• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.138-150
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• 2003

In the mid-west coast of Korea where Mankyung and Dongjin rivers discharge fresh water, Saemangeum tidal dyke of 33 km long is under construction to reclaim the very shallow estuary region of 41,000ha. Main source of freshwater in this coastal area is Keum River locating closely north of the dyke. At present, the dyke connected with Gogunsan-Gundo separates this area into three regions; northwestern, southwestern and eastern (Saemangeum) region of the dyke, and the water in Saemangeum region is exchanged through one gap in the northern dyke and two gaps in the southern dyke. We have observed distributions and structures of temperature and salinity to examine the summer circulation related with low-salinity water in this coastal area in 1998 and 1999. In the surface layer off the northern dyke a tongue-like distribution of low-salinity extends 60 km long from Keum River estuary mouth to the northwest, forming plume front bounded by offshore water. In the inner region of Saemangeum dykes salinity distributions show that two river waters are merged together and the low salinity water is deflected toward northern gap of the dyke. In the surface layer off the southern dyke we observed small tongue-like distribution of another low-salinity water extending to the north from Gomso Bay. Based on the analysis of distributions of low-salinity water and frontal structures, we can suggest an anticlockwise circulation of coastal water around the dyke, composed by the estuarine water outgoing from the inner region of the dyke through the northern dyke's gap and the inflow through two gaps of southern dyke from offshore. After completing the dyke construction, this coastal circulation around the dyke will be, however, changed because fresh water discharge of Mankyung and Dongjin rivers will be routed artificially and directly into the area offshore of the southern dyke.

• The Journal of the Acoustical Society of Korea
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• v.21 no.2
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• pp.150-159
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• 2002

The possibility of a broadband noise reduction of piezoelectric smart panels is experimentally studied. Piezoelectric smart panel is basically a plate structure on which piezoelectric patch with shunt circuits is mounted and sound absorbing material is bonded on the surface of the structure. Sound absorbing materials can absorb the sound transmitted at mid frequency region effectively while the use of piezoelectric shunt damping can reduce the transmission at resonance frequencies of the panel structure. To be able to tune the piezoelectric shunt circuit, the measured electrical impedance model is adopted. Resonant shunt circuit composed of register and inductor in stories is considered and the circuit parameters are determined based on maximizing the dissipated energy through the circuit. The transmitted noise reduction performance of smart panels is investigated using an acoustic tunnel. The tunnel is a square crosses sectional tunnel and a loud speaker is mounted at one side of the tunnel as a sound source. Panels are mounted in the middle of the tunnel and the transmitted sound pressure across the panels is measured. Noise reduction performance of a double smart panel possessing absorbing material and air gap shows a good result at mid frequency region except the first resonance frequency. By enabling the piezoelectric shunt damping, noise reduction is achieved at the resonance frequency as well. Piezoelectric smart panels incorporating passive method and piezoelectric shunt damping are a promising technology for noise reduction in a broadband frequency.

• Clean Technology
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• v.20 no.4
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• pp.439-448
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• 2014

The potential mitigation of greenhouse gas (GHG) is studied in the Pohang steel industrial complex (PHSIC). The total GHG emission in 2010 is estimated to be in the range from 4,174,000 to 4,574,000 $tCO_2-eq$ in PHSIC. To meet the target proposed by the government, it is needed to reduce 552,000 $tCO_2-eq$ at minium by 2020. To estimate the potential amount of GHG reduction, the technologies used in the voluntary carbon reduction projects are applied to 51 companies which are subject to GHG target management. From the viewpoint of technological availability and payback period, the fuel conversion and waste heat recovery have an advantage in the short term with a possibility to reduce 160,000 $tCO_2-eq$. In the mid term, the thermal technologies in steel and iron industry have the potential to cut 229,000 $tCO_2-eq$, while the electrical technologies have the potential of 125,000 $tCO_2-eq$ reduction. The gap between the target GHG mitigation and potential reduction using the short and mid term technologies is about 38,000 $tCO_2-eq$, which should be compensated by the fundamental process innovation and the implementation of the most cutting-edge technologies including renewable energy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.1
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• pp.49-57
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• 2002

The possibility of a transmission noise reduction of piezoelectric smart panels using piezoelectric shunt damping is experimentally studied. Piezoelectric smart panel is basically a plate structure on which piezoelectric patch with shunt circuits is mounted and sound absorbing materials are bonded on the surface of the structure. Sound absorbing materials can absorb the sound transmitted at mid frequency region effectively while the use of piezoelectric shunt damping can reduce the transmission at resonance frequencies of the panel structure. To be able to reduce the sound transmission at low panel resonances, piezoelectric damping using the measured electrical impedance model is adopted. Resonant shunt circuit for piezoelectric shunt damping is composed of register and inductor in series, and they are determined by maximizing the dissipated energy throughout the circuit. The transmitted noise reduction performance of smart panels is investigated using an acoustic tunnel. The tunnel is a tube with square crosses section and a loud-speaker is mounted at one side of the tube as a sound source. Panels are mounted in the middle of the tunnel and the transmitted sound pressure across panels is measured. Noise reduction performance of a smart panels possessing absorbing material and/or air gap shows a good result at mid frequency region but little effect in the resonance frequency. By enabling the piezoelectric shunt damping, noise reduction of 10dB, 8dB is achieved at the resonance frequencise as well. Piezoelectric smart panels incorporating passive method and piezoelectric shunt damping are a promising technology for noise reduction in a broadband frequency.

• Journal of Climate Change Research
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• v.6 no.3
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• pp.233-241
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• 2015

In 2014, the United Nations Framework Convention on Climate Change (UNFCCC) agreed to submit the Intended Nationality Determined Contributions (INDCs) at the conference of parties held in Lima, Peru. Then, the South Korean government submitted the INDCs including GHGs reduction target and reduction potential on July, 2015. The goal of this study is to predict GHGs emission and to analyze reduction potential in agricultural sector of Korea. Activity data to estimate GHGs emission was forecast by Korea Agricultural Simulation Model (KASMO) of Korea Rural Economic Institute and estimate methodology was taken by the IPCC and guideline for MRV (Measurement, Reporting and Verification) of national greenhouse gases statistics of Korea. The predicted GHGs emission of agricultural sectors from 2021 to 2030 tended to decrease due to decline in crop production and its gap was less after 2025. Increasing livestock numbers such as sheep, horses, swine, and ducks did not show signigicant impact the total GHGs emission. On a analysis of the reduction potential, GHGs emission was expected to reduce $253Gg\;CO_{2-eq}$. by 2030 with increase of mid-season water drainage area up to 95% of total rice cultivation area. The GHGs reduction potential with intermittent drainage technology applied to 10% of the tatal paddy field area, mid-drainage and no organic matter would be $92Gg\;CO_{2-eq}$. by 2030.

• Journal of the Korean Society of Costume
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• v.65 no.3
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• pp.76-90
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• 2015

This is a basic study of the two remaining armors (artifacts number K2366, K2368) from the late Joseon dynasty that is part of the Korean costume collection, which is preserved in the Mission Museum of Saint Ottilien in Germany. The armor No. 1 (artifacts number K2366) is a coat-styled armor with brass studs. It has a U-shaped neckline with the non-overlapping collars and sleeve straight-lined inseam. The armor No. 1 has the Mu to the sides and is not back slit. Both its inner and outer material are padded with cotton. Leather mails are attached on the inner lining, and studs are attached on the outer lining to match the leather mails. For this reason, the armor No. 1 can be named MyeonPiGab (brass studded armor consisting of a cotton coat with internal leather mails). The outer material is faded to have the natural white, or antique white look and the patterns on it are indigo blue. The inner material is blue, but the original color is unknown since it is faded. The lotus blossoms and vine patterns are dyed on the surface of the outer material and a name is written on the inner material. The armor No. 1 was worn between the late 17th century and the 19th century. It is estimated that it was worn by military officers who were above the mid-rank in the end of the Joseon dynasty. The armor No. 2 (artifacts number K2368) is a coat-styled armor with brass studs and a low-cut U-shaped neckline. The armor No. 2 has a slit on the left armpit and a string around it. Studs are evenly attached on the armor. The iron mails are attached to the left chest area on its inner lining. It seems that it was designed with both formality and functionality in mind. The outer material is red flannel, the inner material is blue satin and the pads are cheesecloth. The side of its collars, cuffs, front lines, sidelines, back slit, and bottom lines are trimmed with fur. There are armors called "JeonCheolGap (brass studded armor consisting of a felt coat with internal iron mails)," which is similar to the armor No. 2, however, the similarities are limited because they are not made of the same material nor do they follow the same principle of nomenclature.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.305-305
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• 2011

Type-II 반도체 나노 구조는 그것의 band alignment 특성으로 인해 광학 소자에 다양한 응용성을 가진다. 특히, 대표적인 Type-II 반도체 나노 구조인 InSb/InAs 양자점의 경우, 약 3~5 ${\mu}m$의 mid-infrared 영역의 spectral range를 가지므로, 장파장을 요하는 소자에 유용하게 적용될 수 있다. 또한, Type-II 반도체 나노 구조의 밴드 구조를 staggered gap 혹은 broken gap 구조로 조절함으로써 infrared 영역 광소자의 전자 구조를 유용하게 바꾸어 적용할 수 있다. 최근, GaSb wafer 위에 InSb/InAsSb 양자점을 이용하여 cutoff wavelength를 6 ${\mu}m$까지 연장한 IR photodetector의 연구도 보고되고 있다. 하지만, GaSb wafer의 경우 그것의 비용 문제로 인해 산업적 적용이 쉽지 않다는 문제가 있다. 이러한 문제를 해결하기 위해 GaAs wafer와 같은 비용 효율이 높은 wafer를 사용한 연구가 필요할 것이다. 본 연구에서는 Molecular Beam Epitaxy(MBE)를 이용하여 undoped InAs wafer 와 semi-insulating GaAs wafer 상에 InSb 양자 구조를 형성한 결과를 보고한다. InSb 양자 구조는 20층 이상의 다층으로 형성되었고, 두 가지 경우 모두 400${\AA}$ spacer를 사용하였다. 단, InAs wafer 위에 형성한 InSb 양자 구조의 경우 InAs spacer를, GaAs wafer 위에 형성한 양자 구조의 경우 InAsSb spacer를 사용하였다. GaAs wafer 위에 양자 구조를 형성한 경우, InSb 물질과의 큰 lattice mismatch 차이 완화 뿐 아니라, type-II 밴드 구조 형성을 위해 1 ${\mu}m$ AlSb 층과 1 ${\mu}m$ InAsSb 층을 GaAs wafer 위에 미리 형성해 주었다. 양자 구조 형성 방법도 두 종류 wafer 상에서 다르게 적용되었다. InAs wafer 상에는 주로 일반적인 S-K 형성 방식이 적용된 것에 반해, GaAs wafer 상에는 migration enhanced 방식에 의해 양자 구조가 형성되었다. 이처럼 각 웨이퍼에 대해 다른 성장 방식이 적용된 이유는 InAsSb matrix와 InSb 물질 간의 lattice mismatch 차이가 6%를 넘지 못하여 InAs matrix에 비해 원하는 양자 구조 형성이 쉽지 않기 때문이다. 두 가지 경우에 대해 AFM과 TEM 측정으로 그 구조적 특성이 관찰되었다. 또한 infrared 영역의 소자 적용 가능성을 보기 위해 광학적 특성 측정이 요구된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.3
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• pp.144-150
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• 2016

Objectives: We compared the transbuccal and transoral approaches in the management of mandibular angle fractures. Materials and Methods: Sixty patients with mandibular angle fractures were randomly divided into two equal groups (A, transoral approach; group B, transbuccal approach) who received fracture reduction using a single 2.5 mm 4 holed miniplate with a bar using either of the two approaches. Intraoperatively, the surgical time and the ease of surgical assess for fixation were noted. Patients were followed at 1 week, 3 months, and 6 months postoperatively and evaluated clinically for post-surgical complications like scarring, infection, postoperative occlusal discrepancy, malunion, and non-union. Radiographically, the interpretation of fracture reduction was also performed by studying the fracture gap following reduction using orthopantomogram tracing. The data was tabulated and subjected to statistical analysis. A P -value less than 0.05 was considered significant. Results: No significant difference was seen between the two groups for variables like surgical time and ease of fixation. Radiographic interpretation of fracture reduction revealed statistical significance for group B from points B to D as compared to group A. No cases of malunion/non-union were noted. A single case of hypertrophic scar formation was noted in group B at 6 months postsurgery. Infection was noted in 2 patients in group B compared to 6 patients in group A. There was significantly more occlusal discrepancy in group A compared to group B at 1 week postoperatively, but no long standing discrepancy was noted in either group at the 6 months follow-up. Conclusion: The transbuccal approach was superior to the transoral approach with regard to radiographic reduction of the fracture gap, inconspicuous external scarring, and fewer postoperative complications. We preferred the transbuccal approach due to ease of use, minimal requirement for plate bending, and facilitation of plate placement in the neutral mid-point area of the mandible.

• The Southeast Asian review
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• v.19 no.2
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• pp.1-56
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• 2009

It is generally acknowledged that Philippines politics has achieved a basic soil for democracy at the macro-level by the two incidents of 'People Power' (1986 & 2001). However, in spite of such an achievement, Philippine politics at the micro-level, does not enjoy the same reputation. Institutionalized 'Bossism' or 'patron/clientelism' political culture has been attributed to make such a gap. This paper aims to bridge the gap by a longitudinal observation on local politics of a particular province in the Philippines. Surigao del Norte is the province picked up for the study. The reason why this particular province attracts special concerns is that there appears to come a very dynamic local politics, led by an indigenous Christian organization, the PBMA (Philippines Benevolent Missionary Association), which was founded in the mid 1960s. With the coming of the organization in the province, the political power of the traditional families has been narrowed. On the other hand, new families, not only the leader family of the PBMA but also the family allied with the PBMA, has expanded political influence. Following steps are adopted to understand the meaning of such a change. First, institutional frame of Philippine politics and elections will be reviewed. Second, demographic changes will be investigated on Surigao del Norte province to find out how popular the PBMA organization is among the people. Third, local election outcomes will be examined to describe the changing nature of political landscape of the province. This will reveal how the relationship between the old and new families has been developed in the province. Lastly, based on the facts discovered by a longitudinal observation, an attempt to evaluate theories on Philippines politics will be made Conclusions are as follows. To understand the dynamics of Philippine politics, 'expectations from the below,' or, 'passions of the people,' suggested by Ileto, needs more attention. Furthermore, 'mutual accommodation' between domination and resistance, coined by Abinales, also demands more appreciation. The case of local politics in the Surigao del Norte, with the coming of the PBMA, is sure to show a concrete example of changing politics in the 'changeless land.'

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3797-3803
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• 2009

Innovative capacities and performance are essential for the growth of the IT industry and the development of the Korean economy. Global R&D centers are important sources of innovation in the IT industry. In order to identify the structure of the innovation environment of global R&D centers in IT industry, we conducted a field survey of 50 global R&D centers and 50 global R&D policy experts in IT industry. According to the empirical results obtained using the Linear Structure Model, it is suggested that, first, with regard to a short-term IT global policy, the direction of the Korean government's policy should act as a trigger to connect the research domain and the market domain; second, the government policy should act as a facilitator to connect the development domain and the research domain in the mid-term period; and, finally, the government's R&D policy should serve as a disseminator to connect technological capability and the market space domain in the long-term perspective. For an effective way of internationalizing innovation, IT policy planners should regard global IT R&D centers as the important components of national innovation system and encourage the effective involvements by them in the process of IT industrial innovation.