• Journal of Broadcast Engineering
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• v.19 no.4
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• pp.491-501
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• 2014

Recently, the need for disaster-preventing broadcast has increased gradually to cope with natural disaster like earthquake and tsunami causing enormous losses of both life and property. In disaster-preventing broadcast system, the wake-up signal is used to alert user terminal and switch the current state of channel to the emergency channel, which is for the fast and efficient delivery of emergency information. In this paper, we propose the detection method of wake-up signal for disaster-preventing broadcast systems. The wake-up signals for disaster-preventing broadcast should have a good auto-correlation property in low power and narrow-band conditions that does not affect the existing digital television (DTV) system. The suitability of the m-sequence and complementary code (CC) is analyzed for wake-up signals according to signal to noise ratio. A wake-up signal is proposed by combining the direct sequence spread spectrum (DSSS) technique and pseudo noise (PN) sequences such as Barker and Walsh-Hadamard codes. By using the proposed method, a higher detecting performance can be achieved by the spreading gain compared to the single long m-sequence and the Golay code.

• The Journal of the Korea Contents Association
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• v.18 no.9
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• pp.294-307
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• 2018

The aim of this study is to find out how married women who had had an abortions experience a change through Family Constellation. The consequent changes will occur in the perception of an abortion experience and in the relation between married women themselves and their family. The participants in the study were 9 married women aged 40~60 who have experienced an abortion, and data collection was carried out over 3 periods which were before, right after and one month after the Family Constellation experience through individual in-depth interviews. The chief methodology of this study is based on the one by Colaizzi's phenomenological research, and by using the methodology to analyze the data 15 theme collections and 3 categories were deducted. According to the result of the analysis, the experience of abortion was having negative influence on the whole spectrum of the life of married women who experienced an abortion even though they did not consciously recall the relevant experiences. In the married women's Family Constellation, the agent visualizes the restrained relation which is hidden in unconsciousness and thereby offers an opportunity for married women to untie "knot". Moreover through this opportunity, married women are able to have new perception of their abortion experience and the relation between their family. Furthermore, not only will they be able to recover the relationship with their family, but also emotional stability.

• Journal of Korean Neurosurgical Society
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• v.43 no.6
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• pp.265-269
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• 2008

Objective : Outcome of gamma knife radiosurgery (GKS) in the consecutive 100 cases with cerebral arteriovenous malformations (AVMs) was analyzed. Methods : Data from initial 100 patients treated with GKS in the authors' institute were reviewed retrospectively. Spetzler-Martin grade at diagnosis were I in 18 patients, II in 27, III in 36, IV in 11, and V in 8. Thirty-five patients had experienced previous bleeding, 27 patients presented with seizure, and 31 patients presented with headache. The mean volume of the lesion was $4.3\;cm^3\;(0.1-29.3\;cm^3)$. The median radiation dose delivered to the margin was 20.0Gy (13-32Gy). Mean follow-up period was 37.5 months (5-63 months). Results : Angiographic follow-up was performed in 48 patients at least 2 years after GKS. Sixteen patients were lost in follow up following 2 years from GKS. Twenty-eight of 48 patients (58%) showed complete obliteration and 20 patients (42%) showed partial obliteration. Seven patients presented with post-GKS hemorrhage. Adverse radiation effect (ARE) was observed at follow-up MRI in 25 of 76 patients, and it was symptomatic in 5 patients. Complete obliteration was confirmed in 24 of 31 (77%) patients with volume less than $4\;cm^3$, meanwhile only 4 of 17 (24%) patients with volume of $4\;cm^3$ or more showed complete obliteration. Complete obliteration rate was 67% with 20Gy or higher marginal dose, 63% with 15-20 Gy, and 17% with less than 15Gy. Conclusion : GKS can provide high rates of obliteration with acceptable risk of morbidity in a subgroup of small AVMs. However, overall outcome in whole spectrum of AVMs, in which large proportion of cases have unfavorable characteristics for radiosurgery, is much worse. More effective therapeutic strategy needs to be developed for large AVMs that are difficult to be managed with current available treatment modalities.

• Journal of the Korean association of regional geographers
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• v.20 no.4
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• pp.454-472
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• 2014

This study is to analyze the approaches of development discourse and its representation in geography curriculum and textbooks for middle school in Korea. The paper examines the spectrum of development discourse in terms of modernization theory, dependency theory, neoliberalism, grassroots development, sustainable development, postcolonism, post-structuralism and post-development. The findings on geography textbook analysis based on them are as follows. First, Most of the textbooks don't include the definition and operational definition on development and sustainable development. Second, development indicators rely on normal economic indicators like GDP or GNI per capita. HDI that includes GDP per capita, level of education and life expectancy is treated in some of the textbooks, and gender index is never presented. Third, a textbook still uses biased terms such as developed and most developed countries instead of developing countries. Fourth, in plans to solve economic unequality and geographical problems, personal level is treated less than the global, nation and NGOs. Finally, statements on sustainable development contain only intergenerational equity, not intergenerational equity. And approaches on sustainable development are based on technocentric approaches more than ecocentric approaches. Thus geography textbooks should be carefully written on development discourse by authors.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.71-76
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• 2008

Purpose: A simple and efficient method to prepare nanocrystalline ZnO thin film with pure strong UV emission on soda-lime-silica glass substrates by low-temperature annealing was improved. Methods: Crystal structural, surface morphological, and optical characteristics of nanocrystalline ZnO thin films deposited on soda-lime-silica glass substrates by prefiring final annealing process at 300$^{\circ}C$ were investigated by using X-ray diffraction analysis, field emission-scanning electron microscope, scanning probe microscope, ultraviolet-visible-near infrared spectrophotometer, and photoluminescence. Results: Highly c-axis-oriented ZnO films were obtained by prefiring at 300$^{\circ}C$. A high transmittance in the visible spectra range and clear absorption edge in the ultra violet range of the film was observed. The PL spectrum of ZnO thin film with a deep near band edge emission was observed while the defect-related broad green emission was nearly quenched. Conclusions: Our work will be possibly adopted to cheaply and easily fabricate ZnO-based optoelectronic devices at low temperature, below 300$^{\circ}C$, in the future.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.427-434
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• 2008

Processing of collagen from yellowfin tuna (Thunnus albacares) abdominal skins was optimized by response surface methodology and central composite design. The values of independent variables at optimal conditions were NaOH concentration: 0.5 N, NaOH treatment time: 36.2 hr, pepsin concentration: 1:4.9 ratio (0.245%, w/v), and digestion time: 48.1 hr, respectively. The collagen content estimated under optimal conditions was 33.1%, and the actual experimental collagen content was 32.3%. Physicochemical properties of collagen from yellowfin tuna abdominal skin were investigated by amino acids analysis, SDS-PAGE, FT-IR, viscosity and denaturation temperature. Amino acids content of the collagen was 21.0%. SDS-PAGE pattern of the collagen showed two different $\alpha$-chain (${\alpha}_1$- and ${\alpha}_2$- chain), $\beta$-component and $\gamma$-component. The spectrum of FT-IR of the collagen showed wavenumber at 3,434, 1,650, 1,542 and $1,235\;cm^{-1}$ representing the regions of amide A, I, II and III, respectively. Relative viscosity of the collagen decreased continuously on heating up to $32^{\circ}C$, and the rate of decrease was retarded in the temperature range of $35-50^{\circ}C$. Denaturation temperature (Td) of the collagen solution (0.06%, w/v) was $31^{\circ}C$ and was lower than calf skin collagen ($35^{\circ}C$).

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.792-797
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• 2015

Graphene has a wide spectrum on its application field due to various and excellent physical properties. However, it is very difficult to apply that graphene exists as lump or fold condition in general organic solvents. Besides, graphene was difficult to maintain as uniform condition due to chemical inert and distributions with various size and shapes. Therefore, this study was focused to study dispersion and modifying methods of aggregated graphene. The dispersion methods contain as follow: i) physical milling using glass bead, ii) co-treatment of glass bead and ultrasonic waves, iii) dispersion in organic solvents, iv) modifying with dry-ice. Milling using glass bead with size 2.5 mm was effective to be size decrease of 36.4% in comparison with control group. Mixed treatment of glass bead (size 2.5 mm) and ultrasonic waves (225W, 10 min) showed relative size decrease of 76%, suggesting that the size decrease depends on the size of glass bead, intensity of ultrasonic waves and treatment time. Solvents of Ethyl acetate (EA) and Isoprophyl alcohol (IPA) were used in order to improve dispersion by modifying surface of graphene. IPA of them showed a favorable dispersion with more -CO functional groups in the FT-IR analysis. On the other hand, the oxygen content of graphene surface modified by dry-ice was highly increased from 0.8 to 4.9%. From the results, it was decided that the favorable dispersion state for a long time was obtained under the condition of -CO functional group increase in IPA solvent.

• Resources Recycling
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• v.27 no.1
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• pp.84-91
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• 2018

In this study, a novel soft information based most probable classification scheme is proposed for sorting recyclable metal alloys with laser induced breakdown spectroscopy (LIBS). Regression analysis with LIBS captured spectrums for estimating concentrations of common elements can be efficient for classifying unknown arbitrary metal alloys, even when that particular alloy is not included for training. Therefore, partial least square regression (PLSR) is employed in the proposed scheme, where spectrums of the certified reference materials (CRMs) are used for training. With the PLSR model, the concentrations of the test spectrum are estimated independently and are compared to those of CRMs for finding out the most probable class. Then, joint soft information can be obtained by assuming multi-variate normal (MVN) distribution, which enables to account the probability measure or a prior information and improves classification performance. For evaluating the proposed schemes, MVN soft information is evaluated based on PLSR of LIBS captured spectrums of 9 metal CRMs, and tested for classifying unknown metal alloys. Furthermore, the likelihood is evaluated with the radar chart to effectively visualize and search the most probable class among the candidates. By the leave-one-out cross validation tests, the proposed scheme is not only showing improved classification accuracies but also helpful for adaptive post-processing to correct the mis-classifications.

• International Journal of Highway Engineering
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• v.9 no.2 s.32
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• pp.115-127
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• 2007

Developed countries, especially in road construction and management fields, introduce new road porjects such as National Scenic Byways Program(NSBP program) in USA and the Eco-road project in Japan. This study develops a conceptual model for deploying new road projects in Korea. The four step approach is suggested to create new road projects, including foundation of an act based on the existing Road Act, creation of new road project ideas, development of evaluation process and guidelines, and enhancement of an administrative scheme. To create new road projects, three different ways are devised; (1) designation of national roads having uniqueness in overall spectrum, (2) designation of roads having intrinsic values in a different aspect, (3) designation of single structures of engineering outcomes such as bridges, tunnels, new design techniques, considerable Value Engineering output, and well analyzed Life Cycle Cost Analysis practices. For the evaluation process, NSBP program of USA and/or Sustainable City Award program of Korea would be recommended. An administrative scheme and integrated funding process for the new road projects are also suggested based on evaluation of tasks of each team or division of Korea Ministry of Construction and Transportation.

• Journal of Korean Society of Rural Planning
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• v.20 no.3
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• pp.75-88
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• 2014

The purpose of the present study is to examine the characteristics of intermediary organizations for rural tourism by analyzing how they are run, especially in Yangpyeong-gun and Icheon-si Nadri groups, and to further look for the desirable role they should play. Since the activities of these intermediary groups have not been accumulated enough to be able to be used for a study, grounded theory was adopted as deemed appropriate among other qualitative research approaches for this paper. Three main findings of the current research are as follows. First, the rural tourism intermediary organizations have characteristics that are leaning towards local villages more than visitors, although they are in the middle of a spectrum stretching between 'visitors to the green villages' on one end and the 'green villages' on the other end. Second, the intermediary groups work not just as a bridge among different green villages but also as a mediator, facilitator and a guide, noting that such roles can vary significantly depending on the level of competence of the groups themselves and the extent to which the government steps in. Third, the tourism intermediary organizations can contribute to local community-building, going beyond the boundaries of green village. They help to improve the quality of tour experience which leads to revitalization of local economy, and during the course of operating the intermediary groups, the community in the village can set up rules and resolve disputes and conflicts. Thus, the activities of the groups have the potential to create a local community by affecting not just at a village level but to a broader area where their operation is based on. Implications of this study are suggested in three ways. First, the paper looked at the interaction between rural tourism intermediary organizations and stakeholder in a comprehensive way with a qualitative research approach taken. Second, it identified the role and tasks of rural tourism intermediary organizations. Third, it is important to ensure that the tourism intermediary organizations play the local community-oriented role.