• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.6
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• pp.533-541
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• 2020

This study using ABAQUS investigates the nonlinear vibration responses when thermal and random acoustic loads are applied simultaneously to the stiffened composite panels. The nonlinear vibration analyses are performed with changing the number of stiffeners, and layup condition of the skin panel. The panel and stiffeners both are modeled using shell elements. Thermal load (ΔT) is assumed to have the temperature gradient through the thickness direction of the stiffened composite panel. The random acoustic load is represented as stationary white-Gaussian random pressure with zero mean and uniform magnitude over the panels. The thermal postbuckling analysis is conducted using RIKS method, and the nonlinear dynamic analysis is performed using Hilber-HughesTaylor time integration method. When ΔT = 25.18 ℃ and SPL = 105 dB are applied to the stiffened composite panel, the effect of the number of stiffener is investigated, and the snap-through responses are observed for composite panels without stiffeners and with 1 and 3 stiffeners. For investigation of the effect of layup condition of the skin panel, when ΔT = 38.53 ℃ and SPL = 110 dB are applied to the stiffened composite panel, the snap-through responses are shown when the fiber angle of the skin panel is 0°, 30°, and 60°.

• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.2
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• pp.142-148
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• 2006

In this paper, authors propose a novel step-up AC-DC converter operated with power factor correction (PFC) and with high efficiency. The proposed converter behaves with discontinuous current control (DCC) of input current. The input current waveform in the proposed converter is got to be a discontinuous sinusoid form in proportion to magnitude of at input voltage under the constant duty cycle switching. Therefore, the input power factor is nearly unity and the control method is simple. In the general DCC converters, the switching devices are turned-on with the zero current switching (ZCS). But turn-off of the switching devices is done at the maximum current. To achieve a soft switching at turn-off, the proposed converter uses a new partial resonant circuit, which results in the very low switching loss and the high efficiency of converter.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.440-447
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• 2006

This study was aimed at the improvement of the effluent quality of municipal wastewater treatment plant by Oenanthe javanica and Bio-string media. The results were compared with conventional sedimentation tank and pilot sedimentation plant. In this study BOD as organic pollutants, SS, Nitrogen and Phosphorus were tested to evaluate the removal efficiencies for the advanced treatment. The result were as follow: in the Pilot Plant experiment, Tank 2 was fairly high removal efficiency as compared with Tank 1. The removal efficiency of BOD and SS in Tank 2 were as a range of $7.9%{\sim}38.8%,\;14.3%{\sim}60.0%$ and the removal efficiency of T-N, T-P were a range of $9.6%{\sim}31.5%,\;33.0%{\sim}80.0%$ respectively. The removal efficiency of T-P and SS were much higher than BOB and T-N.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.2
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• pp.49-56
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• 2007

MEMS-based storage is being developed as a new storage media. Due to its attractive features such as high-bandwidth, low-power consumption, high-density, and low cost, MEMS storage is anticipated to be used for a wide range of applications from storage for small handhold devices to high capacity mass storage servers. However, MEMS storage has vastly different physical characteristics compared to a traditional disk. First, MEMS storage has thousands of heads that can be activated simultaneously. Second, the media of MEMS storage is a square structure which is different from the platter structure of disks. This paper presents a new request scheduling algorithm for MEMS storage that makes use of the aforementioned characteristics. This new algorithm considers the parallelism of MEMS storage as well as the seek time of requests on the two dimensional square structure. We then extend this algorithm to consider the aging factor so that starvation resistance is improved. Simulation studies show that the proposed algorithms improve the performance of MEMS storage by up to 39.2% in terms of the average response time and 62.4% in terms of starvation resistance compared to the widely acknowledged SPTF (Shortest Positioning Time First) algorithm.

• Atmosphere
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• v.17 no.1
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• pp.87-99
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• 2007

Simulation results of Asian Dust Aerosol Model (ADAM) for the period of April 7-9, 2006 were analyzed, comparing with observed PM10 data. ADAM simulated around ten times lower than on-site PM10 concentration in the source regions: Zhurihe, Tongliao, Yushe, Dalian and Huimin. As the result of this low concentration, transported amounts of Asian Dust were under-estimated as well. In order to quantify a forecasting accuracy, Bias and RMSE were calculated. Even though remarkably negative Biases and high RMSEs were observed, ADAM simulation had followed well up the time of dust outbreak and a transported path. However, the emission process to generate dust from source regions requires a great enhancement. The PM10 concentration at the surface reached up to $2,300{\mu}gm^{-3}$ at Baeknyoungdo and Seoul (Mt. Gwanak), up to $1,750{\mu}gm^{-3}$ at KGAWO about 18:00 LST in April 8, respectively; however, ADAM did not simulate the same result on its second peak. It is considered that traveling Asian dust might have been lagged over the Korean peninsula by the blocking of surface high pressure. Moreover, the current RDAPS's 30 km grid resolution (which ADAM adopts as the meteorological input data) might not adequately represent small-scale atmospheric motions below planetary boundary layer.

• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.45-64
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• 2003

The purpose of this study was to examine the effects of the pelvic tilting exercise, pelvic tilting exercises with floor walking training, pelvic tilting exercises with treadmill walking training on quantitative gait function in patients with hemiplegia. Thirty patients with hemiplegia due to cerebrovascular disease participated in this study. Subjects were randomly assigned to one of pelvic tilting exercise group, pelvic tilting exercise with floor walking training group and pelvic tilting exercises with treadmill walking training group. The effects of each therapeutic method were evaluated by measurements of gait velocity, cadence, stride length, step length, base of support and foot angle using ink-foot prints. Data were analyzed statistically using paired t-test and one-way ANOVA. The results of this research are as followings : 1. After treatment, it turned out that pelvic tilting exercises with treadmill walking training has the most effect on gait velocity, cadence, stride length, step length and foot angle, which has significant difference in statistics (p<0.05). 2. Quantification of the gait velocity, cadence, both stride length and step length demonstrated a significant increase (p<0.05) after treatment in all groups when compared with values measured before treatment. The base of support and foot angle in affected side decreased significantly (p<0.05) after treatment in all groups when compared with values measured before treatment. 3. The lumbosacral angle noted a significant increase (p<0.05) after treatment in all groups, however, an ANOVA analysis did not reveal any differences between groups.

• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.173-188
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• 2003

The two groups each consisting of 28 people who had an adult hemiplegia due to a brain injury received two different methods of exercises to reduce the angle to which the affected lower limb rotates externally. The comparisons between the two groups were made for the changes of the angle in external rotations measured between pre and post test. The static balance index values taken during pre and post tests were also compared. In addition, the correlations of the angle to which the affected lower limb rotates externally with static balance index values were analyzed. The result were as follows: 1. A statistical analysis indicated that in group one having taken simple R.O.M exercises, the angle to which the affected lower limb rotates externally and the static balance index values were both significantly different between pre and post test (P<.01). 2. A statistical analysis indicated that in group two having taken a pattern movement, both the angle to which the affected lower limb rotates externally and static balance index values were significantly different between pre and post test (P<.01). 3. A significant difference between simple R.O.M exercises group and pattern movement exercises groupwas shown only for the angle to which affected limb rotates externally not for static balance index values (P<.01), 4. Pearson correlation coefficient for the angle to which the affected limb rotates externally with static balance index values was found to be significant only in pattern movement exercises group (P < .05).

• Journal of radiological science and technology
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• v.41 no.5
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• pp.427-435
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• 2018

There was a shortage of research reports on sterilization criterion and contamination of ultrasonic probes. Therefore, in this study, we were going to provide a basic study to measure the level of microbial contamination in ultrasonic probes and to investigate the radiographer's awareness of infection. After the scan, samples were collected from the rubber part of the probe by opening a sterile swab (Transport Medium AM608-1S) for medical bacteria collection with the remaining gel removed with a paper towel. Also, the collected samples of bacteria were grown for seven days and then the laboratory was analyzed. Among the total 29 types of microorganisms, Micrococcus luteus 21(26%), Moraxella species 16(20%), Coagulase negative staphylococcus 8(10%), Bacillus species 5(7%), Bicillus circulans 3(5%), Acinetobacter lwoffii 2(2%), and 1 other Candida parapsilosis (1%) a number of bacteria and fungus, was detected. In a disinfectant experiment using LuciPac Pen on the Lumitester PD-30s, we cultured the rubber part of the probe two to three times to measure the bacteria. Bacteria decreased to 97% with Aquanax (alkaline reduced water 100%), 99% with Klarion wash (0.01% sodium hydroxide), 94% with Klarion disinfection (0.01% nitrous acid water), Sterilization was best with Klarion wash (0.01% sodium hydroxide). Therefore, guidelines for cleaning and disinfection of ultrasonic probes was required, and further development of probe-only disinfectants is required.

• Biomedical Science Letters
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• v.7 no.2
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• pp.85-89
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• 2001

Many Staphylococcus aureus strains produce enterotoxins causing food poisoning. Staphylococcal enterotoxins are classified by serological criteria into five major groups - subtype A to E. It is difficult, time-consuming, and expensive to detect staphylococcal enterotoxins in the clinical laboratory. In this study, we fried to detect the enterotoxin genes of Staphylococcus aureus strains isolated from clinical specimens and Kimbap - rice rolled in a sheet of laver - using multiplex PCR technique. A total of 77 strains of Staphylococcus aureus from clinical specimens and 78 strains from Kimbap were isolated. Among clinical isolates of S. aureus, 60 strains (78.0%) were identified as producing enterotoxins. A total offs strains (91.6%) in the 60 staphylococcal enterotoxin producing strains were enterotoxin subtype C. In case of kimbap: 43 (55.1%) strains were detected to produce enterotoxins and 39 (90.6%) enterotoxin producing strains were subtype A.

• Journal of the Korean Society of Costume
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• v.62 no.2
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• pp.40-54
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• 2012

The significance of this research lies in the analysis of that appears in the comedy . It also aims to propose conceptual and analytical costume designs that emphasize the formal aspects of play by reflecting on the comical elements simultaneously. , the subject of this study, was played on November 12, 2009 at the Small Theater (Dalohreum Theater) in the National Theater as a celebration of the 40th anniversary of Suwon Women's College. The costumes were designed by this researcher and were produced in collaboration with the Creative Performances Research Institute (Suwon Women's College). The comic elements were categorized into deconstruction, deviation and unexpectedness according to previous studies on the humorous nature of comedy, and their aesthetic meanings were applied to the costumes. The designs that reflect the comic elements are as follows. The costume design reflecting deconstruction is a way that disassembles and recombines constructive aspects of clothing. It consists of seam margins outside or just left disassembled without sewing, dismantling the boundary of outerwear and underwear. The costume design reflects deviation because reformed shapes of collars, the variation of length and closure of skirts deviate from the traditional style. These are designed by distorting traditional designs with deviation and transcend of tradition. The costume designs the reflect unexpectedness integrates both tradition and the contemporary, and use materials of diversity and heterogeneity, and these are composed of external formats the result from incongruity. Because comic elements are metaphysical concepts that carry meanings that are difficult to define according to the country and period, it is required to analyze, organize and utilize their characteristics and meanings of each period. Since this study analyzed the comical elements of a play and applied them to costume design, it is hoped that a follow-up study of analytical costume design is be done, and that more diverse and more creative costume designs are in the next generation.