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Measurement and analysis of PM10 and PM2.5 from chimneys of coal-fired power plants using a light scattering method (광산란법을 이용한 국내 석탄화력발전소 굴뚝에서 배출되는 PM10, PM2.5 측정 및 분석)

  • Shin, Dongho;Kim, Younghun;Hong, Kee-Jung;Lee, Gunhee;Park, Inyong;Kim, Hak-Joon;Kim, Yong-Jin;Han, Bangwoo;Hwang, Jungho
    • Particle and aerosol research
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    • v.16 no.4
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    • pp.131-140
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    • 2020
  • Air pollutants emitted from chimneys of coal-fired power plants are considered to be a major source of fine particulate matter in the atmosphere. In order to manage fine particle in the chimney of a coal-fired power plant, it is necessary to know the concentration of fine particle emitted in real time, but the current system is difficult. In this study, a real-time measurement system for chimney fine particle was developed, and measurements were performed on six coal-fired power plants. Through the measurements, the mass concentration distribution according to the particle size could be secured. All six chimneys showed bimodal distribution, and the count median diameters of each mode were 0.5 and 1.1 ㎛. In addition, it was compared with the gravimetric measurement method, and it was determined that the relative accuracy for PM10 was within 20%, and the value measured using the developed measuring instrument was reliable. Finally, three power plants were continuously measured for one month, and as a result of comparing the concentration of PM10 according to the amount of power generation, it was confirmed that the PM10 discharged from the chimney increased in the form of an exponential function according to the amount of power generation.

Phytochemical analysis of Panax species: a review

  • Yang, Yuangui;Ju, Zhengcai;Yang, Yingbo;Zhang, Yanhai;Yang, Li;Wang, Zhengtao
    • Journal of Ginseng Research
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    • v.45 no.1
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    • pp.1-21
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    • 2021
  • Panax species have gained numerous attentions because of their various biological effects on cardiovascular, kidney, reproductive diseases known for a long time. Recently, advanced analytical methods including thin layer chromatography, high-performance thin layer chromatography, gas chromatography, high-performance liquid chromatography, ultra-high performance liquid chromatography with tandem ultraviolet, diode array detector, evaporative light scattering detector, and mass detector, two-dimensional high-performance liquid chromatography, high speed counter-current chromatography, high speed centrifugal partition chromatography, micellar electrokinetic chromatography, high-performance anion-exchange chromatography, ambient ionization mass spectrometry, molecularly imprinted polymer, enzyme immunoassay, 1H-NMR, and infrared spectroscopy have been used to identify and evaluate chemical constituents in Panax species. Moreover, Soxhlet extraction, heat reflux extraction, ultrasonic extraction, solid phase extraction, microwave-assisted extraction, pressurized liquid extraction, enzyme-assisted extraction, acceleration solvent extraction, matrix solid phase dispersion extraction, and pulsed electric field are discussed. In this review, a total of 219 articles published from 1980 to 2018 are investigated. Panax species including P. notoginseng, P. quinquefolius, sand P. ginseng in the raw and processed forms from different parts, geographical origins, and growing times are studied. Furthermore, the potential biomarkers are screened through the previous articles. It is expected that the review can provide a fundamental for further studies.

Development of Gold Amalgam Voltametric Microelectrode for the Quantification of O2, Fe2+, Mn2+, and HS- (퇴적물 공극수내 O2, Fe2+, Mn2+ 및 HS- 센싱을 위한 금아말감 미세전극 개발)

  • Kwon, Soongil;Park, Donggeun;Choi, Geunyoung;Sung, Jaebin;Kim, Hyunsoo;Lee, Jae Woo;Hong, Yongseok
    • Journal of Korean Society on Water Environment
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    • v.38 no.2
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    • pp.103-112
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    • 2022
  • A gold amalgam voltammetric microelectrode (GAVM) system was developed for the quantification of dissolved biogeochemical species, such as O2, Fe2+, Mn2+, and HS- in sediment porewater. Commercially available Ag/AgCl and platinum electrodes were used as the reference and counter electrode, respectively, and a gold amalgam microelectrode was fabricated in the laboratory using 150-um diameter gold wire and a borosilicate capillary tube with a 1.6-mm diameter. A portable potentiostat (Metrohm, DropSens) was used for the application of voltage sweeping and to acquire the electric current. For sediment profiling, a commercially available actuator was customized and modified. The analysis method used in the system used the most widely used analysis method among the electrochemical analysis currently used The GAVM system was successively calibrated with the species and applied to estuarine sediments. The porewater analysis showed that the oxygen concentration was decreased to zero at a depth of 0.6 mm, and maximum Mn2+ and Fe2+ concentrations of 50 uM and 20 uM were detected at 2 and 3-cm depths, respectively. Maximum HS- concentrations of 10 uM were detected at 4 cm in the deeper sediments. The GAVM system was successfully developed and applied to the sediment and can be used to better understand biogeochemical reactions.

A Study on the Gender Rights Protection System in Arts and Cultural Industry (문화예술계 성 인권 보호를 위한 제도 연구)

  • Byun, Young geon;Lee, Sung yeop
    • Korean Association of Arts Management
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    • no.54
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    • pp.155-184
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    • 2020
  • This study aims to examine the system for gender rights in arts and cultural industry triggered by #Metoo movement and to suggest action plans to improve gender equality. Up until now, Korean government launched 'Pan-governmental Counter Plan', 'Recommendation of the Special Center for Investigating Sexual Harassment and Sexual Violence in Arts and Cultural Industries' 'the Primary and Secondary Supplemental Measures to Eradicate Sexual Harassment and Sexual Violence in the Arts and Cultural Sector by the Ministry of Culture, Sports and Tourism in Korea', and '2030 Cultural Vision'. Korean government has designed the system to protect gender rights using these proposals. Implemented policies can be grouped into 4 different categories; protecting victims, punishing abusers, implementing preventive measures, and reforming legal system. However, despite Korean government's multilateral efforts, continuous criticism aroused as policies failed to witness actual impacts in the industry. Given the fact that 2 years have passed since the launch of gender equality policy in cultural sector, this is the right time to discuss the current status and ways to improve it. For above reasons, research was conducted on documents including, but not limited to, government publications and an analysis of interviews with 9 major stakeholders of policy planning and implementation. During the study, interviews were analyzed using the qualitative research program MAXQDA. As a result, 5~10 problems were revealed in each category of the system. Furthermore, meaningful correlation has been found in improvement areas suggested by the interviewees. This connection implies that the policy for gender rights in arts and cultural industry shall be developed organically in order for the system to work.

Necessity of revision of the mandatory medication guidance regulation under the Pharmaceutical Affairs Act (약사법상 복약지도의무 규정의 개정 필요성)

  • Dawoon Jung
    • The Korean Society of Law and Medicine
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    • v.24 no.2
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    • pp.119-145
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    • 2023
  • The Pharmaceutical Affairs Act stipulates medication counseling as an obligatory requirement in the case of preparation of medicine. In fact, there are many cases where pharmacists only tell patients the dose and time and do not properly guide them on taking medications. However, in light of the current situation where non-face-to-face treatment is being attempted, there is a high possibility of drug-taking accidents due to insufficient medication guidance. In addition, as an aging society progresses, the need for explanations on pharmaceuticals is increasing. If a pharmacist causes damage to a patient by failing to give appropriate medication guidance, the patient can claim compensation for damages. In addition, if a drug accident occurs due to a conflict between the pharmacist's duty to guide medication and the doctor's duty to explain, a joint tort is established between the pharmacist and the doctor. Nevertheless, there are cases in which only doctors are judged to bear the tort liability. However, the Pharmaceutical Affairs Act includes providing information for the selection of over-the-counter drugs in the medication guidance as part of the medication guidance obligation. Therefore, in order to reconsider the importance of the medication-taking guidance duty, it is necessary to define the medicationaking information provision method and the medication-taking guidance duty as separate concepts. In addition, it is necessary to amend related regulations centered on patients so that medication guidance, such as side effects of medicines and interactions with concomitant medications, can be made in detail.

The Range of Guarantee Responsibility by an Issuing Bank of Letter of Guarantee under Mixed Settlement Method (혼합결제방식에서 수입화물선취보증서 발행은행의 보증책임 범위)

  • Lee, Jung-Sun;Kim, Cheol-Ho
    • Korea Trade Review
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    • v.41 no.2
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    • pp.231-250
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    • 2016
  • The study attempts to consider L/G(Letter of Guarantee) in a different angle, which is internationally used as a way of commercial customs and practices in a case when the consignee wants to receive the goods without the original Bill of Lading, Thus, this study focuses more on verifying the usage of L/G in Mixed Payment System and the range of guarantee responsibility by an issuing bank through case analysis. This case uses a mixed payment method of L/C(Letter of Credit) and T/T(Telegraphic Transfer) in the transaction of goods. The issuing bank of L/C issues L/G with the amount of L/C which is the same as the amount as C/I(Commercial Invoice). However the carrier deliver all goods laden under both L/C and T/T payment with the production of L/G. In this case, because the buyer is unable to pay, the seller makes a claim for damages to the carrier that the carrier delivers the goods to the buyer against L/G. Finally, the judge gives a decision that the issuing bank of L/G should pay the whole amount of the goods. In this case, the main issue of the dispute is the range of guarantee responsibility by the issuing bank of L/G. As a result of the case analysis, the study suggests two counter strategies for smooth utilization in international trade environment. First, in the case of mixed payment system, a seller should issue a commercial invoice separately based on the amount of each settlement plan in order to clarify the liability of guarantee. Second, banks should establish a new form for L/G including a sentence for verifying liabilities of the bank's side in the current form of L/G.

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An Examination of the Effectiveness of Crisis Response Strategies for Repairing Competence and Integrity Violations

  • Sung, Yen-yi;Lee, Han-joon;Park, Jong-chul
    • Asia Marketing Journal
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    • v.15 no.1
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    • pp.129-154
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    • 2013
  • Product-harm crises, which are connected to defective or dangerous products, are perceived as the most common threats to a company. Product harm crises can distort long standing favorable equality perceptions, tarnish a company's reputation, cause major revenue and market-share losses, lead to costly product recalls, and devastate a carefully nurtured brand equity. However, in spite of the devastating impact of product-harm crises, little systematic research exists to asses its marketing consequences. So, the purpose of this study is to investigate how Koreans react to the crisis response in the aftermath of different crises(competence violation vs. integrity violation) and inspire additional research in crisis communication. This study has three main findings which run counter to the assumptions of Kim et al.(2007). Namely, the current study expands on the research of Kim et al. (2004, 2007) by examining how companies repair customers' trust and corporate attitude after crises. Different from previous studies, this study assumes that apology for an integrity-based crisis is the most appropriate way to repair consumer trust and corporate attitude. As for competence-based crisis, similarly, apology for competence-based crisis can be more successful repairing consumer trust and corporate attitude. Concerning silence strategy, remaining silent dose not admit or deny guilt right away, but instead of asking the perceiver to withhold judgment, suggesting that, silence could be expected to be superior to apology but inferior to denial. Finally, apology for competence violation will be expected to bemore effective than apology for integrity violation. Research conceptual model was as follows: According to the results, apology is found to be the most effective strategy to repair corporate attitude no matter the crisis is perceived as a violation of competence or integrity. Second, company may consider keeping silent as a desirable response because they does not admit nor deny responsibility but ask the public to withhold judgment. However, the result of this study shows that, in the overall crisis situations, silence strategy did not differ significantly from the denial strategy, which suggested that the public wants explanation instead of uncertainty. Third, there was the interaction effect between crisis type and crisis response strategies. In this study, apology is more effective for the competence violated situation in terms of regaining consumer trust and repairing their attitude toward company, while the apology's effectiveness is lower for the integrity-violated situation. More specifically, when the crisis is perceived due to company's lack of ability(competence violation), consumer's trust belief and attitude toward the company is more easily to repair when the company issued a sincere apology. Damaged product is perceived less intentional so participants are more likely to give the company second chance when they apology to the public. By contrast, exaggerated advertisement(integrity violation) is perceived intentionally and thus makes participants angrier toward the accused company. Although apology is perceived as the most effective strategy, when issuing apology, it also means the company admitted their intention. Therefore, in this kind of crisis situation, trust repair needs not only a sincere apology but additional efforts.

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Proposals for Revising the Occupational Exposure Limits for Aluminum in Korea (국내 알루미늄 노출실태 및 노출기준 개정 제안)

  • Seung Won Kim;Young Gyu Phee;Yong-Joon Baek;Taejin Chung;Hye-Sil Lee
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.34 no.1
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    • pp.85-97
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    • 2024
  • Objectives: This study was intended to investigate the revision status of the occupational exposure standards for aluminum at home and abroad; to investigate worker exposure at domestic aluminum manufacturing and handling workplaces; to conduct social and economic evaluation for the revision of domestic aluminum exposure limits. Methods: We investigated the current status of occupational exposure limits for aluminum at home and abroad, and analyzed supporting data. An exposure survey was conducted targeting domestic aluminum manufacturing and handling workplaces. Based on these, revised aluminum occupational exposure limits were proposed. Results: The major aluminum exposure limits at home and abroad show a notable difference. The toxicity of aluminum, which was revealed through animal experiments and epidemiological investigations. The average concentration of aluminum in the air at 12 workplaces was 0.016 mg/m3, and the maximum was 0.0776 mg/m3. When total dust and respiratory dust were measured side by side and simultaneously for the same process, 12.1% of the total mass concentration of aluminum dust was respiratory dust. As a result of measuring and comparing the size distribution of dust with an optical particle counter in real time, 48.1% of the total dust in the form of welding fume and pyro-powder was respiratory dust. Based on the literature review and workplace survey, three proposals for changing the aluminum exposure limit were proposed. Proposal (1): For all types, 10 mg/m3 is unified as the exposure limit except for soluble salts and alkyls. Proposal (2): 1(R) mg/m3 as the exposure limit for all forms except soluble salts and alkyl. Proposal (3): 1(R) mg/m3 for pyro-powder and welding fume, and 10 mg/m3 for metal dust, aluminum oxide, and insoluble compounds as exposure standards. A pyro-powder was defined as dry aluminum powder of 200 mesh size (74 ㎛) or smaller (larger size classified as metal dust). Reason for setting: In the workplace survey, the ratio of respiratory dust to total dust was analyzed to be about 1:10, so it was judged that the domestic standard and the ACGIH standard were compatible. Conclusions: In all scenarios according to the revision of the exposure standard, the B/C ratio was greater than 1 or only benefits existed, so it was evaluated as sufficiently reasonable as a result of the socio-economic evaluation.

Investigation of conservation state on the waxed volumes of annals of the Joseon Dynasty (조선왕조실록 밀납본의 보존상태 조사)

  • Jeong, So-Young;Lee, Hye-Yun;Chung, Yong-Jae;Hong, Jung-Ki;Eom, Doo-Sung
    • 보존과학연구
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    • s.25
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    • pp.119-132
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    • 2004
  • Annals of the Joseon Dynasty is the authentic record of the historical facts and events taken place throughout the entire period of 472 years(25 generations, 1392~1863)described in a chronological order. The tremendous volume of the records contains the factual events taken place in almost all the fields of the Joseon Dynasty ranging from politics, economy to history of the dynasty. Not only because of its affluent contents but also with the precision of its records, it was designated as the National Treasure No. 151 in1973 by the Korean government and also registered as the Memory of the World by UNESCO in October 1997.This study is to report a exhaustive investigation results on the conservation state of annals of the Joseon Dynasty, especially Mt. Jeongjoksan edition, under the storage of the Kyujanggak in order to obtain the current condition, and thereby to estimate the any deterioration of the waxed volumes in the future. According to results of the investigation, we are going to verify damage causes of annals of the Joseon Dynasty, and to consider scientific conservation methods for the permanent preservation of invaluable cultural heritage. The major problem with the preservation of annals has arisen particularly from the deterioration of the waxed volumes of the Mt. Jeongjoksan edition. In order to provide for the counter measures for this problem, we have conducted twice investigations(first :1998~1999, second : 2003) to the internal and external conditions of waxed volumes(Annals of King Taejo~Annals of King Myeongjong).The result of the investigation has indicated that the paper quality of the some of the waxed volumes (Annals of King Taejong~Annals of King Sejong) is cracked and folded and the pages are imbedded to each other due to the hardened or congealed wax on the paper. Some of the pages are even getting moldy. And in order to detect as to whether“ there has been any deterioration progressed to the waxed books in the modern storage facility of the Kyujanggak equipped with constant temperature and humidity condition, the first investigation(1998~1999) and the second investigation(2003) have recorded the values of acidity, whiteness and moisture rate of the waxed paper, reporting an observation that there has been no difference on the measuring items. This indicates that no virtual deterioration has been progressed so far to the waxed volumes preserved in the Kyujanggak. Also, except for the causes of deterioration to the paper by insects and microorganisms, the major cause for the paper damage seems to the change of moisture of the paper caused from the alteration of the temperature and humidity of the storage environment. With this understanding in mind, we have conducted an environmental investigation on the three selected points of the storage in the aspects of the temperature, humidity, air current, $CO_2$,HCHO, and $SO_2$.It has been observed that the temperature stood at $16.9^{\circ}C~20.2^{\circ}C$ and the humidity was stable between 53%~56% during the period of the investigation. The concentration of the carbon monoxide and carbon dioxide of the storage were very similar to those in the air. These data lead to presume that there is no problem in the aspect of carbon oxidization. But the concentration of sulfur dioxide, hydrogen sulfide and formaldehyde of the storage were detected a little higher than those of standard. Therefore, we consider that it is necessary to ventilate the internal air of the store room by means of operating air purification devices.

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The Competition Policy and Major Industrial Policy-Making in the 1980's (1980년대 주요산업정책(主要産業政策) 결정(決定)과 경쟁정책(競爭政策): 역할(役割)과 한계(限界))

  • Choi, Jong-won
    • KDI Journal of Economic Policy
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    • v.13 no.2
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    • pp.97-127
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    • 1991
  • This paper investigates the roles and the limitations of the Korean antitrust agencies-the Office of Fair Trade (OFT) and the Fair Trade Commission (FTC) during the making of the major industrial policies of the 1980's. The Korean antitrust agencies played only a minimal role in three major industrial policy-making issues in the 1980's- the enactment of the Industrial Development Act (IDA), the Industrial Rationalization Measures according to the IDA, and the Industrial Readjustment Measures on Consolidation of Large Insolvent Enterprises based on the revised Tax Exemption and Reduction Control Act. As causes for this performance bias in the Korean antitrust system, this paper considers five factors according to the current literature on implementation failure: ambiguous and insufficient statutory provisions of the Monopoly Regulation and Fair Trade Act (MRFTA); lack of resources; biased attitudes and motivations of the staff of the OFT and the FTC; bureaucratic incapability; and widespread misunderstanding about the roles and functions of the antitrust system in Korea. Among these five factors, bureaucratic incompetence and lack of understanding in various policy implementation environments about the roles and functions of the antitrust system have been regarded as the most important ones. Most staff members did not have enough educational training during their school years to engage in antitrust and fair trade policy-making. Furthermore, the high rate of staff turnover due to a mandatory personnel transfer system has prohibited the accumulation of knowledge and skills required for pursuing complicated structural antitrust enforcement. The limited capability of the OFT has put the agency in a disadvantaged position in negotiating with other economic ministries. The OFT has not provided plausible counter-arguments based on sound economic theories against other economic ministries' intensive market interventions in the name of rationalization and readjustment of industries. If the staff members of antitrust agencies have lacked substantive understanding of the antitrust and fair trade policy, the rest of government agencies must have had serious problems in understanding the correst roles and functions of the antitrust system. The policy environment of the Korean antitrust system, including other economic ministries, the Deputy Prime Minister, and President Chun, have tended to conceptualize the OFT more as an agency aiming only at fair trade policy and less as an agency that should enforce structural monopoly regulation as well. Based on this assessment of the performance of the Korean antitrust system, this paper evaluate current reform proposals for the MRFT A. The inclusion of the regulation of conglomerate mergers and of business divestiture orders may be a desirable revision, giving the MRFTA more complete provisions. However, given deficient staff experties and the unfavorable policy environments, it would be too optimistic and naive to expect that the inclusion of these provisions alone could improve the performance of the Korean antitrust system. In its conclusion, this paper suggests several policy recommendations for the Korean antitrust system, which would secure the stable development and accumulation of antitrust expertise for its staff members and enough understanding and conformity from its environments about its antitrust goals and functions.

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