• The Journal of Korean Academy of Prosthodontics
• /
• v.49 no.3
• /
• pp.254-262
• /
• 2011

Purpose: This study aims to evaluate and prospect for current research trend and developmental perspectives via analyzing recent biomaterial coated-implants study. Materials and methods: To investigate each subject respectively, several biomaterials that are using for implant surface coating were set as 'keywords'. By these keywords, major research groups in each subject were chosen, and research trend of them was analyzed. Trend of In vivo studies that examined selected biomaterials were analyzed to evaluate commercial potential. Results: The collagen research accounted for 40% of total implant study, which was the highest, and fibronectin, BMPs (bone morphogenetic proteins) and RGD (Arg-Gly-Asp) peptides followed, which were ranked in descending order. Furthermore, figures of all four research subjects were also increased with time, especially a sharp increase in RGD research. According to the results of major research group, collagen that was combined with other organic and inorganic biomaterials was mostly examined, rather than using collagen only. Major research groups investigating BMPs mostly focused on rhBMP-2. In animal studies, collagen was used as resorbable membrane in guided bone regeneration (GBR) or drug carrier, while BMPs were used with bone graft materials or coating material for titanium implant surface. Conclusion: There is not consistency of results even in identical subjects research field. Many studies are ongoing to optimize combination between mechanical surface treatment and biomaterials such as extracellular matrix component and growth factors.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.39 no.3
• /
• pp.64-73
• /
• 2011

This study starts from the hypothesis that the information society has affected the layman's interpretation and production of content. Specifically, the manner and contents of communication concerning the landscape of Soonyoo-do Park in blogs are surveyed and the possibilities and limitations of this phenomenon are discussed. The following topics are dealt with. Firstly, what is the landscape of Seonyoodo Park as captured by bloggers? What type of landscape do bloggers respond to? Secondly, what is the unique way that bloggers capture and interpret the landscape? Thirdly, What are the possibilities and limitations discovered from the landscape as captured and interpreted by bloggers? Thus, 1,000 blog posts concerning Soonyoo-do Park, as culled from the Internet, were categorized into three areas, First are blog posts browsed by keywords such as 'photo', 'a photographer's visit', 'a good p1ace for taking photos', and 'landscape'. These are focused on the visual aspects of the landscape. The second category is posts under the keywords 'domestic travel', 'Seoul travel', 'travel', and 'recommendation'. They contain introductory information on Seonyoodo Park; that is, they focus cm the more utilitarian functions of Seonyoodo Park as a place. The third one is posts that record personal experiences. The subjects for photography are the bloggers themselves and their companions. As a result of studying the way bloggers deal with landscape, it was found that first, people have developed the ability to capture the landscape and interpret the landscape actively and independently. This process can be regarded as the reproduction of landscape and place. In addition, the recording of their appreciation and feeling overlaps with evaluation and assumption. One negative aspect, however, is that many bloggers dramatize and repeat similar scenes. This can be seen as a make-up of image. The limitations of this study include difficulty in interpretation because blogs, which are the objects of this study, are very subjective and personal. In addition, it was not easy to categorize posts because there were diverse images and a broad range of writing. Nevertheless, practitioners of landscape architecture should continue to monitor and use one-person media like blogs, because the relationship between modern man and the landscape can be better understood through them.

• Journal of the Korean association of regional geographers
• /
• v.19 no.2
• /
• pp.324-339
• /
• 2013

This study aims to investigate the characteristics of cyber communities composed of migrant workers from communities without propinquity in Korea. Its methods are both qualitative and quantitative. It further seeks to discover the relationship between the social capital formed and reproduced within these cyber communities and participants' cultural adaptation to Korean society. The study revealed that ethnic and non-ethnic communities differed in terms of strength of cohesion, space constraints, and links with the outside world. The former showed characteristics of a localized community type. The main motivations for migrant workers' participation in the ethnic cyber community were communication and friendship rather than cooperation and sharing among members. They usually used cyber communication media to communicate with one another. Conversely, the latter showed characteristics of an integrative type. Despite the difficulties in applying for membership and information provided in Korean, a high percentage of migrant workers participated in the community to obtain crucial information. The results did not show a significant correlation between social capital and migrant workers' traits within the cyber community, while a strong correlation emerged among four factors of social capital: faith, norms, networking, and political participation. The study showed that social capital in the cyber community was in direct proportion to an integrative type of cultural adaptation to Korean society. In particular, there was a strong connection between the cultural adaptation exhibited by members of the migrant subculture and their participation in discussions on political issues and human rights, with some migrants even functioning as agents of social change as participants in citizens' movements. The findings suggest that the cyber community facilitates the migrant subculture's communication with and integration into the indigenous Korean culture. Migrant workers' participation in the cyber community is therefore validated as an instrumental practice for members of this subculture to adapt to Korean society.

• Journal of Nutrition and Health
• /
• v.50 no.2
• /
• pp.180-191
• /
• 2017

Purpose: The purpose of the study was to identify teacher's knowledge about sodium, dietary behaviors related to sodium, attitudes towards a low-salt diet, and meal attitude guidance as well as examine the relationship between these variables. Methods: The participants were 351 teachers at an elementary school in the Jeonbuk area. The data were analyzed using ANOVA, Duncan test, and Pearson correlation coefficients with SPSS v. 20.0. Results: The score for teachers' knowledge about sodium was 12.92 points of a possible 16, the score for dietary behavior related to sodium was 46.85 points of a possible 70, and the score for attitude towards a low-salt diet was 33.63 points of a possible 50. Their score for meal attitude guidance was 59.95 points of a possible 80. The knowledge showed significant differences by hypertension drug (p < 0.05) and stress level (p < 0.05). The dietary behavior of sodium use showed significant differences by gender (p < 0.01), work experience (p < 0.05), BMI (p < 0.01), drinking (p < 0.05), concern about health (p < 0.05), and stress level (p < 0.05). The attitude towards a low-salt diet showed significant differences by gender (p < 0.05), marital status (p < 0.05), work experience (p < 0.05), drinking (p < 0.05), concern about health (p < 0.001), and stress level (p < 0.05). Meal attitude guidance showed a significant difference by marital status (p < 0.001), age (p < 0.001), work experience (p < 0.001), drinking (p < 0.01), regularity of health checkup (p < 0.001), concern about health (p < 0.001), and stress level (p < 0.05). There was a low positive correlation between knowledge about sodium and dietary behavior related to sodium as well as between dietary behavior related to sodium and attitudes towards a low-salt diet. Attitudes towards a low-salt diet showed a positive correlation with meal attitude guidance. Conclusion: Therefore, it is necessary to consider educational programs on increasing knowledge and attitudes towards a low-salt diet in teachers for improvement of meal attitude guidance activities for students.

• Journal of the Korean Wood Science and Technology
• /
• v.42 no.4
• /
• pp.428-438
• /
• 2014

Functional effects of cauliflower mushroom (Sparassis latifolia) have been magnified by various media and internal and external research papers, recently. So, optimum condition of wood chip particle size and cultivation method of high ${\beta}$-glucan content for bulk cultivation generalization of cauliflower mushroom farms researched. As a result, T7 (1~2 mm 25%, 2~4 mm 50%, over 4 mm 25%) media as mixed media of certain ratio of particle size, showed excellent growth at $11.5{\pm}1.0$ cm / 44 days. Also, production of fruit body found higher than control and marketable pileus part took 85% ratio. The ${\beta}$-glucan content at media composition condition showed 1.4~2.4 times higher content in stipe part than pileus part. Also, PCF300 medium found 59.5% highest ${\beta}$-glucan content in stipe part. While ${\beta}$-glucan content showed 33.0% low content in pileus part. Therefore it needed additional study that ${\beta}$-glucan content improved in pileus part. In conclusion, production of high ${\beta}$-glucan content cauliflower mushroom was possible by T7 condition (wood chip particle size: 1~2 mm 25%, 2~4 mm 50% and over 4 mm 25%, composition: corn powder, flour and 300 ppm yeast).

• Journal of Soil and Groundwater Environment
• /
• v.13 no.4
• /
• pp.8-21
• /
• 2008

A series of three-dimensional numerical simulations using a hydrodynamic dispersion numerical model is performed to analyze quantitatively impacts of layered heterogeneity of geologic media and groundwater pumping schemes on groundwater flow and salt transport in coastal aquifer systems. A two-layer heterogeneous coastal aquifer system composed of a lower sand layer (aquifer) and an upper clay layer (aquitard) and a corresponding single-layer homogeneous coastal aquifer system composed of an equivalent lumped material are simulated to evaluate impacts of layered heterogeneity on seawater intrusion. In addition, a continuous groundwater pumping scheme and two different periodical groundwater pumping schemes, which withdraw the same amount of groundwater during the total simulation time, are applied to the above two coastal aquifer systems to evaluate impacts of groundwater pumping schemes on seawater intrusion. The results of the numerical simulations show that the periodical groundwater pumping schemes have more significant adverse influences on groundwater flow and salt transport not only in the lower sand layer but also in the upper clay layer, and groundwater salinization becomes more intensified spatially and temporally as the pumping intensity is higher under the periodical groundwater pumping schemes. These imply that the continuous groundwater pumping scheme may be more suitable to minimize groundwater salinization due to seawater intrusion. The results of the numerical simulations also show that groundwater salinization in the upper clay layer occurs significantly different from that in the lower sand layer under the periodical groundwater pumping schemes. Such differences in groundwater salinization between the two adjacent layers may result from layered heterogeneity of the layered coastal aquifer system.

• The korean journal of orthodontics
• /
• v.29 no.4 s.75
• /
• pp.445-456
• /
• 1999

As a result of increased education and communication, the field of orthodontics has recently been expanded to include a greater number of adult treatment procedures. With this increased demand for adult orthodontic treatment, a problem that frequently arises is the placement of appliances on teeth restored with porcelain. But conventional acid-etching is ineffective in the preparation of porcelain surface for mechanical retention of orthodontic attachments. Also, it is possible to damage on porcelain. The purpose of this study was to evaluate the effect of composite bonding materials and the porcelain surface treatment methods on shear bond strength, and to observe the porcelain fracture rates. To accomplish this purpose, this study was carried out with feldsphatic porcelain, Ceram II. Porcelain surface treatment methods were divided into intact glazed porcelain which had not treatment and surface roughening. Surface roughening by etching with Hydroluoric acid(HF), sandblasting with Microetcher II and compound treatment with etching and sandblasting. Bonding materials were Ortho-two and Transbond. All porcelain specimens were applicated with porcelain primer. 1. In comparision according to porcelain surface treatment, surface roughening groups by HF etching and sandblasting had higher shear bond than intact group. No significant difference was found in Transbond group. 2. Ortho-two group had the higher shear bond strength than that of Transbond group in B:.u etching and sandblasting. 3. E(Transbond. Intact)group had the lowest shear bond strength in all experimental group. The bond strength was higher than clinically successful bond strength. 4. Non-treated group had very higher porcelain rates than treated group. 5. This study indicates that porcelain surface-roughening may not be necessary to attachment of orthodontic brackets to porcelain surfaces.

• Journal of Science and Technology Studies
• /
• v.5 no.1 s.9
• /
• pp.93-123
• /
• 2005

This work has following two research goals. First, IVF treatments that have been recently going on in Korea are reexamined from the perspective of women's reproductive rights. Second, the intimate connection between IVF and therapeutic cloning research, in that remnant embryos and eggs that have been secured through IVF treatments have served as a main source of supply for therapeutic cloning research, has been emphasized. The fact that the influencing power of tradition on Korean families and women and IVF techniques eventually joined their hands in support of therapeutic cloning research is noted. Analysis of experiences of infertility by women in the realms of family, medical care during IVF treatment, and therapeutic cloning research that requires continuous supply of eggs leads to following conclusions. First, in the realm of family, infertile women were not only relegated to the status of abnormality but pressured to question their own womanhood. Under this circumstance, IVF treatment helped to reinforce the traditional concept of biological motherhood, thus categorizing married women giving birth to babies and married women who can't or refuses to do so to 'normal ones' and 'abnormal ones' respectively. Second, in the realm of medical care an infertile woman could rediscover her own body during the process of IVF treatment. By going through the processes of hormone treatment, implantation, conception, miscarriage, and so on, she could realize that her own body is understood in diverse ways to her, her family, and the medical profession. Third, in the realm of the state, IVF treatment that was serving as the main supplier of research materials for therapeutic cloning research has been able to avoid controversy in public discourses since the latter has emerged as a signifier of new national economic workhorse for the 21st century. As therapeutic cloning research went into high gear, the status of women as egg providers began to assume a political dimension. Women as egg providers are called upon to take on a paradoxical role as patriotic contributors to national economy on the one hand and as guardians of sacred 'life' on the other hand. The direction and progress of the research will depend on the ways that women comply, compromise, and/or resist the contradiction brought about by being assigned to assume these two identities: the one as a member of the nation requested to serve as a part of national economic development project, even though considered ineligible for financial recompense, and the other one as a guardian of sacred 'life,' even though she have to serve the research that is allowed to create a 'life' to destroy a 'life.'

• Korean Chemical Engineering Research
• /
• v.46 no.3
• /
• pp.451-464
• /
• 2008

Three-phase inverse fluidized bed has been widely adopted with its increasing demand in the fields of bioreactor, fermentation process, wastewater treatment process, absorption and adsorption processes, where the fluidized or suspended particles are small or lower density comparing with that of continuous liquid phase, since the particles are frequently substrate, contacting medium or catalyst carrier. However, there has been little attention on the three-phase inverse fluidized beds even on the hydrodynamics. Needless to say, the information on the hydrodynamics and transport phenomena such as heat and mass transfer in the inverse fluidized beds has been essential for the operation, design and scale-up of various reactors and processes which are employing the three-phase inverse beds. In the present article, thus, the information on the three-phase inverse fluidized beds has been summarized and reorganized to suggest a pre-requisite knowledge for the field work in a sense of engineering point of view. The article is composed of three parts; hydrodynamics, heat and mass transfer characteristics of three-phase inverse fluidized beds. Effects of operating variables on the phase holdup, bubble properties and particle fluctuating frequency and dispersion were discussed in the section of hydrodynamics; effects of operating variables on the heat transfer coefficient and on the heat transfer model were discussed in the section of heat transfer characteristics ; and in the section of mass transfer characteristics, effects of operating variables on the liquid axial dispersion and volumetric liquid phase mass transfer coefficient were examined. In each section, correlations to predict the hydrodynamic characteristics such as minimum fluidization velocity, phase holdup, bubble properties and particle fluctuating frequency and dispersion and heat and mass transfer coefficients were suggested. And finally suggestions have been made for the future study for the application of three-phase inverse fluidized bed in several available fields to meet the increasing demands of this system.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.5C
• /
• pp.664-672
• /
• 2004

Widespread popularity of wireless data communication devices, coupled with the availability of higher bandwidths, has led to an increased user demand for content-rich media such as images and videos. Since such content often tends to be private, sensitive, or paid for, there exists a requirement for securing such communication. However, solutions that rely only on traditional compute-intensive security mechanisms are unsuitable for resource-constrained wireless and embedded devices. In this paper, we propose a selective partial image encryption scheme for image data hiding , which enables highly efficient secure communication of image data to and from resource constrained wireless devices. The encryption scheme is invoked during the image compression process, with the encryption being performed between the quantizer and the entropy coder stages. Three data selection schemes are proposed： subband selection, data bit selection and random selection. We show that these schemes make secure communication of images feasible for constrained embed-ded devices. In addition we demonstrate how these schemes can be dynamically configured to trade-off the amount of ded devices. In addition we demonstrate how these schemes can be dynamically configured to trade-off the amount of data hiding achieved with the computation requirements imposed on the wireless devices. Experiments conducted on over 500 test images reveal that, by using our techniques, the fraction of data to be encrypted with our scheme varies between 0.0244％ and 0.39％ of the original image size. The peak signal to noise ratios (PSNR) of the encrypted image were observed to vary between about 9.5㏈ to 7.5㏈. In addition, visual test indicate that our schemes are capable of providing a high degree of data hiding with much lower computational costs.