• ETRI Journal
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• v.31 no.1
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• pp.68-70
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• 2009

In this letter, a parametric analysis of the Fresnel-field antenna measurement method is performed for a square aperture. As a result, the optimum number of Fresnel fields for one far-field point is guided as $M_{opt}=N_{opt}=D^2/{\lambda}R+5$, where D is the antenna diameter, ${\lambda}$ is the wavelength, and R is the distance between the source antenna and the antenna under test. For the aperture size 5 ${\leq}$ $L_x/{\lambda}$ ${\leq}$ 20, the tolerable distances for gain errors of 0.5 dB and 0.2 dB can be guided as $R_{0.5\;dB}$ ${\approx}$ $1.2Lx/{\lambda}$ and $R_{0.2\;dB}$ ${\approx}$ $2.0L_x/{\lambda}$, where $L_x$ is the lateral length of the square aperture. The tolerable distances for 20 ${\leq}$ $L_x/{\lambda}$ ${\leq}$ 200 are also proposed. This measurement guideline can be fully utilized when performing the Fresnel-field antenna measurement method.

• The Korean Journal of Pain
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• v.24 no.3
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• pp.154-157
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• 2011

Background: Postherpetic neuralgia (PHN) is usually managed pharmacologically. It is not uncommon for patients with chronic kidney disease (CKD) to suffer from PHN. It is difficult to prescribe a sufficient dose of anticonvulsants for intractable pain because of the decreased glomerular filtration rate. If the neural blockade and pulsed radiofrequency ablation provide only short-term amelioration of pain, spinal cord stimulation (SCS) with a low level of evidence may be used only as a last resort. This study was done to evaluate the efficacy of spinal cord stimulation in the treatment of PHN in patients with CKD. Methods: PHN patients with CKD who needed hemo-dialysis who received insufficient relief of pain over a VAS of 8 regardless of the neuropathic medications were eligible for SCS trial. The follow-up period was at least 2 years after permanent implantation. Results: Eleven patients received percutaneous SCS test trial from Jan 2003 to Dec 2007. Four patients had successfully received a permanent SCS implant with their pain being tolerable at a VAS score of less than 3 along with small doses of neuropathic medications. Conclusions: SCS was helpful in managing tolerable pain levels in some PHN patients with CKD along with tolerable neuropathic medications for over 2 years.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.1015-1022
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• 2013

We recently showed that polylysine, the polymer of lysines, retains anti-prion activity. Although the effectiveness of prion inhibition by polylysine was demonstrated with the regimen tolerated in mice, a determination of quantitative polylysine toxicity is necessary to precisely address the in vivo toxicity level of polylysine. In this communication, we report the results of body weight monitoring and hematologic tests performed in CD-1 mice that received two different tolerable dosages of polylysine for an either 5-day or 4-week period. We found that there was no significant alteration in overall serum chemistry, blood cell count, and body weight gain compared with controls. The only notable quantitative change with statistical significance was the decrease of platelet numbers in mice subchronically administered with polylysine. Our results suggest that polylysine is harmless in mice if administered for a short period, but administrations of polylysine in mice may require considerate attention for safety in future investigations as mice chronically receive tolerable doses of polylysine.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.546-549
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• 2004

The T-50/A-50 Golden Eagle was developed for a supersonic trainer and light combat aircraft. At the design stage, vibration control plans were established and applied. For cockpit vibration, crew comfort vibration level was defined by the requirement of MIL-A-8892. It is found that the T-50/A-50 meets the requirement of cockpit vibration from the flight test data analysis. This paper contains the results of cockpit vibration analysis using the flight test data and the results of human vibration analysis lot the pilot inside aircraft. The human vibration level of pilot is increased as dynamic pressure is increased and at the specific high dynamic pressure, the ride comfort indicates 'a little uncomfortable'. Overall analysis results show that the vibration level of T-50/A-50 cockpit is tolerable and not critical for pilot's comfort.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.3
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• pp.1-7
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• 2018

The purpose of this study is to compare and analyze the response time of three mobile portal sites in Korea using distributions. The research subjects are the mobile portal site of Naver, Daum, and Nate. The experiment period is six years from April 18, 2012 when mobile portals started to activate, to April 17, 2018. The number of experiments is 4,060. Histograms and percentages were used for the distribution comparisons. For the theoretical comparison, Chi-Square test is adopted as a parametric method, and Kolmogorov-Smirnov test is as a nonparametric method. Naver was the fastest of all four methods, the next was Nate, the next was the slowest. The same result was obtained in terms of average response speed. These results are in contradiction to the results of the wired portal. Naver is a strategy to increase the response speed in accordance with the characteristics of media. Daum is a strategy to increase the contents at the cost of response speed. As for classification, we divide the response time into "Comfortable", "Tolerable", "Feedback", "Leave" according to response time. The ratio of more than 7 seconds that users leave called as "Leave" is 1.18% for Naver, 11.70% for Daum, and 1.5% for Nate. As Daum is overwhelmingly high, the response time is very much in need of improvement. In addition, we show the response time of three mobile portals needs to be reduced We hope that the results of this paper will facilitate technology competition to increase the response speed of mobile portals.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.509-512
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• 2006

The propellant mixture ratio of gas generator changes when thrust control valve operate to change LRE thrust level. The mixture ratio change of gas generator result in gas temperature change and failure of turbine blade or deterioration of LRE specific impulse. The mixture ratio stabilizer has been developed to maintain propellant mixture ratio of gas generator. This article deals with design and static/dynamic characteristic of stabilizer. Also gas generator system simulation test has shown that the stabilizer can maintain propellant mixture ratio effectively within tolerable range.

• Structural Engineering and Mechanics
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• v.61 no.3
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• pp.427-436
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• 2017

This paper presents an experimental and analytical investigation on the behavior of a U-shaped girder subjected to operation, cracking and ultimate loads. A full-scale destructive test was conducted on a U-shaped girder to study the cracking process, load-carrying capacity, failure mechanism and load-deformation relationships. Accordingly, the tested U-shaped girder was modeled using ANSYS and a non-linear element analysis was conducted. The investigation shows that the U-shaped girder meets the specified requirements of vertical stiffness, cracking and ultimate load capacity. Unfavorable torsional effect is tolerable during operation. However, compared with box girders, the U-shaped girder has a more transverse mechanical effect and longitudinal cracks are apt to occur in the bottom slab.

• Smart Structures and Systems
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• v.20 no.5
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• pp.539-548
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• 2017

Thermoelasticity is a contactless technique for measuring stress distributions in structural elements stressed by dynamic loads. This work describes the characteristics, analyzes the main causes of uncertainty and illustrates a series of operative methods for reducing its effects. More specifically, the effects of the angle of view between the thermographic camera and the surface of the object are studied, along with those due to the heat transmission by conduction between the various parts of the thing being measured as a function of the stress frequencies. The analyses, both theoretical and experimental, are aimed at defining the operational limits and optimal measurement and test conditions in relation to the measurement uncertainty that is considered tolerable in the specific application.

• Journal of Nutrition and Health
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• v.27 no.4
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• pp.356-367
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• 1994

The purpose of this study was to investigate the dietary compliance and related variables in NIDDM patients. One hundred and fourteen patients at two hospitals in Seoul were interviewed and height, body weight, family history and postprandial blood glucose were analyzed statistically along with the dietary practices. 1) When the degree of dietary compliance was expressed as Tunbridge score, 75% was grouped as satisfactory, 9.7% as Tolerable, and 14.9% belonged to Hopeless group. 2) Calorie intake of the subjects was lower then RDA. Carbohydrate, fat, and protein contributed each 60 : 22 :18. When SFA was used 1, the relative ratio of PUFA : MUFA : SFA was 0.8 : 1.2 : 1. 3) The mean score of knowledge test on diet therapy was 5.6$\pm$2.9 out of possible 12.0 points. 4) Age had significant positive correlation with duration of diabetes(p<0.001), and significant negative correlation with scores of knowledge test on diet therapy was observed(p<0.001). 5) The difference of actual and prescribed calorie intake had positive correlation with PP2 blood glucose level(p<0.05), and significant negative correlation with age(p<0.05). 6) Statiscally significant variables on the practice of diet therapy were the present body weight, protein and carbohydrate intake, age, and sex.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.1396-1404
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• 2012

A composite pile consisted of a concrete lower part with a steel tubular pile at upper part was installed by pre-drilling method. Seven pairs of strain gauges and inclinometer were attached on the pile in order to measure stresses and displacement along the pile during the lateral loading test. The results of instrumentation were analyzed using various theoretical approaches. The back analysis showed that the measured stresses were smaller than those of the calculated. The maximum stress is measured at the steel upper part and decreased rapidly with depth of the pile. The calculated lateral displacement along the pile provide very good agreement with the measured values if the coefficient of subgrade reaction is selected properly. The design concept of a composite pile is verified by the measured stresses and displacement which is within the tolerable limits of the pile.