• Korean Journal of Materials Research
• /
• v.16 no.6
• /
• pp.341-345
• /
• 2006

[ $Ni_2Si$ ] mixed powders were mechanically alloyed by a ball mill and then processed by hot isostatic pressing (HIP) and spark plasma sintering (SPS). In the powder that was mechanically alloyed for 15minutes(MA 15 min), only Ni and Si were observed but in the powder that was mechanically alloyed for 30minutes(MA 30 min), $Ni_2Si$, Ni and Si were mixed together. Some of the MA 15 min powder and MA 30 min powder were processed by HIP under pressure of 150MPa at the temperature of $1000^{\circ}C$ for two hours and some of them were processed by SPS under pressure of 60 MPa at the temperature of $1000^{\circ}C$ for 60 seconds. Both methods completely compounded the powders to $Ni_2Si$. The maximum density of sintered lumps by HIP method was 99.5% and the maximum density of the sintered lump by SPS method was 99.3%. with the hardness of HRc 66 with the hardness of HRc 63. Therefore, the SPS method that can sinter in short time at low cost is considered to be more economical that the HIP method that requires complicated sintering conditions and high cost and the sintering can produce target materials in desired sizes and shapes to be used for thin film.

• Journal of Korean Medicine for Obesity Research
• /
• v.17 no.2
• /
• pp.119-126
• /
• 2017

Objectives: This study investigated the effects of the mixed herbal extract from Cinnamomum cassia Blume, Atractylodes macrocephala Koidzumi, Pueraria lobata Benth, and Aconitum carmichaeli Debx (CAPA) on obesity and glucose tolerance in obese mice. Methods: Animals were divided in 6 groups, normal diet, high fat diet (HFD), HFD with CAPA 100 mg/kg (CAPA 100), CAPA 300 mg/kg (CAPA 300), and metformin 200 mg/kg or lorcaserin 10 mg/kg as positive controls, and treated for 16 weeks. Body weight, food intake, fasting blood glucose, and body temperature were checked every week and then organs, blood serums were collected after treatment. The oral glucose tolerance test was also carried out after treatment. Results: Compared to HFD, CAPA extract treated mice showed significant decreases in body weight, adipose tissue weight, lipid accumulations in liver and serum lipid levels without a reduction of food intake. And fasting glucose and glucose tolerance were all improved in the CAPA treated mice. Conclusions: Our results suggest that CAPA extract can prevent diet induced obesity and glucose intolerance without a reduction of energy intake in obese mice.

• Journal of Forest and Environmental Science
• /
• v.37 no.2
• /
• pp.128-140
• /
• 2021

Tropical dry forests are one of the most threatened, widely distributed ecosystems in tropics and estimation of forest biomass is a crucial component of global carbon emission estimation. Therefore, the present study was aimed to quantify the biomass and carbon storage in trees on large scale (10, 1 ha plots) in the dry mixed evergreen forest of Javadhu forest of Eastern Ghats. Biomass of adult (≥10 cm DBH) trees was estimated by non-harvest methods. The total biomass of trees in this tropical dry mixed evergreen forest was ranged from 160.02 to 250.8 Mg/ha, with a mean of 202.04±24.64 Mg/ha. Among the 62 tree species enumerated, Memecylon umbellatum accumulated greater biomass and carbon stocks (24.29%) more than the other species in the 10 ha study plots. ANOVA revealed that there existed a significant variation in the total biomass and carbon stock among the three plant types (Evergreen, brevi-deciduous and deciduous (F (2, 17)=15.343, p<0.001). Basal area and density was significant positively correlated with aboveground biomass (R² 0.980; 0.680) while species richness exhibited negative correlation with above ground biomass (R² 0.167). Finding of present study may be interpreted as most of the trees in this forest are yet to be matured and there is a net addition to standing biomass leading to carbon storage.

• Journal of Forest and Environmental Science
• /
• v.37 no.4
• /
• pp.269-279
• /
• 2021

This study was carried out to introduce the forest cover types of the Baekdudaegan inhabiting the number of native tree species. In order to understand the vegetation distribution characteristics of the Baekdudaegan, a vegetation survey was conducted on the major 20 mountains of the Baekdudaegan. The vegetation data were collected from 3,959 sample points by the point-centered quarter method. Each mountain was classified into 4-7 forests by using various multivariate statistical methods such as cluster analysis, indicator species analysis, multiple discriminant analysis, and species composition analysis. The forests were classified mainly according to the relative abundance of Quercus mongolica. There was a total of 111 classified forests and these forests were integrated into the following nine forest cover types using the percentage similarity index and by clustering according to vegetation type: 1) Mongolian oak, 2) Mongolian oak and other deciduous, 3) Oaks (Mixed Quercus spp.), 4) Korean red pine, 5) Korean red pine and oaks, 6) ash, 7) mixed mesophytic, 8) subalpine zone coniferous, and 9) miscellaneous forest. Forests grouped within the subalpine zone coniferous and miscellaneous classifications were characterized by similar environmental conditions and those forests that did not fit in any other category, respectively.

• Journal of Engineering Education Research
• /
• v.25 no.2
• /
• pp.32-41
• /
• 2022

The purpose of this study was in a pandemic situation caused by COVID-19 to explore the online distance experiments and interaction of engineering freshmen, and to identify practical difficulties, resulting in to derive implications. Seven freshmen from engineering college participated in the interview, of which data were analyzed based on phenomenological analysis methods. The types of non-face-to-face experiments experienced by students were complete non-face-to-face experiment, mixed face-to-face experiment, and fusion face-to-face experiment. Students were completely isolated in time and space in complete non-face-to-face experiment. In biweekly mixed face-to-face experiment, isolation was halved. In fusion face-to-face experiment, isolation was removed. Non-face-to-face interactions can be characterized by restrictions on simultaneous activities, on rapport formation, and on observation opportunities. Based on these results, three implications were derived: First, it is necessary to allow students to manage time and space constraints on their own in non-face-to-face experiments. Second, support is needed to solve the difficulty of forming rapport, which is a characteristic of non-face-to-face interaction. Third, an opportunity to observe the interaction between other students and professors should be provided.

• Nuclear Engineering and Technology
• /
• v.37 no.1
• /
• pp.25-78
• /
• 2005

As a key and core knowledge for the design of various types of nuclear reactors, the discipline of reactor physics has been advanced continually in the past six decades and has led to a very sophisticated fabric of analysis methods and computer codes in use today. Notwithstanding, the discipline faces interesting challenges from next-generation nuclear reactors and innovative new fuel designs in the coming. After presenting a brief overview of important tasks and steps involved in the nuclear design and analysis of a reactor, this article focuses on the currently-used design and analysis methods, issues and limitations, and current activities to resolve them as follows: (1) Derivation of the multi group transport equations and the multi group diffusion equations, with representative solution methods thereof. (2) Elements of modem (now almost three decades old) diffusion nodal methods. (3) Limitations of nodal methods such as transverse integration, flux reconstruction, and analysis of UO2-MOX mixed cores. Homogenization and related issues. (4) Description of the analytic function expansion nodal (AFEN) method. (5) Ongoing efforts for three-dimensional whole-core heterogeneous transport calculations and acceleration methods. (6) Elements of spatial kinetics calculation methods and coupled neutronics and thermal-hydraulics transient analysis. (7) Identification of future research and development areas in advanced reactors and Generation-IV reactors, in particular, in very high temperature gas reactor (VHTR) cores.

• The Journal of the Korea Contents Association
• /
• v.10 no.11
• /
• pp.169-179
• /
• 2010

In these days, space design is evolving to the mixed reality space where fused on-line and off-line. But, standard and measure of mixed reality space has not been suggested and there has been little research about media environment and expression method as a mixed system either. That's why here I suggest four media environments and their characteristics that act not only as a critical point in the mixed reality space based on ubiquitous technology but also as a standard for spatial discerning. 1) Real space that is a media environment only seen by human visual and tactical sense is evolving using expression methods like new materials based on digital technology and LED. 2) Augmented reality space is a media environment using information instruments is expressed with diverse 2D and 3D contents. 3) Cyber Space is a environment depends totally on media instruments is produced by perfect graphic information without any spatial and physical limitations. 4) Augmented cyber space is realized only through the displays in cyber studio and is a space where real objects and graphic information are mixed. Depending on the purpose of the experience, media environment and expressional characteristics of mixed reality space can be fused, blended, and mixed, and that can be realized to the intelligent information space where one can experience without spatial, visual, informational limitations. In the future, studies on physical characteristics of contents according to the media environment characteristics are necessary.

• The Journal of Industrial Distribution & Business
• /
• v.12 no.1
• /
• pp.31-46
• /
• 2021

Purpose: The purpose of the study is to analyze the characteristics of emotional intelligence and the variables related to emotional intelligence in a comprehensive manner. In addition, the study intends to present research trends and future research directions of emotional intelligence in a Korean context by analyzing the effects of emotional intelligence and its mechanisms. Research Design, Data, and Methodology: 77 KCI listed studies were selected for the analysis, and the research perspective of emotional intelligence, measurement instruments, empirical research and research methods were analyzed. In addition, research directions were suggested based on the analysis results. Results: The results of the analysis were as follows: First, previous researchers used the ability model of emotional intelligence the most. Second, Previous studies tended to focus on behavioral factors as dependent variables affected by emotional intelligence, in addition to attitudes, affection. Third, there were few studies on the antecedents of emotional intelligence, however, most studies dealt with the consequences of emotional intelligence. Fourth, few studies dealt with moderators between emotional intelligence and dependent variables. Fifth, on the research type, most studies were quantitative studies, however, a few of them were qualitative studies (Literature review, in-depth interview). Sixth, with regard to the analysis level, almost all studies were conducted on the individual level of emotional intelligence, and most studies featured a cross-sectional research design (longitudinal research design was rare). Conclusion: First, from the perspective of emotional intelligence, additional research should be focused on not only the ability model of emotional intelligence but also on the trait model or the mixed model in the future. Second, since emotional intelligence is a multidimensional construct, it is necessary to study the profile of emotional intelligence by employing people-centered as well as variable-centered methods. Third, with regard to empirical studies, additional research is needed with respect to not only the emotional intelligence of the subordinate, but also the emotional intelligence of the supervisor (leader) and the emotional intelligence of the group. Fourth, it is necessary to actively utilize not only cross-sectional design but also longitudinal design, and qualitative research and meta-analysis methods should also be adopted.

• Journal of Information Science Theory and Practice
• /
• v.10 no.4
• /
• pp.87-109
• /
• 2022

Previous studies have found that the use or development of theory in library and information science (LIS) research is comparatively low and may be trending downward. LIS has also been criticized for relying on theories imported from other disciplines rather than applying or developing theories from within. The theory of information worlds, a social information behavior theory originally introduced in 2008, represents a newer LIS theory whose level of adoption is understudied. This study features a systematic literature review of peer-reviewed research articles which cited or used the theory of information worlds from 2008 to early 2022 to identify trends related to levels of theory use, publication venues, author affiliations, countries, and collaborations, as well as research methods, topics, and populations. Findings suggest that both awareness and use of the theory of information worlds are positively trending, though at slower rates for higher levels of theory use, such as full applications of the theory to guide the collection and analysis of empirical data. The theory has also been used by researchers from around the world and across disciplines, most often with mixed and qualitative methods. While the growth of a new LIS theory is promising, the authors echo calls for increased use and development of the theory of information worlds, and other LIS theories more broadly, and as more interdisciplinary collaboration.

• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.7
• /
• pp.509-516
• /
• 2021

This study aims to find out and measure the level of factors affecting the applicability of environmental management accounting (EMA) in Vietnamese automobile industry enterprises. Data was collected using both quantitative and qualitative methods. First, in general research, qualitative methodology was used to find out factors (variables) that can impact the possibility of implementing EMA in Vietnamese automobile enterprises. Second, in detailed research, all variables are measured using a quantitative method by collecting data through sampling and sending questionnaires. 500 questionnaires were sent to automobile enterprise managers and only 352 questionnaires met the criteria for the data analysis. The study used a mixed research design approach- a procedure for collecting, analyzing, and "mixing" both quantitative and qualitative research and methods in a single study to understand the research problem. Results show that 7 factors affect the possibility of implementing EMA in Vietnamese automobile industry enterprises. These factors are coercive pressure, normative pressure, mimetic pressure, business environmental uncertainty, environmental strategy, benefits when applying EMA, and task complexity. Based on the results of the study, promoting EMA in the automotive industry should depend mainly on the role of governmental departments.