• Journal of the Korea Society for Simulation
• /
• v.28 no.2
• /
• pp.1-14
• /
• 2019

A full scale hydrodynamic simulation that requires an accurate reproduction of shock-induced detonation was conducted for design of an energetic component system. A detailed hydrodynamic analysis SW was developed to validate the reactive flow model for predicting the shock propagation in a train configuration and to quantify the shock sensitivity of the energetic materials. The pyrotechnic device is composed of four main components, namely a donor unit (HNS+HMX), a bulkhead (STS), an acceptor explosive (RDX), and a propellant (BPN) for gas generation. The pressurized gases generated from the burning propellant were purged into a 10 cc release chamber for study of the inherent oscillatory flow induced by the interferences between shock and rarefaction waves. The pressure fluctuations measured from experiment and calculation were investigated to further validate the peculiar peak at specific characteristic frequency (${\omega}_c=8.3kHz$). In this paper, a step-by-step numerical description of detonation of high explosive components, deflagration of propellant component, and deformation of metal component is given in order to facilitate the proper implementation of the outlined formulation into a shock physics code for a full scale hydrodynamic simulation of the energetic component system.

• Korean Journal of Environmental Biology
• /
• v.38 no.4
• /
• pp.691-704
• /
• 2020

The Ministry of Oceans and Fisheries has designated 17 species as harmful marine organisms with the purpose of managing harmful marine species that threaten health and property. In designating and managing harmful marine species, detailed and effective regulations were originally established in November 2015, and a minor amendment of the directive was published in 2019 - Directive on Designating and Managing Marine Ecosystem Invasive Species and Harmful Marine Species (hereinafter, the Directive). Thus, this study had two aims: Firstly, to increase public awareness of the harmful marine species management system run by the Ministry of Oceans and Fisheries via description of the present harmful marine species risk assessment system. Secondly, to improve the current risk assessment system by providing policy suggestions developed through review of the present harmful marine species designation and management system. In so doing, this study reviewed the 'harmful marine species - harmfulness risk assessment system' in both the definitions of "risk" and "assessment". As a result, the present definition of 'risk' adequately fulfills the policy aims on the Regulation of Marine Ecosystem, which includes an economic value. However, it seems that there is a loophole in the rules of risk assessment, lacking terms of reference in the definition of "risk". Moreover, with regards to risk assessment, a quantitative risk assessment system was sufficient but lacked elements of qualitative risk, suggesting future research in this area may prove useful in the management of harmful marine species.

• Journal of the Korean earth science society
• /
• v.44 no.2
• /
• pp.148-160
• /
• 2023

The Pliny Letter, the first historical record of volcanic eruptions and disasters on Earth, was studied to better understand the Vesuvius' eruption patterns in 79 AD. The two-day eruption, which began at 1 a.m. on August 24th 79 AD, produced large amounts of volcanic ash and pumice, which were carried by the wind and fell on nearby cities. Furthermore, during the eruption, fast-moving pyroclastic flows flowed down the volcano's sides, and several phenomena such as earthquakes and tsunamis occurred. Cities near Mount Vesuvius were buried and destroyed by volcanic ash and pyroclastic flows. Previous studies were collected, analyzed, and investigated and the scope of damage was chosen from Pompeii, Herculaneum, Stabiae, and Oplontis. The sedimentary stratigraphy and thickness vary according to location and distance from Vesuvius in each region. Within the depositional layers, the remains of residents who died during the eruption were also discovered, and 1,150 remains have been discovered in Pompeii, 306 in Herculaneum, 111 in Stabiae, and 54 in Oplontis, but the exact number of people who killed is unknown. The eruption that exhibited the pattern seen in AD 79 was named the Plinian eruption after Pliny and classified as a new type of eruption as a result of Pliny's detailed description of the eruption.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.51 no.2
• /
• pp.54-67
• /
• 2023

Mount Tai, with an elevation of 1,532 meters, has a reputation as ''The Most Revered of the Five Sacred Mountains (五嶽獨尊)", despite not being the highest mountain in China. A guidebook is a book or pamphlet that contains an introduction and description of specific activities or facilities, especially detailed and accurate information about scenic spots, which provide superior vistas to than other commercially publicized locations. The study aims to investigate Mount Tai's landscape characteristics by analyzing the landscape types and elements, the Kernel Density, the Mean Center and the Standard Deviational Ellipse of the landscape elements appearing in guidebooks introducing Mount Tai. The research results of this study are summarized as follows. First, the landscape type characteristics of Mount Tai are dominated by natural landscapes, which are different from what was shown highlighted in poems and Big Data as they proposed that the landscape characteristics of Mount Tai is dominated by human activities. Second, from the perspective of subdivided landscape types, the landscape elements that appeared in Mount Tai are topography, structure, architecture, plants, semantics, human beings and image orderly, based on the proportion of landscape elements. Third, from the perspective of landscape elements by times series, "Fengshan (封禅)", "sacrifices (祭祀)" and "legends" mostly appeared in the 1950s and 1980s, and after the 1990s, "climbing" and "overlooking" mostly appeared. Fourth, the landscape elements of Mount Tai are concentrated in Daiding (岱顶) and Dai Temple (岱庙) in all periods in terms of spatial distribution. This will become an important space for Mount Tai scenic spots in the future. Moreover, as a whole, the landscape elements of Mount Tai have changed from the concentrated distribution form in Mount Tai scenic spot to the scattered distribution form including Mount Tai and Tai'an City. This will provide necessary enlightenment for the landscape preservation and the re-production of guidebooks of Mount Tai scenic spot in the future.

• The Journal of the Korea Contents Association
• /
• v.22 no.5
• /
• pp.110-124
• /
• 2022

The purpose of this study is to develop community design evaluation factors for sustainable urban regeneration and to suggest considerations for sustainable community design by analyzing excellent community design cases. Through literature review, previous studies on the concept and core items of sustainable urban regeneration, and the concept and components of community design were considered. In addition, evaluation indicators for sustainable community design were developed in the socio-economic, physical, environmental, historical and cultural dimensions through the analysis of the linkage with the evaluation factors of community design through the analysis of previous studies. The evaluation index consists of 3 evaluation items and 9 items including social performance and participation at the social level, economic feasibility at the economic level, environmental characteristics at the physical and environmental level, accessibility, contextuality, locality at the historical and cultural level, identity, and artistry. Includes dog evaluation factors. Reliability and effectiveness are secured through the developed evaluation index and detailed description and expert verification. Exploratory factor analysis and expert interviews were conducted through the survey, and as a result of the analysis, the stability and Cronbach'α coefficients were verified, and the validity of the community design evaluation index considering sustainable urban regeneration was recognized through expert interview. The results of this study are considered meaningful in that they can provide basic data for the improvement of community design for sustainable urban regeneration in the future.

• Korean Journal of Culture and Social Issue
• /
• v.18 no.4
• /
• pp.481-503
• /
• 2012

This study aims to investigate the effects of the Big Five Aspects on psychological adjustment and the practical use of the Big Five Aspects in personality studies. Correlations between psychological adjustment(subjective well-being, life satisfaction, anxiety, depression) and the Big Five Aspects were compared to correlations between the Big Five and psychological adjustment. The results showed distinction between two aspects within each of the Big Five that major personality traits that are actually related to psychological adjustment were found. Multiple regressions were used with subjective well-being, life satisfaction, anxiety, and depression as criterion variables to investigate the effect of the Big Five Aspect on psychological adjustment and the results are as followed. Big Five Aspects accounted for 66.2% of the variance in subjective well-being and withdrawal, compassion, industriousness, enthusiasm, assertiveness, openness significantly predicted subjective well-being. Life satisfaction and depression were significantly predicted by withdrawal and enthusiasm. Withdrawal was the only variable that significantly predicted anxiety. Multiple regression also showed that withdrawal and enthusiasm were the most consistent, accountable variables in predicting overall psychological adjustment. This findings indicate that individual's personality traits played a significant role in predicting subjective well-being and mental health as consistent with past findings, and that the Big Five Aspects can offer more detailed and specific description than the Big Five can. Finally, the research discusses implications, limitations and suggestions for further studies.

• Annals of Hepato-Biliary-Pancreatic Surgery
• /
• v.28 no.1
• /
• pp.59-69
• /
• 2024

Backgrounds/Aims: Pancreaticoduodenectomy (PD) is the only radical treatment for periampullary malignancies. Superior mesenteric artery (SMA) first approach combined with total meso-pancreas (MP) excision was conducted to improve the oncological results. There has not been any previous research of a technique that combines the SMA first approach and total MP excision with a detailed description of the MP macroscopical shape. Methods: We prospectively assessed 77 patients with periampullary malignancies between October 2020 and March 2022 (18 months). All patients had undergone PD with SMA first approach combined total MP excision. The perioperative indications, clinical data, intra-operative index, R0 resection rate of postoperative pathological specimens (especially mesopancreatic margin), postoperative complications, and follow-up results were evaluated. Results: The median operative time was 289.6 min (178-540 min), the median intraoperative blood loss was 209 mL (30-1,600 mL). Microscopically, there were 19 (24.7%) cases with metastatic MP, and five cases (6.5%) with R1-resection of the MP. The number of lymph nodes (LNs) harvested and metastatic LNs were 27.2 (maximum was 74) and 1.8 (maximum was 16), respectively. Some (46.8%) patients had pancreatic fistula, but mostly in grade A, with 7 patients (9.1%) who required re-operations. Some 18.2% of cases developed postoperative refractory diarrhea. The rate of in-hospital mortality was 1.3%. Conclusions: The PD with SMA first approach combined TMpE for periampullary malignancies was effective in achieving superior oncological statistics (rate of MP R0-resection and number of total resected LNs) with non-inferior short-term outcomes. It is necessary to evaluate survival outcomes with long-term follow-up.

• The Journal of Internal Korean Medicine
• /
• v.31 no.4
• /
• pp.792-812
• /
• 2010

In the 18th century, Xu Lingtai (徐靈胎) and Yoshimasu Todo (吉益東洞) were famous doctors advocating ancient medicine, though they lived in different countries, China and Japan. We compared their major books, analyzed their academic thoughts and then took conclusions as below. 1. The first, for instance "Classified Prescriptions of Treatise on Cold Damage Diseases, 傷寒論類方" and "Classified Assemblage of Prescriptions, 類聚方". Based on essential thought that a prescription and a syndrome should correspond, these books arranged and classified the Zhang Zhongjing (張仲景)'s texts."Classified Prescriptions of Treatise on Cold Damage Diseases", based on the thought that principles, methods, formulas and medicinals (理法方藥) were integrated in prescriptions, tried to find out the implicit treatment rules in prescriptions and syndromes through analyzing "Treatise on Cold Damage Diseases, 傷寒論". On the other hand, because Classified Assemblage of Prescriptions focused on the syndromes of ancient prescriptions (古方), it classified and collected the related texts of Treatise on Cold Damage Diseases and "Synopsis of Prescriptions of the Golden Chamber, 금궤요략", and then suggested only simple instructions on how to prescribe medicine. So in this book, the trend of experience was clear. 2. The second, there is "100 Kinds Records from Shennong's Classic of Materia Medica, 神農本草經百種錄" and "Description work of herbal pharmacology comprised of excerpts from Shanhanlun and medical experiences, 藥徵". Though both of these books are professional oriental pharmacology publications that advocate reactionism, there were remarkable differences in writing style between them. "Description work of herbal pharmacology comprised of excerpts from Shanhanlun and medical experiences" was based on "Treat on Cold Damage Diseases" and "Synopsis of Prescriptions of the Golden Chamber", just explained the effects of medications and discussed 'matter of course (所當然)', but not discussed 'the reason why (所以然)'. In explaining style of syndromes, it confirmed through research, and emphasized the inductive method. On the other hand, "100 Kinds Records from Shennong's Classic of Materia Medica based on "Shennong's Classic of Materia Medica, 神農本草經", explained the nature of medications and discussed 'the reason why (所以然)'. In explaining style of syndromes, it annotated and explained, and emphasized the process of reasoning. 3. The third, there is "Discuss the Headwaters of Medicine, 醫學源流論" and Severance of Medical evils, 醫斷". Aiming the then medical theories fallen in confused state, these books brought order out of chaos, clarified the categories of medical research, and emphasized the scientific method that could put theories into practice and verify them. The difference is that "Severance of Medical Evils" researched only macroscopic viewable clinical phenomena, and even denied the existence of names of diseases and etiological causes. Thus, it emphasized the accumulation of experiences, laid emphasis on "watching and realizing (目認)", and "understand and taking in (解悟)". Discuss the Headwaters of Medicine extremely emphasized the research of 'something not occuring (未然)', that is to say, induced notions of a disease from observing clinical phenomena, furthermore based on these, predicted the 'something not occuring (未然)' and emphasized researching 'the reason why (所以然)'. As regards how they deal with the traditional theories and post-Zhang Zhongjing's medicines, "Severance of Medical evils" took completely denying attitudes. In case of "Discuss the Headwaters of Medicine", it could be used reasonably through specific situation and detailed analysis. Collectively speaking, there were some differences between medical theories of Xu Lingtai and Yoshimasu Todo. Actually, these differences were whether he tried to research the essence of disease, whether he tried to consider it rationally, and how he treated various opinions occurring in the theories of traditional medicine and clinical experience.

• Journal of Korean Home Economics Education Association
• /
• v.23 no.3
• /
• pp.69-90
• /
• 2011

To develop the descriptive evaluation questionnaire with high validity and reliability on the Clothing and Textiles section of the middle school Technology & Hone Economics textbook, apply it to students and analyze its results. We made out a draft for descriptive evaluation questionnaire that was based upon the concrete establishment of the goal and the range of evaluation. We also made a rubric for scoring as well as sample answer-sheets. Finally, we completed a total of twenty three descriptive evaluation questions and we applied it to sixty five 2nd-grade students in two classes in a middle school. Descriptive evaluation questionnaire exhibited the relative high validity on each question. Moreover, three graders gave the same score on each question of descriptive evaluation, suggesting that descriptive evaluation questionnaire has the high inter-grader reliability and the strong correlation. But, low academic achievement was generally observed in the subjects. They had difficulty in describing their knowledge via their own language and drawing up accurate and detailed answers. They recognized the positive aspects of descriptive evaluation questionnaire, but they felt it uncomfortable due to study-burden and description itself. To overcome these limitations, it is required that students should experience various materials related to subject contents in classes as well as textbooks, concentrate themselves on finding solutions for problems, expand their scope, and practice describe them in advance. Therefore, the additional training for description evaluation questionnaire will be necessary for the more efficient and discriminative questionnaire. Also the questionnaire with high validity and reliability should be developed and the aggressive and voluntary participation of teachers will be needed.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.26 no.1
• /
• pp.31-52
• /
• 2024

Considering the significant relationship between a tree's branch structure and physiology, understanding the detailed branch structure is crucial for fields such as species classification, and 3D tree modelling. Recently, terrestrial laser scanning (TLS) and quantitative structure model (QSM) have enhanced the understanding of branch structures by capturing the radius, length, and branching angle of branches. Previous studies examining branch structure with TL S and QSM often relied on mean or median of branch structure parameters, such as the radius ratio and length ratio in parent-child relationships, as representative values. Additionally, these studies have typically focused on the relationship between trunk and the first order branches. This study aims to explore the distribution of branch structure parameters up to the third order in Aesculus hippocastanum, Ginkgo biloba, and Prunus yedoensis. The gamma distribution best represented the distributions of branch structure parameters, as evidenced by the average of Kolmogorov-Smirnov statistics (radius = 0.048; length = 0.061; angle = 0.050). Comparisons of the mode, mean, and median were conducted to determine the most representative measure indicating the central tendency of branch structure parameters. The estimated distributions showed differences between the mode and mean (average of normalized differences for radius ratio = 11.2%; length ratio = 17.0%; branching angle = 8.2%), and between the mode and median (radius ratio = 7.5%; length ratio = 11.5%; branching angle = 5.5%). Comparisons of the estimated distributions across branch orders and species were conducted, showing variations across branch orders and species. This study suggests that examining the estimated distribution of the branch structure parameter offers a more detailed description of branch structure, capturing the central tendencies of branch structure parameters. We also emphasize the importance of examining higher branch orders to gain a comprehensive understanding of branch structure, highlighting the differences across branch orders.