• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.12 no.3
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• pp.1-8
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• 2016

In this study, we evaluated the flow characteristics of various types of waveguide-below-cutoff (WBC) arrays and their shielding effectiveness (SE) of electromagnetic pulses (EMP) based on computational fluid dynamics (CFD). Three types of waveguides were selected for analysis: (1) grid type, (2) honeycomb type, and (3) multi-layer types (2-ply, 4-ply, 6-ply, and 8-ply). To analyze the air flow characteristics, the flow velocities in the longitudinal center of the WBC and the differential pressures between the WBC array inlet and outlet were evaluated. Consequently, we derive the following conclusions: (1) despite an increase in the inlet velocity, the pressure drop of the 6-ply multi-layer type did not significantly increase as compared to that of other types of waveguides (waveguide thickness of 0.1 mm, SE of 100 dB); (2) the grid and honeycomb type had the fastest flow rate of 17.5 m/s, which is approximately 2.5 m/s faster than that at the inlet (waveguide thickness of 1 mm, module size of 30 mm); and (3) the average pressure drop of the grid type waveguide is the lowest in the overall model, whereas that of the 8-ply is the highest (waveguide thickness of 1 mm, module size of 30 mm, and SE of 80, 100 dB).

• Korean Journal of Adult Nursing
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• v.20 no.6
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• pp.950-959
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• 2008

Purpose: The present study was conducted in order to examine claustrophobia, noise sensitivity and vital signs according to anxiety sensitivity level in patients who have Magnet Resonance Imaging(MRI). Methods: With 100 outpatients, we measured anxiety sensitivity, claustrophobia, noise sensitivity and vital sign before and after MRI. Measuring tools were ASI, CLQ-M, and NSI. Data were collected from February to March, 2008. Results: The ASI score was higher in women than in men(p < .05), and no statistically significant difference was observed according to age, region of scanning, experience in MRI, and the use of contrast agent. Both men and women patients showed the same ASI score and decrease in CLQ M and NSI between before and after MRI. In women, ASI, CLQ M and NSI were in positive correlation with one another(p < .001), and in men, there was no correlation between ASI and CLQ M, and positive correlation was observed with NSI(p < .05). In comparison according to ASI level, blood pressure and pulse rate were not different in men and women. CLQ M was not different in men, but was different in women(p < .001). NSI was different in both men and women(men p < .05; women p < .001). Conclusion: MRI may cause claustrophobia in patients with high anxiety sensitivity, and noise appears to aggravate anxiety. In particular, claustrophobia was more serious in women than in men. Therefore, it is necessary to develop nursing interventions to reduce anxiety sensitivity particularly for female patients, and to make plans to educate and lower noise before MRI in order to reduce claustrophobia.

• Korean Journal of Rural Living Science
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• v.7 no.2
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• pp.99-108
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• 1996

This study has intended to suggest fundamental data to develope and choose appropriate shoes for upland farming in order to prevent health deterioration of women workers and improve work effectiveness and reduce fatigue by wearing appropriate shoes. During 1995. 4. 28 - 5. 10, Fifty women workers in hot pepper farming were observed and major shoe types, which were rubber shoes, walking shoes, slippers, and rubber boots, were selected for the study. During 1995. 10. 9 - 31, two subjects were tested by wearing those shoes in the laboratory where the temperature was 24$\pm$1$^{\circ}C$ and relative humidity 50$\pm$5%RH. And the temperature & humidity on sole and in the shoes, the rectal temperature, skin temperature, blood pressure, pulse, lactate concentration of blood, Flickers' value and subjective sensation were measured. The results were as follows : 1. 84% of women workers mentioned that they need shoes improvement and the order of most frequent shoe types to be worn was rubber shoes, walking shoes, slippers, rubber boots. 2. The rate of women who were unsatisfied with shoes for upland farming is 38 percentages. The reason of unsatisfaction was that feet were in a sweat and alien substances were let into shoes. 3. The temperature & humidity on sole were the lowest in rubber boots during experiment(p＜0.01). 4. The relative humidity in the shoes was the highest in rubber boots by 90% and the lowest in walking shoes by 72% during rest And the humidity in slippers and walking shoes were significantly low in experiment(p＜0.001). 5. Rubber boots showed the highest rise in rectal temperature by 0.2$^{\circ}C$ showing increase of core temperature (p＜0.05). 6. The mean skin temperature during experiment was highest in rubber boots by 33.8$^{\circ}C$(p＜0.001).

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.127-130
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• 2004

Lathyrus sativus, locally known as Khesari, is a leguminous pulse crop grown in many parts of the world for food (used by poor people) and animal feed/fodder. Its seeds are rich in protein and energy but contains anti-nutritional factors prominent among which is ${\beta}$-N-Oxalylamino-L-Alanine (BOAA), a neurotoxin causing lathyrism in humans due to prolong consumption. Keeping in view the chemical characteristics of this toxin and literary facts on L. sativus feeding in terrestrial animals, it was hypothesized that aquatic species may better utilise this ingredient in mixed extruded diets. Diets were prepared with varying levels (0, 10, 18, 26 and 34%) of L. sativus seeds and fed for 60 days to study growth, body composition and digestibility of nutrients. Final body weight, specific growth rate and feed and protein conversion ratio did not differ (p>0.05) between treatments. Crude protein digestibility was reduced (p<0.01) beyond 26% inclusion level of L. sativus. Final carcass composition with regard to protein, lipid and ash did not differ (p>0.05) among the treatments. Comparable craniosomatic, viscerosomatic, renosomatic and hepatic indices and no mortality implies no apparent adverse effect on the vital organs and fish health. It was concluded that L. sativus can be a promising feed ingredient that can be used up to 34% or possibly higher level in fingerlings diet. To our knowledge, it appears to be the first report of its kind under laboratory conditions.

• The Journal of the Acoustical Society of Korea
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• v.20 no.5
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• pp.35-47
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• 2001

This paper describes an efficient harmonic-CELP speech coder by taking advantages of harmonic and CELP coders into account. According to frame voicing decision, the proposed harmonic-CELP coder adopts the RP-VSELP coder as a fast CELP in case of an unvoiced frame, or an improved harmonic coder in case of a voiced frame. The proposed coder has main features as follows: simple pitch detection, fast harmonic estimation, variable dimension harmonic vector quantization, perceptual weighting reflecting frequency resolution, fast harmonic synthesis, naturalness control using band voicing, and multi-mode. These features make the proposed coder require very low complexity, compared with HVXC coder To demonstrate the performance of the proposed coder, a 2.4 kbps coder has been implemented and compared with reference coders. From results of informal listening tests, the proposed coder showed good quality while requiring low delay and complexity.

• The Journal of the Acoustical Society of Korea
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• v.37 no.5
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• pp.338-342
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• 2018

In order to solve the floor impact sound problem in the upper and lower floors, the Ministry of Land, Transport and Maritime Affairs also notifies the physical properties of the resilient material affecting the floor impact sound level. The dynamic modulus of elasticity and the loss factor before and after heating are most related to the floor impact noise, especially for the cushioning material. Therefore, in this study, the rate of change with respect to the dynamic modulus and loss factor with temperature change was examined by increasing $10^{\circ}C$ by $10^{\circ}C$ from the temperature condition of $70^{\circ}C$ specified in the standard. The dynamic modulus of elasticity and the loss modulus were measured by using the pulse excitation method for eight kinds of samples. The calculation method was calculated by the time series analysis method using the damped vibration waveform.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.333-336
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• 2001

The transient response in PDFA(Praseodymium-Doped Fiber Amplifier) is theoretically investigated. The PDFA has the spectral gain band in 1.3${\mu}{\textrm}{m}$. The transient model includes the transient buildup of the population inversion, the pump power, and the signal power and their transient variation along the fiber amplifier. The numerical analysis of transient model can predict the gain saturation, the variation of pump power and the gain as a function of the fiber length. It also shows the gain saturation and recovery effects depending on the pumping rate lead to distortion and saturation in the amplification of optical pulse. The results of numerical analysis, for the case of the Pr ion concentration of 1000ppm and the pump power of 0.5W the gain saturation is obtained 30dB at the length of 5m and the saturation time of upper level is 250 $mutextrm{s}$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.67-71
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• 2007

Recently, a health care need according to the increase of an advanced age population is increasing. The requirement about a health care monitoring is increasing rapidly from general people as well as patient. The requisition about a medical treatment technique and a medical treatment information service is the trend to be expanding. That can be possible minimizing the inconvenience of the patient to take a medical service and continuously monitoring the status of the patient to take a health care service. This paper discusses an implementation of wireless physiological signal monitoring system for health care. The system are composed of the sensor node and monitoring program. The sensor node has the physiological signal measurement part and the wireless communication part. The remote monitoring system has a monitoring program that are communicating the sensor node using bluetooth. The sensor node measured the ECG, pulse wave, blood pressure, Sp02, and heart rate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.7189-7195
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• 2015

The method of moments (MoM) is implemented to simulate scattering from a PEC (perfectly electric conductor) cylinder in the TE(transversw electric) EFIE (Electric Field Integral Equation) approach. The procedure expresses the singularity integral and the hypersingularity integral in terms of an analytic function and employs a singularity isolation process coupled with numerical technique along the discretized segment to evaluate the self terms. It is known that, in the MoM technique, the choice of base functions and test functions is very important for the accuracy and convergence of the numerical analysis. Thus, in this paper, three conditions, obtained from the combination of basis functions and test functions, are adopted to get the induced currents on the PEC surface. These currents are compared to the analytical one in the relative rms current error to get the condition that shows fast convergence rate. The fast order of convergence of the current error, 2.528, is obtained under the combination of pulse basis function/delta test function.

• The Korean Journal of Physiology
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• v.25 no.1
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• pp.49-60
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• 1991

The change of the acridine orange absorbance was used to monitor the formation and/or dissipation of a pH gradient in microvillous membrane vesicles (MVV) isolated from human term placenta. Under $Na^+$ efflux conditions, an acidification of the intravesicular space occured and it was completely inhibited by 0.1 mM amiloride. Under $K^+$ efflux conditions, an acidification of the intravesicular space occured and it was potentiated by valinomycin or FCCP. An inwardly directed chloride gradient also induced a minor intravesicular acidification, but it was not observed in voltage-clampled MVV. The initial rate of the dissipation of a pH gradient was accelerated by pulse injections of $Na^+$ in a saturable manner and $Li^+$ could replace $Na^+$. The kinetic parameter of $Na^+$ in placental $Na^+/H^+$ exchange was similar to that of renal $Na^+/H^+$ exchange. Amiloride was a inhibitor of directly coupled $Na^+/H^+$ exchange and its $IC_{50}$ in placental MVV was about 14-fold higher than that in renal brush border membrane. These results indicate that $Na^+/H^+$ exchanger exists in human placental MVV and that its kinetic characteristics is similar to that of renal $Na^+/H^+$ exchanger but its pharmacological characteristics is different. In placental MVV $K^+,\;H^+$, and, relatively minor chloride conductances are present. The magnitude of $Cl^-/OH^-$ exchange, even though it exists, seems to be smaller than that of $Na^+/H^+$ exchange.