• Asia pacific journal of information systems
• /
• v.17 no.2
• /
• pp.29-47
• /
• 2007

Owing to the rapid growth of using the Internet, not only click-and-mortar companies but also brick-and-mortar ones have been expanding their distribution channels into online, Moreover, since online channels are more attractive than offline ones in control and maintenance, switching customers into online ones is emerged as one of very important managerial issues in a view of reduction of cost as well as expansion of services. However, the switched customers should be faced by uncertainties which could not have been experienced in offline. Specifically, in online channels, buyers and sellers are separated temporally and spacially and there are always so many kinds of threat for security as well as not enough systems and conventions for them yet. Therefore, trust has been considered as one of the most critical mechanisms for resolution of such uncertainties in online transactions. However, it is not easy to build and maintain the relationships in online since most of them are virtual and indirect generally. Therefore, in order to switch offline customers into online ones, it is very important to make strategies based on identification of the relationship between online transaction and offline trust which has been built in offline business. Generally offline trust, which has been built independent of online, could not include trust for online-dependent activities such as payment security during or after transactions, while most of online trust include it. Therefore, a customer with high offline trust does not always perceive high security and assure safe transactions. Accordingly, while online trust, where technical capabilities for online security is one of main bases, includes control trust implicitly or explicitly, offline trust does not. However. in spite of such clear discrimination and independence between offline trust and perceived security, there can be the significant dependency between these two beliefs. The customers with high offline trust believe that the company would do some activities for online security for customers' safe transactions since it has been believed of doing well for customers' trust. Theoretically, users' perception of security is interpreted as a kind of control trus, which is trust for company's technical control capacities in order to resolve technical uncertainties in online. Therefore, the relationship between two beliefs can be considered as transference from offline trust to another type trust. that is, control trust. The objective of this study is to analyze the effect of offline trust on online transaction uses mediated by perceived security. For this purpose, we suggest a research model based on technology acceptance model (TAM). Reuse intention is adopted as a dependent variable and TAM is modified by adding perceived risk (PR) as well as two beliefs of using Internet banking, perceived usefulness (PU) and perceived ease of use (PEOU). Moreover, perceive security (PS) is adopted as an external variable for PR and PU, while offline trust (OT) is an antecedent of PS. For an empirical test, sampling from 108 visitors to the banks in Daegu, Korea, we analyze our model by partial least square (PLS) approach. In result, our model is shown to explain 51.4% of the variance in reuse intention and all hypothesis are supported statistically. A theoretical implication of this study is to identify a role of PS between offline trust and reuse intention of using online transaction services. According to our result, PS can be considered as a mediation variable for bridging between two different concepts: trust that explains social aspects of customers and companies, and TAM that explains customers' reuse intention.

• Childhood Kidney Diseases
• /
• v.12 no.2
• /
• pp.150-156
• /
• 2008

Purpose : Many results have reported a correlation between the spot urine protein/creatinine ratio(P/C ratio) and 24-hour urinary protein(24UP) amount. This study was designed to evaluated correlation between 24UP amounts and P/C ratio in children and to find the factors that affect this correlation. Methods : 210 patients who visited the Department of Pediatrics in Busan Paik Hospital from september 2003 to december 2007 were included in this study. All the patients were divided into I, II, III/A, B, C group[I:24UP(mg/$m^2$/day)]<100, II: 100$\leq$24UP<1,000, III: 24UP$\geq$1,000, A: Cr excretion(mg/kg)<15, B: 15$\leq$Cr excretion<25, C: Cr excretion$\geq$25)]. Pearson correlation analysis was performed between 24UP and P/C ratio to evaluate the relationship. We defined fractional difference between 24UP and P/C ratio, and then performed multiple regression analysis. Results : There was a strong positive linear correlation between 24UP and P/C ratio in all patients, and the correlation was also good in each group. The factors affecting accurate quantitation of proteinuria using spot urine P/C ratio was creatinine excretion. Conclusion : Spot urine P/C ratio is a useful test to predict proteinuria roughly. Therefore, we expect that urine P/C ratio can be used as parameter instead of 24UP, if we set cutoff value of P/C ratio considered to creatinine excretion according to age and sex in large pediatric population.

• Research in Plant Disease
• /
• v.15 no.2
• /
• pp.63-67
• /
• 2009

Rice stripe virus (RSV) is one of Tenuivirus Group, which is carried by small brown planthopper. There is an outbreak of RSV in South Korea at 20Ot, and 2007. The infection caused by RSV had been investigated on weeds around the rice cultivated areas 13 region and 26 site including Jeonbuk Buan and Chungnam Seocheon. There have a doubt as to alternate host of RSV is total 15 Family and 50 Species including Gramineae 24 species of Duksaepul (Alopecurus aequalis), H. sativum var. vulgare etc.. There is identified the infected RSV in Festuca myuros, Alopecurus aequalis, Hordeum sativum var. vulgare, Trisetum bifidum, Echinochloa crus-galli var. crus-galli, Digitaria ciliaris among this species. Deulmuksae is the overwintering exotic weed which sprout in Autumn and wither in Spring and commonly growed as green manure crop or cover crop. In order to identify the infection rate furthermore, 111 samples which were collected at Buan Gyehwa-myeon region, and 50 samples from Seocheon Maseo-myeon in June, 2008, were ELISA tested. The results are 32 positives from Buan, 28.8% infection rate, 8 positives from Seocheon 16.0% infection rate. RSV infection of Deulmuksae is not reported currently, and follow report first describes the Deulmuksae as an alternate host of RSV.

• Korean Journal of Microbiology
• /
• v.37 no.1
• /
• pp.92-99
• /
• 2001

High-cell-density cultivation of Ralstonia eutopha KHB 8862 by fed-batch fermentation in a 200 l pilot plant was carried out for the mass production of poly(3-hydroxybutyrate) (PHB). After 80 h of cultivation, the dry cell weight (DCW), PHB concentration, and PHB yield from fructose syrup reached 168 g/l, 74%DCW, and 0.27 (w/w), respectively, resulting in a productivity of 1.6 g of PHB/L/h. Based on these results, the PHB production cost from bacterial fermentation was analyzed and economic evaluation was performed. In the case of new investment being implemented or not, the production cost of PHB was US$ 3.15/kg and US$ 2.41/kg, respectively. PHB productivity and PHB yield on a carbon substrate were both important factors to be optimized. The increase of PHB yield on a carbon sources significantly decreased the PHB production cost but the increase in productivity had a relatively slight effect on the decrease in PHB production cost because the cost of carbon sources (37%) for PHB was larger in proportion to total cost than the depreciation cost (17%). These results suggest that the increased PHB yield from carbon sources and the development of new cheaper substrates would be more effective in decreasing PHB production cost than the increase in productivity. It was demonstrated that PHB is not in competition with consumable plastics such as PET in present market. Therefore, it is essential to lower production cost to be used as a bulk product and desirable to develop new application fields for PHB such as biomedical and cosmeceuticals.

• Development and Reproduction
• /
• v.6 no.1
• /
• pp.17-23
• /
• 2002

In oocyte retrieval, a vein anesthetic drug is commonly used for induction and maintenance of general anesthesia. Propofol and Thiopental sodium are frequently used for ultrasound-guided transvaginal oocyte retrieval. The present study aimed to assess the effects of Propofol and Thiopental on in vitro fertilization(IVF). Immature porcine oocytes were exposed to various concentrations ot Propofo1 and Thiopental sodium. The rates of oocyte maturation, fertilization and development were observed. The parthenogenetic effects of the anesthetics were also evaluated. The rate of oocyte maturation after exposure to high concentrations of the anesthetics for long time was significantly higher than that of the control. But the rate of fertilization after long-time exposure to the high concentration of the anesthetic drugs was significantly lower than that of the control. The results support that Propofo1 serves like other anesthetics described, as a parthenogenetic activator. Oocytes exposed to Thiopental sodium showed decreased rates of maturation and fertilization. These results suggest that usage of optimum concentration of anesthetic drug is important in increasing the rates of oocyte maturation, fertilization and development in IVF.

• Korean Journal of Acupuncture
• /
• v.18 no.1
• /
• pp.157-164
• /
• 2001

Radix Asteris has been used in Korea for many centuries as a treatment for respiratory disease. The effect of Radix Asteris on tracheal smooth muscle is not known. The purpose of the present study is to determine the effect of Radix Asteris on histamine induced tracheal smooth muscle contraction in rats and guinea pigs. Guinea pig(500g, male) and Sprague Dawley rats (250g, male) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from each rat and guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine (His) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine $(10^{-7}{\sim}10^{-4}M)$. Contractions evoked by His ($ED_{50}$) were inhibited significantly by Radix Asteris. In guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 120.5% (p<0.01) after $100{\mu}l/ml$ Radix Asteris. In rat tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 135.4% (p<0.01) after $100{\mu}l/ml$ Radix Asteris. Propranolol $(10^{-7}M)$ slightly but significantly attenuated the inhibitory effects of Radix Asteris. Following treatment with propranolol, the mean percent inhibition caused by $100{\mu}l/ml$ Radix Asteris fell to 44.6% in guinea pig induced by histamine contraction and by $100{\mu}l/ml$ Radix Asteris fell to 18.7% (p<0.05) in rat induced by histamine contraction. Indomethacin and methylene blue$(10^{-7}M)$ did not significantly alter the inhibitory effect of Radix Asteris. These results indicate that Radix Asteris can relax histamine induced contraction of guinea pig and rat tracheal smooth muscle, and that this inhibition involves sympathetic effects.

• Korean Journal of Agricultural Science
• /
• v.1 no.1
• /
• pp.27-33
• /
• 1974

This experiment was carried out to determine the adequate amount of nitrogen for densely and lately seeded soybean, and the results obtained are as follows; 1) Various fertilization amounts of nitrogen did not effect the date of emergency, but the flowering and the maturing dates were delayed at the plots fertilized the nitrogen heavily. 2) In accordance with an increasing amount of nitrogen fertilization, the length of the stem and the internode was s gnificantly enlongated but the stem diameter was thinned down, and the latter was suggested to be the cause of lodging. 3) The 1,000 grain weight and the number of pods per hill were decreased according to the increasing the amount of nitrogen fertilization. 4) A highly significant difference in grain yield was recognized between varieties but among treatments. However, in case ot the extremly late cultivation, the grain yield of the early maturing variety (Choongbukbaek) was increased at the plot of 6 kg nitrogen.

• Korean Journal of Veterinary Research
• /
• v.39 no.6
• /
• pp.1119-1125
• /
• 1999

Since Robert Koch found tubercle bacilli in 1882, the studies on tubercle bacilli of human and animal had been carried out. Being old tuberculin(OT) introduced in 1890, the specificity of the diagnosis of tuberculosis has been improved by continual uses of heat concentrated synthetic medium(HCSM) and purified protein derivatives(PPD) tuberculin. Now, two types of tuberculin test are used worldwidly ; the single intradermal test(SIT) using bovine tuberculin and the single intradermal comparative tuberculin test(SICTT) using avian and bovine tuberculins. In the SICTT, each countries have used with different combination of both avian and bovine tuberculins' titers. However, this kinds of studies have not reported in Korea. Therefore, the studies on the combination of their tuberculins' titers were performed through intradermal test of guinea pigs sensitized with either Mycobacterium bovis or M avium and were examined in 10 cattles of SIT positive reactors. Also, IFN-${\gamma}$ assay, the latest diagnostic method of bovine tuberculosis, was experimentally applied to SIT positive reactors. For determining the optimal titers, sensitized guinea pigs with M bovis and M avium were intradermally injected avian and bovine tuberculin. In guinea pigs sensitized with M bovis, bovine tuberculin 50 T.U. showed significant difference from all tested concentrations of avian tuberculin(p < 0.05). In guinea pigs sensitized with M avium, there is significantly different between bovine tuberculin and avian tuberculin by 25 T.U.(p < 0.01). Therefore, optimal titers of bovine and avian PPD tuberculins' titers for the SICTT in Korea were 5,000 and 2,500 tuberculin units, respectively, and the swelling diffences between bovine and avian site in SIT positive reactors were above 3mm. Also, in IFN-${\gamma}$ assay, the 9 SIT positive reactors were showed all the positive reactions.

• Food Science of Animal Resources
• /
• v.26 no.3
• /
• pp.349-355
• /
• 2006

A total of 120 pigs (Berkshire) were used to investigate the effect of dietary supplementation with artificial culture medium ot wild ginseng (CMWG) on the fatty acid composition, amino acid composition and sensory characteristics or pork About $60{\pm}3kg$ pigs were randomly assigned to one of four experimental diet groups[(both sexes)${\times}$(C: commercial diet feed; T: commercial diet+1 L CMWG per day for 70 days)]. Pigs were slaughtered at approximately 110 kg live weight, and fatty acid composition, amino acid composition and sensory characteristics were measured in pork loin. The monounsaturated and saturated fatty acid contents was greater in barrow fed a diet containing CMWG than those of the gilt pork and control groups, however the polyunsaturated fatty acid composition decreased. The EAA (essential amino acid) content was lower in pigs fed diets containing CMWG than that of the control groups, whereas the SAA (amino acid with sulfide) and FRAA (fragrant amino acid) contents were higher. The EAA and FAA (amino acid in relation to flavor) contents were lower for harrow than for gilt, however the SAAA (amino acid in relation to saccarinity), SAA and FRAA the contents were higher. Regarding the sensory evaluation of fresh meat, the color of gilt pork increased with diets containing CMWG relative to the control group. Drip loss and the marbling score for pigs fed with diets containing CMWG were higher in barrow than in gilt. The flavor and overall acceptability of cooked meat from the control group was higher for barrow than for silt.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2016.11a
• /
• pp.59-75
• /
• 2016

Reduced or black $TiO_{2-x}$ materials with oxygen-deficiency have been achieved by creating oxygen vacancies and/or defects at the surface using different methods. Fascinatingly, they exhibited an extended absorption in VIS and IR instead of only UV light with bandgap decrease from 3.2 (anatase) to ~1 eV. However, despite the dramatic enhancement of optical absorption in black $TiO_{2-x}$ materials, they have failed to show expected visible light-assisted water splitting efficiency. This was ascribed to the high concentration of the surface defects and/or oxygen vacancies, considered as an electron donor to enhance donor density and improve the charge transportation in black $TiO_2$ can also act as charge recombination centers, which eventually decrease photocatalytic activity. Therefore, a black ot reducd $TiO_2$ material with optimized properties would be highly desired for visible light photocatalysis. In this report, a new controlled magnesiothermic reduction has been developed to synthesize reduced black $TiO_{2-x}$ in the presence $H_2/Ar$ for photocatalytic $H_2$ production from methanol-water system. The material possesses an optimum band gap and band position, oxygen vacancies, and surface defects and shows significantly improved optical absorption in the visible and infrared region. The synergistic effects enable the reduced $TiO_{2-x}$ material to show an excellent hydrogen production ability along with long-term stability under the full solar wavelength range of light and visible light, respectively, in the methanol-water system in the presence of Pt as a co-catalyst. These values are superior to those of previously reported black $TiO_2$ materials. On the basis of all the results, it can be realized that the outstanding activity and stability of the reduced of $TiO_{2-x}$ NPs suggest that a balanced combination of different factors like $Ti^{3+}$, surface defects, oxygen vacancy, and recombination center is achieved along with optimized bandgap and band position during the preparation employing magnesiothermic reduction in the presence of $H_2$. The controlled magnesiothermic reduction in the presence of $H_2$ is one of the best alternative ways to produce active and stable $TiO_2-based$ photocatalyst for $H_2$ production.