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A Numerical Study on the Effects of Urban Forest and Street Tree on Air Flow and Temperature (도시숲과 가로수가 대기 흐름과 기온에 미치는 영향에 관한 수치 연구)

  • Kang, Geon;Choi, Wonsik;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
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    • v.38 no.6_1
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    • pp.1395-1406
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    • 2022
  • This study investigated the effects of the urban forest and street trees on flow and temperature distribution in the Daegu National Debt Redemption Movement Memorial Park. For this, we implemented tree-drag and tree-cooling parameterization schemes in a computational fluid dynamics (CFD) model and validated the simulated wind speeds, wind directions, and air temperatures against the measured ones. We used the wind speeds, wind directions, air temperatures predicted by the local data assimilation and prediction system (LDAPS) as the inflow boundary conditions. To investigate the flow and thermal characteristics in the presence of trees in the target area, we conducted numerical experiments in the absence and presence of trees. In the absence of trees, strong winds and monotonous flows were formed inside the park, because there were no obstacles inducing friction. The temperature was inversely proportional to the wind speed. In the presence of trees, the wind speeds(temperatures) were reduced by more than 40 (5)% inside the park with a high planting density due to the tree drag (cooling) effect, and those also affected the wind speeds and temperatures outside the park. Even near the roadside, the wind speeds and temperatures were generally reduced by the trees, but the wind speeds and air temperatures increased partly due to the change in the flow pattern caused by tree drag.

Cinematic Circulation of Meta-verse and Meta-physics (메타버스와 메타피직스의 영화적 순환)

  • Shim, Kwang-hyun
    • Trans-
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    • v.12
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    • pp.81-106
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    • 2022
  • The possibility of metaverse system to be a catalyst for hyper-connected society will be dependent on the speed of connected technological development and its social utilization in the same manner as AI technology. Putting these technical realization processes in brackets, this paper focus on some philosophical-political issues in connection with cognitive-ecological changes in the future cinema which will be influenced by the complexive techno-socio couples of accelerated development of metaverse system. Generally speaking, essence of metaverse system seems to be the degree of immersion by technical accuracy, but is not true. In perspective of cognitive-ecology, flow degree of a picture or photograph is relied not on 'accuracy of representation' but on its message's contextual link-up. In this aspect, real potentiality of metaverse system shall be understood in the context of cognitive-ecological changes of human brain's multi-intelligence networking abilities(intersection of augmentation-simulation and outside-inside) which will be activated in the new structure of natural-social-technological coupling of metaverse system. These cognitive-ecological potentialities have been partially actualized in the cinematic process of tripod mimesis for the longest time, [real contradiction/conflicts (Mimesis-1) -->fictional solutions of cinema (Mimesis-2) --> selective interpretation of spectator's wish fulfillment (Mimesis-3) --> real change (Mimesis-1')]. Therefore metaverse's real potentiality must be considered to be dependent on the possibility of deepening and extending of cinematic circulation between real seperation/problems and ideal connection/solutions. In this context, advanced metaverse system can be compared as a modern technical version of ideal circulation of physics and metaphysics

A Study on Updated Object Detection and Extraction of Underground Information (지하정보 변화객체 탐지 및 추출 연구)

  • Kim, Kwangsoo;Lee, Heyung-Sub;Kim, Juwan
    • Journal of Software Assessment and Valuation
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    • v.16 no.2
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    • pp.99-107
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    • 2020
  • An underground integrated map is being built for underground safety management and is being updated periodically. The map update proceeds with the procedure of deleting all previously stored objects and saving newly entered objects. However, even unchanged objects are repeatedly stored, deleted, and stored. That causes the delay of the update time. In this study, in order to shorten the update time of the integrated map, an updated object and an unupdated object are separated, and only updated objects are reflected in the underground integrated map, and a system implementing this technology is described. For the updated object, an object comparison method using the center point of the object is used, and a quad tree is used to improve the search speed. The types of updated objects are classified into addition and deletion using the shape of the object, and change using its attributes. The proposed system consists of update object detection, extraction, conversion, storage, and history management modules. This system has the advantage of being able to update the integrated map about four times faster than the existing method based on the data used in the experiment, and has the advantage that it can be applied to both ground and underground facilities.

The Meanings and Values of Korean Wave(Hallyu) for the Reunification of the South Korea and North Korea (통일과정에서의 한류의 의미와 가치)

  • Cho, Yong-Ki
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.7
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    • pp.121-139
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    • 2020
  • A variety of the approaches to the unification of the South Korea and North Korea have been implemented based on both the view of the national-centered unification and that of the reunification of the South and North Korea as a unit of nation through political, economic, military and diplomatics. A culture itself plays a significant role for people to understand one another through communicating and sharing cultural values. At this point, Korean-Wave called'Hallyu' should have various meanings and values for the reunification of South and North Korea. It has been expanded to the world beyond Asia as an icon of the culture. In this situation, North Korea is not exceptional. In other words, North Korea should be influenced by the Korean wave. Sharing a cultural value about Korean-Wave between South and North Koreans would be a way to speed up the reunification by having a common sense about the national identifications. The culture of Hallyu reflecting on the national identification could be helpful to enhance national pride and play a part for curing for the scarlet letters that they have got since the Korea was divided by two parts. The North Korean government's distorted policy to have blamed for the South Korean governing would be challenged if the Korean-wave would be epidemic in the Korean peninsular. In addition, if the North Koreans would be perceptive to the real freedom and universal value for the humanity, it would be more feasible for two Koreas to be reunified than before. In fact, it must serve as a catalyst for the reunification, two Koreas experiencing the Korean wave as a cultural value. As a result, the reunification for the people should have a meaning of the universal value as like everyone in the world can pursue for their own happiness. Through the Hallyu, That is, the change of the people's perception to the reunification will facilitate the reunification of two Koreas more than we expected.

Mountain Meteorology Data for Forest Disaster Prevention and Forest Management (산림재해 방지와 산림관리를 위한 산악기상정보)

  • Keunchang, Jang;Sunghyun, Min;Inhye, Kim;Junghwa, Chun;Myoungsoo, Won
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.346-352
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    • 2022
  • Mountain meteorology in South Korea that is covered mountains with complex terrain is important for understanding and managing the forest disaster and forest ecosystems. In particular, recent changes in dryness and/or rainfall intensity due to climate change may cause an increase in the possibility of forest disasters. Therefore, accurate monitoring of mountain meteorology is needed for efficient forest management. Korea Forest Service (KFS) is establishing the Automatic Mountain Meteorology Observation Stations (AMOS) in the mountain regions since 2012. 464 AMOSs are observing various meteorological variables such as air temperature, relative humidity, wind speed and direction, precipitation, soil temperature, and air pressure for every minute, which is conducted the quality control (QC) to retain data reliability. QC process includes the physical limit test, step test, internal consistency test, persistence test, climate range test, and median filter test. All of AMOS observations are open to use, which can be found from the Korean Mountain Meteorology Information System (KoMIS, http://mtweather.nifos.go.kr/) of the National Institute of Forest Science and the Public Data Portal (https://public.go.kr/). AMOS observations with guaranteed quality can be used in various forest fields including the public safety, forest recreation, forest leisure activities, etc., and can contribute to the advancement of forest science and technology. In this paper, a series of processes are introduced to collect and use the AMOS dataset in the mountain region in South Korea.

A study on changes in water cycle characteristics of university campus catchment: focusing on potential evapotranspiration improvement in Mt. Gwanak catchment (대학 캠퍼스 유역의 물순환 특성 변화에 관한 연구: 관악산 유역 잠재증발산량 개선을 중심으로)

  • Kim, Hyeonju;Kim, Young-Oh
    • Journal of Korea Water Resources Association
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    • v.55 no.12
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    • pp.1077-1089
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    • 2022
  • With the construction of Seoul National University (SNU), the Mt. Gwanak watershed has undergone some urbanization. As with other campus catchments, data related to the water cycle is extremely limited. Therefore, this study began by collecting hydrological and meteorological data using Atmos-41, a complex meteorological observation instrument. The observation results of Atmos-41 were validated by analyzing the statistical characteristics and confidence intervals based on the monthly variability of data from the Korea Meteorological Administration. Results of the previous research were used to validate the simulated surface runoff and infiltration using the Storm Water Management Model (SWMM). The potential evapotranspiration (PET) simulated by the SWMM was rectified by comparing it to the Atmos-41 observation data. Multiple regression analysis was employed to adjust for the fluctuations in precipitation, relative humidity, and wind speed because the calculated SWMM PET tends to be underestimated during periods of low temperatures. R2 increased from 0.54 to 0.80 when compared to the Atmos-41 PET. The rate of change in the water cycle as a consequence of the SNU's construction resulted in a 15.7% increase in surface runoff, a 14.2% decrease in infiltration rate, and a 1.6% decrease in evaporation.

Effects of 60 Minutes Cardiopulmonary Resuscitation on Blood Lactic Acid Concentration, Heart Rate, and Rating of Perceived Exertion in Rescuers

  • Han, Seung-Eun;Ahn, Hee-Jeong;Shim, Gyu-Sik;Bang, Sung-Hwan;Song, Hyo-Suk
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.8
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    • pp.195-202
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    • 2022
  • In this study, when cardiopulmonary resuscitation continued for a long time, the rescuer's blood lactic acid concentration, heart rate, and rating of perceived exertion were measured to identify the change in the rescuer's fatigue. Data collection was conducted from July 5 to July 9, 2021, with a total of 24 students, 12 students department of special warfare medical non-commissioned officer, and 12 students department of emergency medical technology at D University, undergoing a two-person alternative chest compression resuscitation for 60 minutes. As a result of the study, the rescuer's blood lactic acid concentration, heart rate, rating of perceived exertion, and chest compression speed were significantly changed according to the duration of CPR (p<.001, p<.001, p<.001, p<.001). blood lactic acid concentrations at every measurement cycle (30 minutes, 40 minutes, 50 minutes, 60 minutes) showed a significant positive correlation with heart rate (r=.696, p<.001, r=.672, p<.001, r=.709, p<.001, r=.782, p<.001), there was also a significant positive correlation with the rating of perceived exertion (r=.476, p<).05, r=.426, p<.05, r=.470, p<.05, r=.470, p<.05). Therefore, monitoring the fatigue of rescuers using heart rate and rating of perceived exertion will be useful for maintaining high-quality chest compression in situations where cardiopulmonary resuscitation is required for a long time.

The effect of oral glucose tolerance testing on changes in arterial stiffness and blood pressure in elderly women with hypertension and relationships between the stage of diabetes and physical fitness levels

  • Lee, Jaesong;Park, Wonil;Sung, Eunsook;Kim, Bokbeom;Kim, Nahyun;Park, Saejong;Shin, Chulho;Park, Jonghoon
    • Korean Journal of Exercise Nutrition
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    • v.24 no.4
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    • pp.34-43
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    • 2020
  • [Purpose] The purpose of this study was to assess changes in blood glucose level, blood pressure, and arterial stiffness after a 75 g oral glucose tolerance test (OGTT) in elderly women aged over 65 years with hypertension and either normal glycemic control, impaired fasting glucose tolerance, or diabetes mellitus. We also wished to investigate the relationship between stages of diabetes and physical fitness. [Methods] A total of 24 elderly women with hypertension were assigned to a control group (CON; n=7), impaired fasting glucose group (IFG; n=9), and diabetes mellitus group (DM; n=8). In each group, blood glucose level, brachial ankle pulse wave velocity (PWV), and blood pressure were measured at baseline as well as 60 and 120 minutes after a 75 g OGTT. Physical fitness factors such as hand grip strength, balance test, 4 m gait speed test, chair stand test, short physical performance battery, and 6-minute walking test were subsequently assessed. [Results] In all three groups, blood glucose levels were significantly increased at 60 and 120 minutes after a 75 g OGTT. In the DM group, blood glucose levels were significantly higher before and after a 75 g OGTT than in the CON group. In the CON group, PWV was significantly increased at 60 minutes after a 75 g OGTT; however, there were no changes in other groups after glucose ingestion. In the CON group, systolic and diastolic blood pressures were significantly decreased at 60 and 120 minutes after a 75 g OGTT compared to baseline. However, there was no change in blood pressure after ingestion in the DM group. The IFG group had greater grip strength than the CON group; however, there were no differences in other variables between the groups. [Conclusion] After a 75 g OGTT, elderly women with hypertension and diabetes maintain higher blood glucose levels compared to those with hypertension alone. Unlike elderly women with hypertension alone, those with hypertension and diabetes did not show changes in arterial stiffness and blood pressure after a 75 g OGTT. Therefore, elderly women with hypertension and diabetes may not be able to control their blood vessels following a 75 g OGTT due to impaired vascular endothelial function. Moreover, there was no association between diabetes stage and physical fitness in elderly women with hypertension.

A Study on the Application of Virtual Space Design Using the Blended Education Method - A La Carte Model Based on the Creation of Infographic - (블렌디드 교육방식을 활용한 가상공간 디자인 적용에 관한 연구 -알 라 카르테 모델 (A La Carte) 인포그래픽 가상공간 제작을 중심으로-)

  • Cho, Hyun Kyung
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.5
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    • pp.279-284
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    • 2022
  • As a study of the blended learning method on design education through the blended learning method, I would like to propose that more advanced learner-led customized design education is possible. Understanding in face-to-face classes and advantages in non-face-to-face classes can be supplemented in an appropriate way in remote classes. Advanced artificial intelligence and big data technology can provide personalized and subdivided learning materials and effective learning methods tailored to learners' levels and interests based on quantified data in design classes. In this paper, it was proposed to maximize the efficiency of the class by applying a method that exceeds the limitations of time and space through the proposal of the A La Carte model (A La Carte). It is a remote class that can be heard anytime, anywhere, and it is also possible to bridge the educational quality and educational gap provided to students living in underprivileged areas. As the goal of fostering creative convergence-type future talents, it is changing with a rapid technological development speed. It is necessary to adapt to the change in learning methods in line with this. An analysis of the infographic virtual space design and construction process through the A La Carte model (A La Carte) proposal was presented. Rather than simply acquiring knowledge, it is expected that knowledge can be sorted, distinguished, learned, and easily reborn with its own knowledge.

Semantic Computing-based Dynamic Job Scheduling Model and Simulation (시멘틱 컴퓨팅 기반의 동적 작업 스케줄링 모델 및 시뮬레이션)

  • Noh, Chang-Hyeon;Jang, Sung-Ho;Kim, Tae-Young;Lee, Jong-Sik
    • Journal of the Korea Society for Simulation
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    • v.18 no.2
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    • pp.29-38
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    • 2009
  • In the computing environment with heterogeneous resources, a job scheduling model is necessary for effective resource utilization and high-speed data processing. And, the job scheduling model has to cope with a dynamic change in the condition of resources. There have been lots of researches on resource estimation methods and heuristic algorithms about how to distribute and allocate jobs to heterogeneous resources. But, existing researches have a weakness for system compatibility and scalability because they do not support the standard language. Also, they are impossible to process jobs effectively and deal with a variety of computing situations in which the condition of resources is dynamically changed in real-time. In order to solve the problems of existing researches, this paper proposes a semantic computing-based dynamic job scheduling model that defines various knowledge-based rules for job scheduling methods adaptable to changes in resource condition and allocate a job to the best suited resource through inference. This paper also constructs a resource ontology to manage information about heterogeneous resources without difficulty as using the OWL, the standard ontology language established by W3C. Experimental results shows that the proposed scheduling model outperforms existing scheduling models, in terms of throughput, job loss, and turn around time.