• Title/Summary/Keyword: value at risk

Search Result 961, Processing Time 0.034 seconds

Exposure Assessment of Heavy Metals Migrated from Glassware on the Korean Market (국내 유통 식품용 유리제의 중금속 노출 평가)

  • Kim, Eunbee;Hwang, Joung Boon;Lee, Jung Eun;Choi, Jae Chun;Park, Se-Jong;Lee, Jong Kwon
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.28 no.1
    • /
    • pp.15-21
    • /
    • 2022
  • The purpose of our study was to investigate the migration level of lead (Pb), cadmium (Cd), and barium (Ba) from glassware into a food simulant and to evaluate the exposure of each element. The test articles were glassware, including tableware, pots, and other containers. Pb, Cd, and Ba were analysed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The analytical performance of the method was validated in terms of its linearity, limit of detection (LOD), limit of quantification (LOQ), recovery, precision, and uncertainty. The monitoring was performed for 110 samples such as glass cups, containers, pots, and bottles. a food simulant. Migration test was conducted at 25? for 24 hours in a dark place using 4% acetic acid as a food simulant. Based on the data; exposure assessment was carried out to compare the estimated daily intake (EDI) to the human safety criteria. The risk levels of Pb and Ba determined in this study were approximately 1.9% and 0.3% of the provisional tolerable weekly intake (PTWI) and tolerable daily intake (TDI) value, respectively, thereby indicating a low exposure to the population.

A Study on Flood Susceptibility of Heritage Sites by Heritage Type Depending on Locational Characteristics (입지특성에 따른 문화재 유형별 홍수 민감성 기초연구)

  • Kim, Ji-Soo
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.40 no.3
    • /
    • pp.46-56
    • /
    • 2022
  • This study aimed to analyze the locational characteristics of heritage sites in Seoul in order to identify flood susceptibility by type. As for the location factors related to flood susceptibility, elevation, slope, distance to streams, and topographic location were analyzed. Literature review was supplemented for the historical and humanistic environments of heritage sites. The results of the study are as follows. First, heritage sites in Seoul are distributed throughout the city, and are especially highly dense in the Hanyangdoseong fortress. It was also confirmed that heritage sites were concentrated around Jung-gu, Jongno-gu, Jingwan-dong, and Ui-dong in the quantitative spatial analyses. Second, types of heritage sites at the circumstance susceptible to flood damage were related to commerce and distribution, traffic, modern traffic and communication, geological monument, residence, government office, and palace. Third, heritage types with locational characteristics that showed low flood susceptibility were found to be natural scenic spots, telecommunication, ceramics, Buddhism, tombs, and tomb sculptural heritage assets. In a time when risk factors that can damage the value of heritage are gradually increasing due to anthropogenic influences along with changes in the natural environment, this study provides basic data for vulnerability analysis that reflects the unique characteristics of heritage assets. The results can contribute to more comprehensive and comprehensive insights for the management and protection of heritage by including the humanities and social science data together with natural factors in the analysis.

Performance Comparison of Reinforcement Learning Algorithms for Futures Scalping (해외선물 스캘핑을 위한 강화학습 알고리즘의 성능비교)

  • Jung, Deuk-Kyo;Lee, Se-Hun;Kang, Jae-Mo
    • The Journal of the Convergence on Culture Technology
    • /
    • v.8 no.5
    • /
    • pp.697-703
    • /
    • 2022
  • Due to the recent economic downturn caused by Covid-19 and the unstable international situation, many investors are choosing the derivatives market as a means of investment. However, the derivatives market has a greater risk than the stock market, and research on the market of market participants is insufficient. Recently, with the development of artificial intelligence, machine learning has been widely used in the derivatives market. In this paper, reinforcement learning, one of the machine learning techniques, is applied to analyze the scalping technique that trades futures in minutes. The data set consists of 21 attributes using the closing price, moving average line, and Bollinger band indicators of 1 minute and 3 minute data for 6 months by selecting 4 products among futures products traded at trading firm. In the experiment, DNN artificial neural network model and three reinforcement learning algorithms, namely, DQN (Deep Q-Network), A2C (Advantage Actor Critic), and A3C (Asynchronous A2C) were used, and they were trained and verified through learning data set and test data set. For scalping, the agent chooses one of the actions of buying and selling, and the ratio of the portfolio value according to the action result is rewarded. Experiment results show that the energy sector products such as Heating Oil and Crude Oil yield relatively high cumulative returns compared to the index sector products such as Mini Russell 2000 and Hang Seng Index.

Relationship between Ischemia-Modified Albumin and the Healing Period of Amputation Wounds in Patients with Diabetes Mellitus Following Non-traumatic Below-Knee Amputation (당뇨족으로 인한 비외상성 하퇴부 절단 환자에서 시행한 절단부 창상의 치유 기간과 Ischemia-Modified Albumin과의 관계)

  • Si Young Heo;Myoung Jin Lee;Hyeon jun Kim;Sung Bin Byun
    • Journal of Korean Foot and Ankle Society
    • /
    • v.27 no.2
    • /
    • pp.49-54
    • /
    • 2023
  • Purpose: The present study examined the effectiveness of the preoperative ischemia-modified albumin (IMA) levels in predicting the healing period of amputation wounds in patients with diabetes mellitus following a non-traumatic below-knee amputation (BKA). Materials and Methods: This study enrolled 41 diabetic foot ulcer patients who underwent BKA at the authors' hospital diabetic foot center from April 2016 to April 2022. Among the 41 patients, 29 (70.7%) were male and 12 (29.3%) were female. Their mean age was 64.54±11.38 years (41~81 years). The mean follow-up period was 19.48±5.56 weeks (14~48 weeks) after BKA. The patients were divided into two groups (high IMA group and normal IMA group), which evaluated the healing period, wound dehiscence, and revision operation rate using a Fisher's exact test and Mann-Whitney U test. Three orthopedic surgeons performed stump wound evaluation, and they were evaluated as healing when all sutures were fused without oozing. Results: Thirty patients (73.2%) (group A) showed a high level of IMA (median: 91.2 U/mL), and 11 (26.8%) patients (group B) showed a normal range of IMA (median: 82.7 U/mL). In group A, the median period for wound healing took 1.4 weeks longer, which was significant (p=0.001). No statistical relationship was observed between wound dehiscence, revision operation rate, and IMA value. There was no correlation between the other risk factors (estimated glomerular filtration rate, HbA1c) and the wound healing period. Conclusion: Although there was a limitation in using IMA as the sole factor to predict the healing period of amputation wounds in patients after BKA, this study revealed a significant positive correlation between IMA and the period of stump healing after BKA. Therefore, the preoperative IMA levels may help predict the period of stump healing after BKA.

A Servicism Model on the New Human and Education System (서비스주의 인간 및 교육 연구)

  • Hyunsoo Kim
    • Journal of Service Research and Studies
    • /
    • v.12 no.3
    • /
    • pp.115-133
    • /
    • 2022
  • This study was conducted to design a new human model and education system for the sustainable life of mankind. Human society is facing a crisis. This study presents a comprehensive plan as the final version of the servicism study. Since the problems of human society are all human problems, research was conducted focusing on the new human and education system. Modern society is markedly different from the existing society in terms of time, space, and humanity, and the leading role of individuals is increased due to the increase in literacy, which can lead to breakdown and ground breaking in an instant. As the value of growth and freedom is increasing, technological innovation is accelerating, and industries and enterprises are growing significantly, so new technologies and industries may put human society at great risk. This study comprehensively diagnosed these problems in the current human society. The problems related to human and education were presented in depth while analyzing and synthesizing the problems presented in the existing servicism studies. The necessary and sufficient conditions for a new system to solve the problems raised were derived. And a system that satisfies these conditions was derived and presented. The new system was named servicism human and education system as a system based on the service philosophy. The structure, operation model, and implementation plan of the new system were presented. The basic structure is a human view that recognizes both reason and irrationality, an education system in which intelligence education and virtue education are balanced, and an education system in which human effort and the values of unwieldy nature are respected. A new education system needs to be put into operation along with the improvement of modern ideology and the compensation system for efforts. Since this study presented a macroscopic direction, further studies are needed to further refine this study.

Existing Population Exposure Assessment Using PM2.5 Concentration and the Geographic Information System (지리정보시스템(GIS) 및 존재인구를 이용한 초미세먼지(PM2.5) 노출평가)

  • Jaemin, Woo;Gihong, Min;Dongjun, Kim;Mansu, Cho;Kyeonghwa, Sung;Jungil, Won;Chaekwan, Lee;Jihun, Shin;Wonho, Yang
    • Journal of Environmental Health Sciences
    • /
    • v.48 no.6
    • /
    • pp.298-305
    • /
    • 2022
  • Background: The concentration of air pollutants as measured by the Air Quality Monitoring System (AQMS) is not an accurate population exposure level since actual human activities and temporal and spatial variability need to be considered. Therefore, to increase the accuracy of exposure assessment, the population should be considered. However, it is difficult to obtain population data due to limitations such as personal information. Objectives: The existing population defined in this study is the number of people in each region's grid. The purpose is to provide a methodology for evaluating exposure to PM2.5 through existing population data provided by the National Geographic Information Institute. Methods: The selected study period was from October 26 to October 28, 2021. Using PM2.5 concentration data measured at the Sensor-based Air Monitoring Station (SAMS) installed in Guro-gu and Wonju-si, the concentration for each grid was estimated by applying inverse distance weights through QGIS version 3.22. Considering the existing population, population-weighted average concentration (PWAC) was calculated and the exposure level of the population was compared by region. Results: The outdoor PM2.5 concentration as measured through the SAMS was high in Wonju-si on all three days. Wonju-si showed an average 22% higher PWAC than Guro-gu. As a result of comparing the PWAC and outdoor PM2.5 concentration by region, the PWAC in Guro-gu was 1~2% higher than the observed value, but it was almost the same. Conversely, observations of Wonju-si were 10.1%, 11.3%, and 8.2% higher than PWAC. Conclusions: It is expected that the Geographic Information System (GIS) method and the existing population will be used to evaluate the exposure level of a population with a narrow activity radius in further research. In addition, based on this study, it is judged that research on exposure to environmental pollutants and risk assessment methods should be expanded.

Analysis of the Effect of Seismic Loads on Residential RC Buildings using the Change in Building Size and Return Period (건물 규모 및 재현주기 변화에 따른 주거용 RC건물에 대한 시공 중 지진하중의 영향 분석)

  • Seong-Hyeon Choi;Jae-Yo Kim
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.36 no.2
    • /
    • pp.85-92
    • /
    • 2023
  • Unlike a completed building, a building under construction may be at risk in terms of safety if a load exceeds the value considered in the design stage owing to various factors, such as a load action different from that in the design stage and insufficient concrete strength. In addition, if an earthquake occurs in a building under construction, greater damage may occur. Therefore, this study studied example models with various sizes of 5, 15, 25, and 60 floors for typical building types and analyzed the effects of seismic load on buildings under construction using construction-stage models according to frame completeness. Because the construction period of the building is much shorter than the period of use after completion, applying same earthquake loads as the design stage to buildings under construction may be excessive. Therefore, earthquakes with a return period of 50 to 2,400 years were applied to the construction stage model to review the seismic loads and analyze the structural performances of the members. Thus, we reviewed whether a load exceeding that of the design stage was applied and the return period level of the earthquake that could ensure structural safety. In addition, assuming the construction period of each example model, the earthquake return period according to the construction period was selected, and the design appropriateness with the selected return period was checked.

Factors Influencing Individual's Intention to Provide MyData: Focusing on the Moderating Effects of Individual Capabilities and Institutional Type (개인의 마이데이터 제공의도에 영향을 미치는 요인: 개인역량과 기관유형의 조절효과를 중심으로)

  • Dong Keun Park;Sung-Byung Yang;Sang-Hyeak Yoon
    • Knowledge Management Research
    • /
    • v.24 no.1
    • /
    • pp.73-97
    • /
    • 2023
  • Recently, the MyData market has been growing as the importance of data and issues related to personal information protection have drawn much attention together. MyData refers to the concept of guaranteeing an individual's right to personal information and providing and utilizing one's data according to individual consent. MyData service providers can combine and analyze customer information to provide personalized services. In the early days, the MyData business was activated mainly by private companies and the financial industry, but recently, public institutions are also actively taking advantage of MyData. Meanwhile, the importance of an individual's intention to provide MyData for the success of MyData businesses continues to increase, but research related to this is lacking. Moreover, existing studies have been mainly conducted on individual benefits of MyData; there are not enough studies in which both public benefit and perceived risk factors are considered at the same time. In this regard, this study intends to derive factors affecting the intention to provide MyData based on the privacy calculus model, examine their influencing mechanism, and further verify the moderating effects of individual capabilities and institutional type. This study can find academic significance in that it expanded and demonstrated the privacy calculus model in the context of MyData providing intention. In addition, the results of this study are expected to offer practical guidelines for developing and managing new services in MyData businesses.

Erosive Effect of Salad Dressing on Flowable Composite Resin Surfaces

  • Na-Hyun Kwon;Im-Hee Jung;Ye-Jin Kim;Jin-Yeong Lee;Na-Sun Jung;Hyun-Woong Jeong;Do-Seon Lim
    • Journal of dental hygiene science
    • /
    • v.23 no.1
    • /
    • pp.29-38
    • /
    • 2023
  • Background: The purpose of this study was to investigate the effect of salad dressings on the flowable composite resin surface and the erosion-inhibitory effect of calcium. Methods: The experiment included six groups: oriental dressing, balsamic dressing, lemon-garlic dressing, lemon-garlic dressing supplemented with 3% calcium, mineral water as a negative control group, and orange juice as a positive control group. pH and titratable acidity were measured. The prepared specimens were immersed in the experimental solutions for 1, 3, 5, 15, and 30 minutes. The surface microhardness was measured using the Vickers hardness number before and after the treatment, and the surface of the specimens was observed using a scanning electron microscope (SEM). Results: The pH values of the experimental groups in increasing order were as follows: lemon-garlic dressing (2.49±0.03), balsamic dressing (3.12±0.06), lemon-garlic dressing +3% calcium (3.27±0.09), oriental dressing (3.75±0.03), orange juice (3.82±0.02), and mineral water (7.32±0.16). The largest surface hardness reduction value was shown in lemon-garlic dressing (-9.61±1.16), followed by balsamic dressing (-9.17±1.63), oriental dressing (-8.62±1.09), orange juice (-8.19±1.36), lemon-garlic dressing +3% calcium (-6.76±1.23), and mineral water (-1.63±2.47). According to the SEM findings, the experimental and positive control groups showed rough surfaces and micropores, whereas the negative control group showed a smooth surface. Moreover, the lemon-garlic dressing with +3% calcium showed fewer micropores and a smoother surface than the lemon-garlic dressing. Conclusion: The intake of salad dressings at a low pH could weaken the surface microhardness of the flowable composite resin. However, adding calcium to these salad dressings can reduce the risk of microhardness reduction on the flowable composite resin surface.

Using Photovoice A Study on the Perception of Death Readiness in Babyboomer Retirees (포토보이스를 활용한 베이비부머 은퇴자의 죽음준비 인식의 연구)

  • Chung, Ju-Young;Lee, Mi-Ran
    • Journal of Convergence for Information Technology
    • /
    • v.12 no.3
    • /
    • pp.171-177
    • /
    • 2022
  • The retirement of the Korean baby boomer generation has become a major factor in an aging society as a large proportion of the population has moved from the middle-aged to the elderly. In addition, after being busy working at a structured workplace for over 30 years, after retirement, they could not adapt to the unstructured environment, causing depression and leading to social problems such as the risk of suicide. research was needed. This study uses photovoice to in-depth research on the research question of how retirees' perception of death preparation, who wants to live a life prepared until death, is used. This is the purpose of this study. The study participants were 7 baby boomer retirees, the data were collected for 2 months, and the perception derived as a result of analyzing the photos, explanations, and in-depth interviews taken by the subject analysis method was used to prepare It was a necessity for education. In the discussion of this study, it is urgent to develop a death preparation education program that can help the baby boomer retirees, and I would like to suggest that the cooperation of local organizations in charge of the program is necessary. This study is meaningful in that it presents basic data in preparing social welfare policy measures for the elderly after retirement through the awareness of death preparations of baby boomer retirees.