• Journal of the Korean Society for Heat Treatment
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• v.9 no.2
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• pp.91-102
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• 1996

Microstructural control to produce multiphase structure has received much attention to improve the high temperature strength as well as low temperature ductility of intermetallics. Transmission electron microscopic investigation has been carried out concerning the effect of Cr-precipitation on the mechanical properties of B2-ordered NiAl containing 4 to 8 mol% of Cr. By aging at temperatures around 973 K after solution annealing, fine spherical precipitates took place homogeneously in the NiAl matrix and the alloys hardened appreciably. Selected area electron diffraction (SAED) patterns have not revealed any additional extra-spots during aging, because the Cr-particles show cube-cube orientation relationship and keep a perfect coherency with the ordered matrix lattice. Dislocations were confirmed to bypass the particles during deformation. Although the dispersion of Cr-particles increased the yield strength of NiAl at intermediate temperature, the strength decreased appreciably at higher temperatures.

• Fashion & Textile Research Journal
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• v.14 no.6
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• pp.1010-1017
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• 2012

This study examined the clothing wearing comfort of elderly women by electroencephalogram (EEG) and electrocardiogram (ECG) analyses. This study utilized 7 elderly individuals aged 65 or more. Two kinds of clothing ensemble (control and prototype) were used as experimental clothing. The control consisted of a general clothing ensemble and the prototype consisted of clothing that added an extra gap. Subjects wore the control or prototype from 9:00 to 21:30 and EEG and ECG signals were measured in the last 30 minutes. The EEG analysis showed that relative band power of a and ${\alpha}$/high ${\beta}$ were higher when they wore the prototype rather than the control. The ECG analysis showed that absolute band power of HF was higher; however, absolute band power of LF and LF/HF was lower when they wore the prototype rather than the control. Subjects felt less stressful and more comfortable when they wore the prototype. The results demonstrate the necessity to develop clothing in consideration of the body changes in elderly women. It is significant that the assessment of wearing comfort was aided by the use of EEG and ECG analysis in the field of clothing and textiles.

• Fashion & Textile Research Journal
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• v.15 no.2
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• pp.277-285
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• 2013

This study examines the wearing comfort of elderly women through a physiological analysis based on rectal temperature and biochemical analysis with salivary melatonin and cortisol. This study was conducted on 7 elderly women aged 65 or over. Two kinds of clothing ensemble (control and prototype) were used as experimental clothing. The control clothing was a general clothing ensemble and the prototype clothing lowered clothing pressure by adding an extra gap. The experimental schedule included daily living activities with randomly assigned experimental clothing. Rectal temperature was constantly measured every 5 minutes during the experiment and saliva samples for melatonin and cortisol were collected twice per day before and after sleep. The rectal temperature was lower for the prototype than the control throughout the experiment, and its circadian rhythm was prompt and clear in prototype. In addition, melatonin was secreted more but cortisol was secreted less when the subjects wore the prototype clothing. With these results, we assumed that regular circadian rhythm and low level of stress might be caused by wearing prototype clothing that lowered clothing pressure. The results demonstrate the necessity to develop clothing that considers body changes in elderly women.

• Korean Institute of Interior Design Journal
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• v.24 no.1
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• pp.43-53
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• 2015

As part of alternative of elderly problems in the future super-aging society, this study aims to extract an improvement plan of interior environment design of Seoul-type day care centers to expand in future by observing day care centers as medical and healing environments, from the perspective of user experience. For this study, after selecting major activity areas of representative cases of Seoul-type day care centers, user behaviors in the space were observed and 4 seniors of baby-boom generation who are potential uses were chosen as personas by reflecting characteristics of healthy elderly, physical aging, mental aging and infirm elderly, from the perspective of user experience. Based on previous studies on healing environments, these characteristics and demands of personas were classified into environmental aspects, physical aspects and mental aspects to extract an improvement plan. The study results are as follows. First, interior environment design reflecting persona characteristics helps the elderly adapt to the environment and provides a comfortable environment like home for stability, treatment and recovery of memory. Second, interior environment design reflecting persona characteristics helps psychological healing through light entering the large windows and natural environment elements. Third, for interior environment design reflecting persona characteristics, finish materials with bright and soft colors should be used to change the images of facilities positively. Fourth, spatial composition should be remedied through division of space and built-in furniture depending on the needs of users for loitering of extra time and programs.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.2
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• pp.201-206
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• 2019

Rejuvenating a system periodically during the most idle time of the system reduces unexpected downtime caused by software aging and increases its availability. In general, software rejuvenation can be largely divided into two broad categories: time-based rejuvenation policy and condition-based rejuvenation policy. In time-based rejuvenation policy the software rejuvenation is triggered at scheduled time epochs with fixed time intervals, while in condition-based rejuvenation policy the software rejuvenation is performed when system state is checked to satisfy a specific condition. Conditionbased policy adds extra cost to the system due to system monitoring and aging estimation. This paper presents a stochastic model for analyzing time-based software rejuvenation mechanism, where the rejuvenation is triggered at scheduled time epochs with fixed time intervals, and provides an analytical solution for the steady-state availability, the user-perceived availability, and the corresponding cost.

• Korean Journal of Metals and Materials
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• v.49 no.2
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• pp.137-144
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• 2011

Strengthening mechanisms in an ordered intermetallic compound containing coherent precipitates of lower antiphase boundary energy than the matrix were investigated on the basis of the interaction between the deformation induced dislocations and the disordered precipitates in an $Ll_2$ ordered $Ni_3Al$-based alloy. Extra work was needed to pull out the dislocations from the precipitate, which was dependent on the difference in the antiphase boundary energy between the matrix and the precipitate, as well as the size and volume fraction of the precipitate. The strength of the $Ll_2$ ordered ${\gamma}^{\prime}$ phase containing fine precipitates of the disordered ${\gamma}$ phase was examined using the proposed model. The model can explain almost quantitatively the age hardening behavior of the $Ll_2$ ordered ${\gamma}^{\prime}$ phase.

• Genomics & Informatics
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• v.17 no.3
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• pp.28.1-28.9
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• 2019

Bar-code (tag) microarrays of yeast gene-deletion collections facilitate the systematic identification of genes required for growth in any condition of interest. Anti-sense strands of amplified bar-codes hybridize with ~10,000 (5,000 each for up-and down-tags) different kinds of sense-strand probes on an array. In this study, we optimized the hybridization processes of an array for fission yeast. Compared to the first version of the array (11 ㎛, 100K) consisting of three sectors with probe pairs (perfect match and mismatch), the second version (11 ㎛, 48K) could represent ~10,000 up-/ down-tags in quadruplicate along with 1,508 negative controls in quadruplicate and a single set of 1,000 unique negative controls at random dispersed positions without mismatch pairs. For PCR, the optimal annealing temperature (maximizing yield and minimizing extra bands) was 58℃ for both tags. Intriguingly, up-tags required 3× higher amounts of blocking oligonucleotides than down-tags. A 1:1 mix ratio between up- and down-tags was satisfactory. A lower temperature (25℃) was optimal for cultivation instead of a normal temperature (30℃) because of extra temperature-sensitive mutants in a subset of the deletion library. Activation of frozen pooled cells for >1 day showed better resolution of intensity than no activation. A tag intensity analysis showed that tag(s) of 4,316 of the 4,526 strains tested were represented at least once; 3,706 strains were represented by both tags, 4,072 strains by up-tags only, and 3,950 strains by down-tags only. The results indicate that this microarray will be a powerful analytical platform for elucidating currently unknown gene functions.

• Korean Journal of Materials Research
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• v.3 no.1
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• pp.43-49
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• 1993

Excellent deep drawability and strain aging rsistance are obtained by the addition of alloying elements such as Ti and Nb which can form carbide and nitride easily into Al killed extra low carbon steel. Recrystallization textures and mechanical properties of the three different extra low carbon steels with B containing Nb only, Ti only, and both Nb and Ti, respectively, along with have been compared. Inverse pole figure shows that (100) and (111) texture intensities of Nb containing steel changed a lot during the annealing treatment and the degree of texture-structural change in the steel containing both Nb and Ti is about the same as that in the Ti-containing 5teel. After annealing the pole figure shows that the {Ill} < 110 > and {112} < 110> textures are the strongest in the cold rolled state and the annealed state, respectively. However, there is little difference in texture structure among the three kinds of steels. There is a tendency that the steel containing both Nb and Ti the grain size of which is the smallest is the highest in hardness. Nb-containing steel is the next and Ti -containing steel is the last in hardness.

• Korean Institute of Interior Design Journal
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• v.23 no.2
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• pp.182-192
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• 2014

Demands for geriatric hospital have increased in an era of rapidly aging population. Most of aged patients tend to stay in institutions for long terms. This means that the patient rooms of geriatric hospital should be given different considerations from those of normal hospital in designing interior features. They should be a homelike places for the aged patients and designed to take care of specific needs of the aged. However, most of geriatric hospitals are designed with little attention to such point. They appear almost same to normal ones. This study attempts to examine how users evaluate patients' rooms. The users are nurses, care-givers and family members of aged patients in six geriatric hospitals in Busan. They rated 12 features of patient rooms from 0 point to 100 points and described reasons why they rated in that way. Also, the walk-through was done for these six hospitals. 12 features are sizes of patient rooms, sizes and fixtures of bathrooms, sizes and locations of windows, bed layout, numbers and types of chairs, sizes and types of closet, lighting, color scheme, finishes of floor and wall, and interior design tone. Followings are findings : The users evaluated patients' rooms relatively positive. However, extra chairs for visitors, closet in patients rooms and storage in bathroom, and sizes of patients rooms and bathrooms were evaluated relatively negative.

• The Korean Journal of Nuclear Medicine
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• v.8 no.1_2
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• pp.25-28
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• 1974

The concentrations of some blood constituents are known to be influenced by the postural change. The blood glucose and insulin concentrations were measured, first, in the supine, and then (30 minutes later) in the erect positions under the Lasting state. The effects of a duretic, furosemide, were also studied under the same condition for 5 consecutive days. The materials were 5 healthy volunteers aging 20-29 years old with out any diabetic past, or family histories. The blood glucose was measured by the Nelson's method, and plasma insulin by the radioimmunoassay method. Following are the results; 1. The plasma insulin concentration in the erect position is slightly higher than in the supine position, however, the increase is statistically insignificant because of the notable individual variations in the values of the supine position. 2. Four cut of 5 cases show the increase of about 80% of plasma insulin in the erect position, which is statistically significant if analyzed on the basis of frequency distribution. 3. The blood glucose concentration showed no postural changes. 4. The increase of the plasma insulin concentration in the erect position seems to be the result of limited extra vasation of insulin in the lower extremities.