• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1277-1279
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• 1994

In the structure of ZnO/nip-SiC: H/metal substrate amorphous silicon (a-Si:H) solar cells, the effects of inserting a rear textured ZnO in the p-SiC:H/metal interface and a graded bandgap buffer layer in the i/p-SiC:H have been analysed by computer simulation. The incident light was taken to have an intensity of $100mW/cm^2$(AM-1). The thickness of the a-Si:H n, ${\delta}$-doped a-SiC:H p, and buffer layers was assumed to be $200{\AA},\;66{\AA}$, and $80{\AA}$, respectively. The scattering coefficients of the front and back ZnO were taken to be 0.2 and 0.7, respectively. Inserting the rear buffer layer significantly increases the open circuit voltage($V_{oc}$) due to reduction of the i/p interface recombination rate. The use of textured ZnO markedly improves collection efficiency in the long wavelengths( above ${\sim}550nm$ ) by back scattering and light confinement effects, resulting in dramatic enhancement of the short circuit current density($J_{sc}$). By using the rear buffer and textured ZnO, the i-layer thickness of the ceil for obtaining the maximum efficiency becomes thinner(${\sim}2500{\AA}$). From these results, it is concluded that the use of textured ZnO and buffer layer at the backside of the ceil is very effective for enhancing the conversion efficiency and reducing the degradation of a-Si:H pin-type solar cells.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.70
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• pp.39-65
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• 2016

On 2013 the English court delivered a decision that the payment obligation under time charter party is a condition. According to this judgement, The Astra, a breach of the obligation to pay hire on time entitles the owner both to withdraw the ship and sue the charterers for damages for the difference between the contract and market rate for the remainder of the contracted period. On 2015, however, the English court stood at the other side. In Spar Shipping, the court confirmed that the obligation to pay hire is not a condition of the contract but an "innominate term" - from the charterers' breach ship owners can exercise their contractual right to withdraw, but owners' right to sue for damages depends on whether the charterers have deprived the owners of the substantial benefit of the contract, or shown an intention to do so. This article aims to compare both decisions over the points that (1) the importance of on-time payment under a time charter party, (2) as a critical and main question in this article, whether the mattered payment clause is a condition or innominate term, (3) whether the on-time payment clause is merely a penalty or a reasonable liquidated damage. Based on various reasons, I am on a position that the payment of hire is not a condition but an innominate term. Default in punctual payment by a charterer, in the absent of clear contractual agreement, needs to be decided further whether that breach removes the substantial benefit of the contract from the owners.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.1
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• pp.19-27
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• 1999

Apoptosis has been implicated in the pathophysiological mechanisms of various neurodegenerative diseases. In a variety of cell types, oxidative stress has been demonstrated to play an important role in the apoptotic cell death. However, the exact mechanism of oxidative stress-induced apoptosis in neuronal cells is not known. In this study, we induced oxidative stress in IMR-32 human neuroblastoma cells with tert- butylhydroperoxide (TBHP), which was confirmed by significantly reduced glutathione content and glutathione reductase activity, and increased glutathione peroxidase activity. TBHP induced decrease in cell viability and increase in DNA fragmentation, a hallmark of apoptosis, in a dose-dependent manner. TBHP also induced a sustained increase in intracellular $Ca^{2+}$ concentration, which was completely prevented either by EGTA, an extracellular $Ca^{2+}$ chelator or by flufenamic acid (FA), a non-selective cation channel (NSCC) blocker. These results indicate that the TBHP-induced intracellular $Ca^{2+}$ increase may be due to $Ca^{2+}$ influx through the activation of NSCCs. In addition, treatment with either an intracellular $Ca^{2+}$ chelator (BAPTA/AM) or FA significantly suppressed the TBHP-induced apoptosis. Moreover, TBHP increased the expression of p53 gene but decreased c-myc gene expression. Taken together, these results suggest that the oxidative stress-induced apoptosis in neuronal cells may be mediated through the activation of intracellular $Ca^{2+}$ signals and altered expression of p53 and c-myc.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.3
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• pp.321-328
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• 1999

Pulmonary blood vessels with diameters of $200{\sim}400\;{\mu}m$ produce considerably more force in response to vasoconstrictor drugs than those which are either smaller or larger. We have therefore investigated whether or not hypoxic pulmonary vasoconstriction (HPV) is more powerful in vessels of these diameters. We have also looked at the possibility that vessels from different regions of the lung respond differently. To do this we have grouped vessels according to their location within the lung as well as by size. We used a small vessel myograph (Cambustion AM10, Cambridge, UK) to study 208 preconstricted $(1\;{\mu}M\;PGF_{2{\alpha}})$ small pulmonary arteries $(300{\sim}800\;{\mu}m$ diameter when stretched to a tension equivalent to 25 mmHg transmural pressure) from 39 rats anaesthetized with 2% inspired halothane. A biphasic contraction was observed in response to hypoxia (ca. 25 mmHg $Po_2).$ The magnitudes of both the first, transient, phase (PT, peak tension) and of the second, sustained, phase (SST, steady state tension) were measured. The latter was measured 40 min after the start of hypoxia. The first phase was most pronounced in vessels with an average diameter of 423 ${\mu}m$ while the second phase was most pronounced in larger vessels (mean diameter 505 ${\mu}m).$ These maximal responses were all seen in vessels somewhat larger than reported by others. The responses of smaller vessels $(400{\sim}500\;{\mu}m)$ did not depend upon their location within the lung, but those of larger vessels $(600{\sim}700\;{\mu}m)$ showed regional differences. Those from the right lobe and those from the base of the lung gave the largest responses. It was especially noticeable that large vessels (631 ${\mu}m$ diameter) from the base of the right lung gave the biggest responses. Thus HPV seems to occur not in a uniform manner, dependent solely to the size of vessels, but it also depends to some degree on the region of the lung from which vessels have been taken. Furthermore, our results suggest that larger vessels, as well as smaller ones, may contribute significantly to HPV.

• Restorative Dentistry and Endodontics
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• v.24 no.4
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• pp.639-646
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• 1999

The dental care delivery system and the dental specialty system have a very close relationship each other. Compared to Korea. Western European countries with predominant public sector in dental service have recognized merely 2 or 3 dental specialties, while North American countries with predominant private sector, 8 or 9 ones. It is desirable to adopt the dental specialty system as soon as possible in Korea to encourage scientific development in various dental specialties and qualitative advance in dental service. We, however, have to establish equitable dental care delivery system which can use limited dental resources efficiently as follows. 1. clarifying the different roles in assignments between general dentists and specialists by the amendment of the related laws such as the Medical Act and establishing the organic patient-referral system. 2. adopting the dental specialty system and expanding personnel and equipments so that the dental college hospitals, especially dental divisions of general hospitals, night function as secondary care facilities with specialties. 3. determining the size of dental specialists according to the national needs for dental specialized service's, whose number is to be not more than 10% of the total dentists. 4. transferring the function of accredating dental specialists to the efficient, self-controlled professional organization such as the Korean Dental Association rather than putting it under the governmental control. 5. conducting a comprehensive review of specialty education and practice for re-recognition, and maintaining competence of specialists by re-accredating them periodically. I expect this article to contribute to further discussion about the dental specialty system in Korea in productive and practical way. I am sure that we can Establish this system in the near future when people in every walks of life-the academic circle, the press, the authority concerned, consumer groups and the Korean Dental Association-take part in the discussion with special concern.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.225-232
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• 1999

Apo E polymorphism(e2, e3, e4) was among the first reported genetic polymorphism that explained part of the normal variation in plasma cholesterol concentrations. Among 62 normolipidemic healthy females, aged 19 up to 22 years, the relative frequencies of E3/3 was 0.806(n=50), E3/2 was 0.081(n=5), E3/4 allele was 0.113(n=7), and no E2/2, E2/4 and E4/4 were found. Based on the five samples of E2 allele, five subjects were randomly selected by E3 and E4 groups for the study of effects of apo E polymorphism on the distribution of serum lipid and amino acids profiles. No differences in the anthro pometric data among apo E isomers were found, otherwise the pulsation was higher in E4 than that in the others. There were no differences in plasma total HDL , HDL3 , HDL2 & LDL cholesterol, and apo A I concentrations. However, phenotype means significantly rank E2>E3>E4 allele in average TG levels(p=0.014), and rank E4>E3>E2 in total cholesterol levels(p=0.011). Atherogenic index(AI) such as lipoproteins was significantly increased in E2 & E4 than that in E3(p=0.045). Subjects with E3/2 allele had significantly higher concentrations of glutamine, phosphoserine and taurine, while subjects with E3/4 allele showed significantly lower concentrations of arginine and am inobutyrate and elevated level of phosphoserine in plasma com pared to those of E3/3 allele. Higher level of plasma taurine in subjects with E3/2 or E3/4 allele appears to be related to the elevated level of plasma total and LDL cholesterol concentrations compared to those of E3/3 allele.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.539-547
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• 2009

This study was conducted to investigate the arbuscular mycorrhizal fungal biodiversity, spore density and root colonization in relation to site ages at expressway cut-slopes in Korea. Stabilization of exposed surface involved soil amendments and spraying seed mixture of turf grasses and/or nitrogen-fixing shrub species. Eighteen sites were selected with varying ages (2 to 16 years). Soil samples collected in October from each site were analyzed for fungal diversity and spore counts. Fine root samples from the plants were assayed for fungal colonization. Of the total 37 plants inspected in the sites, 26 species had endomycorrhizal colonization with an average root colonization rate of 18%, and with a range from 1 to 67%. The average endomycorrhizal colonization rate of initially introduced Festuca arundinacea which became the most dominant grass in later stage showed 22.8%, while that of Lespedeza bicolor which became the most dominant woody species were 21.6%. Naturally-invading Robinia pseudoacacia showed higher colonization rate in the old sites. Although site age did not show significant effects on fungal diversity, the root colonization rates of initially introduced plants decreased with the site aging, while those of invading plants increased with aging of the sites. The soil chemical properties, pH, N, and P contents, were negatively correlated with spore density, root colonization and endomycorrhizal species diversity. A total of forty arbuscular mycorrhizal fungal species in seven genera were identified. Of the 40 species, Acaulospora lacunosa, Glomus aggregatum, Glomus constrictum, Scutellospora erythropa, and Acaulospora spinosa were the five most dominant species in the decreasing order.

• Journal of Electrochemical Science and Technology
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• v.2 no.4
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• pp.187-192
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• 2011

Photoelectrochemical performances of ZnO electrodes are enhanced by coupling with cobalt-based catalyst (CoPi) in phosphate electrolyte (pH 7). For this study, hexagonal pillar-shaped ZnO nanorods are grown on ZnO electrodes through a chemical bath deposition, onto which CoPi is deposited with different photodeposition times (10-30 min). A scanning electron microscopic study indicates that CoPi deposition does not induce any change of ZnO morphology and an energy-dispersive X-ray spectroscopic analysis shows that inorganic phosphate ions (Pi) exist on ZnO surface. Bare ZnO electrodes generate the current of ca. $0.36mA/cm^2$ at a bias potential of 0.5 V vs. SCE, whereas ZnO/CoPi (deposited for 10 min) has ca. 50%-enhanced current ($0.54mW/cm^2$) under irradiation of AM 1.5G-light ($400mW/cm^2$). The excess loading of CoPi on ZnO results in decrease of photocurrents as compared to bare ZnO likely due to limited electrolyte access to ZnO and/or CoPi-mediated recombination of photogenerated charge carriers. The primary role of CoPi is speculated to trap the photogenerated holes and thereby oxidize water into molecular oxygen via an intervalency cycle among Co(II), Co(III), and Co(IV).

• Journal of Oriental Medical Thermology
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• v.3 no.1
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• pp.27-35
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• 2004

Today, everybody lives in the stress. So 50% to 80% or 60% to 80% of the modern diseases are estimated what is caused by the stress. And one of the most important point of the stress is a too serious and continuos tension state. Therefore the best way to promotion, persistence, prevention and treatment of the modern man's health will be the relaxion from the tension state. The relax therapy as known as am effective method to the disease which as concerned with stress. that can be adapted to the treatment of anxiety-related diseases, insomnia, hypertension, tension headache, migraine, asthma, preparation of delivery, G-I disorders and menstrual disorders. Until now we guess the change of a relaxed state by the observation to the change of autonomic nervous system(ANS) and EEG. From the point of the ANS, sympathetic nervous system progresses slowly but parasympathetic nervous system increases the activity. In the EEG, both the alpha-wave concerned with the deep physical relaxed state and emotional stability and the theta-wave appeared in the state of meditation are increased. Current studies show that among the biochemical changes, especially serotinin like body hormone is increased by the feeling of the stability or the happiness. So, to see the change of the relaxed state in the image of the D.I.T.I., we used the deviational differences between the pre-relaxed state and the post-relaxed state of 70 people. As a result, the portional deviation of the face is decreased in the image of the D.I.T.I. So it can be thaught that we can determine the changes of the relaxed state by the D.I.T.I.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.279-292
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• 2012

This study was performed to investigate the quality characteristics and antioxidant activity of noodle added freeze-dried purple sweet potato powder. For Hunter's color resulted, as the amount of purple sweet potato powder increased, L-value and b-value decreased, the a-value increased. Anthocyanin contents of purple sweet potato powder at concentration of (mg/100 g) were 99.62%. DPPH radical scavenging activities of purple swe et potato powder at concentration of $1,000{\mu}L/mL$ were 84.60%. The texture of cooked noodles appeared no significant differences in cohesiveness, Springiness, Hardness, Gumminess and Chewiness decreased as the am ount of purple sweet potato powder increased. The weight, volume, moisture contents of noodles were not significantly. Sensory evaluation of acceptability including color, aroma, taste, chewiness and overall-acceptabi lity appeared the 6% added group was the best for higher. According to the positively evaluated anthocyanin content, DPPH radical scavenging activities, quality characteristics and sensory evaluation, a purple sweet pota to powder content 6% appears to be most appropriate.