• Title/Summary/Keyword: region contrast

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Comparative Analysis of Factors Influencing the Hiring of Directors by Major art Museums within Korea, according to Their Geographic Location and in Comparison to Museums Outside Korea (서울, 수도권, 지방 주요 국공립미술관, 해외 주요 미술관 관장들의 전문적 요인과 사회적 조건에 대한 비교·분석)

  • YUN, Kusuk
    • Korean Association of Arts Management
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    • no.55
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    • pp.115-154
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    • 2020
  • This paper examines the professional qualifications of the directors of important public art museums in Korea in comparison to museums outside Korea through analysis of the directors' primary qualifications, including academic background, major, career experience, and study abroad experience, as well as secondary qualifications, including length of tenure, age, gender, and alma mater, which can indirectly the hiring process for directors. The museums examined in this study are separated into three geographical categories - 1. Seoul, 2. the Seoul Metropolitan Area, and 3. locations in Korea outside the Seoul Metropolitan Area - to analyze how the influence of primary and secondary qualifications differs across geographies. Additionally, this study looks at how the professional qualifications of directors in Korea compare to the qualifications of directors outside Korea to identify the idiosyncrasies of the Korean system. It finds that directors in Korea, in general, have a shorter length of tenure, are older, are more likely to be female, and are less likely to be foreign than the directors of overseas museums. Experience-wise, directors in Korea often have experience working as art experts, artists, and art professors, but their backgrounds differ depending on the region in which they are working. Although directors in Korea have, across the board, studied abroad and graduated from prestigious universities, there are noticeable differences across the three geographical locations looked at. Notably, in Korea, the proportion of directors who majored in practical skills is high, while in the case of directors overseas, the proportion of those who majored in art history is high. In addition, while a high percentage of directors are graduates of Hongik University regardless of their museum's location, graduates of Seoul University are mainly concentrated in the Seoul and Seoul Metropolitan Areas. Museums outside the Seoul Metropolitan Area, on the other hand, often hire directors who have graduated from a nearby university. These differences mark a contrast between Korean museums and museums overseas, which generally hire directors who have graduated from prestigious universities, regardless of geographical location.

Electrochemical Behavior of Tin and Silver during the Electrorecycling of Pb-free Solder (Sn-Ag-Cu) Waste (폐무연솔더(Sn-Ag-Cu)의 전해재활용 시 주석과 은의 전기화학적 거동 연구)

  • Kim, Min-seuk;Lee, Jae-chun;Kim, Rina;Chung, Kyeong-woo
    • Resources Recycling
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    • v.31 no.3
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    • pp.61-72
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    • 2022
  • We investigated the electrochemical behavior of Sn (93.0 %)-Ag (4.06 %)-Cu (0.89 %) during electrolysis of Pb-free solder waste to recover tin and silver. A thin strip of the solder waste produced by high-temperature melting and casting was used as a working electrode to perform electrochemical analysis. During anodic polarization, the current peak of an active region decreased with an increase in the concentration of sulfuric acid used as an electrolyte. This resulted in the electro-dissolution of the working electrode in the electrolyte (1.0 molL-1 sulfuric acid) for a constant current study. The study revealed that the thickening of an anode slime layer at the working surface continuously increased the electrode potential of the working electrode. At 10 mAcm-2, the dissolution reaction continued for 25 h. By contrast, at 50 mAcm-2, a sharp increase in the electrode potential stopped the dissolution in 2.5 h. During dissolution, silver enrichment in the anode slime reached 94.3% in the 1 molL-1 sulfuric acid electrolyte containing a 0.3 molL-1 chlorine ion, which was 12.7% higher than that without chlorine addition. Moreover, the chlorine enhanced the stability of the dissolved tin ions in the electrolyte as well as the current efficiency of tin electro-deposition at the counter electrode.

Influence of kilovoltage- peak and the metal artifact reduction tool in cone-beam computed tomography on the detection of bone defects around titanium-zirconia and zirconia implants

  • Fontenele, Rocharles Cavalcante;Nascimento, Eduarda Helena Leandro;Imbelloni-Vasconcelos, Ana Catarina;Martins, Luciano Augusto Cano;Pontual, Andrea dos Anjos;Ramos-Perez, Flavia Maria Moraes;Freitas, Deborah Queiroz
    • Imaging Science in Dentistry
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    • v.52 no.3
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    • pp.267-273
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    • 2022
  • Purpose: The aim of this study was to assess the influence of kilovoltage- peak (kVp) and the metal artifact reduction (MAR) tool on the detection of buccal and lingual peri-implant dehiscence in the presence of titanium-zirconia (Ti-Zr) and zirconia (Zr) implants in cone-beam computed tomography (CBCT) images. Materials and Methods: Twenty implant sites were created in the posterior region of human mandibles, including control sites (without dehiscence) and experimental sites (with dehiscence). Individually, a Ti-Zr or Zr implant was placed in each implant site. CBCT scans were performed using a Picasso Trio device, with variation in the kVp setting (70 or 90 kVp) and whether the MAR tool was used. Three oral radiologists scored the detection of dehiscence using a 5-point scale. The area under the receiver operating characteristic (ROC) curve, sensitivity, and specificity were calculated and compared by multi-way analysis of variance (α=0.05). Results: The kVp, cortical plate involved (buccal or lingual cortices), and MAR did not influence any diagnostic values (P>0.05). The material of the implant did not influence the ROC curve values(P>0.05). In contrast, the sensitivity and specificity were statistically significantly influenced by the implant material (P<0.05) with Zr implants showing higher sensitivity values and lower specificity values than Ti-Zr implants. Conclusion: The detection of peri-implant dehiscence was not influenced by kVp, use of the MAR tool, or the cortical plate. Greater sensitivity and lower specificity were shown for the detection of peri-implant dehiscence in the presence of a Zr implant.

Study on Effective Operational Plan of Maritime Safety Enforcement Task : Focus on Vessel Safety Management (해양안전 집행업무의 효율적 운영방안 연구 -선박안전 관리를 중심으로-)

  • Byungdoo Yun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.7
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    • pp.1169-1178
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    • 2022
  • This study examines an effective operational plan of a maritime safety enforcement task that is distributed in the Ministry of Oceans and Fisheries and the Korea Coast Guard for maritime safety. Considering the sinking of the MV Sewol and Seohae vessels and the MV Hebei Spirit oil spill, normally marine safety accidents tend to not only damage human life, property, and marine environment but can also expand to disasters; therefore, precautionary measures are required. However, the Korean government takes superficial efforts in case of large-scale accidents. In case of the MV Sewol ferry, the government only focused on punishing the officials involved as a follow up and never mentioned any effective plan, such as "unification of maritime safety enforcement," in contrast to an advanced country. As a result, there are endless major and minor backward accidents. The probability of large-scale maritime accidents and backwardness accidents is increasing owing to vessels becoming large sized, high speed, and aged; sailors being unqualified; port traffic increase, development of marine leisure; and inefficiency dual marine safety systems. Therefore, based on the review of previous studies related to maritime safety, major advanced country's cases, and unified case of the vessel traffic service, this study suggests effective methods such as coastal vessel safety management, port state control and aid to navigation management, which are directly connected with maritime safety.

Whose Science is More Scientific? The Role of Science in WTO Trade Disputes

  • Kim, Inkyoung;Brazil, Steve
    • Analyses & Alternatives
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    • v.2 no.1
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    • pp.31-69
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    • 2018
  • This study examines the role of science in resolving trade disputes. After the Great East Japan Earthquake of 11 March 2011 that not only jeopardized the people of Japan, but also put the safety of an entire region at risk, the Republic of Korea (Korea) has imposed import bans as well as increased testing and certification requirements for radioactive material on Japanese food products. Japan has challenged these restrictions at the World Trade Organizations Dispute Settlement Body (DSB). This study aims to explain how international trade agreements and previous DSB rulings have dealt with different scientific viewpoints provided by confronting parties. In doing so, it will contrast the viewpoints espoused by Korean and Japanese representatives, and then analyzes the most similar case studies previously ruled on by the DSB, including the case of beef hormones and the case of genetically modified crops including biotech corn, both between the United States and the European Communities (EC). This study finds that science is largely subordinate to national interests in the case of state decision-making within the dispute settlement processes, and science has largely been relegated to a supportive role. Due to the ambiguity and lack of truly decisive decisions in the Appellate Body in science-based trade disputes, this study concludes that the Appellate Body avoids taking a firm scientific position in cases where science is still inconclusive in any capacity. Due to the panel's unwillingness to establish expert review boards as it has the power to do, instead favoring an individual-based system so that all viewpoints can be heard, it has also developed a system with its own unique weaknesses. Similar to any court of law in which each opposing party defends its own interests, each side brings whatever scientific evidence it can to defend its position, incentivizing them to disregard scientific conclusions unfavorable to their position. With so many questions that can arise, combined with the problems of evolving science, questions of risk, and social concerns in democratic society, it is no wonder that the panel views scientific information provided by the experts as secondary to the legal and procedural issues. Despite being ruled against the EC on legal issues in two previous cases, the EC essentially won both times because the panel did not address whether its science was correct or not. This failure to conclusively resolve a debate over whose science is more scientific enabled the EC to simply fix the procedural issues, while continuing to enforce trade restrictions based on their scientific evidence. Based on the analysis of the two cases of disputes, Korea may also find itself guilty of imposing an unwarranted moratorium on Japan's fish exports, only to subsequently pass new restrictions on labelling and certification requirements because Japan may have much scientific evidence at its disposal. However, Korea might be able to create enough uncertainty in the panel to force them to rule exclusively on the legal issues of the case. This will then equip Korea, like the EC in the past, with a way of working around the ruling, by changing whatever legal procedure they need to while maintaining some, if not most, of its restrictions when the panel fails to address its case on scientific grounds.

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Cultivation of millet in Mahan-Baekje Villages: Archaeobotanical examination of Osan site, Jangheung, Korea (전남 마한백제계 취락의 서속(黍粟) 재배와 농경 체계: 장흥 봉림리 오산유적 자료를 중심으로)

  • RYU Ara;KIM Sebin;OH Byungwook;KIM Minkoo
    • Korean Journal of Heritage: History & Science
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    • v.56 no.2
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    • pp.48-60
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    • 2023
  • Although foxtail and broomcorn millet have been cultivated since the Neolithic Age on the Korean Peninsula, there have been few studies on how the importance of millet cultivation changed over time. The discovery of millet has been rare in the Mahan-Baekje villages in the Jeonnam region, and archaeological discussions on ancient farming have centered around rice farming. However, a large amount of millet was found at the Osan site in Bongrim-ri, Jangheung, showing that the tradition of millet cultivation continued during the AD 3-4 centuries. In contrast to rice farming, which requires low-lying wetlands, hot and humid summers, and a large labor force, millet cultivation has few restrictions in terms of growing environment and labor mobilization. Regarding harvesting seasons, the crops at the Osan site can be divided into fall harvesting (rice, legumes, millet) and summer harvesting (wheat). Regarding field locations, the crops are divided into wetland crops (rice) and dryland crops (wheat, legumes, millet). The operation of the dual agricultural system contributed to subsistence resilience and agricultural production, making it possible to effectively manage social and climatic crises.

The Estimation of Soil Moisture Index by SWAT Model and Drought Monitoring (SWAT 모형을 이용한 토양수분지수 산정과 가뭄감시)

  • Hwang, Tae Ha;Kim, Byung Sik;Kim, Hung Soo;Seoh, Byung Ha
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4B
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    • pp.345-354
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    • 2006
  • Drought brings on long term damage in contrast to flood, on economic loss in the region, and on ecologic and environmental disruptions. Drought is one of major natural disasters and gives a painful hardship to human beings. So we have tried to quantify the droughts for reducing drought damage and developed the drought indices for drought monitoring and management. The Palmer's drought severity index (PDSI) is widely used for the drought monitoring but it has the disadvanges and limitations in that the PDSI is estimated by considering just climate conditions as pointed out by many researchers. Thus this study uses the SWAT model which can consider soil conditions like soil type and land use in addition to climate conditions. We estimate soil water (SW) and soil moisture index (SMI) by SWAT which is a long term runoff simulation model. We apply the SWAT model to Soyang dam watershed for SMI estimation and compare SMI with PDSI for drought analysis. Say, we calibrate and validate the SWAT model by daily inflows of Soyang dam site and we estimate long term daily soil water. The estimated soil water is used for the computation of SMI based on the soil moisture deficit and we compare SMI with PDSI. As the results, we obtained the determination coefficient of 0.651 which means the SWAT model is applicable for drought monitoring and we can monitor drought in more high resolution by using GIS. So, we suggest that SMI based on the soil moisture deficit can be used for the drought monitoring and management.

Global Trends of In-Situ Resource Utilization (우주 현지자원활용 글로벌 동향 )

  • Dong Young Rew
    • Journal of Space Technology and Applications
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    • v.3 no.3
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    • pp.199-212
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    • 2023
  • In contrast to the short-term nature of lunar missions in the past, lunar missions in new space era aim to extend the presence on the lunar surface and to use this capability for the Mars exploration. In order to realize extended human presence on the Moon, production and use of consumables and fuels required for the habitation and transportation using in-situ resources is an important prerequisite. The Global Exploration Roadmap presented by the International Space Exploration Coordination Group (ISECG), which reflects the space exploration plans of participating countries, shows the phases of progress from lunar surface exploration to Mars exploration and relates in-situ resource utilization (ISRU) capabilities to each phase. Based on the ISRU Gap Assessment Report from the ISECG, ISRU technology is categorized into in-situ propellant and consumable production, in-situ construction, in-space manufacturing, and related areas such as storage and utilization of products, power systems required for resource utilization. Among the lunar resources, leading countries have prioritized the utilization of ice water existing in the permanent shadow region near the lunar poles and the extraction of oxygen from the regolith, and are preparing to investigate the distribution of resources and ice water near the lunar south pole through unmanned landing missions. Resource utilization technologies such as producing hydrogen and oxygen from water by hydroelectrolysis and extracting oxygen from the lunar regolith are being developed and tested in relevant lunar surface analogue environments. It is also observed that each government emphasizes the use and development of the private sector capabilities for sustainable lunar surface exploration by purchasing lunar landing services and providing opportunities to participate in resource exploration and material extraction.

Characteristics of Signal-to-Noise Paradox and Limits of Potential Predictive Skill in the KMA's Climate Prediction System (GloSea) through Ensemble Expansion (기상청 기후예측시스템(GloSea)의 앙상블 확대를 통해 살펴본 신호대잡음의 역설적 특징(Signal-to-Noise Paradox)과 예측 스킬의 한계)

  • Yu-Kyung Hyun;Yeon-Hee Park;Johan Lee;Hee-Sook Ji;Kyung-On Boo
    • Atmosphere
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    • v.34 no.1
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    • pp.55-67
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    • 2024
  • This paper aims to provide a detailed introduction to the concept of the Ratio of Predictable Component (RPC) and the Signal-to-Noise Paradox. Then, we derive insights from them by exploring the paradoxical features by conducting a seasonal and regional analysis through ensemble expansion in KMA's climate prediction system (GloSea). We also provide an explanation of the ensemble generation method, with a specific focus on stochastic physics. Through this study, we can provide the predictability limits of our forecasting system, and find way to enhance it. On a global scale, RPC reaches a value of 1 when the ensemble is expanded to a maximum of 56 members, underlining the significance of ensemble expansion in the climate prediction system. The feature indicating RPC paradoxically exceeding 1 becomes particularly evident in the winter North Atlantic and the summer North Pacific. In the Siberian Continent, predictability is notably low, persisting even as the ensemble size increases. This region, characterized by a low RPC, is considered challenging for making reliable predictions, highlighting the need for further improvement in the model and initialization processes related to land processes. In contrast, the tropical ocean demonstrates robust predictability while maintaining an RPC of 1. Through this study, we have brought to attention the limitations of potential predictability within the climate prediction system, emphasizing the necessity of leveraging predictable signals with high RPC values. We also underscore the importance of continuous efforts aimed at improving models and initializations to overcome these limitations.

Radiological and Geochemical Assessment of Different Rock Types from Ogun State in Southwestern Nigeria

  • Olabamiji Aliu Olayinka;Alausa Shamsideen Kunle
    • Journal of Environmental Health Sciences
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    • v.49 no.5
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    • pp.251-261
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    • 2023
  • Background: This paper deals with the study of natural radioactivity in rocks from Ogun State in Southwestern Nigeria. The aim is to determine radiation emissions from rocks in order to estimate radiation hazard indices. Objectives: The following objectives were targeted: 1. To determine radiation emissions from each type of rocks; 2. To estimate radiation hazard indices based on the rocks; 3. To correlate the activity concentrations of radionuclides with major oxides. Methods: The samples were analyzed using a NaI (Tl) gamma ray spectrometric detector and PerkinElmer AAnalyst 400 AAS spectrometer. Results: The activity of 40K, 226Ra, and 232Th were found in order of decreasing magnitude from pegmatite>granite>migmatite. In contrast, lower concentrations were found in shale, phosphate, clay stone, sandstone and limestone. The mean absorbed doses were 125±23 nGyh-1 (migmatite), 74±13 nGy/h (granite), 72±13 nGyh-1 (pegmatite), 64±09 nGyh-1 (quartzite), 45±16 nGyh-1 (shale), 41±09 nGyh-1 (limestone), 41±11 nGyh-1 (clay stone), 24±03 nGyh-1 (phosphate), and 21±10 nGyh-1 (sandstone). The outdoor effective dose rates in all rock samples were slightly higher than the world average dose value of 0.34 mSvy-1. The percentage composition of SiO2 in the rock samples was above 50 wt% except for in the limestone, shale and phosphate. Al2O3 ranged from 4.10~21.24 wt%, Fe2O3 from 0.39~7.5 wt%, and CaO from 0.09-46.6 wt%. In addition, Na2O and K2O were present in at least 5 wt%. Other major oxides, including TiO2, P2O5, K2O, MnO, MgO and Na2O were depleted. Conclusions: The findings suggest that Ogun State may be described as a region with elevated background radiation. It is recommended that houses should be constructed with good cross ventilation and residences should use home radiation monitoring instruments to monitor radon emanating from walls.