• Journal of the Korean Society for Heat Treatment
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• v.18 no.2
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• pp.112-118
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• 2005

Study was focused on the effect of the cooling rate on the embrittlement behavior of Zircaloy-4 cladding simulated Loss Of Coolant Accident (LOCA) environment. Claddings were oxidized at given temperature and given time followed by various water quenching in the range of $0.6^{\circ}C$ and $100^{\circ}C$ per second. Cladding failed after water quenching above the threshold oxidation. Threshold oxidation was decreased as the cooling rate increased, which is due to the matensite structure formed during fast cooling rate.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.6
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• pp.442-446
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• 2003

This paper proposes a new two-stage two-phase VPP charge pump configured in such a manner that body effect and the threshold voltage loss are eliminated. The newly proposed circuit is fabricated using 0.18um triple-well CMOS process and the measurement result shows that the VPP level tracks 3VDD when VDD is above the threshold voltage.

• Laser Solutions
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• v.3 no.3
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• pp.39-45
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• 2000

The volume and depth of the craters produced on silicon samples during high power laser ablation show a strong nonlinear change as the laser irradiance increases across a threshold value, approximately 2.2$\times$10$\^$10/ W/㎠. Time-resolved shadowgraph images of the ablation plume reveal the ejection of large particulates from the sample for laser irradiance above the threshold, with a time delay of about 300-400 ㎱. The numerically estimated thickness of the superheated liquid layer, considering the transformation of liquid metal into liquid dielectric near the critical state, agrees with the measured agrees with crater depths. It is suggested that a phase explosion of the deep superheated liquid layer near the critical state is responsible for the measured sudden increase of crater volume and the ejection of large particulates.

• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.5
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• pp.34-38
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• 1978

In this Paper, the saturation behavior in the electrical phenomena of the DH Laser diode is explained theoretically using rate equnations. The carrier density approaches to ns gradually well above the threshold and theoretically expected curve of and calculated value of $\Delta$Vj are exactly equal to the experimental results which was observed, as shown. The carrier saturation factor If is proposed and we show k$\beta$ is a measure of the ideality of the sample diode. In the light of relation, the sample diode's idoality increases as f decreases.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.141-143
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• 2004

In this present the transient control of SBS chaos induced instability in Brillouin-active fiber systems is described. The inherent optical feedback by the backscattered Stokes wave in optical fiber systems leads to instabilities in the form of optical chaos. At weak power, the nature of the Brillouin instability can occur at before threshold. At strong power, the temporal evolution above threshold is periodic and at higher intensity can become chaotic. Multistable periodic states, makes transition to logic 'on' or 'off'. It can make theoretically potential large memory capacity.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.4160-4176
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• 2015

Data compression like image and video compression has come a long way since the introduction of Compressive Sensing (CS) which compresses sparse signals such as images, videos etc. to very few samples i.e. M < N measurements. At the receiver end, a robust and efficient recovery algorithm estimates the original image or video. Many prominent algorithms solve least squares problem (LSP) iteratively in order to reconstruct the signal hence consuming more processing time. In this paper non-iterative threshold based recovery algorithm (NITRA) is proposed for the recovery of images and videos without solving LSP, claiming reduced complexity and better reconstruction quality. The elapsed time for images and videos using NITRA is in ㎲ range which is 100 times less than other existing algorithms. The peak signal to noise ratio (PSNR) is above 30 dB, structural similarity (SSIM) and structural content (SC) are of 99%.

• Fisheries and Aquatic Sciences
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• v.26 no.8
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• pp.514-523
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• 2023

The visible threshold of Oreochromis niloticus responded to high light intensity under short wavelengths, whereas the response to low light intensity under long wavelengths was low, with a minimum visual threshold of 574 nm of LED lights. Movement distance of O. niloticus was dropped at 31℃ and increased abnormally at 37℃ under natural light. Comparing movement distance under red (622 nm) and green (518 nm) lights of LED, movement distance and swimming speed under red and green lights were higher than under natural light. However, the movement distance decreased rapidly at 31℃ under red light and lowest at 33℃ under green light. After that, there was a tendency to adapt to high water temperatures gradually. Consequently, red and green lights may be recommended for O. niloticus's aquaculture because the red and green lights have a positive effect on growth performance, survival rate, and metabolism, as shown in previous studies. It is necessary to control the water temperature below 32℃ because abnormal behavior above 32℃ revealed under red and green LED lights and natural light.

• Journal of Korean Physical Therapy Science
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• v.2 no.4
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• pp.771-778
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• 1995

The purpose of this study was to determine the effects of linear polarized near-infrared ray radiation on experimental pain threshold in healthy adult subjects. Thirty healthy adult subjects were divided into 5 groups: 1) group 1, super lizer radiation at 0 % ; 2) group 2, super lizer radiation at 10 % ; 3) group 3, super lizer radiation at 20 % ; 4) group 4, super lizer radiation at 40 % ; 5) group 5, super lizer radiation at 80 %. The polarized near-infrared ray radiation was applied on LI 4 point of subject's right hand at a fixed time for 30 second. Experimental pain threshold were measured with electrical current on the right hand at 5 intervals for each radiation: 1) pretreat; 2) posttreat ; 3) posttreat of 1/2 hr ; 4) posttreat of 1 hr ; and 5) posttreat of 2 hrs. Data were analyzed using analyses of variance with repeated measures for pain threshold. No significant interaction between power output and time for pain threshold was found. Significant effects of power output and time for experimental pain threshold were found. Significant increase was noted in experimental pain threshold in group 4 and group 5 at posttreat, posttreat of 1/2, 1 hr and 2 hrs as a result of the applications of the polarized near-infrared ray radiation. This study indicate that polarized near-infrared ray radiation with above 40 % of power output increases pain threshold, thus possibly increasing options in choosing radiation output for treating pateint with pain. Further study is needed to compare the effects of these radiation in patients with clinical pain.

• Journal of Korea Water Resources Association
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• v.40 no.4
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• pp.287-297
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• 2007

The procedures for identifying channel network are suggested by exploring the scaling property between the local slope and the contributing area, given that the area threshold criterion is an indispensable complement to the slope-area threshold criterion. Through the use of the above procedures and the field data, the basin slopes illustrate the trends of large scatters in space for the geomorphologic/topographic factors. According to the scaling regimes of them both the forms of landscape can be classified as topographic divergence and convergence. The presentation of the procedures proposed in this study is implemented in the case study on Seolma experimental catchment in Korea. As a result the dynamic behaviors of basin are confirmed, and thus the dynamics of channel head advance and channel network are shown to represent better than the method using the topographic chart manually.

• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.780-787
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• 2017

The consumption of high-salt foods is an independent risk factor for increased hypertension. Thus, evaluating the relationship of taste sensitivity and pleasantness of high-salt foods such as Korean jang products, would help contribute to an understanding of salty food eating behaviors of the Korean rural elderly. This study aimed to verify the association between taste sensitivity and salinity of Korean jang products, and the preferences of food groups and nutrient intake in the rural elderly. We studied 269 elderly persons (males 83, females 186) aged above 65 years, residing in the rural area, Sunchang gun Jeonbuk. For each subject, a recognition threshold of 4 basic tastes and pleasant concentrations of NaCl were estimated using the sip- and-spit method. Taste preferences, frequency of intake of food groups, nutrient intakes, and salinity and sweetness of Korean jang products (Doenjang, Ganjang, Gochujang) were assessed. No association was found between salt taste recognition threshold and optimally preferred concentration of salt and salinity of Korean jang products. However, the sweet taste recognition threshold was positively related to the sweetness of Korean jang products. Also, the salinity of Doenjang positively correlated with the frequencies of food groups and nutrient intakes. That is to say that the sweet taste sensitivity was related to the sweetness of Korean jang products, but was not sensitive to the salty taste. The salinity of Doenjang correlated with the consumption of food and nutrient intakes. Taken together, these findings suggest the need for appropriate intervention and education to reduce the salinity of Doenjang, which is an important modifiable factor contributing to reducing sodium intake in the rural elderly.