• Journal of Chest Surgery
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• v.49 no.6
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• pp.427-434
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• 2016

Background: Recent studies have demonstrated the benefits of off-pump coronary bypass grafting over the on-pump technique in patients with chronic kidney disease (CKD). To further reduce the risk of acute kidney injury and the need for renal replacement therapy, even in patients undergoing off-pump coronary artery bypass grafting, we adopted protocol-based perioperative management for patients with CKD. Methods: From December 2012 to March 2015, 265 patients underwent isolated off-pump coronary artery bypass grafting. To analyze renal function in a stable condition, we excluded 12 dialysis-dependent end stage renal failure and 10 emergency or urgent cases. Among the remaining 243 patients, 208 patients had normal kidney function (normal group), and 35 patients had CKD (CKD group). Minimizing contrast exposure, ensuring adequate hydration, using strict drug dosage adjustment, and optimizing hemodynamic status were key elements of the protocol for the CKD group. Results: The risk of acute kidney injury was about ${\times}3$ higher in the CKD group than in the normal group (p=0.01). Estimated glomerular filtration rates and serum creatinine levels deteriorated until the third postoperative day in the CKD group. However, by adopting protocol-based perioperative management, this transient renal dysfunction recovered to preoperative levels by the fifth postoperative day without requiring renal replacement therapy in all cases. Conclusion: Off-pump coronary bypass surgery combined with this protocol-based perioperative management strategy in patients with non-dialysis-dependent CKD could mostly be performed without renal replacement therapy.

• Journal of Chest Surgery
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• v.36 no.8
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• pp.630-632
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• 2003

In off-pump coronary artery bypass grafting (CABG), multiple proximal anastomosis may increase the risk of cerebral embolism (air, debris) and aortic injury (dissection, pseudoaneurysm). Radial artery (RA) has no intraluminal valve such as saphenous vein. We applied Cabrol technique using aortic root replacement for proximal anastomosis in off-pump CABG. Cabrol technique using RA graft can reduce numbers of proximal anastomosis and reduce number of aortic manipulation in off-pump CABG. We report a Cabrol technique for proximal anastomosis in off-pump CABG with RA graft.

• Journal of applied mathematics & informatics
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• v.32 no.1_2
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• pp.129-136
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• 2014

One of the fundamental issues in the design of dynamic spectrum access policy is the modeling of the dynamic behavior of channel occupancy by primary users. Under a Markovian modeling of channel occupancy, a periodic sensing and greedy access policy is known as one of the simple and practical dynamic spectrum access policies in cognitive radio networks. In this paper, the primary occupancy of each channel is modeled as a discrete-time alternating renewal process with generally distributed on- and off-periods. A periodic sensing and greedy access policy is constructed based on the general channel occupancy model. Simulation results show that the proposed policy has better throughput than the policies using channel models with exponentially distributed on- or off-periods.

• Journal of radiological science and technology
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• v.1 no.1
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• pp.37-43
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• 1978

This Study was conducted, during the period of 8-16th, August in 1977 and 27th, January through 2, Feburury in 1978, to measure laking off and on time for patient's clothes at the radiologic department in general hospitals. The study dealt with three general hospitals which were classified into groups by ownerships; two university hospitals, one private hospitals. The scope of the study was limited to measurement's of taking off and on time except taking a radiograph. The results were summarized as follows: [1] In Summer, the average taking off ana on tine for male was 3 minutes and 7 seconds and 3 minutes and 43 seconds for female. The latter was longer than that for the former. [2] In Winter, the mean taking off and on time for male was 3 minutes 42 seconds, 4 minutes 17 seconds for female. [3] In this respect, the average taking off and on time for female was longer than that for male and that for winter was expended that for summer. [4] In Summer, regardless of age group and sex, the average taking off and on time for taking a radiograph was 3 minutes 25 seconds, and 3 minuteds 59 seconds in Winter. [5] Regardless of season, sen, and age, the mean time expended to take off and on for taking a radiograph was 3 minutes 43 seconds.

• Korean Journal of Mathematics
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• v.15 no.1
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• pp.71-78
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• 2007

We consider arrival process and ON/OFF source model which allows for long packet trains and long inter-train distances. We prove the weak convergence of theses processes to Fractional Brownian motion. Finally, we figure out the coefficients of $B_H(t)$ and time $t$ when ON/OFF periods have the Pareto distribution.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.207-215
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• 2000

This study theoretically investigated the roll-off cleanliness operation to eliminate the built-in contaminants which are primarily the result of manufacturing and assembly procedures first. A rigorous analytical examination of the cleaning process associated with hydraulic systems was performed by developing the general filtration process equations. The sloughing process by which built-in contaminant is entrained in the system fluid was examined during the development of a general analytical expression for sloughing rate. This sloughing rate expression in conjunction with the filtration process equations have lead to a relationship rate expression in conjunction with the filtration process equations have lead to a relationship which describes the flushing and clean-up operation for the hydraulic systems. The effects of the primary roll-off cleanliness factors was discussed and illustrated on the figures. Then, the analytical results was shown to be usefully applied into the design of roll-off flushing equipment for the hydraulic system of a tractor.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.16 no.4
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• pp.16-23
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• 2020

In this study, the control characteristics and effects of control methods on heating performance and energy consumption for the hot water floor radiant heating control system of a residential apartment were research by experiment. As a control method, On-Off control and outdoor reset control methods with GRNN(General Regression Neural Network) and without GRNN are considered. Also, the control performances with regard to improvement of indoor thermal environment and reduction of energy consumption are compared, respectively. Experiment results show that the performance of the control method with GRNN is better than that of conventional on-off control method without GRNN in the responses of room set temperature and energy saving.

• Earthquakes and Structures
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• v.8 no.3
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• pp.699-712
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• 2015

Bracing structures with off-centre bracing system is one of the new resistant systems that frequently used in the frame with pin connections. High ductility, high-energy dissipation and decrease of base shear are advantages of this bracing system. However, beside these advantages, reconstruction and hard repair of off-centre bracing system cause inappropriate performance in the earthquake. Therefore, in this paper, the goal is investigating the behavior of this type of bracing system with ductile element (circular dissipater), in order to providing replacement of damaged member without needing repair or reconstruction of the general system. To achieve this purpose, some numerical studies have been performed using ANSYS software, a frame with off-centre bracing system and optimum eccentricity (OBS-C-O) and another frame with the same identifications without ductile element (OBS) has been created. In order to investigate precisely on the optimum placement of circular elements under monotonic load again three steal frames were modeled. Furthermore, the behavior of this general system investigated for the first time, linear and nonlinear behavior of these two steel frames compared to each other, to achieve the benefit of using the circular element in an off-centre bracing system. Eventually, the analytical results revealed that the performance of steel ring at the end of off-centre braces system illustrating as a first defensive line and buckling fuse in the off-centre bracing system.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.334.2-334
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• 2002

In conventional model updating using single-objective optimization techniques, imcompatible physical data are compared with each other using weighting factors. There are no general rules fur selecting the weighting factors since they are not directly related with the dynamic behavior of an updated model. So one of the most difficult tasks, in mr)del updating study, is 'balancing among the correlations', i.e. 'trade-off'. (omitted)

• Korean Journal of Clinical Pharmacy
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• v.24 no.4
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• pp.265-271
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• 2014

Objective: This study aims to explore the perception of off-label use of medications and the provision of informed consents from the general public's perspective. Methods: The study subjects (n=291) were recruited from 7 cities in Korea through a convenience sampling method. The self-administered questionnaire with 13 items was issued and collected. The study subjects who have had a pharmaceutical job were excluded. Results: The total of 231 respondents was included. Only 23% of respondents were familiar with the concept of off-label use of medications. Eighty five percent of respondents (n=196) stated that the prescribers should explain the off-label use of a medication to their patients. The preferred method for delivering the message was the oral explanation (n=122, 53%), followed by oral explanation plus a pamphlet (n=94, 41%). The safety issue is the most concerned aspect regarding the off-label drug use, also effectiveness and insurance coverage. The majority of respondents (n=217, 94%) agreed that the prescriber should get a consent from patients before prescribing medications for off-label use. They preferred written consent to oral consent (140 vs. 77). Conclusion: This study demonstrated general publics are infrequently aware of off-label use of medications. It is important to raise public awareness of the off-label use of medications and to openly discuss its pros and cons for safe and effective drug therapy.