• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.165_166
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• 2009

A HTS(High Temperature Superconductor) Cable is regarded as the most underground power to respond higher power density delivery system. This paper discussed electrical characteristic and standards of HTS Cable system. Various HTS cable characteristics are examined[3-5], ad compared with XLPE cable characteristics on possible distribution system environment. HTS cable is required to stabilize thermal condition for superconducting status, possible improper operating condition which affects quench, unbalanced, and harmonics impacts are discussed. HTS cable is customer designed cable which shall be implemented in special requirement of power system, the standard origination process requires to establish a series of methodology including design manufacturing, testing and installation.

• Journal of Microbiology and Biotechnology
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• v.4 no.1
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• pp.1-6
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• 1994

Continuous culture was carried out with a recombinant Escherichia coli W3110/pCR185, which encodes trp-operon enzymes when the temperature is shifted from $37^{circ}C\;t;42^{\circ}C$. Under derepressed condition of $42^{\circ}C$. plasmlid stability and gene expression were analysed as function of the dilution rate. The stability of plasmid increased with the dilution rate, but maximal levels of gene expression (tryptophan concentration) and plasmid DNA content were obtained at the lowest dilution rate, $0.075\;hr^{-1}$. The plasmid instability, observed at low dilution rates, could be explained by the unbalanced biosynthetic state of the recombinant cell harboring a high copy number of plasmid.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.189-1-190-1
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• 2008

A high temperature superconducting(HTS) power cable is available for high capacity current in normal condition. But resistance was appeared to operate unbalance load by thermal current characteristic. This characteristic of HTS power cable used to design for unstated condition. And than, It used to understand and analyze characteristic of power cable thermal and critical current. This study appeared that quench resistance reason from shield and former current rise to superconductor(SC) current. The resistance of SC occurred that the cable temperature rise to fault current after decreased critical current. The quench resistance of SC increased in temperature or decreased in critical current. So the quench resistance of SC correlated with resistance of both shield and former current. It need to sufficiently influenced the parameters of HTS cable design.

• Journal of the Korean Statistical Society
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• v.32 no.3
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• pp.245-259
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• 2003

The 2-way balanced one-level rotation design has been discussed (Park et al., 2001), where the 2-way balancing is done on interview time in monthly sample and rotation group. We extend it to 3-way balanced multi-level design to obtain more information of the same sample unit for one or more previous months. The 3-way balancing is accomplished not only on interview time in monthly sample and rotation group but also on recall time as well. The 3-way balancing eliminates or reduces any bias arising from unbalanced interview time, rotation group and recall time, and all rotation groups are equally represented in the monthly sample. We present the rule and rotation algorithm which guarantee the 3-way balancing. In particular, we specify the necessary and sufficient condition for the 3-way balanced multi-level rotation design.

• Transactions of the Korean Society of Mechanical Engineers
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• v.8 no.3
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• pp.224-231
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• 1984

Having found by means of a tension-shear test an optimal spot welding condition under which the maximum weld strength is to be brought forth, this study made an examination of behavior of fracture concerned with behavior of stress distribution, observed around the nugget periphery of the specimens prepared under the optimal conditions, with one point spot welded mild steel sheets. The resultant findings are as follows: (1)There remarkably exists an optimal spot welding condition to indicate the maximum weld strength, and fracture of the specimens spot welded under that condition occurs outside the nugget boundary. (2)An experiment on the basis of a photoelastic model reveals that the maximum stress is distributed along the center line of the steel plate width but occurs on the region corresponding to heat affected zone of spot welds. (3)Heat affected zone of spot welds consists of coarse grains with considerably low micro Vickers hardness value and of fine grains of high micro Vickers hardness value, and in this unbalanced structure weak region are represented in coarse grain region, where fracture is initiated and continues its propagation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.11
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• pp.1051-1059
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• 2004

Two phase thermosyphone loop for electronics cooling are designed and manufactured to test its performance under the partial load and low environment temperature conditions. The thermosyphone device has six evaporators connected parallel for the purpose of cooling six power amplifier units (PAU) independently. The heater modules for simulating PAUs are adhered with thermal pad to the evaporator plates to reduce the contact resistance. There are unbalanced distributions of liquid refrigerant in the differently heated evaporators due to the vapor pressure difference. To reduce the vapor pressure differences caused by partial heating, two evaporators are connected each other using the copper tube. The pressure regulation tube successfully reduces these unbalances and it is good candidates for a field distributed systems. Under the low environment temperature operating condition, such as $-30^{\circ}C$, there may be unexpected subcooling in condenser. It leads the very low saturation pressure, and under this condition there exists explosive boiling in evaporator. The abrupt pressure rise due to the explosive boiling inhibits the supplement of liquid refrigerant to the evaporator for continuous cooling. Finally the cooling cycle will be broken. For the normal circulation of refrigerant there may be an optimum cooling air flow rate in condenser to adjust the given heat load.

• Journal of the Korean Home Economics Association
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• v.36 no.7
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• pp.25-38
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• 1998

This research was carried out to investigate the health condition, eating behavior and nutritional status of female high school students. The survey was conducted from July 5 to July 18, 1996 with 524 first grade students(15 to 17 years old) of H girl's high school using the questionnaire method. The levels of depression and anxiety were measured by CED-S and Spielburger's STAI-S, respectively. In addition, nutrient intakes were estimated by Convenience Method. The results of this study are as follows: 1. The mean depression and anxiety scores of the subjects were 22.23 and 26.00, respectively. The proportion of subjects with normal weight(BM) was 72.1%. The perceived health condition of subjects was moderate and 15.1% of subjects were anemic. The subjectiv health symptoms were feeling drowsy, tired eyesight, getting tired easily, catching cold frequently and frequent headache. 2. The irregularity of breakfast was high in the subjects. The problems of the eating behavior were irregular meals, unbalanced diets, excessive meals, skipping meals and food prejudice. Forty-nine percent of subjects had good eating behaviors. 3. The mean energy intake of subjects was 1717Kcal. The proportion of energy derived from carbohydrates, proteins and fats were 62.70%, 13.89% and 23.42%, respectively. The subjects consumed 59.59g of protein, 13.07mg iron, 637.49mg calcium, 553.64 R.E. vitamin A, 0.94mg vitamin B1, 1.08mg vitamin B2, 15.15mg niacin and 49.59mg vitamin C, respectively. Except niacin, other nutrient intakes were less than the Korean recommended dietary allowances(RDA), especially, iron. 4. Mother's occupation, subject's pocket money and perceived health condition were negatively correlated with eating behavior, And the depression and anxiety of subjects showed wrong eating behaviors. The effects of socioeconomic variables, depression, anxiety and perceived health condition on the nutrient intake were different depending on the kind of nutrient. The nutrient intakes differed significantly among the group of different eating behavior. The eating behavior was significantly correlated with the nutrient intake.

• Korean Journal of Health Education and Promotion
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• v.12 no.1
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• pp.111-127
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• 1995

This study was designed to investigate the relationships between children's physical growth and health and their raising conditions and to find out the important conditions to improve their physical growth and health. The rasing conditions were classified into three major parts; i. e., family conditions, conditions of nutrition up-taking, and conditions of rest or sleep and exercise or play. Then, the questionnaire including the items to survey these three areas of raising condition and the items to evaluate the health status were given to children' mothers or fathers and filled up by them. The data of their 4 anthropometric measures; body weight, stature, sitting height and chest girth, were also collected from their latest records of health examination. The data of health status were converted to health scores representing 6 domains of health; digestive organs, respiratory organs, auto-nerve systems, fatigue, others and health as a whole. Then, correlations of raising conditions were determined with four antropometric measures and 6 health scores as criterion variables. Then, number of families to live together, and child's birth order in the domain of family conditions, habits of unbalanced diet, eating frequency of eggs, fruits, green and yellow vegetables, light colored vegetables, milk products in the domain of nutrition up-take, and the time for study at home, the place for play, the number of friends to play with together, the hours for playing out of door, the hours for playing sports, and the hours to move their body for assisting house keeping were picked out to investigate their relationships with physical growth and health status. Then, their habits of unbalanced diet and eating frequency of eggs, green or yellow colored vegetables, and milk products were found more influential conditions and more over, birth order, the time for study at home, the time to play out of door showed moderate degree of connection with physical growth and health status in early childhood.

• Journal of the Korean Ceramic Society
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• v.49 no.6
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• pp.620-624
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• 2012

The role of moisture remaining inside the deposition chamber during the formation of the cubic boron nitride (c-BN) phase in BN film was investigated. BN films were deposited by an unbalanced magnetron sputtering (UBM) method. Single-crystal (001) Si wafers were used as substrates. A hexagonal boron nitride (h-BN) target was used as a sputter target which was connected to a 13.56 MHz radiofrequency electric power source at 400 W. The substrate was biased at -60 V using a 200 kHz high-frequency power supply. The deposition pressure was 0.27 Pa with a flow of Ar 18 sccm - $N_2$ 2 sccm mixed gas. The inside of the deposition chamber was maintained at a moisture level of 65% during the initial stage. The effects of the evacuation time, duration time of heating the substrate holder at $250^{\circ}C$ as well as the plasma treatment on the inside chamber wall on the formation of c-BN were studied. The effects of heating as well as the plasma treatment very effectively eliminated the moisture adsorbed on the chamber wall. A pre-deposition condition for the stable and repeatable deposition of c-BN is suggested.

• Journal of Surface Science and Engineering
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• v.54 no.3
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• pp.102-111
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• 2021

The corrosion behaviors of laser-welded super duplex stainless steel tubes with post-weld heat treatment(PWHT) conditions(950, 1000, 1050, 1100 ℃ for 5 and 30 min) were evaluated by electrochemical potentiodynamic polarization and critical pitting temperature measurements. This study showed that the critical metallurgical factors affecting the degradation of corrosion resistance of a steel tube in as-welded condition were the unbalanced phase fraction(ferrite:austenite = 94:4), Cr₂N precipitation, and phase transformation from the austenite phase to ɛ-martensite(via stress-induced phase transformation). The improvement in the corrosion resistance of the welded specimen depends greatly on the PWHT conditions. The specimens after PWHT conducted below 1000 ℃ showed inferior corrosion resistance, caused by precipitation of the sigma phase enriched with Cr and Mo. At 1100 ℃ for a longer duration in PWHT, the ferrite phase grows, and its fraction increases, leading to an unbalanced phase fraction in the microstructure. As a result, pitting can be initiated primarily at the interface between the ferrite/austenite phase, particularly in base metal.