• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.25 no.2
• /
• pp.56-61
• /
• 2015

The effects of the growth temperature on the properties of a-plane GaN epi-layer on r-plane sapphire by HVPE were studied, when the constant V/III ratio and the flow rate of HCl for the Ga source channel was fixed at 10 and 700 sccm, respectively. Additionally the effects of V/III ratios for source gasses were studied when growth temperature and the flow rate of HCl for the Ga source channel was fixed at $1000^{\circ}C$ and 700 sccm, respectively. As the growth temperature was increased, the values of Full Width Half Maximum (FWHM) for Rocking curve (RC) of a-plane GaN (11-20) epi-layer were decreased and thickness of a-plane GaN epi-layer were increased. As V/III ratios were increased at $1000^{\circ}C$, the values of FWHM for RC of a-plane GaN (11-20) were declined and thickness of a-plane GaN epi-layer were increased. The a-plane GaN (11-20) epi-layer grown at $1000^{\circ}C$ and V/III ratio = 10 showed the lowest value FWHM for RC of a-plane GaN (11-20) for 734 arcsec and the smallest dependence of Azimuth angle for FWHM of (11-20) RCs.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.1 s.343
• /
• pp.103-110
• /
• 2006

Internet engineering task force (IETF) has proposed hierarchical mobile IPv6 (HMIPv6) in order to reduce a frequent location registration of a mobile node in mobile IPv6 (MIPv6). All traffics toward a mobile node must be transmitted through a MAP in HMIPv6. This brings unnecessary packet latency because of the increased processing cost of packet at the MAP. At this point the processing cost of packet at the MAP is influenced by the packet arrival rate for a mobile node and the number of mobile nodes in MAP domain. In this paper, we propose that MIPv6 and HMIPv6 are adaptively selected to minimize signaling coast of network as complementing weak point of MIPv6 and HMIPv6. After suppose that the packet arrival rate for a mobile node is fixed ,with this in mind, we find the optimal number of mobile nodes compared the total cost of HMIPv6 with the total cost of MIPv6. And if Mobile Nodes that the MAP is able to manage is full in MAP domain, a mobile node entering MAP domain is provided connection by MIPv6 instead of HMIPv6. In the conclusion, the proposed method of this paper shows that the weak points of MIPv6 and HMIPv6 are removed by adaptive selecting each other.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.39 no.4
• /
• pp.366-372
• /
• 2012

The aim of this study was to compare two commercial root canal medicaments, ProRoot MTA (Dentsply Tulsa, USA) and OrthoMTA (Bio MTA, Korea), by assessing the antimicrobial effects on three selected species commonly found in root canals of infected teeth, namely Enterococcus faecalis, Fusobacterium nucleatum and Staphylococcus epidermidis. Colonies of these bacteria were treated with varied concentrations of ProRoot MTA or OrthoMTA over different lengths of time. The results are as follows : 50, 25 and 12.5 mg/mL of ProRoot MTA or OrthoMTA did not completely inhibit the growth of E. faecalis, but a decreased growth rate was evident in comparison to the control (p < 0.05). 50 mg/mL of both materials successfully eliminated F. nucleatum during the first 24 hours. Regrowth of microbes after 24 hours, however, indicated a diminished effect of ProRoot MTA whereas OrthoMTA showed its continuously sustained antimicrobial actions (p < 0.05). 50 mg/mL of ProRoot MTA and 50, 25 mg/mL of OrthoMTA exerted their full antibacterial actions against S. epidermidis during the first 24 hours. Although the regrowth of colony was observed after 24 hours, the rate of growth was significantly decreased, approximating a complete inhibition (p < 0.05). The present study revealed that OrthoMTA, recently developed in Korea, had antimicrobial activity higher than ProRoot MTA.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.12
• /
• pp.1843-1848
• /
• 2007

Thirty-six 1.5 year-old Inner Mongolian White Cashmere wether goats (body weight $28.14{\pm}1.33$ kg) were used to determine the effects of dietary copper (Cu) concentration on ruminal fermentation, nutrient digestibility and cashmere fibre characteristics. Wethers were fed a basal diet (containing 7.46 mg Cu/kg DM) that was supplemented with either 0 (control), 10, 20 or 30 mg Cu/kg DM. To ensure full consumption, animals were fed restrictedly with 0.75 kg feed (DM) in two equal allotments per day. The results indicated that: (1) supplemental 10 mg Cu/kg DM in the basal diet significantly (p<0.05) decreased ruminal fluid pH value and total VFA concentrations were significantly (p<0.05) increased on all Cu treatment groups. (2) Cu supplementation had no influence on DM intake and digestibility of DM, CP and ADF (p>0.05); however, NDF digestibility of groups supplemented with 10 and 20 mg Cu/kg DM were significantly higher than that of the control group (p<0.05). Apparent absorption and retention of copper were decreased with increasing level of supplementation. (3) 20 mg Cu/kg DM treatment significantly (p<0.05) improved cashmere growth rate, but cashmere diameter was not affected by Cu supplementation (p>0.05). In conclusion, supplementation of cashmere goats with Cu at the rate of 10 to 20 mg/kg DM in the basal diet resulted in some changed rumen fermentation and was beneficial for NDF digestibility, while supplementation of 20 mg Cu/kg DM improved cashmere growth. Collectively, the optimal supplemental Cu level for cashmere goats during the fibre growing period was 20 mg/kg DM (a total dietary Cu level of 27.46 mg/kg DM).

• Journal of Distribution Science
• /
• v.14 no.7
• /
• pp.71-81
• /
• 2016

Purpose - Because creativity, which is an intangible resource embedded within the company, can offer a competitive advantage, most companies have an interest in promoting creativity among their employees and division(e.g., marketing organization). Creativity renders a sustainable competitive advantage to a firm because it is a strategic resource that is valuable, flexible, rare, and imperfectly imitable or substitutable. Although most companies broadly recognize the importance of creativity, the methods for developing creativity remain elusive. Therefore, the present study investigates how to structure incentives to motivate employees to be more creative and how to develop tools to facilitate creativity. In detail, the present study aimed to examine the relationship between the regulatory focus of marketing organizations(e.g., promotion focus vs prevention focus) and creativity of marketing organizations. In addition, the present study set out to examine the moderating role of interaction of financial reward and creative training in addition to investigating the direct relationship between creativity and regulatory focus in New Product Development(NPD) context. Research design, data, and methodology - The data used to test the hypotheses are drawn from a survey of full time NPD project members(including project manager, designer, engineer, and marketer). The present study utilized data obtained mainly from a database compiled by the Korea Investors Service-Financial Analysis System which provides comprehensive corporate and financial information on firms listed on the Korea Stock Exchange. A study population comprising 1,000 South Korean firms was obtained from this database. We selected 864 firms from the database, and the firms have experiences of new product development project. We collected a total of 162 responses, for a 18.8% response rate. After we excluded 14 questionnaire because of incomplete responses, a total of 148 questionnaire remained(final response rate: 17.1%). Working with a sample of 148 responses in South Korea, hierarchical moderated regression is employed to test research hypotheses(

The relationship between promotion focus and creativity of marketing organization,

The relationship between prevention focus and creativity of marketing organization,

The moderating effect of joint influences(interaction between financial rewards and creativity training) on the relationship between promotion focus creativity of marketing organization,

The moderating effect of joint influences(interaction between financial rewards and creativity training) on the relationship between prevention focus creativity of marketing organization). SPSS 18.0 and AMOS software were used in the data analysis. Results - The empirical study confirmed that promotion focus of marketing organization is positively related to creativity of marketing organization. Also, prevention focus of marketing organization is positively affected to creativity of marketing organization. In addition, the interaction between financial rewards and creativity training moderated the relationship between regularity focus(e.g.), promotion focus vs prevention focus) and creativity of marketing organization. These results suggest that managers can improve the performances of their creative efforts by providing the use of financial rewards and creativity training in combination. Conclusion - Based on results of this study that examine the effects of regulatory focused creative efforts on creativity of marketing organization, promotion focus is helpful with marketing organizations to enhance their service innovation and performance. Prevention focused organization should allow monetary rewards and creativity training to increase their creativity for innovation of new products.

• Journal of Environmental Impact Assessment
• /
• v.14 no.5
• /
• pp.347-353
• /
• 2005

The risk assessment is the qualitative or quantitative evaluation of the risk posed to human health and the environment by the actual or potential presence or release of hazardous substances, pollutants or contaminants. The environmental impact assessment (EIA) is assessed by the environmental criteria, and risk assessment is assessed by the risk rate. Risk rate based on dose-response values may not be easy to apply on regulatory basis like EIA for uncertainty. Internationally there is an example of OECD program. Risk assessment of High Production Volume (HPV) Chemicals has started since the OECD Program with the 1990 Council Act on the Co-operative Investigation and Risk Reduction of Existing Chemicals. These HPV chemicals include all chemicals produced or imported at levels greater than 1,000 tonnes per year in at least one Member country or in the European Union region. The SIDS called the Screening Information Data Set is regarded as the minimum information needed to assess an HPV chemical to determine whether any further work should be carried out or not. All the data elements of SIDS including assessment for environment and health are prepared as three formats of the full SIDS Dossier, the SIDS Initial Assessment Report (SIAR), and the SIDS Initial Assessment Profile (SIAP) of an HPV chemical. In 1998 the global chemical industry through the International Council of Chemical Associations (ICCA) has joined to work with OECD. The OECD has assessed approximately 1,000 chemicals from 1991 through 2004 with ICCA. Till the February of 2005, 592 chemicals of those chemicals completed SIDS reports. Member countries have been targeted the goal of 1,000 new chemicals from 2005 to 2010 and Korea shared 36 chemicals from the 1,000 new chemicals. Currently Korea has completed SIDS reports of 7 chemicals among sponsored 24 chemicals. In conclusion SIDS project will be linked to national program for outputs application with more reliable production. Both the OECD and industry will carry out their commitment to complete assessments for more and the remaining chemicals assessment. The major outputs will contribute to cope with international chemical management.

• Journal of Plant Biotechnology
• /
• v.42 no.1
• /
• pp.49-54
• /
• 2015

Based on the results in this study, here we propose a systematic micropropagation process for 'Gisela 5' that is one of the important dwarfing cherry rootstocks. When the apical tips detached from newly developed shoot in spring season were cultured on the half strength MS media with 0.5 mg/L IBA and 0.5 ~ 1.0 mg/L BA, the cultures scored the highest acquisition rate at 90% for normal shoot with vigorous growth and without hyperhydricity. As next step, the young shoots maintained in vitro well multiplied on the full strength MS medium supplemented with 0.5 mg/L IBA and 0.5 mg/L BA, in which multiplication rate was approximately nine-fold. Given the half strength MS medium containing 2.0 mg/L IBA, each transplanted shoot further developed robust roots. Finally, the plantlets were easily acclimatized in the compost consisted of vermiculite, perlite, and peatmoss in the proportion of 1:1:1. We expect that the results are useful for cherry cultivation and its rootstock production.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.33 no.3
• /
• pp.173-182
• /
• 1997

This study is a basic research in purse seine fishery : on the behaviour of fish schools of tilapia Tilapia mossambica in the process of catch of the purse seine fishing method. The experiment was carried out for the mackerel purse seine which using of power block by fishing fleet system in the near sea of Cheju Island and as a forecast in the near future on the purse seine fishing, using of triplex net winch by one boat system in the near sea of Norway. These model purse seines were made of the scale of 1/180 of its full scale. The model purse seine test on the escaping behaviour of fish school by gap, area reducing of gap and tension of purse line was carried out in the stagnant water of experimental water tank. Designing and testing for the model purse seines were based on the Tauti's law. The results obtained were as follows : 1. When the time for the completing of pursing was 20 minutes, average swimming speed of fish school through a gap was 9.71cm/sec for powerblock seine and 9.97cm/sec for triplex seine. 2. In the case of pursing time in actual value was 20minutes, at 50 percent of the pursing, swimming behaviour of fish school in purse seine was 10% to I section, 80% to II section, 10% to III sectional direction for powerblock seine and a similar tendency for triplex seine. 3. In the case of pursing time in actual value was 20 minutes, at the time of 10 minutes have proceeded since then, area reducing rate of gap of the seine in projected front view was 63.5% for powerblock seine and 67.5% for triplex seine. 4. In the case of pursing time in actual value was 20 minutes, escaping rate of fish school by gap in projected front view was 70% for powerblock seine and 30% for triplex seine. Maximum tension of purse line was about 8.1 tons for powerblock seine and about 8.3 tons for triplex seine.

• Fire Science and Engineering
• /
• v.26 no.3
• /
• pp.21-28
• /
• 2012

The objective of this study is to evaluate the prediction accuracy of FDS(Fire Dynamic Simulator) for the thermal and chemical characteristics of under-ventilated fire with unsteady fire growth in a semi-closed compartment. To this end, a standard doorway width of the full-scale ISO 9705 room was modified to 0.1 m and the flow rate of heptane fuel was increased linearly with time (until maximum 2.0 MW based on ideal heat release rate) using a spray nozzle located at the center of enclosure. To verify the capability of FDS, the predicted results were compared with a previous experimental data under the identical fire conditions. It was observed that with an appropriate grid system, the numerically predicted temperature and heat flux inside the compartment showed reasonable agreement with the experimental data. On the other hand, there were considerable limitations to predict accurately the unsteady behaviors of CO and $CO_2$ concentration under the condition of continuous fire growth. These results leaded to a discrepancy between the present evaluation of FDS and the previous evaluation conducted for steady-state under-ventilated fires. It was important to note that the prediction of transient CO production characteristics using FDS was approached carefully for the under-ventilated fire in a semi-closed compartment.

• Journal of Pharmaceutical Investigation
• /
• v.26 no.3
• /
• pp.175-185
• /
• 1996

To inhibit the enzymatic degradation of leucine enkephalin (Leu-Enk) and its synthetic analog. $[D-ala^2]$-leucine enkephalinamide (YAGFL), in the nasal, rectal and vaginal mucosal and serosal extracts of rabbits, effects of enzyme inhibitors such as amastatin (AM), puromycin (PM), thiorphan (TP), thimerosal (TM), EDTA, N-carboxymethyl-Phe-Leu (CPL), phenylethyl alcohol (PEA), phenylmercuric acetate (PMA), benzalkonium chloride (BC) and modified cyclodextrins, alone or in combination, were observed by assaying the pentapeptides staying intact during incubation. Mucosa extracts were prepared by exposing freshly-excised mucosal specimens mounted on Valia-Chien cells to isotonic phosphate buffer while stirring. The degradation of Leu-Enk and YAGFL followed the apparent first-order kinetics. The half-lives (mean) in the nasal, rectal and vaginal mucosal extracts were found to be 1.07, 0.33 and 1.14 hr for Leu-Enk, and 16.9, 6.2 and 6.8 hr for YAGFL, respectively. AM or PM, which is an aminopeptidase inhibitor, did not show a sufficient inhibition of Leu-Enk $(50\;{\mu}g/ml)$ degradation in all kinds of extracts. $Dimethyl-{\beta}-cyclodextrin\;(DM-{\beta}-CyD)$ decreased the degradation rate constants of Leu-Enk about 2 or 3 times, comparing with no additive. However, the use of mixed inhibitors of AM $(50\;{\mu}M)$/TM (0.25 mM)/EDTA (5 mM) resulted in a full stabilization of Leu-Enk by decreasing the degradation rate constants 67.3, 161.3 and 113.8 times far the nasal, rectal and vaginal mucosal extracts, respectively, comparing with no inhibitor. With mixed inhibitors, Leu-Enk remained intact more than 90% after 6 hr-incubation. In the stabilization of YAGFL, hM, TP or CPL alone showed little efffct, and some additives demonstrated a considerable inhibition of YAGFL degradation in the rank order of TM > BC > EDTA. However, the addition of mixed inhibitors such as TM (0.5 mM) and EDTA (5 mM) into the extracts protected YAGFL from the degradation by more than 85% even after 24 hr-incubation, suggesting almost complete inhibition of YAGFL degradation in the extract. On the other hand, $DM-{\beta}-CyD\;or\;hydroxypropyl-{\beta}-cyclodextrin$ (10%) were also found to retard enzymatic degradation rates of YAGFL markedly, and resulted in staying intact more than 80% of YAGFL in the nasal and vaginal mucosal extracts, and more than 60% in the rectal mucosal extract after 16 hr-incubation.