• Journal of the Society of Naval Architects of Korea
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• v.31 no.1
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• pp.22-31
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• 1994

Fish aggregating devices(FAD) or artificial fish reefs deployed in the ocean space have been developed in various forms. The objective of FAD is to aggregate, cultivate and proliferate aquatic resources by making changes in ocean flows around it. developing spawning grounds, improving feeding areas and protecting larvae and juveniles. Most floating fish aggregating devices(FFAD) are in the form of surface buoys or subsurface buoys with a single point mooring system(SPMS). The mooring line of SPMS for the secure positions of FFAD is expected to keep great stresses as a result of the harsh ocean environment. Laboratory static tests on synthetic fiber ropes used for the SPMS were run. The Nylon wet rope specimen tests under increasing-and-decreasing loads showed about 20% strength drop. Also the logarithmic creep-tie behavior of fiber ropes was observed in the constant load test and compared with Flessner's formula.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.3
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• pp.62-73
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• 2001

The interest in evaluation of structural intensity arises for practical reasons, because net energy flow distribution offers information of energy transmission path, positions of sources, and sinks of vibration energy. In this paper, structural intensity analysis of local ship structures using finite element method(FEM) is carried out. The purpose of this analysis is to evaluate the relative accuracy according to mesh fineness. The structural intensity of unstiffened and stiffened plates varying their mesh fineness is analyzed and the results are compared with those obtained by the assumed mode method. As results, the proper mesh size in qualitative/quantitative structural intensity analysis of plate structures is proposed. In addition, the propagation phenomenon of vibration energy is investigated for the thickness-varying flat plate, L-type plate, and box-girder structures.

• Journal of the Korean Solar Energy Society
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• v.38 no.5
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• pp.11-25
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• 2018

The Ln-least method is commonly used to estimate the Weibull parameters from the observed wind speed data. In previous studies, the bin method has been used to calculate the cumulative frequency distribution for the Ln-least method. The purpose of this study is to obtain better performance in the Ln-least method by applying probability plotting position(PPP) instead of the bin method. Two types of the wind speed data were used for the analysis. One was the observed wind speed data taken from three sites with different topographical conditions. The other was the virtual wind speed data which were statistically generated by a random variable with known Weibull parameters. Also, ten types of PPP formulas were applied which were Hazen, California, Weibull, Blom, Gringorten, Chegodayev, Cunnane, Tukey, Beard and Median. In addition, in order to suggest the most suitable PPP formula for estimating Weibull parameters, two accuracy tests, the root mean square error(RMSE) and $R^2$ tests, were performed. As a result, all of PPPs showed better performances than the bin method and the best PPP was the Hazen formula. In the RMSE test, compared with the bin method, the Hazen formula increased estimation performance by 38.2% for the observed wind speed data and by 37.0% for the virtual wind speed data. For the $R^2$ test, the Hazen formula improved the performance by 1.2% and 2.7%, respectively. In addition, the performance of the PPP depended on the frequency of low wind speeds and wind speed variability.

• STI Policy Review
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• v.5 no.2
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• pp.65-95
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• 2014

The recent decades have seen a growing rate of international cooperation in science, technology, and innovation (STI) including in the field of green technologies. However, current approaches to national systems of innovation (NSI) have not kept up with this development. International aspects are rather treated as external conditions within which policymakers operate and respond but not influence. This paper tackles this problem by applying a refined NSI concept that includes an international dimension and complements past frameworks by focusing on those Korean government policies, actors, and activities relevant for the internationalization of STI. Austria and Korea have both formulated differing strategies to acquire international leading positions in the field of innovation and the development of green technologies. In the first step, the paper assesses Korea's international activities within the field of green technologies that transcend national boundaries and establish international connections. The government has still a strong influence on selecting technology areas for strategic funding but our findings show that international STI actors have difficulties in identifying the appropriate point of contact to initiate cooperation or apply for related funding. Second, an external perspective on Korea's international collaborations in the field of green technologies is offered. Austria has tentatively identified the East Asian country as a second-priority cooperation partner for its future STI internationalization activities. Interviews with Austrian stakeholders in the field of green technologies indicate a high interest in cooperation with Korea that is facilitated by a similar business culture based on personal networks. Moreover, researchers and policymakers referred to a shared need of small countries for intelligent decision-making processes regarding potential cooperation partners abroad. However, in order to enhance awareness, visibility and demand for Korean STI cooperation in European countries, more long-term funding programs featuring a more permanent point of contact should be introduced.

• Safety and Health at Work
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• v.2 no.4
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• pp.348-354
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• 2011

Objectives: This cross-sectional study was performed in the Dental School of Prince of Songkla University to ascertain noise exposure of dentists, dental assistants, and laboratory technicians. A noise spectral analysis was taken to illustrate the spectra of dental devices. Methods: A noise evaluation was performed to measure the noise level at dental clinics and one dental laboratory from May to December 2010. Noise spectral data of dental devices were taken during dental practices at the dental services clinic and at the dental laboratory. A noise dosimeter was set following the Occupational Safety and Health Administration criteria and then attached to the subjects' collar to record personal noise dose exposure during working periods. Results: The peaks of the noise spectrum of dental instruments were at 1,000, 4,000, and 8,000 Hz which depended on the type of instrument. The differences in working areas and job positions had an influence on the level of noise exposure (p < 0.01). Noise measurement in the personal hearing zone found that the laboratory technicians were exposed to the highest impulsive noise levels (137.1 dBC). The dentists and dental assistants who worked at a pedodontic clinic had the highest percent noise dose (4.60 ${\pm}$ 3.59%). In the working areas, the 8-hour time-weighted average of noise levels ranged between 49.7-58.1 dBA while the noisiest working area was the dental laboratory. Conclusion: Dental personnel are exposed to noise intensities lower than occupational exposure limits. Therefore, these dental personnel may not experience a noise-induced hearing loss.

• Korean Journal of Optics and Photonics
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• v.14 no.6
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• pp.613-622
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• 2003

The multi-configurative microscopic system for inspecting the wire-bonding of reed frame is designed. Rays refracted by objective lens group which is composed of common lens group of x2 and x6 are splitted by beam-splitter, and Rays through the central region and the boundary region of the object imaged at x2 and x6 through imaging lens groups, respectively. The depth of wire structure on the reed frame has about $\pm$3 mm, in order to observe by uniform magnification without the dependency on the variation of objective distance generated by the depth of wire structure on the reed frame, imaging lens groups should be moved on nonlinear locus like mechanically compensated zoom lenses. The nonlinear equations for zoom locus are derived by using the Gaussian bracket. Refraction powers and positions of each groups are numerically determined by solving the equations, and initial design data for each groups is obtained by using Seidel third order aberration theory. The optimization technique is finally utilized to obtain this microscopic system.

• Korean Journal of Optics and Photonics
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• v.12 no.2
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• pp.103-108
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• 2001

In this paper, we designed and made the scanned point detecting system for 3-dimensional measurement of the light emitted from plasma display panel (PDP) , and we measured and analyzed 3-dimensional light emitted from a real PDP by using this scanned point detecting system. The scanned point detecting system has a point detector with a pinhole. The light emitted from the source at the in-focus position can pass through the pinhole and be collected by detector. The light from other sources at outof-focus positions is focused at points in front of or behind the pinhole, and thus it is intercepted by the pinhole. Therefore, we can detect light information from a particular point of a PDP cell of 3-dimensional structure. We know the electric field distribution inside the PDP cell from the 3-dimensionallight intensity distribution measured by using the scanned point detecting system. As the Z axial measurement increases, the intensity of light detected increases and intensity of light detected on the inside edge of the ITa electrode is larger than outside edge of the ITa eletrode and gap of the ITa electrodes. Also, as the measurement point moves from one barrier rib to another, the detected light is weaker near to the barrier ribs than at the center between the barrier ribs. The emitted light is concentrated at the center between barrier ribs. ribs.

• Korean Journal of Optics and Photonics
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• v.14 no.6
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• pp.594-599
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• 2003

By using the spectroscopic ellipsometry, we have measured and analyzed the optical characteristics of P $r^3$$^{+}$-doped selenide glasses of Ge-Sb-Se system, a strong candidate material for U band fiber amplifiers. The ellipsometric spectra measured in the transparent wavelengths range of the material were all fitted to a model consisting of ambient/roughness/thin fil $m_strate structures to obtain simultaneously the optical properties such as refractive index, in terms of Sellmeier parameters and film structure of P $r^3$$^{+}$-doped selenide glasses. Repeated measurements on different positions in both polished faces rendered to verify positional dependence of measured spectre-ellipsometric data. Hence, the model made possible the analysis of the optical characteristics of the glasses. Even though surface roughness was mainly responsible for the position dependencies, the averaged refractive indexes were as precise as to reflect the minute compositional change tantamount to 1 mol%. The measured refractive indexes are useful for design of core and clad compositions of single-mode selenide optical fibers.

• Advances in concrete construction
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• v.5 no.5
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• pp.451-468
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• 2017

The problem of reducing the self-weight of reinforced concrete structures is very important issue. There are two approaches which may be used to reduced member weight. The first is tackled through reducing the cross sectional area by using voids and the second through using light weight materials. Reducing the weight of slabs is very important as it constitutes the effective portion of dead loads in the structural building. Eleven slab specimens was casted in this research. The slabs are made one way though using two simple supports. The tested specimens comprised three reference solid slabs and eight styropor block slabs having (23% and 29%) reduction in weight. The voids in slabs were made using styropor at the ineffective concrete zones in resisting the tensile stresses. All slab specimens have the dimensions ($1100{\times}600{\times}120mm$) except one solid specimens has depth 85 mm (to give reduction in weight of 29% which is equal to the styropor block slab reduction). Two loading positions or cases (A and B) (as two-line monotonic loads) with shear span to effective depth ratio of (a/d=3, 2) respectively, were used to trace the structural behavior of styropor block slab. The best results are obtained for styropor block slab strengthened by minimum shear reinforcement with weight reduction of (29%). The increase in the strength capacity was (8.6% and 5.7%) compared to the solid slabs under loading cases A and B respectively. Despite the appearance of cracks in styropor block slab with loads lesser than those in the solid slab, the development and width of cracks in styropor block slab is significantly restricted as a result of presence a mesh of reinforcement in upper concrete portion.

• Journal of the Korea Society of Computer and Information
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• v.26 no.10
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• pp.9-17
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• 2021

Humans are social animals that have gained information or social interaction through dialogue. In conversation, the mood of the word can change depending on the sensibility of one person to another. Relationships between characters in films are essential for understanding stories and lines between characters, but methods to extract this information from films have not been investigated. Therefore, we need a model that automatically analyzes the relationship aspects in the movie. In this paper, we propose a method to analyze the relationship between characters in the movie by utilizing deep learning techniques to measure the emotion of each character pair. The proposed method first extracts main characters from the movie script and finds the dialogue between the main characters. Then, to analyze the relationship between the main characters, it performs a sentiment analysis, weights them according to the positions of the metabolites in the entire time intervals and gathers their scores. Experimental results with real data sets demonstrate that the proposed scheme is able to effectively measure the emotional relationship between the main characters.