• Korean Journal of Materials Research
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• v.18 no.11
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• pp.623-627
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• 2008

For possible applications as luminescent materials for white-light emission using UV-LEDs, $Ba_2Mg(PO_4)_2:Eu^{2+}$ phosphors were prepared by a solid state reaction. The photoluminescence properties of the phosphor were investigated under ultraviolet ray (UV) excitation. The prepared phosphor powders were characterized to from a single phase of a monoclinic crystalline structure by a powder X-ray diffraction analysis. In the photoluminescence spectra, the $Ba_2Mg(PO_4)_2:Eu^{2+}$ phosphor showed an intense emission band centered at the 584 nm wavelength due to the f-d transition of the $Eu^{2+}$ activator. The optimum concentration of $Eu^{2+}$ activator in the $Ba_2Mg(PO_4)_2$ host, indicating the maximum emission intensity under the excitation of a 395 nm wavelength, was 5 at%. In addition, it was confirmed that the $Eu^{2+}$ ions are substituted at both $Ba^{2+}$ sites in the $Ba_2Mg(PO_4)_2$ crystal. On the other hand, the critical distance of energy transfer between $Eu^{2+}$ ions in the $Ba_2Mg(PO_4)_2$ host was evaluated to be approximately 19.3 A. With increasing temperature, the emission intensity of the $Ba_2Mg(PO_4)_2$:Eu phosphor was considerably decreased and the central wavelength of the emission peak was shifted toward a short wavelength.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.3
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• pp.197-211
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• 2016

Loulan was an ancient kingdom located on the northeast of the Taklamakan Desert, a diverging point between the north and south of Silk Road, on the east of the current Turpan, from the 2nd century BC and the 7th century A.D, absorbing and propagating culture of both sides through active trade. Meanwhile, as many previous research investigations suggest the early trade between Korea and the countries bordering on Western China, characteristics of Loulan costume have been found to have similarity to those of ancient Korean costume. Also, it can be compared to costume in other surrounding regions. Therefore, it is a highly valuable region in researching ancient costume. This study examined the historical background of Loulan and its relationship with ancient Korea, analyzed the clothes found in historic sites of Louland and Niya, and compared costume elements of Loulan and those of Korea. The result of the study shows that first, the Loulan Jeogori was based on the Jikryeonggyoim, with Chaksu, narrow sleeves and the length coming between below the chest and above the bottom, and the line decoration and waist belt were very similar to Korean costumes, as well as the Banryeong, curved collar and Bansu, short sleeves. Second, the types of pants included Gunggo, characterized by closed bottom and many creases, and Daegugo, wide-leg trousers, which are very similar in shape to the Korean Shilla lay sculpture, Stele To Martyr Yi Ch'a-don, Yangjikgongdo and Wangheedo. Third, in accessories as well, the Jowu stuck on the Gwanmo is similar in the shapes to Korean costume.

• Journal of the Korean Institute of Rural Architecture
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• v.17 no.4
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• pp.49-56
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• 2015

This study aims to identify variables (dependent and independent variables) by plane type and area, focusing on the R.C structure planes which were applied to the National Rental Housing Complexes during the 1970-80s; and to investigate differences in residential space compositions depending on the interrelationship between the variables. The results of this study can be summarized as follows: First, an independent variable which had the most influence on the residential space composition was found to be stairs. As dependent variables, bedroom, livingroom, and kitchen showed difference in spatial arrangements. Second, in the case of the front entry type, one-sided arrangements were the most common for the 3L+D.K composition, because livingroom was arranged near the stairs, Disadvantages were: (1) the spatial division of each room was not efficient; and (2) the use of room space was low due to long access to each room. Third, in the case of the rear entry type, no problem was found in arranging bedrooms on the front side. By arranging livingroom as a common space area, the distance of approachability to each room was found to be short and the use of space was excellent. However, disadvantages were: (1) stability was lacking; and (2) privacy was low. Fourth, depending on the location of the stairs, an interaction between bedrooms and the connectivity between livingroom and kitchen were found. Accordingly, there were differences in the size and arrangement of space by plane type.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.100-104
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• 2012

Fin-type SONOS (silicon-oxide-nitride-oxide-silicon) flash memory has emerged as novel devices having superior controls over short channel effects(SCE) than the conventional SONOS flash memory devices. However despite these advantages, these also exhibit undesirable characteristics such as corner effect. Usually, the corner effect deteriorates the performance by increasing the leakage current. In this paper, the corner effect of fin-type SONOS flash memory devices is investigate by 3D Process and device simulation and their electrical characteristics are compared to conventional SONOS devices. The corner effect has been observed in fin-type SONOS device. The reason why the memory characteristic in fin-type SONOS flash memory device is not improved, might be due to existing undesirable effect such as corner effect as well as the mutual interference of electric field in the fin-type structure as reported previously.

• BMB Reports
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• v.30 no.5
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• pp.356-361
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• 1997

We cloned a cDNA (pPRC-1) which was comprised of 841 nucleotides from the cDNA library of a male ICR mouse submandibular gland ($SMG^+$). The nucleotide sequences of pPRC-1 were identical to those of exons 2 and 3 of the mGK-21 gene, a potentially functional glandular kallikrein identified in a Balb/c mouse, except for one nucleotide residue. Although this substitution changes Ile (ATT) in pPRC-1 to Val (GTT) in mGK-21, this difference has been explained by strain polymorphism. From the amino acid sequences predicted from its cDNA, we speculated that mGK-21 gene products/pGK21 consist of 261 amino acids including the $NH_2$-terminal signal peptide (residues 1~17), the short propeptide (residues 17~24), and the active peptide (residues 25~261). Although we did not demonstrate the enzyme activity of pGK21, it was assumed that pGK 21 was involved in the maturation of certain bioactive polypeptide(s) in mouse SMG for the following reasons : (a) mGK-21 gene was apparently expressed in a male ICR mouse SMG: (b) the proposed active site $His^{65}$, $Asp^{120}$, and $Ser^{213}$ residues were completely conserved in pGK21 just like other glandular kallikreins; (c) the cloned cDNA was translated to a predicted 27 kDa polypeptide chain in vitro: (d) the 27 kDa polypeptide chain produced by CHO cells was produced to a putative active form by trypsin.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1547-1556
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• 2009

A novel thermostable $\alpha$-glucosidase (TtGluA) from Thermoanaerobacter tengcongensis MB4 was successfully expressed in E. coli and characterized. The TtgluA gene contained 2,253 bp, which encodes 750 amino acids. The native TtGluA was a trimer with monomer molecular mass of 89 kDa shown by SDS-PAGE. The purified recombinant enzyme showed hydrolytic activity on maltooligosaccharides, p-nitrophenyl-$\alpha$-D-glucopyranide, and dextrin with an exotype cleavage manner. TtGluA showed preference for short-chain maltooligosaccharides and the highest specific activity for maltose of 3.26 units/mg. Maximal activity was observed at $60^{\circ}C$ and pH 5.5. The half-life was 2 h at $60^{\circ}C$. The enzyme showed good tolerance to urea and SDS but was inhibited by Tris. When maltose with the concentration over 50 mM was used as substrate, TtGluA was also capable of catalyzing transglycosylation to produce $\alpha$-1,4-linked maltotriose and $\alpha$-1,6-linked isomaltooligosaccharides. More importantly, TtGluA showed exclusive regiospecificity with high yield to produce $\alpha$-1,6-linked isomaltooligosaccharides when the reaction time extended to more than 10 h.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.413-422
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• 1993

Air shipment affords the quickest possible delivery of horticultural products. The price of air shipped horticultural products are relatively high as most of these products are perishable. Usually the temperature in the cargo compartment is not controlled during flight. Thus, special attention should be paid to procooling prior to shipment. The environmental condition during transportation of horticultural products is an essential parameter for maintaining the quality of perishable products. Commonly horticultural products were loaded by ULD(Unit Load Devices) as a container or pallet in the aircraft (except for small aircraft) . Therefore, inside temperature of the container and cargo compartment came into question. Scarce literature on the relationship between environmental condition and quality changes of horticultural products during air shipment can be found. By the stand point of keeping fresh quality, investigations on the actual condition of air shipments were carried out to improve the technique during the distribution process of fresh horticultural products. Temperature, humidity, atmospheric pressure, carbon dioxide, ethylene, impacts, and changes in quality during the air shipment of snapbeans, okras and chrysanthemums were measured. Temperature was measured by recording thermometers, relative humidity by recording hygrometers, atmospheric pressure by a strain -guage type pressure sensor, carbon dioxide by testing tubes, ethylene by sampling bags and a gaschromatograph, impacts and vibrations by impact recorders and a 3D accelerometer. Relationships between environmental conditions and quality changes during air shipments were clarified. It was expected from investigations into actual shipments that the ventilation and insulation properties of air freight containers were related to the quality of agricultural products. Aircraft can no directly load and unload trucks into them. The transshipment is inclined to cause shocks and vibrations, and to invite damages within a short time.

• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.301-306
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• 1986

Primary pericardial mesothelioma is a rare tumor of mesodermal origin that is infrequently diagnosed antemortem and survival is short. A 60 year old male case of pericardial mesothelioma(epitheloid type) is reported. He was admitted to Yeungnam University Hospital because of chest pain, dyspnea, orthopnea and nonproductive cough. Chest x-ray suggested pericardial effusion, 2-D echocardiography showed echo free spaces of massive pericardial effusion and areas of thick hyperrefractile echoes arising from the pericardium. Pericardiocentesis was attempted and aspirated fluid was bloody exudate. Pericardial window operation with biopsy was done. Swan-Ganz catheterization showed equalization between right atrial pressure and pulmonary capillary wedge pressure. The pathologic diagnosis was established by histologic finding at pericardial biopsy.

• Journal of Korea Technology Innovation Society
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• v.12 no.3
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• pp.545-563
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• 2009

In an era of global competition, international cooperation in science and technology plays a key role in determining a nation's competitiveness. In fact, without international cooperation, it is almost impossible to keep in touch with the fast-changing technology. In regard to this, the Korean government put much efforts into building a strong base for global R&D networking. As a result, the environment for international cooperation has improved a lot. However, the outputs of international cooperation are still poor and fall short of expectations. With the importance of international cooperation in science and technology rising more and more, it is meaningful to examine the current situation of international cooperation in S&T and analyse the outputs of the cooperation activities to review our past and present international cooperation activities. Therefore, this paper focuses on analyzing the outputs of the MEST's international S&T cooperation programs in various ways and recommends ways to improve the outputs of the international cooperation in science and technology.

• Nutritional Sciences
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• v.8 no.3
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• pp.189-195
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• 2005

To assess the effect of pinitol supplementation and strength training for two weeks on the anaerobic capacity during and after exercise, and improvement of glucose metabolism during the recovery period of muscular fatigue with repeated acute bouts of cycling exercise, a total of 24 healthy young men were recruited and randomly and equally divided into three groups; pinitol supplementation group (PSG), placebo group (PLG), and control group (CON). Using a randomized double-blinded design, subjects in PSG were provided pinitol supplement, consumed orally 1.2 g/day, and participated in the resistance exercise program and cycling exercise for two weeks. Subjects in PLG underwent the same protocol as those in PSG but consumed the same amount of placebo. No supplementation and exercise program was given to CON. Before and after the intervention, all subjects were tested for their anaerobic capacities evaluated by Wingate test twice separated by 30 min. During the test, peak anaerobic power (PP), mean anaerobic power, total work, and fatigue index were evaluated During resting and recovery, blood samples were drawn and plasma pinitol, myo-inositol, chiro-inositol, insulin, free fatty acid, glucose, and lactate levels were analyzed After two weeks, PP and relative PP of the second biking were improved from the first biking in PSG only (p<0.05). No changes were found in all other variables of Wingate test in all groups. No statistical differences between groups and pre- and post-intervention were observed in concentrations of pinitol, myo-inositol, and chiro-inositol, but pinitol concentration was higher during recovery compared to the baseline in all groups and testings (p<0.05). Lactate level during recovery was higher than the resting level, but no other blood parameters were significantly changed. In conclusion, two weeks of pinitol supplementation in conjunction with short duration of anaerobic training in healthy young men did not induce any obvious benefits in terms of anaerobic capacity and energy metabolism Individual and/or population susceptibility may be one factor responsible for adopting pinitol supplementation.