• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.445-456
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• 2009

Statement of problem: Many studies have been conducted to improve the primary stability of implants by providing bioactive surfaces via surface treatments. Increase of surface roughness may increase osteoblast activity and promote stronger bonding between bone and implant surface and it has been reported that bioactive surface or titanium can be obtained through alkali and heat treatment. Purpose: The purpose of this study was to evaluate the stability of alkali and heat treated implants via histomorphometric analysis. Material and methods: Specimens were divided into three groups; group 1 was the control group with machined surface, the other groups were treated for 24 hours in 5 M NaOH solution and heat treated for 1 hour at $600^{\circ}C$ in the atmosphere (group 2) and vacuum (group 3) conditions respectively. Surface characteristics were analyzed and fixtures were implanted into rabbits. The specimens were histologically and histomorphometrically compared according to healing periods and change in bone composition were analyzed with EPMA (Electron Probe Micro Analyzer). Results: 1. Groups treated with alkali and heat showed increase of oxidization layer and Na ions. Groups 2 which was heat treated in atmosphere showed significant increase of surface roughness (P<.05). 2. Histomorphometric analysis showed significant increase in BIC (bone to implant contact) according to increase in healing period and there was significant increases in groups 2 and 3 (P<.05). 3. BA(bone area) ratio showed similar results as contact ratio, but according to statistical analysis there was significant increase according to increase in healing period in group 2 only (P<.05). 4. EPMA analysis revealed no difference in gradation of bone composition of K, P, Ca, Ti in surrounding bone of implants according to healing periods but groups 2 and 3 showed increase of Ca and P in the initial stages. Conclusion: From the results above, it can be considered that alkali and heat treated implants in the atmosphere have advantages in osseointegration in early stages and may decrease the time interval between implantation and functional adaptation.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.327-336
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• 2016

The Bagan, the central part of Myanmar, is dry zone where the mean annual precipitation is less than 600 mm for the last ten years. Forest in this region has been degraded due to biotic and abiotic disturbances. While there have been various efforts to rehabilitate the degraded area, the information on growth and physiological characteristics of planting species and the impacts of planting trees in the region still lacks. Therefore, this study was conducted to determine the growth and physiological water use efficiency characteristics of five species (Azadirachta indica A. Juss., Acacia catechu Willd., Eucalyptus camaldulensis Dehn., Acacia leucophloea (Roxb.) Willd. and Albizia lebbek (L.) Willd.) which are utilized as rehabilitation species in the dry zone and to identify the impacts of tree planting on microclimate change in dry zone. The growth and the foliar carbon isotope composition of seedlings and the above mentioned five species planted in 2005 were measured. And from February 2015 to January 2016, microclimatic factors air temperature and relative humidity at 60 cm and 2 m above soil, soil temperature, soil water contents and precipitation were measured at every 30-minute interval from the two weather stations installed in the plantation located in Ngalinpoke Mt. Range. One was established in the center of A. indica plantation, and the other was in the barren land fully exposed to the sunlight. Among the five species, A. indica and A. lebbek which showed higher water use efficiency could be recommended as rehabilitation species in dry zone. Planting trees in the dry area was shown to affect the change of microclimate with shading effects, declining temperature of the land surface and aridity of the air, and to contribute to conserving more water in soil by preventing direct evaporation and containing more water with fine roots of trees.

• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.169-179
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• 2007

This study was to compare the microshear bond strength $({\mu}SBS)$ of light- and chemically cured composites to enamel coupled with four 2-step self-etch adhesives and also to evaluate the incompatibility between 2-step self-etch adhesives and chemically cured composite resin. Crown segments of extracted human molars were cut mesiodistally, and a 1 mm thickness of specimen was made. They were assigned to four groups by adhesives used: SE group (Clearfil SE Bond) AdheSE group (AdheSE), Tyrian group (Tyrian SPE/One-Step Plus), and Contax group (Contax) Each adhesive was applied to a cut enamel surface as per the manufacturer's instruction. Light-cured (Filtek Z250) or chemically cured composite (Luxacore Smartmix Dual) was bonded to the enamel of each specimen using a Tygon tube. After storage in distilled water for 24 hours, the bonded specimens were subjected to ${\mu}SBS$ testing with a crosshead speed of 1 mm/minute. The mean ${\mu}SBS$ (n=20 for each group) was statistically compared using two-way ANOVA, Tukey HSD, and t test at 95% level. Also the interface of enamel and composite was evaluated under FE-SEM. The results of this study were as follows ; 1. The ${\mu}SBS$ of the SE Bond group to the enamel was significantly higher than that of the AdheSE group, the Tyrian group, and the Contax group in both the light-cured and the chemically cured composite resin (p < 0.05). 2. There was not a significant difference among the hdheSE group, the Tyrian group, and the Contax group in both the light-cured and the chemically cured composite resin. 3. The ${\mu}SBS$ of the light-cured composite resin was significantly higher than that of the chemically cured composite resin when same adhesive was applied to the enamel (p < 0.05). 4. The interface of enamel and all 2-step self-etch adhesives showed close adaptation, and so the incompatibility of the chemically cured composite resin did not show.

• Journal of Distribution Science
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• v.9 no.3
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• pp.83-94
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• 2011

Most domestic companies, with the exclusion of major firms, are reluctant to implement a supply chain management (SCM) network into their operations. Most small- and medium-sized enterprises are not even aware of SCM. Due to the inherent total-systems efficiency of SCM, it coordinates domestic manufacturers, subcontractors, distributors, and physical distributors and cuts down on cost of inventory control, as well as demand management. Furthermore, a lack of SCM causes a decrease in competitiveness for domestic companies. The reason lies in the fundamentality of SCM, which is the characteristic of information sharing, process innovation throughout SCM, and the vast range of problems the SCM management tool is able to address. This study suggests the contemplation and reformation of the current SCM situation by analyzing the SCM strategic plan, discourses and logical discussions on the topic, and a successful case for adapting SCM; hence, the study plans to productively "process" SCM. First, it is necessary to contemplate the theoretical background of SCM before discussing how to successfully process SCM. I will describe the concept and background of SCM in Chapter 2, with a definition of SCM, types of SCM promotional activities, fields of SCM, necessity of applying SCM, and the effects of SCM. All of the defects in currently processing SCM will be introduced in Chapter 3. Discussion items include the following: the Bullwhip Effect; the breakdown in supply chain and sales networks due to e-business; the issue that even though the key to a successful SCM is cooperation between the production and distribution company, during the process of SCM, the companies, many times, put their profits first, resulting in a possible defect in demands estimation. Furthermore, the problems of processing SCM in a domestic distribution-production company concern Information Technology; for example, the new system introduced to the company is not compatible with the pre-existing document architecture. Second, for effective management, distribution and production companies should cooperate and enhance their partnership in the aspect of the corporation; however, in reality, this seldom occurs. Third, in the aspect of the work process, introducing SCM could provoke corporations during the integration of the distribution-production process. Fourth, to increase the achievement of the SCM strategy process, they need to set up a cross-functional team; however, many times, business partners lack the cooperation and business-information sharing tools necessary to effect the transition to SCM. Chapter 4 will address an SCM strategic plan and a case study of LG Electronics. The purpose of the strategic plan, strategic plans for types of business, adopting SCM in a distribution company, and the global supply chain process of LG Electronics will be introduced. The conclusion of the study is located in Chapter 5, which addresses the issue of the fierce competition that companies currently face in the global market environment and their increased investment in SCM, in order to better cope with short product life cycle and high customer expectations. The SCM management system has evolved through the adaptation of improved information, communication, and transportation technologies; now, it demands the utilization of various strategic resources. The introduction of SCM provides benefits to the management of a network of interconnected businesses by securing customer loyalty with cost and time savings, derived through the consolidation of many distribution systems; additionally, SCM helps enterprises form a wide range of marketing strategies. Thus, we could conclude that not only the distributors but all types of businesses should adopt the systems approach to supply chain strategies. SCM deals with the basic stream of distribution and increases the value of a company by replacing physical distribution with information. By the company obtaining and sharing ready information, it is able to create customer satisfaction at the end point of delivery to the consumer.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.562-581
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• 2018

This study was designed to predict the changes in species richness of plants under the climate change in South Korea. The target species were selected based on the Plants Adaptable to Climate Change in the Korean Peninsula. Altogether, 89 species including 23 native plants, 30 northern plants, and 36 southern plants. We used the Species Distribution Model to predict the potential habitat of individual species under the climate change. We applied ten single-model algorithms and the pre-evaluation weighted ensemble method. And then, species richness was derived from the results of individual species. Two representative concentration pathways (RCP 4.5 and RCP 8.5) were used to simulate the species richness of plants in 2050 and 2070. The current species richness was predicted to be high in the national parks located in the Baekdudaegan mountain range in Gangwon Province and islands of the South Sea. The future species richness was predicted to be lower in the national park and the Baekdudaegan mountain range in Gangwon Province and to be higher for southern coastal regions. The average value of the current species richness showed that the national park area was higher than the whole area of South Korea. However, predicted species richness were not the difference between the national park area and the whole area of South Korea. The difference between current and future species richness of plants could be the disappearance of a large number of native and northern plants from South Korea. The additional reason could be the expansion of potential habitat of southern plants under climate change. However, if species dispersal to a suitable habitat was not achieved, the species richness will be reduced drastically. The results were different depending on whether species were dispersed or not. This study will be useful for the conservation planning, establishment of the protected area, restoration of biological species and strategies for adaptation of climate change.

• Korean Journal of Plant Taxonomy
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• v.48 no.4
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• pp.249-259
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• 2018

$Iso{\ddot{e}}tes$ L. ($Iso{\ddot{e}}taceae$) is a cosmopolitan genus of heterosporous lycopods containing ca. 200 species being found in lakes, streams, and wetlands of terrestrial habitats. Despite its ancient origin, worldwide distribution, and adaptation to diverse environment, species in $Iso{\ddot{e}}tes$ show remarkable morphological simplicity and convergence. Allopolyploidy appears to be a significant speciation process in the genus. These characteristics have made it difficult to assess the phylogenetic relationships and biogeographic history of $Iso{\ddot{e}}tes$ species. In recent years, these difficulties have somewhat been reduced by employing multiple molecular markers. Here, we reconstruct the phylogenetic relationships in East Asian $Iso{\ddot{e}}tes$ species. We also provide their divergence time and biogeographic origin using a fossil calibrated chronogram. East Asian $Iso{\ddot{e}}tes$ species are divided into two clades: I. asiatica and the remaining species. $Iso{\ddot{e}}tes$ asiatica from Hokkaido forms a clade with northeastern Russian and western North American $Iso{\ddot{e}}tes$ species. In clade I, western North America is the source area for the dispersal of $Iso{\ddot{e}}tes$ to Hokkaido and northeastern Russia via the Bering land bridge during the late Miocene. The remaining $Iso{\ddot{e}}tes$ species (I. sinensis, I. yunguiensis, I. hypsophila, I. orientalis, I. japonica, I. coreana, I. taiwanensis, I. jejuensis, I. hallasanensis) from East Asia form a sister group to Papua New Guinean and Australian species. The biogeographic reconstruction suggests an Australian origin for the East Asian species that arose through long-distance dispersal during the late Oligocene.

• Korean Journal of School Psychology
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• v.9 no.3
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• pp.485-503
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• 2012

Academic engagement has been known as a strong predictor of students' cognitive and affective outcomes in an educational context. Despite increasing interest and theoretical usefulness of this construct, a few researchers seem to be interested in the validation of instruments to measure academic engagement for Korean students. Thus, this study would like to introduce one of academic scales widely used, UWES-S(Utrecht Work Engagement Scale-Student) (Schaufeli et al., 2002a: 2002b) and to validate the UWES-S for Korean college students. To validate the Korean version of the UWES-S, 651 college students (285 for Field Trial, 366 for Main Study) were used. The procedure is as follows. First, we used an integrated adaptation procedure to produce a Korean version of the UWES-S. Second, EFA(exploratory factor analyses) was applied to explore the factor structure of the UWES-S on the field trial data. Third, the psychometric properties of the UWES-S items were examined by graded response model(GRM). Also CFA(confirmatory factor analysis) was used to examine its internal construct validity for the data from the main study. Finally, the external validity of the UWES-S was scrutinized with the related variables such as academic motivation and satisfaction. As a result, the Korean version of the UWES-S with 13 items was accepted that the four items were excluded from its original version. Second, the internal validity was supported that the 3 factor CFA model(vigor, dedication, absorption) fit the data well. Third, we supported the partial mediation model that academic engagement played as a mediating variable between academic motivation(internal/external) and academic satisfaction. Finally, the differences between a validation of UWES-S for Korean college and high school students, the necessity of construct equivalence testing, and direction for future research of scale validating were discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.276-284
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• 2023

Nitrogen is a major and essential macronutrient for plant growth and development. However, excessive nitrogen application can lead to ecological pollution or greenhouse gas emissions, consequently resulting in climate change. In this study, we used 153 genetic resources of rice to evaluate the effects of the levels of nitrogen application on grain yield and yield-related traits. Significant differences were noted in the yield and yield-related traits of genetic resources between two nitrogen application levels, namely, 4.5 kg/10a (NN: normal nitrogen condition) and 9.0 kg/10a (LN: low-nitrogen condition). Among the tested traits, days to heading (DTH), clum length (CL), grain yield per plant (GYP), number of panicles per plant (NPP), and number of spikelets per panicle (NSP) decreased by 1.8 to 17.9% when the nitrogen application levels decreased from NN to LN. The 1,000-grain weight (TWG) and percentage of ripened grain (PRG) increased by 2.6 to 11.2% under these conditions. Based on nitrogen application levels, two-way analysis of variance (ANOVA) demonstrated significant differences in GYP, NPP, and PRG but not in NSP and TGW. NPP exhibited negative correlations with NSP (-0.44) and TGW (-0.44), and TGW displayed a negative correlation with PRG (-0.34), whereas, GYP exhibited a positive correlation with PRG (0.37) and NSP (0.38). A similar pattern was recorded under the LN condition. NPP, TGW, and PRG were clustered as PA (principle axis) 1 under the LN condition by factor analysis. NSP and GYP were clustered as PA (principle axis) 2. These results demonstrated NPP and NSP as the primary factors contributing to the decrease in grain yield under LN conditions. In conclusion, we selected eight genetic resources that exhibited higher GYP under both NN and LN conditions with higher NPP or NSP. These genetic resources can be considered valuable breeding materials for the adaptation of plants to nitrogen deficiency.

• Journal of East-West Nursing Research
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• v.7 no.1
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• pp.18-31
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• 2002

This study, as a basic research to manage a Chinese Medicine Health Promotion Center by way of showing an example, is a before and after experiment research for simple group to verify a difference with cholesterol, health status and perception of health in order to confirm a effectiveness of diet and regimen according to the 4th status of physical constitution. Research object was chosen of 42 persons who operate a physical constitutional dietary regimen among them after selecting professors and clinical nurses (55 persons) majoring in the science of nursing who participated in Chinese Medicine-oriented Nurse Training Course from Aug. of 2001 to Feb. of 2002 all over the country. Diagnostic tools for physical constitution was used of the questionary that is currently consisted of physical constitution grouping test in Eastern & Western Diagnose Center of K Medical Center, and rating of health status was used of the tool that standardized CMI(Cornell Medical Index) to be available for Korean, and perception measurement for health status was used of a visual analogue scale for the health status that each one perceive personally, and physiological status was measured of cholesterol in blood. Analysis for the collected data was carried out by percentage, $X^2$ test, paired t-test according to research object by using SPSS, and the results of this study are as follows. 1) There was no difference with cholesterol before or after the experiment for objects. As a result of estimation about difference with health status by areas before or after the experiment, there are more improved result in eyes, ears, digestive organs, bones and sinews organs, frequency of a disorder, habit, adaptation status, angry, healthy status than before the experiment. As a whole, after the experiment the health was more improved than before the experiment. As the result to inspect a difference of health perception between before and after experiment, after the experiment the health perception level was improved than before, however there was no meaningful differences. 2) As the result to inspect a difference of cholesterol between before and after experiment according to object's physical constitution, in the case of So-yang-in(a person with the minimum male: according to the male and female principles(the sun and the moon)) among the 4th status of physical constitution there was only meaningful difference statistically, however, after the experiment their cholesterol's value was increased. As the result to inspect the difference of health status between before and after the experiment according to physical constitution, all of Ta-um-in(a person with maximum the female), So-yang-in(with the minimum male), So-um-in(with the minimum female) had a meaningful difference before and after the experiment, which means that in all case by physical constitutional groups, after the experiment their health status was more improved than before the experiment. As the result to inspect a difference of health perception between before and after according to physical constitutions, in the case of Tae-um-in and So-um-in, average score after the experiment was risen than before the experiment so that it means that the level of health perception was improved, however, there was no meaning statistically. According to the above results, if continuous diet and regimen by each physical constitutions could be implemented, it is certain that the health could be maintained and promoted. And, what we are healthy is for oneself to feel it subjectively. However, I think that cholesterol score in blood that we can view objectively could be changed distinctly if we can implement a strict diet and regimen. Accordingly, it is necessary for a method and period of experiment to be more strict and longer. According to the above results, I would like to suggest as follows. 1) In order to understand health status by Korean's physical constitutions and to generalize it, these research will be repeated against much more objects that could be selected by proper grouping method to consider a representative. 2) It is necessary for a research to inspect health status by physical constitution by developing a health status measurement tool that has higher confidence and propriety based on physical constitutional theory.

• Korean Journal of Poultry Science
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• v.36 no.2
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• pp.117-123
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• 2009

This work was conducted to evaluate the effects of induced-molting methods on visceral organs and blood stress indicators in laying hens. One hundred fifty of 63-wk-old White Leghorn hens, with over 85% of egg production and $1.7\;{\pm}0.4\;kg$ of average weight, were used in this study. Treatments were control (non-molt treatment), feeding molt treatment (FM), and starving molt treatment (SM). There were 5 replicates of 10 hens for each treatment. All treatment groups were fed basal diet (15% CP and 2,700 kal/kg of ME) for two weeks as adaptation period. Heart weights were 8.2, 7.9 and 7.5 g in control, FM and SM, respectively. Liver and oviduct weights were decreased in both molting treatments compared with control (P<0.05). Corticosterone (CS) concentrations were 4.48, 4.47 and $4.66\;{\mu}g/mL$ in control, FM and SM at 61 weeks, respectively, but increased to 7.32, 7.11 and $7.71\;{\mu}g/mL$ at 62 weeks, respectively (P<0.05). Heterophil to lymphocyte ratios were 0.27~0.29 in all groups at 61 weeks, but increased to 0.97~1.03 in SM at 62 weeks. Both CS concentrations and H:L ratios in SM were greater compared with those for the other groups. These results suggest that hens in feeding molting program in hens are less stressed than those in starving molting one.