• Korean Journal of Clinical Pharmacy
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• v.30 no.3
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• pp.169-176
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• 2020

Background: Most meta-analyses of risk factors for severe or critical outcomes in patients with COVID-19 only included studies conducted in China and this causes difficulties in generalization. Therefore, this study aimed to systematically evaluate the risk factors in patients with COVID-19 from various countries. Methods: PubMed, Embase, and Web of Science were searched for studies published on the mortality risk in patients with COVID-19 from January 1 to May 7, 2020. Pooled estimates were calculated as odds ratio (OR) with 95% confidence interval (CI) using the random-effects model. Results: We analyzed data from seven studies involving 26,542 patients in total in this systematic review and meta-analysis. Among the patients, 2,337 deaths were recorded (8.8%). Elderly patients and males showed significantly higher mortality rates than young patients and females; the OR values were 3.6 (95% CI 2.5-5.1) and 1.2 (95% CI 1.0-1.3), respectively. Among comorbidities, hypertension (OR 2.3, 95% CI 1.1-4.6), diabetes (OR 2.2, 95% CI 1.2-3.9), cardiovascular disease (OR 3.1, 95% CI 1.5-6.3), chronic obstructive pulmonary disease (OR 4.4, 95% CI 1.7-11.5), and chronic kidney disease (OR 4.2, 95% CI 2.0-8.6) were significantly associated with increased mortalities. Conclusion: This meta-analysis, involving a huge global sample, employed a systematic method for synthesizing quantitative results of studies on the risk factors for mortality in patients with COVID-19. It is helpful for clinicians to identify patients with poor prognosis and improve the allocation of health resources to patients who need them most.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.5
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• pp.101-106
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• 2011

In this paper, our goal is to design the controller which operates a manufacturing system, discrete event system, guaranteeing user specification. In specially, based on supervisory control theory W. M. Wonham, our work consists in performing the controller using Petri nets possible parallelism. In addition, we consider the problem of allocation for resources sharing of the issues to consider when designing using Petri net. The controller can be generated by synthesis of user specification model and plant model after giving the management for the resource sharing. This created controller can control the deadlock and starvation which can occur in the case with resource sharing. Previous studies proposed the Constrained Synchronous Reachability graph to synthesis of the two Petri nets models. Therefore, we provide the controlled system which forbids a deadlock and starvation using the result of previous studies.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.1
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• pp.39-45
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• 2008

High-Rate Wireless Personal Area Networks (HR-WPANs) in IEEE 802.15.3 standard use a TIme Devision Multiple Access (TDMA) protocol to support isochronous traffic. Isochronous traffic requires a delay-bounded service. However, the HR-WPAN standard suffers from long access delay and association delay. In this paper, we propose an enhanced MAC protocol for the delay-bounded traffic. This proposed protocol provides a way that a central node is able to collect traffic status on all member nodes. Furthermore, by utilizing the information, a scheduling algorithm is also proposed in order to synchronize the instant of a packet transmission with that of the packet arrival. With the proposed protocol and algorithm, the delay of access and association can be reduced. Performance analysis is carried out and the significant performance enhancement is observed.

• Journal of IKEEE
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• v.22 no.3
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• pp.658-663
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• 2018

In this paper, we consider node deployment algorithms for the sequence-based localization (SBL) which is recently employed for in-door positioning systems, Whereas previous node selection or deployment algorithms seek to place nodes at centrold of the region where more targets are likely to be found, we observe that the boundaries dividing such regions can be good locations for the nodes in SBL systems. Motivated by this observation, we propose an efficient node deployment algorithm that determines the boundaries by using the well-known K-means algorithm and find the potential node locations based on the bi-section method for low-complexity design. We demonstrate through experiments that the proposed algorithm achieves significant localization performance over random node allocation with a substantially reduced complexity as compared with a full search.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.4
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• pp.394-400
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• 2018

A heterogenous network is the one of key technologies for 5G, where one cell is divided into small cells in order to extend coverage and support high data rates. Divided cells aggravates the intercell interference problem as the cell edge increases. In order to avoid the intercell interference, it is the best to allocate the different spectrum for each cells. However, it also decreases the spectral efficiency. Therefore, the trade-off between the spectral efficiency gain and the signal quality loss by the interference should be considered for an efficient spectrum sharing in the heterogenous network. The adaptive modulation is the method to change the transmitted bit according to the channel quality, which is adopted as the standard in the most practical communication systems. It should be considered to applied the performance analysis into the practical systems. In this paper, the overall cell data rates is analyzed for the heterogenous network under the adaptive modulation. The Monte Carlo simulation results verify the correctness of the analysis.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2131-2136
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• 2016

Background: Cancer is currently one of the main public health problems all over the world and its economic burden is substantial both for health systems and for society as a whole. To inform priorities for cancer control, we here estimated years of potential life lost (YPLL) and productivity losses due to cancer-related premature mortality in Iran from 2006 to 2010. Materials and Methods: The number of cancer deaths by sex and age groups for top ten leading cancers in Iran were obtained from the Ministry of Health and Medical Education. To estimate the YPLL and the cost of productivity loss due to cancer-related premature mortality, the life expectancy method and the human capital approach were used, respectively. Results: There were 138,228 cancer-related deaths in Iran (without Tehran province) of which 76 % (106,954) were attributable to the top 10 ranked cancers. Some 63 % of total cancer-related deaths were of males. The top 10 ranked cancers resulted in 106,766,942 YPLL in total, 64,171,529 (60 %) in males and 42,595,412 (40%) in females. The estimated YPPLL due to top 10 ranked cancers was 58,581,737 during the period studied of which 32,214,524 (54%) was accounted for in males. The total cost of lost productivity caused by premature deaths because of top 10 cancers was 1.68 billion dollars (US$) from 2006 to 2010, ranging from 251 million dollars in 2006 to 283 million dollars in 2010. Conclusions: This study showed that the economic burden of premature mortality attributable to cancer is significant for Iranian society. The findings provide useful information about the economic impact of cancer for health system policy/decision makers and should facilitate planning of preventive intervention and effective resource allocation.

• The Journal of the Korea Contents Association
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• v.6 no.2
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• pp.117-126
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• 2006

Although the Java bytecode has numerous advantages, there are also shortcomings such as slow execution speed and difficulty in analysis. In order to overcome such disadvantages, bytecode analysis and optimization must be performed. First control flow of the bytecode should be analyzed, after which information is required regarding where the variables are defined and used to conduct data flow analysis and optimization. There may be cases where variables with an identical name contain different values at a different location during the execution according to the value assigned to a variable in each location. Therefore, in order to statically determine the value and type, the variables must be separated according to allocation. In order to do so, the variables can be expressed using a static single assignment form. After the transformation into a static single assignment form, the type information of each node expressed by each variable and expression must be configured to perform static analysis and optimization. Based on the basic type information, this paper proposes a method for finding related equivalent nodes, setting the nodes with strongly connection components and efficiently assigning each node the type.

• Journal of Advanced Navigation Technology
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• v.14 no.5
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• pp.767-774
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• 2010

Due to advantages of NAND flash memory such as non-volatility, low access latency, low energy consumption, light weight, small size and shock resistance, it has become a better alternative over traditional magnetic disk drives, and has been widely used. Traditional DBMSs including mobile DBMSs may run on flash memory without any modification by using Flash Translation Layer (FTL), which emulates a random access block device to hide the characteristics of flash memory such as "erase-before-update". However, most existing FTLs are optimized for file systems, not for DBMSs, and traditional DBMSs are not aware of them. Also, traditional DBMSs do not consider the characteristics of flash memory. In this paper, we propose a flash-conscious storage system for DBMSs that utilizes flash memory as a main storage medium, and carefully put the characteristics of flash memory into considerations. The proposed flash-conscious storage system exploits log records to avoid costly update operations. It is shown that the proposed storage system outperforms the state.

• The Korean Nurse
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• v.31 no.5
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• pp.53-64
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• 1992

A nurse is give much weight in the professions of hospital.The effective achievement of a goal of hospital organization needs to get nurses to contribute the structure positively through the rational personnel management of the nurses.The operation of performance rating system is necessary to improve because the nurses hold negative opinions about the resonable management of that system in most Korean hospitals.Therefore, the prupose of this research was to suggest an efficient method to solve the problem in connection with the management of nurses performance rating system.The results of the study are summarized as follows.1. As the performance rating implies the evaluation of employee's functional accomplishment and ability, and essential condition of the job was surveyed according to the job analysis of nursing activities and nurse position.That is to say, Nusrses' performances and capability is estimated in comparision with the condition of the job. 2. It is required adequacy for evaluation factors in performance rating.That is, $\circled1$ as for those who work in psychiatry or newborn baby room they should be appraied in terms of different factors from those applicable to whom work in a general staffs. $\circled2$ Evaluation factors should be concrete so that the quality and quantity of work and the potential ability of them can be correctly appraised. 3. In order to realize the object of perfamance rating system, the training on chief nurses are quite important. Also, careful practices and continuous supplementary training are required before the system is introduced.First of all, the appropriate evaluation can be mad by continuing to record the rating objects every day for the purpose of obtaining the objectivity of rating. 4. In course of transfering of the position and training, the induction of self-rating system and presentation of self-description is required to supplement functionally the performance rating system. 5. For the efficiency of nurses' performance rating system, the results of performance rating system must be reflected in promotion, allocation and training course, which makes the nurses have the motives and the organization accomplish the goal of modern nursing through its activation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.328-331
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• 2007

In this paper, the capacity of the clustered response model for correlated MIMO-OFDM fading channel is investigated. We compare the capacities achieved by correlation at receiver and achieved by correlation at both the transmitter and the receiver for the case where the channel is known and unknown at the transmitter are considered. It is found that the capacity achieved by correlation at receiver is better than the other. It is also shown that the capacity using the water-filling methed is larger than that using the uniform power allocation due to the water-filling gain. But it is negligible when the number of clusters is over the maximum rank of the sum correlation matrix and SNR is high.