• Title/Summary/Keyword: 최소단위

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Development of a Probabilistic Model for the Estimation of Yearly Workable Wave Condition Period for Offshore Operations - Centering on the Sea off the Ulsan Harbor (해상작업 가능기간 산정을 위한 확률모형 개발 - 울산항 전면 해역을 중심으로)

  • Choi, Se Ho;Cho, Yong Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.3
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    • pp.115-128
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    • 2019
  • In this study, a probabilistic model for the estimation of yearly workable wave condition period for offshore operations is developed. In doing so, we first hindcast the significant wave heights and peak periods off the Ulsan every hour from 2003.1.1 to 2017.12.31 based on the meteorological data by JMA (Japan Meterological Agency) and NOAA (National Oceanic and Atmospheric Administration), and SWAN. Then, we proceed to derive the long term significant wave height distribution from the simulated time series using a least square method. It was shown that the agreements are more remarkable in the distribution in line with the Modified Glukhovskiy Distribution than in the three parameters Weibull distribution which has been preferred in the literature. In an effort to develop a more comprehensive probabilistic model for the estimation of yearly workable wave condition period for offshore operations, wave height distribution over the 15 years with individual waves occurring within the unit simulation period (1 hour) being fully taken into account is also derived based on the Borgman Convolution Integral. It is shown that the coefficients of the Modified Glukhovskiy distribution are $A_p=15.92$, $H_p=4.374m$, ${\kappa}_p=1.824$, and the yearly workable wave condition period for offshore work is estimated to be 319 days when a threshold wave height for offshore work is $H_S=1.5m$. In search of a way to validate the probabilistic model derived in this study, we also carry out the wave by wave analysis of the entire time series of numerically simulated significant wave heights over the 15 years to collect every duration periods of waves the height of which are surpassing the threshold height which has been reported to be $H_S=1.5m$ in the field practice in South Korea. It turns out that the average duration period is 45.5 days from 2003 to 2017, which is very close to 46 days from the probabilistic model derived in this study.

A review on the design requirement of temperature in high-level nuclear waste disposal system: based on bentonite buffer (고준위폐기물처분시스템 설계 제한온도 설정에 관한 기술현황 분석: 벤토나이트 완충재를 중심으로)

  • Kim, Jin-Seop;Cho, Won-Jin;Park, Seunghun;Kim, Geon-Young;Baik, Min-Hoon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.21 no.5
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    • pp.587-609
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    • 2019
  • Short-and long-term stabilities of bentonite, favored material as buffer in geological repositories for high-level waste were reviewed in this paper in addition to alternative design concepts of buffer to mitigate the thermal load from decay heat of SF (Spent Fuel) and further increase the disposal efficiency. It is generally reported that the irreversible changes in structure, hydraulic behavior, and swelling capacity are produced due to temperature increase and vapor flow between $150{\sim}250^{\circ}C$. Provided that the maximum temperature of bentonite is less than $150^{\circ}C$, however, the effects of temperature on the material, structural, and mineralogical stability seems to be minor. The maximum temperature in disposal system will constrain and determine the amount of waste to be disposed per unit area and be regarded as an important design parameter influencing the availability of disposal site. Thus, it is necessary to identify the effects of high temperature on the performance of buffer and allow for the thermal constraint greater than $100^{\circ}C$. In addition, the development of high-performance EBS (Engineered Barrier System) such as composite bentonite buffer mixed with graphite or silica and multi-layered buffer (i.e., highly thermal-conductive layer or insulating layer) should be taken into account to enhance the disposal efficiency in parallel with the development of multilayer repository. This will contribute to increase of reliability and securing the acceptance of the people with regard to a high-level waste disposal.

Analysis of Chlorophyll-a and Algal Bloom Indices using Unmanned Aerial Vehicle based Multispectral Images on Nakdong River (무인항공기 기반 다중분광영상을 이용한 낙동강 Chlorophyll-a 및 녹조발생지수 분석)

  • KIM, Heung-Min;CHOE, Eunyoung;JANG, Seon-Woong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.25 no.1
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    • pp.101-119
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    • 2022
  • Existing algal bloom monitoring is based on field sampling, and there is a limit to understanding the spatial distribution of algal blooms, such as the occurrence and spread of algae, due to local investigations. In this study, algal bloom monitoring was performed using an unmanned aerial vehicle and multispectral sensor, and data on the distribution of algae were provided. For the algal bloom monitoring site, data were acquired from the Mulgeum·Mae-ri site located in the lower part of the Nakdong River, which is the areas with frequent algal bloom. The Chlorophyll-a(Chl-a) value of field-collected samples and the Chl-a estimation formula derived from the correlation between the spectral indices were comparatively analyzed. As a result, among the spectral indices, Maximum Chlorophyll Index (MCI) showed the highest statistical significance(R2=0.91, RMSE=8.1mg/m3). As a result of mapping the distribution of algae by applying MCI to the image of August 05, 2021 with the highest Chl-a concentration, the river area was 1.7km2, the Warning area among the indicators of the algal bloom warning system was 1.03km2(60.56%) and the Algal Bloom area occupied 0.67km2(39.43%). In addition, as a result of calculating the number of occurrence days in the area corresponding to the "Warning" in the images during the study period (July 01, 2021~November 01, 2021), the Chl-a concentration above the "Warning" level was observed in the entire river section from 12 to 19 times. The algal bloom monitoring method proposed in this study can supplement the limitations of the existing algal bloom warning system and can be used to provide information on a point-by-point basis as well as information on a spatial range of the algal bloom warning area.

Success Factor in the K-Pop Music Industry: focusing on the mediated effect of Internet Memes (대중음악 흥행 요인에 대한 연구: 인터넷 밈(Internet Meme)의 매개효과를 중심으로)

  • YuJeong Sim;Minsoo Shin
    • Journal of Service Research and Studies
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    • v.13 no.1
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    • pp.48-62
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    • 2023
  • As seen in the recent K-pop craze, the size and influence of the Korean music industry is growing even bigger. At least 6,000 songs are released a year in the Korean music market, but not many can be said to have been successful. Many studies and attempts are being made to identify the factors that make the hit music. Commercial factors such as media exposure and promotion as well as the quality of music play an important role in the commercial success of music. Recently, there have been many marketing campaigns using Internet memes in the pop music industry, and Internet memes are activities or trends that spread in various forms, such as images and videos, as cultural units that spread among people. Depending on the Internet environment and the characteristics of digital communication, contents are expanded and reproduced in the form of various memes, which causes a greater response to consumers. Previously, the phenomenon of Internet memes has occurred naturally, but artists who are aware of the marketing effects have recently used it as an element of marketing. In this paper, the mediated effect of Internet memes in relation to the success factors of popular music was analyzed, and a prediction model reflecting them was proposed. As a result of the analysis, the factors with the mediated effect of 'cover effect' and 'challenge effect' were the same. Among the internal success factors, there were mediated effects in "Singer Recognition," the genres of "POP, Dance, Ballad, Trot and Electronica," and among the external success factors, mediated effects in "Planning Company Capacity," "The Number of Music Broadcasting Programs," and "The Number of News Articles." Predictive models reflecting cover effects and challenge effects showed F1-score at 0.6889 and 0.7692, respectively. This study is meaningful in that it has collected and analyzed actual chart data and presented commercial directions that can be used in practice, and found that there are many success factors of popular music and the mediating effects of Internet memes.

Study on Tourism Demand Forecast and Influencing Factors in Busan Metropolitan City (부산 연안도시 관광수요 예측과 영향요인에 관한 연구)

  • Kyu Won Hwang;Sung Mo Nam;Ah Reum Jang;Moon Suk Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.7
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    • pp.915-929
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    • 2023
  • Improvements in people's quality of life, diversification of leisure activities, and changes in population structure have led to an increase in the demand for tourism and an expansion of the diversification of tourism activities. In particular, for coastal cities where land and marine tourism elements coexist, various factors influence their tourism demands. Tourism requires the construction of infrastructure and content development according to the demand at the tourist destination. This study aims to improve the prediction accuracy and explore influencing factors through time series analysis of tourism scale using agent-based data. Basic local governments in the Busan area were examined, and the data used were the number of tourists and the amount of tourism consumption on a monthly basis. The univariate time series analysis, which is a deterministic model, was used along with the SARIMAX analysis to identify the influencing factor. The tourism consumption propensity, focusing on the consumption amount according to business types and the amount of mentions on SNS, was set as the influencing factor. The difference in accuracy (RMSE standard) between the time series models that did and did not consider COVID-19 was found to be very wide, ranging from 1.8 times to 32.7 times by region. Additionally, considering the influencing factor, the tourism consumption business type and SNS trends were found to significantly impact the number of tourists and the amount of tourism consumption. Therefore, to predict future demand, external influences as well as the tourists' consumption tendencies and interests in terms of local tourism must be considered. This study aimed to predict future tourism demand in a coastal city such as Busan and identify factors affecting tourism scale, thereby contributing to policy decision-making to prepare tourism demand in consideration of government tourism policies and tourism trends.

Evaluation of the Utilization Potential of High-Resolution Optical Satellite Images in Port Ship Management: A Case Study on Berth Utilization in Busan New Port (고해상도 광학 위성영상의 항만선박관리 활용 가능성 평가: 부산 신항의 선석 활용을 대상으로)

  • Hyunsoo Kim ;Soyeong Jang ;Tae-Ho Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.5_4
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    • pp.1173-1183
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    • 2023
  • Over the past 20 years, Korea's overall import and export cargo volume has increased at an average annual rate of approximately 5.3%. About 99% of the cargo is still being transported by sea. Due to recent increases in maritime cargo volume, congestion in maritime logistics has become challenging due to factors such as the COVID-19 pandemic and conflicts. Continuous monitoring of ports has become crucial. Various ground observation systems and Automatic Identification System (AIS) data have been utilized for monitoring ports and conducting numerous preliminary studies for the efficient operation of container terminals and cargo volume prediction. However, small and developing countries' ports face difficulties in monitoring due to environmental issues and aging infrastructure compared to large ports. Recently, with the increasing utility of artificial satellites, preliminary studies have been conducted using satellite imagery for continuous maritime cargo data collection and establishing ocean monitoring systems in vast and hard-to-reach areas. This study aims to visually detect ships docked at berths in the Busan New Port using high-resolution satellite imagery and quantitatively evaluate berth utilization rates. By utilizing high-resolution satellite imagery from Compact Advanced Satellite 500-1 (CAS500-1), Korea Multi-Purpose satellite-3 (KOMPSAT-3), PlanetScope, and Sentinel-2A, ships docked within the port berths were visually detected. The berth utilization rate was calculated using the total number of ships that could be docked at the berths. The results showed variations in berth utilization rates on June 2, 2022, with values of 0.67, 0.7, and 0.59, indicating fluctuations based on the time of satellite image capture. On June 3, 2022, the value remained at 0.7, signifying a consistent berth utilization rate despite changes in ship types. A higher berth utilization rate indicates active operations at the berth. This information can assist in basic planning for new ship operation schedules, as congested berths can lead to longer waiting times for ships in anchorages, potentially resulting in increased freight rates. The duration of operations at berths can vary from several hours to several days. The results of calculating changes in ships at berths based on differences in satellite image capture times, even with a time difference of 4 minutes and 49 seconds, demonstrated variations in ship presence. With short observation intervals and the utilization of high-resolution satellite imagery, continuous monitoring within ports can be achieved. Additionally, utilizing satellite imagery to monitor changes in ships at berths in minute increments could prove useful for small and developing country ports where harbor management is not well-established, offering valuable insights and solutions.

Suggestions on Expanding Admission Number of Medical School (의과대학 정원 확대에 대한 제언)

  • Eun-Cheol Park
    • Health Policy and Management
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    • v.34 no.2
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    • pp.120-128
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    • 2024
  • From February to now 2024, there continues to be controversy over the expansion of admission number to medical school. Some of the controversy arises from a mix of present and future time points. In the present time point, the controversy over whether physicians are some shortages or not has various aspects. Some aspects are presented as evidence of the physician shortage and others as non-shortage. Also, the presenting evidence of shortage is being disputed, and so is the evidence of the contrary. This controversy over whether there is a shortage or not in the present time point makes it difficult to reach a consensus. In 10 years, the shortage of doctors will increase due to the rapid increase in the elderly population, so the admission number of medical schools will need to be increased. However, the increase must be such that there is minimal deterioration in the quality of medical education. More admission numbers should be allocated to medical schools with a high quality of medical education. This study suggests that large-scale medical schools increase the admission number by 20%-30%, and small-scale medical schools increase the admission number by 40%-50%, if so, the total increasing number is 760 to 1,066. If the 2,000-person increase is enforced, the quality of medical education must be carefully evaluated and the results should be reflected in adjusting the admission number of medical schools. In 20 years later, the admission number of medical schools will have to be reduced. This is because the physician supply is changing to a linear function and the physician demand (medical care demand) is changing to a quadratic function. Even if the current number is maintained, there will be an excess of doctors from 2048, so the medical school admission number must be reduced and its size will be reduced to about 2,000, a 30% reduction from the current number. Because the same reduction rate for all medical schools will result in many small-scale medical schools, the M&A (mergers and acquisitions) strategy should be considered with 40 medical schools and 12 Korean medical schools. In Korea, the main contributor to estimating physician demand is the change in population structure. Due to the rapid decrease in the total fertility rate, future population projections are uncertain. The recent rapid increase in healthcare utilization should be reexamined in the forecasting of physician demand. Since the various factors that affect the estimate of doctor supply and demand are unclear, the estimate of physician supply and demand must be continuously conducted every five years, and the Health Care Workforce Committee must be established and operated. The effects of increasing the admission number of medical schools should be evaluated and adjusted annually.

CHOBUN, Understanding the Double Burial Custom in Korea from a Jungian Perspective : Focusing on Putrefaction and Reduction to Bones (초분, 한국 이중장제의 분석심리학적 고찰 : 부패와 뼈로의 환원을 중심으로)

  • Jahyeon Cho
    • Sim-seong Yeon-gu
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    • v.31 no.2
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    • pp.113-150
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    • 2016
  • Chobun refers to a temporary grave covered with straw thatch that contains a corpse until its flesh is gone. When all the flesh has rotted away, the straw grave is disassembled and only the bones are retrieved. Therefore, Chobun is an example of a secondary burial custom (German : Doppel Bestattung) that is composed of a first temporary funeral for processing the corpse's flesh, and a second permanent burial of the final remains (bones or ashes). The duration of the temporary burial is determined by the time needed for decomposing the flesh of the deceased. Building a Chobun progresses putrefaction and reduction to bone. In the literature of alchemy, putrefaction and new life occur simultaneously. The purpose of rotting is to make the flesh disappear, leaving only its essence. It is making the physical body enter a spiritual state, so that the dead can enter into a different world. One must endure the unstable rotting process until the smell of flesh has faded. The rotting process is the attitude of accepting the terrible, polluted aspect of the corpse, while maintaining a helpless, passive posture, in order to allow new possibilities. When we try to approach an archetypal aspect of the unconscious, it is often experienced in threatening, aggressive ways. In the individuation process, the unconscious offers us the blessing of a new spiritual awakening and renewed sense of life, only when we have the courage to see this terrifying and contaminated side of our psyche. This is exactly what putrefaction means. Bone and skeleton symbolize the indestructible, imperishable, and essential elements of life. Bone is the minimum unit and foundation for regeneration, where new life can grow. Reduction to bone is moving back to the origin of life, to the womb. Psychologically, it means discarding one's ego-centeredness and allowing the Self to lead the entire process of individuation. Going through the painful process of reduction to a skeleton for the purpose of further development is a declaration of the death of the ego, aiming at the liberation from perishable flesh and acquisition of the spiritual, regenerative, and immortal elements of life. Chobun also denotes the yearly decay and revival of life, especially of vegetal life. In Chobun, this symbolic meaning of the vegetal cycle of life is emphasized to represent the part of life that survives even after death. Vegetation related to Chobun deals with the continuity of life and psychologically with the Self. Images of vegetation are closely related to the existence of life beyond death, which is the existence of the Self, the source of energy that constantly renews and rejuvenates the consciousness.

Breeding and Development of the Tscherskia triton in Jeju Island (제주도 서식 비단털쥐(Tscherskia triton)의 번식과 발달)

  • Park, Jun-Ho;Oh, Hong-Shik
    • Korean Journal of Environment and Ecology
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    • v.31 no.2
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    • pp.152-165
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    • 2017
  • The greater long-tail hamster, Tscherskia triton, is widely distributed in Northern China, Korea and adjacent areas of Russia. Except for its distribution, biological characteristics related to life history, behavior, and ecological influences for this species are rarely studied in Korea. This study was conducted to obtain biological information on breeding, growth and development that are basic to species-specific studies. The study adopted laboratory management of a breeding programme for T. triton collected in Jeju Island from March, 2015 to December, 2016. According to the study results, the conception rate was 31.67% and the mice in the large cages had a higher rate of conception than those in the small cages (56.7 vs. 6.7%). The gestation period was $22{\pm}1.6days$ (ranges from 21 to27 days), and litter size ranged from 2 to 7, with a mean of $4.26{\pm}1.37$ in the species. The minimum age for weaning was between $19.2{\pm}1.4days$ (range of 18-21 days). There were no significant differences by sex between mean body weight and external body measurements at birth. However, a significant sexual difference was found from the period of weaning (21 days old) in head and body length, as well as tail length (HBL-weaning, $106.50{\pm}6.02$ vs. $113.34{\pm}4.72mm$, p<0.05; HBL-4 months, $163.93{\pm}5.42$ vs. $182.83{\pm}4.32mm$, p<0.05; TL-4 months, $107.23{\pm}3.25$ vs. $93.95{\pm}2.15mm$, p<0.05). Gompertz and Logistic growth curves were fitted to data for body weight and lengths of head and body, tail, ear, and hind foot. In two types of growth curves, males exhibited greater asymptotic values ($164.840{\pm}7.453$ vs. $182.830{\pm}4.319mm$, p<0.0001; $163.936{\pm}5.415$ vs. $182.840{\pm}4.333mm$, p<0.0001), faster maximum growth rates ($1.351{\pm}0.065$ vs. $1.435{\pm}0.085$, p<0.05; $2.870{\pm}0.253$ vs. $3.211{\pm}0.635$, p<0.05), and a later age of maximum growth than females in head and body length ($5.121{\pm}0.318$ vs. $5.520{\pm}0.333$, p<0.05; $6.884{\pm}0.336$ vs. $7.503{\pm}0.453$, p<0.05). However, females exhibited greater asymptotic values ($105.695{\pm}5.938$ vs. $94.150{\pm}2.507mm$, p<0.001; $111.609{\pm}14.881$ vs. $93.960{\pm}2.150mm$, p<0.05) and longer length of inflection ($60.306{\pm}1.992$ vs. $67.859{\pm}1.330mm$, p<0.0001; $55.714{\pm}7.458$ vs. $46.975{\pm}1.074mm$, p<0.05) than males in tail length. These growth rate constants, viz. the morphological characters and weights of the males and females, were similar to each other in two types of growth curves. These results will be used as necessary data to study species specificity of T. triton with biological foundations.

A Study on the Archives and Records Management in Korea - Overview and Future Direction - (한국의 기록관리 현황 및 발전방향에 관한 연구)

  • Han, Sang-Wan;Kim, Sung-Soo
    • Journal of Korean Society of Archives and Records Management
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    • v.2 no.2
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    • pp.1-38
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    • 2002
  • This study examines the status quo of Korean archives and records management from the Governmental as well as professional activities for the development of the field in relation to the new legislation on records management. Among many concerns, this study primarily explores the following four perspectives: 1) the Government Archives and Records Services; 2) the Korean Association of Archives; 3) the Korean Society of Archives and Records Management; 4) the Journal of Korean Society of Archives and Records Management. One of the primary tasks of the is to build the special depository within which the Presidential Library should be located. As a result, the position of the GARS can be elevated and directed by an official at the level of vice-minister right under a president as a governmental representative of managing the public records. In this manner, GARS can sustain its independency and take custody of public records across government agencies. made efforts in regard to the preservation of paper records, the preservation of digital resources in new media formats, facilities and equipments, education of archivists and continuing, training of practitioners, and policy-making of records preservation. For further development, academia and corporate should cooperate continuously to face with the current problems. has held three international conferences to date. The topics of conferences include respectively: 1) records management and archival education of Korea, Japan, and China; 2) knowledge management and metadata for the fulfillment of archives and information science; and 3) electronic records management and preservation with the understanding of ongoing archival research in the States, Europe, and Asia. The Society continues to play a leading role in both of theory and practice for the development of archival science in Korea. It should also suggest an educational model of archival curricula that fits into the Korean context. The Journals of Records Management & Archives Society of Korea have been published on the six major topics to date. Findings suggest that "Special Archives" on regional or topical collections are desirable because it can house subject holdings on specialty or particular figures in that region. In addition, archival education at the undergraduate level is more desirable for Korean situations where practitioners are strongly needed and professionals with master degrees go to manager positions. Departments of Library and Information Science in universities, therefore, are needed to open archival science major or track at the undergraduate level in order to meet current market demands. The qualification of professional archivists should be moderate as well.