• Wind and Structures
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• 제5권2_3_4호
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• pp.115-126
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• 2002

A mesoscale meteorological model is applied to simulate turbulent airflow and eddy shedding over the Isle of Arran, SW Scotland, UK. Under conditions of NW flow, the mountain ridge of Kintyre, located upwind of Arran, induces gravity waves that also affect the airflow over the island. The possibility to nest domains allows description of the airflow over Arran with a very high resolution grid, while also including the effects of the surrounding mainland of Scotland, in particular of the mountain ridge of Kintyre. Initialised with a stably stratified NW flow, the mesoscale model simulates quasi-stationary gravity waves over the island induced by Kintyre. Embedded in the larger scale wave trains there is continuous development of small-scale transient eddies, created at the Arran hill tops, that move downstream through the stationary wave field. Although the transient eddies are more frequently simulated on the northern island where the terrain is more pronounced, they are also produced over Tighvein, a hill of 458 m on the southern island where measurements of surface pressure and 2 m meteorological variables have been recorded at intermittent intervals between 1996 and 2000. Comparison between early observations and simulations so far show qualitatively good agreement. Overall the computations demonstrate that turbulent flow can be modelled with a horizontal resolution of 70 m, and describe turbulent eddy structure on wavelength of only a few hundred metres.

• 한국초전도ㆍ저온공학회논문지
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• 제22권2호
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• pp.12-16
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• 2020

Circulating cooling systems consume a lot of water, and most of the water from river, which contains a large amount of Ca2+, Mg2+, et al, and has the characteristics of high hardness and large turbidity. The water can form scale on the surface of the heat exchanger and the pipes, which would reduce the heat transfer efficiency and affect the heat exchanger's length of service. In this study, the Superconducting High Gradient Magnetic Separation (S-HGMS) technology was used in river water treatment and the effects of agent A, agent B, and S-HGMS on the removal of hardness and turbidity were discussed. The results showed that the hardness removal rate reached 71.3% and the turbidity was decreased to 0.5 NTU.

• 천문학회보
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• 제42권2호
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• pp.42.2-42.2
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• 2017

The Large Magellanic Cloud (LMC) is a unique target to study the detail structures of molecular clouds and star-forming regions, due to its proximity and face-on orientation from us. Most part of the astrophysical subjects for the LMC have been investigated, but the magnetic field is still veiling despite its role in the evolution of the interstellar medium (ISM) and in the main force to influence the star formation process. Measuring polarization of the background stars behind interstellar medium allows us to describe the existence of magnetic fields through the polarization vector map. In this presentation, I introduce the near-infrared polarimetric results for the $39^{\prime}{\times}69^{\prime}$ field of the northeastern region of the LMC and the N159/N160 star-forming complex therein. The polarimetric observations were conducted at IRSF/SIRPOL 1.4 m telescope. These results allow us to examine both the global geometry of the large-scale magnetic field in the northeastern region and the close structure of the magnetic field in the complex. Prominent patterns of polarization vectors mainly follow dust emission features in the mid-infrared bands, which imply that the large-scale magnetic fields are highly involved in the structure of the dust cloud in the LMC. In addition, local magnetic field structures in the N159/N160 star-forming complex are investigated with the comparison between polarization vectors and molecular cloud emissions, suggesting that the magnetic fields are resulted from the sequential formation history of this complex. I propose that ionizing radiation from massive stellar clusters and the expanding bubble of the ionized gas and dust in this complex probably affect the nascent magnetic field structure.

• Asia pacific journal of information systems
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• 제12권3호
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• pp.1-20
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• 2002

For the last decade, some leading groups of corporations in Korea have integrated and managed their Information Systems(IS) functions. Each group established a separate System Management(SM) company to manage the IS and tried to get a synergy effect from the integration. These attempts, however, were not initiated by any one company. Rather they were group efforts. Moreover, the previous measuring tools evaluated IS with the scope of technical performance or quantitative user satisfaction using an absolute scale. Obscure criteria were used in an attempt to present improvements in IS function which were qualitatively weak. This study evaluates whether integration has been efficient and successful. For this purpose, we evaluate the performance efficiency of IS functions with Data Envelopment Analysis(DEA) methodology. In comparison with prior methods, DEA presents the rate of relative efficiency, the efficiency frontier for improving inefficiency, the degree of improvement(slack), and the guideline to construct any benchmark(reference set). For our DEA evaluation, this study selected a leading group of 23 companies in Korea. Our experimental results are as follows. First, efficiency was rated low on average. It also demonstrates that the motivation of performance efficiency of IS functions is deficient. Second, the result of the test to find the existence of economy of scale and scope shows that the growth of an organization and industrial characteristics do not affect IS performance efficiency from the perspective of user satisfaction. Finally, the comparison with other evaluation approaches informs us that DEA can be a complementary evaluation method which supports other measuring tools.

• The Journal of Korean Physical Therapy
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• 제20권4호
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• pp.1-6
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• 2008

Purpose: We studied the correlation between BBS (Berg Balance Scale), Functional Reach Test (FRT), Timed-Up & Go test (TUG), Stability Index (STI), MBI (Modified Barthel Index), and Fall History. Methods: We recruited 20 stroke patients from the Gang Dong Gu Health Care Center in Seoul, Korea. All subjects could walk with or without an assisting device. Subjects first completed a questionnaire pertaining to their fall history and Activity of Daily Living (MBI), and then were evaluated with BBS, TUG, FRT, and STI. We used the Tetrax posturography system that calculates a STI based on fluctuations in vertical ground reaction forces. The data were analyzed using a Pearson Correlation Coefficient. Results: The BBS and FRT (p<0.05) and MBI (p<0.01) showed a significant positive correlation. BBS negatively correlated with STI and TUG (p<0.01). Fall history and BBS, TUG, MBI, FR, STI did not correlate. Conclusion: The BBS helps predict weight shifting, walking, and ADL, but is not good for predicting fall risk. So, we need to study about factors that affect falling.

• 한국환경과학회지
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• 제25권9호
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• pp.1311-1322
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• 2016

Since the scale and disaster characteristics of volcanic eruptions are determined by their geological features, it is important not only to grasp the current states of the volcanoes in neighboring countries around the Korean Peninsula, but also to analyze the tectonic settings, tectonic regions, geological features, volcanic types, and past eruptional histories of these volcanoes. We created a database of 285 volcanoes around the Korean Peninsula, and then identified a high-risk groups of 29 volcanoes that are highly likely to affect the region, based on conditions such as volcanic activity, the type of rocks at risk of eruption, the distance from Seoul, and high VEI (volcanic explosivity index). In addition, we identified the 10 volcanoes that should be given the highest priority. We selected them through an analysis of data available in literature, such as volcanic ash dispersion results from previous Japanese eruptions, the definition of a large-scale volcano used by Japan's Cabinet Office, and examination of cumulative magma layer volumes from Japan's quaternary volcanoes.

• 대한불안의학회지
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• 제10권2호
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• pp.151-156
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• 2014

Objective : The aim of this study is to analyze the relationship among job stress, depression, and suicidal ideation in firefighters, particularly the mediating effects of depression. Methods : The subjects were 2,136 firefighters in Gangwon-do, who completed the short form of Korean occupational stress scale (KOSS-SF), Korean version of the Beck depression inventory (K-BDI), and the revised scale for suicide ideation (SSI) online in mental health promotion service of firefighters. The data was analyzed with correlation analysis among the variables, and the multiple regression analysis method of Bar-on and Kenny (1986) was used. Results : Job stress showed positive correlations with depression (r=0.493, p <0.01) and suicidal ideation (r=0.296, p<0.01). Depression showed a positive correlation with suicidal ideation (r=0.561, p<0.01). The result of analyzing the mediating effect of depression showed that depression was a full mediator variable between job stress and suicidal ideation. Conclusion : Based on the results, it is very likely that job stress may affect suicidal ideation via depression. These results suggested that the preventive interventions emphasized on depression may be helpful for reduction of suicide in firefighters.

• Asian Pacific Journal of Cancer Prevention
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• 제16권1호
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• pp.217-220
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• 2015

Background: Breast cancer is the second most common cancer in the world and by far the most frequent cancer among women. Objective: This study was conducted to observe the effect of progressive relaxation exercises on anxiety and comfort level of breast cancer patients receiving chemotherapy. Materials and Methods: A control group pre-test/post-test quasi-experimental model was applied with experimental (30) and control (30) groups, who agreed to participate in this study. Data collection was with the "Personnel Information Form, State-Trait Anxiety Inventory and General Comfort Scale". Results: The average age of the patients that participated in the study was $49.1{\pm}7.96$ years. Eighty-three point three percent (n=25) of the patients in the experiment group and 86.7 (n=26) percent of patients in control group were married. Patient state of anxiety post-test mean scores were $36.2{\pm}8.21$ in the experimental group and $43.4{\pm}7.96$ in the control group, the difference being statistically significant (p<0.05). The general comfort scale post-test mean scores were $149.5{\pm}13.9$ in the experimental group and $137.7{\pm}15.0$ in the control group, again statistically significant (p<0.05). Conclusions: Progressive relaxation exercises positively affect patient comfort and anxiety levels in Turkey.

• 한국정밀공학회지
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• 제18권10호
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• pp.69-75
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• 2001

Systems engineering has been utilized in system development primarily for large-scale projects or commercial large-scale systems during the last several decades. We can understand why it would be useful to apply systems engineering to the development of a relatively small system. However, it is difficult to effectively carry out a project due to the complexity in applying the methods of systems engineering. To apply systems engineering to the development of a small system, the system engineering processes should be tailored. We established a requirements driven system design process(RDSDP) that can effectively carry out the system design far a small system. RDSDP is a system design process that treats all the requirements thoroughly and effectively. This is applied by the designer according to a standardized and systematized process during the first phase in design, in which system specifications are made. By using RDSDP, we can affect a reduction of the number of redesign phases in the process of the system design, shorten the period for to make specification, which will then cause the system to succeed in the actual application.

• Clinics in Shoulder and Elbow
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• 제19권3호
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• pp.119-124
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• 2016

Background: The purpose of this study is to evaluate the functional outcomes of reverse total shoulder arthroplasty (RTSA) and to assess factors affecting the patients' subjective satisfaction after RTSA. Methods: Forty-three patients (mean age, $75.0{\pm}5.2years$) who underwent RTSA for cuff tear arthropathy or irreparable cuff tears with preoperative magnetic resonance imaging and pre- and postoperative radiographs at 1 year, and whose various functional outcomes including pain visual analogue scale (VAS), simple shoulder test, Constant score, American Shoulder and Elbow Surgeons score, and active range of motion were evaluated preoperatively and at the last follow-up (>12 months) were enrolled. The outcome parameter was set as a satisfaction scale. Various clinical and radiographic factors were analyzed, and their correlations with postoperative satisfaction were evaluated. Results: All functional scores, VAS pain score, and active forward flexion showed significant improvement after surgery (all p<0.001). Twenty-nine patients were satisfied with the results and 14 were dissatisfied. The presence of pseudoparalysis (p=0.028) and worse preoperative function (all p<0.05) were related with higher satisfaction. Any radiologic parameters did not affect patients' postoperative satisfaction. Conclusions: All patients showed a good functional outcome after RTSA, however the patients' subjective postoperative satisfaction was affected by preoperative functional status (higher satisfaction in poor preoperative function), not by radiological findings.