• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.7
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• pp.14-20
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• 2006

The discharge characteristics for the reset period of sustain pulses of display discharge in address overlapped display driving methode is studied. It has been understood that the display discharge is strongly influenced of not only the wall charge but also the space charge from the experiment result. The first display discharge which comes out exactly after the rest periods strongly depends on the width of the reset period and as for the second display discharge, the dependancy of it is very low. Even if the first display discharge is a little insufficient if the wall charge is accumulated enough, the second display discharge can be stably induced. However, considering the influence of the space charge, it is preferable within the width of $30[{\mu}s}]$ of the reset period. When the rest period is up to $30[{\mu}s}]$, the uniform voltage operation margin of the display discharge of about 12[V] was obtained.

• Journal of Gastric Cancer
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• v.15 no.4
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• pp.278-285
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• 2015

Purpose: Gastric submucosal tumors (SMTs) located very close to the esophagogastric junction (EGJ) are a challenge for gastric surgeons. Therefore, this study reports on the experience of using endoscopic and laparoscopic full-thickness resection (ELFR) with laparoscopic two-layer suturing in such tumors. Materials and Methods: Six patients with gastric SMTs very close to the EGJ underwent ELFR with laparoscopic two-layer suturing at Kyungpook National University Medical Center. With the patient under general anesthesia, the lesser curvature and posterior aspect adjacent to the EGJ were meticulously dissected and visualized using a laparoscopic approach. A partially circumferential full-thickness incision at the distal margin of the tumor was then made using an endoscopic approach under laparoscopic guidance. The SMT was resected using laparoscopic ultrasonic shears, and the gastric wall was closed using two-layer suturing. Thereafter, the patency and any leakage were checked through endoscopy. Results: All the ELFR procedures with laparoscopic two-layer suturing were performed successfully without an open conversion. The mean operation time was $139.2{\pm}30.9$ minutes and the blood loss was too minimal to be measured. The tumors from four patients were leiomyomas, while the tumors from the other two patients were gastrointestinal stromal tumors with clear resection margins. All the patients started oral intake on the third postoperative day. There was no morbidity or mortality. The mean hospital stay was $7.7{\pm}0.8$ days. Conclusions: ELFR with laparoscopic two-layer suturing is a safe treatment option for patients with an SMT close to the EGJ, as major resection of the stomach is avoided.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.12
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• pp.37-44
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• 2011

This paper presents the method of improving the data rate and BER in the inductive coupling link using a BPM signaling method. A complementary switching transmitter is used to remove invalid glitches at transmitted data, and the concept of pre-distortion is introduced to optimize received data. Also, an integrating receiver is used to increase the sampling margin and equalizing transistors are added in the pre-charge path of the integrator and comparator for high frequency operation. The transceiver designed with a 0.13 um CMOS technology operates at 2.4 Gb/s and consumes 5.99 mW from 1.2 V power supply.

• Journal of Radiation Protection and Research
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• v.28 no.2
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• pp.127-135
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• 2003

The primary contributors to the total occupational radiation exposure in operating nuclear power plants are operation and maintenance activities doting refueling outages. The Advanced Power Reactor 1400 (APR1400) includes a number of design improvements and plans to utilize advanced maintenance methods and robotics to minimize the annual collective dose. The major radiation exposure reduction features implemented in APR1400 are a permanent refueling pool seal, quick opening transfer tube blind flange, improved hydrogen peroxide injection at shutdown, improved permanent steam generator work platforms, and more effective temporary shielding. The estimated average annual occupational radiation exposure for APR1400 based on the reference plant experience and an engineering judgment is determined to be in the order of 0.4 man-Sv, which is well within the design goal of 1 man-Sv. The basis of this average annual occupational radiation exposure estimation is an eighteen (18) month fuel cycle with maintenance performed to steam generators and reactor coolant pumps during refueling outage. The outage duration is assumed to be 28 days. The outage work is to be performed on a 24 hour per day basis, seven (7) days a week with overlapping twelve (12) hour work shifts. The occupational radiation exposure for APR1400 is also determined by an alternate method which consists of estimating radiation exposures expected for the major activities during the refueling outage. The major outage activities that cause the majority of the total radiation exposure during refueling outage such as fuel handling, reactor coolant pump maintenance, steam generator inspection and maintenance, reactor vessel head area maintenance, decontamination, and ICI & instrumentation maintenance activities are evaluated at a task level. The calculated value using this method is in close agreement with the value of 0.4 man-Sv, that has been determined based on the experience aid engineering judgement. Therefore, with the As Low As Reasonably Achievable (ALARA) advanced design features incorporated in the design, APR1400 design is to meet its design goal with sufficient margin, that is, more than a factor of two (2), if operated on art eighteen (18) month fuel cycle.

• Archives of Craniofacial Surgery
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• v.18 no.4
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• pp.230-237
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• 2017

Background: The traditional approach for reduction of frontal sinus fractures is coronal incision. Inherent complications of the coronal approach include long scar, hair loss, and long operation time. We describe a simple approach for the reduction of frontal sinus anterior wall fractures using a suprabrow incision that is commonly used for brow lift. Methods: From March 2007 to October 2016, the authors identified patients with anterior wall frontal sinus fractures treated by open reduction through a suprabrow incision. Only cases with photographic/radiographic documentation and a minimum follow-up of 6 months were included. The incision line was designed to be at the upper margin of the eyebrow. Medical records and radiographic data were retrospectively reviewed. Surgical outcomes, cosmetic results, and complication were assessed. The patient scale of the patient and observer scar assessment scale was used to assess patient satisfaction for incisional scar at the 6-month follow-up. Results: Thirty-one patients underwent fracture reduction through a suprabrow approach during the study period, with a mean follow-up of 41 months. No patients showed any recurrent displacement, eyebrow asymmetry, or infection during follow-up. Thirteen patients reported their forehead paresthesia postoperatively, and 12 of them had preoperative symptom. One patient complained of incisional scar and underwent scar revision. All patients were satisfied with their eyebrow and forehead contour. Conclusion: The suprabrow approach allowed for an accurate reduction of the fractures in the anterior wall frontal sinus by providing direct visualization of the fracture. This transcutaneous approach can effectively restore forehead contour with acceptable postoperative complications and patient satisfaction.

• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.44-50
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• 2013

Process gas piping is one of the most basic components frequently used in the refinery and petrochemical plants. Many kinds of by-product gas have been used as fuel in the process plants. In some plants, natural gas is additionally introduced and mixed with the byproduct gas for upgrading the fuel. In this case, safety or design margin of the changed piping system of the plant should be re-evaluated based on a proper design code such as ASME or API codes since internal pressure, temperature and gas compositions are different from the original plant design conditions. In this study, series of piping stress analysis were conducted for a process piping used for transporting the mixed gas of the by-product gas and the natural gas from a mixing drum to a knock-out drum in a refinery plant. The analysed piping section had been actually installed in a domestic industry and needed safety audit since the design condition was changed. Pipe locations of the maximum system stress and displacement were determined, which can be candidate inspection and safety monitoring points during the upcoming operation period. For studying the effects of outside air temperature to safety the additional stress analysis were conducted for various temperatures in $0{\sim}30^{\circ}C$. Effects of the friction coefficient between the pipe and support were also investigated showing a proper choice if the friction coefficient is important. The maximum system stresses were occurred mainly at elbow, tee and support locations, which shows the thermal load contributes considerably to the system stress rather than the internal pressure or the gravity loads.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.2
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• pp.99-105
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• 2011

An integrated model for groundwater flow and radionuclide transport analyses is being developed incorporating six underground silos, an excavated damaged zone (EDZ), and fractured host rock. The model considers each silo as an engineered barrier system (EBS) consisting of a waste zone comprising waste packages and disposal container, a buffer zone, and a concrete lining zone. The EDZ is the disturbed zone adjacent to silos and construction & operation tunnels. The heterogeneity of the fractured rock is represented by a heterogeneous flow field, evaluated from discrete fractures in the fractured host rock. Radionuclide migration through the EBS in silos and the fractured host rock is simulated on the established heterogeneous flow field. The current model enables the optimization of silo design and the quantification of the safety margin in terms of radionuclide release.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.10A
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• pp.780-787
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• 2003

Adaptive modulation is the method to increase the throughput of the mobile system using the power margin of the system design. In this paper, we propose the method to change adaptive modulation parameters for the stable system operation by monitoring the mobility of the mobile station. The proposed method measures the instanteneous mobility of the mobile station monitoring the closed power control data. The MPSK modulation method is used for the basic modulation method because of the hardware implementation. Using the proposed method we can get the more powerful throughput. By the system simulation to verify the evaluation of the proposed algorithm, we can notice the algorithm is more efficient than the typical method

• Korean Journal of Community Nutrition
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• v.8 no.1
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• pp.62-70
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• 2003

This article aims to summarize the development and application of menu engineering technique, 'Menu Engineering Modified by Preference (MEMP)'. The site selected for this project was a foodservice operation in Yonsei University residence hall. Sales and food costs data were collected from the daily sales reports for 1 month, and the survey of food preference was conducted during May, 1999. Statistical data analysis was completed using the SAS/Win 6.12 for descriptive analysis. The calculation for menu analysis were carried out with MS 2000 Excel spreadsheet program. This MEMP technique developed had 6 category criteria and 2 dimensions of the contribution margin (CM) and the menu mix modified% (MMM%) . The MMM% was calculated by the sales volumes and also weighted by food preference. The CM and MMM% for each item were compared with a mean menu CM as well as a 70% rule. Four possible classifications by MEMP were fumed out as 'STAR', 'PLOWHORSE', 'PUZZLE', 'DOG'. 'STAR' items were the most popular and profitable items and required to maintain rigid specifications for quality. The decision actions for 'PLOWHORSE' menu items which were relatively popular, but yield a low menu average CM included combining a plowhorse item with lower cost products and reducing the frequency of serving or serving size. There was a need for 'PUZZLE' items to be changed in the menu combination, improve recipe, and promote menu. The last DOG' items were desired to be deleted. This study demonstrates that menu information can be interpreted more easily with MEMP. The use of MEMP is therefore an effective way to improve management decisions about menu of university residence hall foodservice.

• Journal of Climate Change Research
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• v.4 no.3
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• pp.245-254
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• 2013

Korea government promote renewable energy as the core of their energy matrix to break the dependence and reduce greenhouse effects. This study analyzes the economic assessment of Solid Refuse Fuel project in urban area, considering the marginal external costs of air pollution in this area. Assessment index defined as costs (i.e., construction cost, operation cost) and benefit (margin, external cost) data which is located in Sudokwon landfill site. The result indicates that cost-benefit analysis of SRF is calculated as 1.0. In addition, SRF project is very sensitive about electric power selling price, operating cost and labor cost according to inflation rates. This study shows that the sustainability of SRF project is required the government financial support like investment funds as well as policy support. Variability analysis of SRF economic assessment due to renewable energy can be used for making policies in various fields such as waste and public energy field.