직에서 효과적으로 경감시키는 것으로 나타났다.ted retailers ("sellers") must accept end-of-life items returned to them by the consumers. At the local level, Taipei City implements a pay-as-you-throw program, whereby citizens pay waste collection and treatment fees through the purchase of special trash bags approved by the Taipei City Government. However. recyclables that are separated by citizens are collected free-of-charge by the City. Taichung City and Kaohsiung City, on the other hand, enforce mandatory sorting schemes, whereby citizens face penalties if they don't separate recyclables from the trash before pick-up. These programs have resulted in a significant reduction in municipal waste. Per capita waste collected per day has dropped from 1.143

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.141-154
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• 2014

The adoption of International Financial Reporting Standards (IFRS) is the one of important issues in the recent accounting research because the change from local GAAP (Generally Accepted Accounting Principles) to IFRS has a substantial effect on accounting information. Over 100 countries including Australia, China, Canada and the European Union member countries adopt IFRS (International Financial Reporting Standards) for financial reporting purposes, and several more including the United States and Japan are considering the adoption of IFRS (International Financial Reporting Standards). In Korea, 61 firms voluntarily adopted Korean International Financial Reporting Standard (K-IFRS) in 2009 and 2010 and all listed firms mandatorily adopted K-IFRS (Korea-International Financial Reporting Standards) in 2011. The adoption of IFRS is expected to increase financial statement comparability, improve corporate transparency, increase the quality of financial reporting, and hence, provide benefits to investors This study investigates whether recognized accounts receivable discounting (AR discounting) under Korean International Financial Reporting Standard (K-IFRS) is more value relevant than disclosed AR discounting under Korean Generally Accepted Accounting Principles (K-GAAP). Because more rigorous standards are applied to the derecognition of AR discounting under K-IFRS(Korea-International Financial Reporting Standards), most AR discounting is recognized as a short term debt instead of being disclosed as a contingent liability unless all risks and rewards are transferred. In this research, I try to figure out industrial responses to the changes in accounting rules for the treatment of accounts receivable toward more strict standards in the recognition of sales which occurs with the adoption of Korea International Financial Reporting Standard. This study examines whether accounting information is more value-relevant, especially information on accounts receivable discounting (hereinafter, AR discounting) is value-relevant under K-IFRS (Korea-International Financial Reporting Standards). First, note that AR discounting involves the transfer of financial assets. Under Korean Generally Accepted Accounting Principles (K-GAAP), when firms discount AR to banks before the AR maturity, firms conventionally remove AR from the balance-sheet and report losses from AR discounting and disclose and explain the transactions in the footnotes. Under K-IFRS (Korea-International Financial Reporting Standards), however, most firms keep AR and add a short-term debt as same as discounted AR. This process increases the firms' leverage ratio and raises the concern to the firms about investors' reactions to worsening capital structures. Investors may experience the change in perceived risk of the firm. In the study sample, the average of AR discounting is 75.3 billion won (maximum 3.6 trillion won and minimum 18 million won), which is, on average 7.0% of assets (maximum 38.6% and minimum 0.002%), 26.2% of firms' accounts receivable (maximum 92.5% and minimum 0.003%) and 13.5% of total liabilities (maximum 69.5% and minimum 0.004%). After the adoption of K-IFRS (Korea-International Financial Reporting Standards), total liabilities increase by 13%p on average (maximum 103%p and minimum 0.004%p) attributable to AR discounting. The leverage ratio (total liabilities/total assets) increases by an average 2.4%p (maximum 16%p and minimum 0.001%p) and debt-to-equity ratio increases by average 14.6%p (maximum 134%p and minimum 0.006%) attributable to the recognition of AR discounting as a short-term debt. The structure of debts and equities of the companies engaging in factoring transactions are likely to be affected in the changes of accounting rule. I suggest that the changes in accounting provisions subsequent to Korea International Financial Reporting Standard adoption caused significant influence on the structure of firm's asset and liabilities. Due to this changes, the treatment of account receivable discounting have become critical. This paper proposes an intelligent diagnostic system for estimating negative impact on stock value with self-organizing maps and case based reasoning. To validate the usefulness of this proposed model, real data was analyzed. In order to get the significance of this proposed model, several models were compared to the research model. I found out that this proposed model provides satisfactory results with compared models.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.8
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• pp.866-871
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• 2006

The nutrient recovery in phosphate crystallization process was investigated by using laboratory scale uptlow reactors, adopting sequencing batch type configuration. The industrial waste lime was used as potential cation source with magnesium salt($MgCl_2$) as control. The research was focused on its successful application in a novel integrated sludge treatment process, which is comprised of a high performance fermenter followed by a crystallization reactor. In the struvite precipitation test using synthetic wastewater first, which has the similar characteristics with the real fermentation effluent, the considerable nutrient removal(about 60%) in both ammonia and phosphate was observed within $0.5{\sim}1$ hr of retention time. The results also revealed that a minor amount(<5%) of ammonia stripping naturally occurred due to the alkaline(pH 9) characteristic in feed substrate. Stripping of $CO_2$ by air did not increase the struvite precipitation rate but it led to increased ammonia removal. In the second experiment using the fermentation effluent, the optimal dosage of magnesium salt for struvite precipitation was 0.86 g Mg $g^{-1}$ P, similar to the mass ratio of the struvite. The optimal dosage of waste lime was 0.3 g $L^{-1}$, resulting in 80% of $NH_4-N$ and 41% of $PO_4-P$ removal, at about 3 hrs of retention time. In the microscopic analysis, amorphous crystals were mainly observed in the settled solids with waste lime but prism-like crystals were observed with magnesium salt. Based on mass balance analysis for an integrated sludge treatment process(fermenter followed by crystallization reactor) for full-scale application(treatment capacity Q=158,880 $m^3\;d^{-1}$), nutrient recycle loading from the crystallization reactor effluent to the main liquid stream would be significantly reduced(0.13 g N and 0.19 g P per $m^3$ of wastewater, respectively). The results of the experiment reveal therefore that the reuse of waste lime, already an industrial waste, in a nutrient recovery system has various advantages such as higher economical benefits and sustainable treatment of the industrial waste.

• Journal of Practical Agriculture & Fisheries Research
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• v.16 no.1
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• pp.193-206
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• 2014

The objectives of the project are to increase farmers' income through GAP and to reduce the loss of agricultural produce, for which the Korean partner takes a role of transferring needed technologies to the project site. To accomplish the project plan, it is set to implement the project with six components: construction of buildings, installation of agricultural facilities, establishment of demonstration farms, dispatching experts, conducting training program in Korea and provision of equipments. The Project Management Committee and the Project Implementation Team are consisted of Korean experts and senior officials from Department of Agriculture, Myanmar that managed the project systematically to ensure the success of the project. The process of the project are; the ceremony of laying the foundation and commencing the construction of training center in April, 2012. The Ribbon Cutting Ceremony for the completion of GAP Training Center was successfully held under PMC (MOAI, GAPI/ARDC) arrangement in SAl, Naypyitaw on June 17, 2012. The Chairman of GAPI, Dr. Sang Mu Lee, Director General U Kyaw Win of DOA, officials and staff members from Korea and Myanmar, teachers and students from SAl attended the ceremony. The team carried out an inspection and fixing donors' plates on donated project machineries, agro-equipments, vehicles, computers and printer, furniture, tools and so forth. Demonstration farm for paddy rice, fruits and vegetables was laid out in April, 2012. Twenty nine Korean rice varieties and many Korean vegetable varieties were introduced into GAP Project farm to check the suitability of the varieties under Myanmar growing conditions. Paddy was cultivated three times in DAR and twice in SAl. In June 2012, vinyl houses were started to be constructed for raising seedlings and finished in December 2012. Fruit orchard for mango, longan and dragon fruit was established in June, 2012. Vegetables were grown until successful harvest and the harvested produce was used for panel testing and distribution in January 2013. Machineries for postharvest handling systems were imported in November 2012. Setting the washing line for vegetables were finished and the system as run for testing in June 2013. New water tanks, pine lines, pump house and electricity were set up in October 2013.

• Tunnel and Underground Space
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• v.34 no.4
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• pp.393-412
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• 2024

In selecting a disposal site for high-level radioactive waste, the hydrogeological research of the site is very important, and the hydraulic conductivity and the storage coefficient are key parameters. In this study, the hydraulic conductivity obtained by two different types of field hydraulic test equipment and methods was compared and analyzed for the deep granite rockmass in the Wonju area to understand the hydraulic characteristics of the deep granite rockmass. One was to perform the lugeon test, constant pressure injection test, and slug test at a maximum depth of 602.0 m by using the auto pressure/flow injection system, and the calculated hydraulic conductivity ranged from 1.26E-9 to 4.16E-8 m/s. In the overall depth, the maximum and minimum differences of the hydraulic conductivity were found to be about 33 times, and in the same test section, the difference by test method or analysis method was 1.13 to 8.25 times. In the other, the hydraulic conductivity calculated by performing a constant pressure injection test and a pulse test at a maximum depth of 705.1 m using the deep borehole hydraulic testing system was found to be 1.60E-10 to 2.05E-8 m/s, and the maximum and minimum differences were found to be about 130 times. In the constant pressure injection test, the difference depending on the analysis method was found to be 1.02 to 2.8 times. The hydraulic conductivity calculated by the two test equipment and methods generally showed similar ranges as E-9 and E-8 m/s, and no clear trend was observed according to depth. It was found that the granite rockmass in the Wonju area where the field hydraulic test was conducted showed low or very low rockmass permeability, and although there are differences in the range of hydraulic conductivity and the depth of application that can be measured depending on the applied test equipment and test method, it is generally believed that reliable results were presented.

• Journal of the korean veterinary medical association
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• v.44 no.9
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• pp.803-818
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• 2008

동물의 결핵은 Mycobacterium bovis의 감염에 의한 만성 소모성 질병이며 인수공통전염병이다. 동물로부터 사람으로의 결핵 전염은 생유 섭취하던 시대에 상당히 많이 보고되었다. 우유의 살균처리와 소에서 피내진단에 의한 양성우 살처분 및 보상금 지급 정책을 전개하면서 M. bovis의 사람전염은 급격히 감소하였다. 소 결핵은 우리나라에서 연간 0.15% 내외의 발생을 보이고 있으며, 발생의 주원인으로는 외부입식소, 인근발생농장, 과거발생농장의 사후관리소홀 등이다. 사람 결핵의 주원인균인 M. tuberculosis와 M. bovis는 유전체가 99.9% 유사하며, M. bovis를 M. tuberculosis의 아종으로 분류하기도 한다. 두 세균은 M. tuberculosis complex에 속하며, M. tuberculosis와 M. bovis이외에도 M. africanum, M. canettii, M. microti, M. pinnipedii 등이 있다. M. bovis는 M. tuberculosis complex중에서 가장 넓은 숙주범위를 가진다. M. bovis의 대표적인 숙주는 종이름에도 나타나 있듯이 소이다. 소결핵 전파원으로서는 M. bovis에 감염된 소가 가장 중요하다. 소 이외에도 면양, 산양, 말, 돼지, 사슴, 엘크, 영양 (antelope, kudus, elands, sitatungas, oryxes, addaxes), 개, 고양이, 흰족제비 (ferrets), 낙타, 여우, 밍크, 오소리, 쥐, 영장류, 라마, 맥 (tapirs), 코끼리, 코뿔소 (rhinoceroses), 주머니쥐, 땅다람쥐 (ground squirrels), 수달 (otters), 물개, 산토끼 (hares), 두더쥐 (moles), 너구리 (raccoons), 코요테, 사자, 호랑이, 표범, 살쾡이 (lynx) 등에 감염될 수 있으나, 대부분 종결숙주 (spillover host)로 가축의 결핵방제가 유지되고 있는 국가에서는 야생동물 결핵의 가축 전염이 문제시되고 있다. M. bovis는 주로 호흡기와 소화기를 통하여 감염되며, 결핵결절이 형성되는 부위를 관찰하면 감염경로를 추정할 수 있다. 결핵에 감염되면, 초기에는 뚜렷한 임상증상을 보이지 않으나, 아침, 추운 날씨, 또는 운동 중에 심한 기침을 하며, 호흡곤란을 일으킬 수 있다. 결핵은 감염되어도 대부분 무증상이기 때문에 피내진단, 결핵결절 병리소견, 원인균 분리 등에 의해 진단하여야 한다. 감염된 결핵균은 탐식세포에 탐식되어 특징적인 육아종성 결절 병변으로 진행된다. 현재 결핵은 피내진단과 결핵결절 병리소견 등에 의해 판정하고 있다. 최신 진단법으로는 피내진단을 대체할 수 있는 인터페론 감마 검사법과 우군의 결핵 스크리닝과 말기 결핵 검사에 우수한 항체진단법이 개발되어 있다. 그러나, 소 결핵 근절을 위해서는 일관성있는 진단법과 진단기준을 적용하는 것이 중요한 성공요인중 하나이다. 소결핵 청정국인 호주와 캐나다에서는 피내진단과 도축장 결절검사를 결핵 양성우 색출방법의 근간으로 삼고 있으며, 소결핵 근절의 최종단계에 이르러서는 특이적인 검사법을 적용하였지만, 근절목적상 민감성이 높은 피내진단법을 사용하였다. 이와 더불어, 피내진단 양성우의 부검소견과 원인균 분리를 통해 결핵을 확진하여 출처농장의 역추적 검사를 통하여 결핵 양성소를 제거하였다. 한편, 결핵의 농장간 및 지역간 전파방지를 위해 결핵 청정농장과 결핵 오염농장, 결핵 청정지역과 결핵 오염지역 구분을 통하여 결핵 오염농장과 결핵 오염지역으로부터 결핵 청정농장과 결핵 청정지역으로의 이동전 결핵 검진을 통해 개체 이동에 따른 결핵 전파를 근본적으로 차단하는 시스템을 엄격히 적용한 것이 주요한 성공 요인중 하나였다. 호주 결핵 근절정책 성공요인을 요약하면, 일관성 있는 결핵진단법 적용, 양성우 출처농장의 철저한 역추적 검사, 개체 이동전 결핵 음성증명 확인, 농가단체의 경제적 및 방역상 적극적인 지원 및 협조 결핵의 지속적인 모니터 링과 현장요구에 부응하는 방제신기술의 지속적인 연구개발 등을 들 수 있다. 최근 들어 국내 동물 결핵은 소, 특히, 한우의 결핵발생이 증가하고 있으며, 사슴 결핵발생도 증가하고 있다. 농장간 및 지역간에 결핵 감수성 가축, 특히, 소와 사슴의 거래가 아주 복잡하게 이루어지고 있는 현실을 고려할 때, 결핵전파의 주원인인 결핵감염 소나 사슴의 농장내 반입을 철저히 차단해야 할 것이다. 이때, 개체 검사는 물론이고, 출처농장에 대한 결핵 음성을 확인한 후 입식하여야 할 것이며, 입식 후에도 60일정도 격리사육하면서 피내진단등 결핵검진 후 음성인 경우에만 합사하여야 할 것이다. M. bovis는 사람을 비롯한 거의 모든 온혈동물에서 결핵을 일으킬 수 있기 때문에, 결핵 감염소로 판정된 농장 종사자는 각 시도 보건소의 협조를 받아 결핵검진을 받도록 해야 한다. 농장 가축에 접촉할 수 있는 야생동물의 접촉을 차단하여야 하며, 특히, 농장 사료의 야생동물에 의한 오염을 방지할 수 있는 사료창고관리를 철저히 해야 한다. 결핵 감염소를 다룰 때는 분비물 또는 가검물에 의해 감염될 수 있기 때문에 개인방역장비 - 방역복, 마스크, 비닐장갑, 비닐장화 - 를 착용한 상태에서 다루어야 한다. 특히, 결핵 감염소를 매몰 또는 소각하는 과정에서 결핵 감염소의 배설물 및 분비물 처리를 철저히 하여야 한다. 모든 작업을 마친 후에는 개인방역장비, 매몰 또는 소각에 사용하였던 장비 등을 청소 및 소독하고 필요시 소각 또는 매몰하여야 하며, 개인감염위험과 타인 감염위험을 방지하기 위해 노출부위를 세척하여야 한다.

• Journal of vocational education research
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• v.37 no.5
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• pp.25-53
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• 2018

The purpose of this study is to find out the improvement plan through the satisfaction survey of the trainees involved in vocational training fraud preventive education. In order to do this, we conducted a satisfaction survey(4,263 persons) of 5,939 people who participated in the prevention education conducted by group education or e-learning in 2017. Finally we collected 4,237 effective responses data. Descriptive statistics and the regression analysis were conducted. The finding of the study were as follows. First, the education service quality(4.42), satisfaction level(4.44), understanding level(4.44) and help level(4.45) were significantly higher than those of participants in the preventive education 4 and above. Second, e-learning participants' perceived level of education service quality, satisfaction, comprehension, and help was higher in all variables than collective education's. Third, all of the sub-factors of preventive education service quality influenced satisfaction, understanding, and help in collective education and e-learning, respectively. In the collective education, the contents of education had the greatest influence, and in e-learning, the data composition had the greatest influence. Fourth, desirable education contents were cases of fraud training(70.7%), disposition regulations(47.9%), NCS course operation instructions(32.8%) and training management best practices(32.4%). Additional requirements also included the establishment of an in-depth course, the provision of anti-fraud education content for trainees, and screen switching and system stability that can be focused on e-learning. Therefore, this study suggests that first, it is necessary to activate e-learning for prevention education more, reflecting satisfaction of e-learning is higher than that of collective education. Second, it is necessary to diversify the content of preventive education and to provide it more abundantly, because it has the biggest influence in common with the satisfaction, understanding and help level of the preventive education. Third, education content next, the factors that have a relatively big influence on satisfaction are shown as delivery method and education place in the collective education. Therefore, it is necessary to prepare education place considering the assignment of instructor and convenience. Fourth, constructing data next, the factor that have a relatively great influence on understanding and help are found to be operator support, and more active operator support activities are required in e-learning. Fifth, it is required to delivery prevention activity for trainees participating in vocational training. Sixth, it is necessary to analyze the educational need to construct the contents of preventive education more systematically.

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.334-346
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• 2022

There is a lack of knowledge and information on the understanding and application of the Process Safety Management (PSM) system, recognized as a major cause of industrial accidents in small-and medium-sized workplaces. Hence, it is necessary to prepare a protocol to secure the practical and continuous levels of implementation for PSM and eliminate human errors through tracking management. However, insufficient research has been conducted on this. Therefore, this study investigated and analyzed the various violations in the administrative measures, based on the regulations announced by the Ministry of Employment and Labor, in approximately 200 small-and medium-sized PSM workplaces with fewer than 300 employees across in korea. This study intended to contribute to the prevention of major industrial accidents by developing a facility maintenance web program that removed human errors in small-and medium-sized workplaces. The major results are summarized as follows. First, It accessed the web via a QR code on a smart device to check the equipment's specification search function, cause of failure, and photos for the convenience of accessing the program, which made it possible to make requests for the it inspection and maintenance in real time. Second, it linked the identification of the targets to be changed, risk assessment, worker training, and pre-operation inspection with the program, which allowed the administrator to track all the procedures from start to finish. Third, it made it possible to predict the life of the equipment and verify its reliability based on the data accumulated through the registration of the pictures for improvements, repairs, time required, cost, etc. after the work was completed. It is suggested that these research results will be helpful in the practical and systematic operation of small-and medium-sized PSM workplaces. In addition, it can be utilized in a useful manner for the development and dissemination of a facility maintenance web program when establishing future smart factories in small-and medium-sized PSM workplaces under the direction of the government.

• Korean Journal of Mineralogy and Petrology
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• v.37 no.2
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• pp.47-57
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• 2024

Jarosite, a mineral belonging to the alunite family, is found in various low pH environments and can incorporate cations or oxyanions into its structure, either by coprecipitation or substitution. This mineral is sensitive to pH changes and can easily transform into goethite upon geochemical changes, such as an increase in pH. This transformation can release toxic ions from the jarosite, potentially causing additional environmental damage. In addition to potassium (K), sodium (Na) and ammonium (NH₄) can also substitute for cations in jarosite. The formation of jarosites containing these and other cations is significant not only for acid mine drainage but also for the smelting industry. In this study, three different types of jarosites containing various cations were synthesized and the phase transformation of each jarosite to goethite upon pH change were compared. All the jarosites were sensitive to pH changes, showing much higher rates of phase change at pH 8 than at pH 4. At the relatively low pH of 4, the phase transformation of K-jarosite, which is most stable in structure, to goethite was the slowest. For the other two jarosites, the cations have either smaller or larger radii than K ions, resulting in differences in structural stability and they showed more rapid transformations to goethite. However, at pH 8, K-jarosite exhibited a much more rapid transformation to goethite than the other jarosites, which was also evident from the rapid increase in K ions in aqueous solution. The mineral transformation behavior of K-jarosite at higher pH is significantly different from that at lower pH, indicating that the mechanism of the transformation to goethite differs between these conditions, which requires further investigation. The results of this study indicate that the mineral transformation of jarosite in acid mine drainage or smelter waste disposal may significantly influence the behavior of heavy metals. This research provides valuable insights for predicting the behavior of heavy metals in smelting industry waste disposal.