• Journal of information and communication convergence engineering
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• v.2 no.1
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• pp.5-8
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• 2004

DS-COMA is now a matured multiple access technology that utilizes spreading codes for user separation. In this paper, we attempt to improve the performance of a multiuser DS-COMA system with a unique chip shaping code called Carrier Interferometry (CI) code. The CI codes exhibit an excellent correlation property that can be used in many applications. In DS-COMA with CI codes (CI/DS-COMA), the symbols are spread by a spreading code and then the chip signals are shaped using a CI code. Due to the correlation property of the CI code, a diversity gain from the shaped chip signals is achieved and the performance of DS-COMA is significantly improved. Comparison study demonstrates that the DS-COMA with CI outperforms the conventional DS-COMA system in multiuser environments.

• Korean Journal of Adult Nursing
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• v.19 no.1
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• pp.45-54
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• 2007

Purpose: This study was to identify the significant acute physiological predictors of mortality and of functional and cognitive recovery in hemorrhagic stroke patients. Methods: The subjects were 108 hemorrhagic stroke patients admitted to Neurological Intensive Care Unit of a university hospital. Results: The significant physiological predictors of mortality and of functional and cognitive recovery were quite different upon admission Glasgow Coma Scale scores: respiratory rate, hematocrit, serum pH, osmolality, and $PaCO_2$ were the predictors in the subjects with a high Glasgow Coma Scale scores while blood pressure, $PaO_2$, respiratory rate, and hematocrit in the subjects with a low Glasgow coma scale scores. Conclusion: The physiological derangements induced by acute stroke are undoubtedly influence clinical outcome. More study is required to determine their diverse impacts on clinical outcomes.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.34.1-34.1
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• 2015

Deep archival V and I image data taken with Hubble Space Telescope have been used to investigate compact stellar objects in an anemic spiral galaxy NGC 4921 in the Coma cluster. We resolve a significant fraction of globular clusters based on the reconstructed master drizzled image data. The color distribution of globular clusters (GCs) shows a clear bimodal distribution. The blue and red GC populations show significantly different radial number density profiles. We derive the turnover magnitudes of globular cluster luminosity functions (GCLFs) for the blue and red GCs in the bulge and halo of NGC 4921. We also derive the GCLFs of two Coma cD galaxies, NGC 4874 and NGC 4889, and one coma S0 galaxy, NGC 4923. Turnover magnitudes of GCs in four galaxies agree well within uncertainties. A mean distance of four Coma galaxies is derived from turnover magnitudes of GCLFs. A value of the Hubble constant is determined from this distance estimate and radial velocity of the Coma. We discuss implications of our results in relation with the recent determinations of the Hubble constant.

• Journal of Korean Medicine Rehabilitation
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• v.18 no.3
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• pp.157-171
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• 2008

Objectives : To report one case of semi-coma patient was treated by scalp acupuncture with electric stimulation. Methods : Patient (state of semi-coma) was treated by scalp acupuncture with electric stimulation, herbal medication and physical therapy. The improvement of patient was measured every other week by Glasgow Coma Scale(GCS), Modified Bathel Index(MBI), National Institutes of Health Stroke Scale(NIHSS). Results : We observed the patient decrease in NIHSS score and increase in GCS and MBI. Symptoms of patient such as semi-coma were improved following the treatment. Conclusions : It is suggested that oriental medical treatment; scalp acupuncture with electric stimulation, herbal medication and physical therapy were effective in semi-coma caused by traumatic brain injury.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.54.3-54.3
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• 2021

The Coma cluster serves as an ideal laboratory to study the cluster assembly history. It is known as a typical example of relaxed galaxy clusters. However, recent X-ray, radio and optical observations revealed a number of substructures in Coma. The NGC 4839 group is an interesting substucture in the sense that it is overlappled with the X-ray bright component in the south-west region. Recent hydrodynamical simulations in the literature suggest that the NGC 4839 group came from the north-east direction of Coma, passed the apocenter about 1 Gyr ago, and started a second infall to the Coma core recently. Interestingly a number of E+A galaxies are located along the filament connecting the NGC 4839 group and the Coma core. We are surveying a wide area covering the NGC 4839 group to search for globular clusters and use them to investigate any connection between the globular clusters and the merger scenario of the NGC 4839 group. We utilized Subaru Hyper Suprime-Cam archival images of two circular fields with diameter ~1.8 deg, covering the Coma core and the NGC 4839 group. We discuss the results with regard to the formation history of the NGC 4839 group.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.28-30
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• 2003

COMA셀룰라 시스템의 용량은 간섭의 양에 따라 결정되므로 이 간섭량을 정확히 계산해야 시스템 성능 평가를 정확히 할 수 있다. 본 논문은 COMA셀룰라 시스템의 역방향 타셀 간섭량을 계산하기 위해 Riemann-Zeta 함수를 이용하여 임의의 전파 감쇄 지수에도 적용할 수 있는 근사식을 제시하고 시abf레이션 결과와 비교하여 그 효용을 살펴 보았다. 제안된 근사식을 이용해 계산한 시스템 용량 상한식은 시뮬레이션을 통해 얻은 용량과 근사한 결과를 얻을 수 있었다. 제안된 타셀 간섭 근사식은 복합적인 전파 환경이 고려되어야 할 계층셀 시스템에서의 간섭 일 용량 계산과 알고리즘 검증에 유용하게 사용될 수 있을 것으로 생각된다.

• Journal of Preventive Medicine and Public Health
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• v.51 no.6
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• pp.265-274
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• 2018

Objectives: A positive association between air pollution and both the incidence and prevalence of diabetes mellitus (DM) has been reported in some epidemiologic and animal studies, but little research has evaluated the relationship between air pollution and diabetic coma. Diabetic coma is an acute complication of DM caused by diabetic ketoacidosis or hyperosmolar hyperglycemic state, which is characterized by extreme hyperglycemia accompanied by coma. We conducted a time-series study with a generalized additive model using a distributed-lag non-linear model to assess the association between ambient air pollution (particulate matter less than $10{\mu}m$ in aerodynamic diameter, nitrogen dioxide [$NO_2$], sulfur dioxide, carbon monoxide, and ozone) and emergency department (ED) visits for DM with coma in Seoul, Korea from 2005 to 2009. Methods: The ED data and medical records from the 3 years previous to each diabetic coma event were obtained from the Health Insurance Review and Assessment Service to examine the relationship with air pollutants. Results: Overall, the adjusted relative risks (RRs) for an interquartile range (IQR) increment of $NO_2$ was statistically significant at lag 1 (RR, 1.125; 95% confidence interval [CI], 1.039 to 1.219) in a single-lag model and both lag 0-1 (RR, 1.120; 95% CI, 1.028 to 1.219) and lag 0-3 (RR, 1.092; 95% CI, 1.005 to 1.186) in a cumulative-lag model. In a subgroup analysis, significant positive RRs were found for females for per-IQR increments of $NO_2$ at cumulative lag 0-3 (RR, 1.149; 95% CI, 1.022 to 1.291). Conclusions: The results of our study suggest that ambient air pollution, specifically $NO_2$, is associated with ED visits for diabetic coma.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.4
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• pp.143-152
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• 2021

It is very important to learn behavioral policies that allow multiple agents to work together organically for common goals in various real-world applications. In this multi-agent reinforcement learning (MARL) environment, most existing studies have adopted centralized training with decentralized execution (CTDE) methods as in effect standard frameworks. However, this multi-agent reinforcement learning method is difficult to effectively cope with in a dynamic environment in which new environmental changes that are not experienced during training time may constantly occur in real life situations. In order to effectively cope with this dynamic environment, this paper proposes a novel multi-agent reinforcement learning system, C-COMA. C-COMA is a continual learning model that assumes actual situations from the beginning and continuously learns the cooperative behavior policies of agents without dividing the training time and execution time of the agents separately. In this paper, we demonstrate the effectiveness and excellence of the proposed model C-COMA by implementing a dynamic mini-game based on Starcraft II, a representative real-time strategy game, and conducting various experiments using this environment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1267-1268
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• 2013

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.565-568
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• 2005

Hyperosmolar nonketotic coma complicated in diabetes mellitus has been a rare cause of rhabdomyolysis, although increasingly reported recently. Acute renal failure can be complicated in 15 percent of rhabdomyolysis patients, but is rare in the case of rhabdomyolysis caused by diabetic hyperosomolar nonketotic coma. We report a 14 years-old boy with acute renal failure complicated by rhabdomyolysis caused by diabetic hyperosmolar coma.