• Journal of the Korean Society of Visualization
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• v.11 no.1
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• pp.48-52
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• 2013

This paper presents experimental observation of asymmetric electrohydrodynamic flow generated around a pair of symmetric coplanar electrodes. Electrodes are attached on the bottom of the cavity containing a dielectric liquid, i.e., a mixture of dodecane and 0.5% wt Span80. In the first experiment, an AC voltage of 1500 V is applied with the frequency varying in the range 10~500 hz and the left electrode being grounded. The flow patterns show that the center line of vortices is unexpectedly tilted to the left side. If the right side electrode is grounded, the center line is tilted to the right side. The magnitude of the fluid velocity shows an irregular variation with the frequency in the range 10 Hz~100 Hz, beyond which it simply decays. In the second experiment, we applied fixed AC with 1000 V and 60 Hz superposed by DC voltage varying in the range -1000 V ~ +1000 V. The center line of the flow pattern is tilted to the right side with positive DC voltage and to the left side with negative DC. We have managed to show that the flow pattern can be symmetric with a suitable combination of DC and AC, e.g., DC 850 V plus AC 1000 V with the frequency 10 Hz.

• Journal of Power System Engineering
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• v.17 no.5
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• pp.121-127
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• 2013

In this paper, we propose a distance measurement system for automatic berthing control using a stereo camera mounted on a rotation control device, and a radial pattern target. Automatically controlling the position and attitude of a ship aims to prevent maritime accidents due to human error. Our goal is to measure the relative distance between a ship and an onshore or offshore target for berthing. Therefore, the distance should be continuously measured while tracking a fixed point on a target. To this end, we developed a stereo camerabased distance measurement system that satisfied these requirements. This paper describes the structure and principle of the measurement system. We validate the distance error for target incline due to the relative position and attitude between a camera and a target in miniature scale. In addition, the findings of an experiment in an outdoor environment demonstrate that the proposed measurement system has accuracy within 1 m at a range of 20-100 m which is the acceptable accuracy for automatic berthing.

• Journal of the Optical Society of Korea
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• v.18 no.5
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• pp.500-506
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• 2014

A new 3-D reconstruction algorithm for the human face is proposed using the derivative Moir$\acute{e}$ topography which ensures fast and robust reconstruction even for rough surfaces. The Moir$\acute{e}$ interference fringe pattern is initially obtained through the projection Moir$\acute{e}$ topography based on phase shifting, and then differentiated to provide a full unwrapped phase map for a human face. $2{\pi}$ ambiguity, which has been a chronically unsolved problem with Moir$\acute{e}$ topography, is successfully surmounted by differentiating the Moir$\acute{e}$ fringe patterns both in x- and y-directions when the object is located in the x-y plane. A real human face is used for verifying the proposed derivative Moir$\acute{e}$ topography. A human face of 4 different phase-shifted images taken in the fixed plane is almost fully reconstructed in 3-D format in 0.1 mm lateral resolution.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.3
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• pp.219-231
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• 2009

Numerical simulations have been carried out for a 138K LNG Carrier (KLNG) model ship with free surface, using WAVIS 2.0 and Fluent 6.3.26 with various $y^+$ values and different grid densities. Level-set method for free surface capturing was adopted in WAVIS, while VOF has been used in Fluent. The calculated results were compared with the experiment data. Resistance coefficient, wave pattern, wave profile along the hull surface, axial velocity contours and transverse vectors had been analyzed. When the first $y^+$ value was fixed at 60, the simulation results from both WAVIS and Fluent were improved as the number of grids increased. The convergence time of WAVIS was much shorter than that of Fluent. Furthermore, WAVIS predicted the velocity field and the wave profile along the hull surface better than Fluent. However, Fluent gave better wave patterns.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.2
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• pp.187-190
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• 2001

Inheritance pattern of resistance to Bombyx mori nuclear polyhedrosis virus (BmNPV) was studied in an Indian silkworm stock TX by single back-cross test method. The resistant parent ［TX］, susceptible parent ［HM］, their Fl, F2, and Fl progeny back-crossed to TX [BC(R)] and HM [BC(S)] were inoculated per os with a fixed concentration of BmNPV($0.5{\times}10^{th} PIB/ml$) on the first day of second stadium. The cumulative mortality was recorded until day $10^{\times}$ post-inoculation. The results show that the resistance to BmNPV in TX fellow mono Mendelian inheritance pattern. The resistance dominated over the susceptibility at Fl. At F2, the resistant and susceptible offspring segregated in 3:1 ratio whereas at BC(S), the resistant and susceptible offspring segregated in 1:1 ratio. The response of BC(R) was more or less like the resistant parent TX which confirms the involvement of a major dominant gene conferring resistance to BmNPV in TX. The possible mechanism of inheritance of resistance in TX is discussed.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.6
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• pp.28-34
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• 2004

The old technique of sandblasting which has been used for decoration of glass surface has recently been developed into a powder blasting technique for brittle materials such as glass, silicon and ceramics, capable of producing micro structures larger than 100${\mu}{\textrm}{m}$. In this study, we introduced oblique powder blasting, and investigated the effect of the impacting angle of particles, the scanning times and the stand-off distance on the surface roughness and the weight-loss rate of samples with no mask, and the wall profile and overetching of samples with different mask pattern in powder blasting of soda-lime glass. The varying parameters were the different impact angles between 50$^{\circ}$ and 90$^{\circ}$, scanning times of nozzle up to 40 and the stand-off distances 70mm and 100mm. The widths of mask pattern were 0.2mm, 0.5mm and 1mm. The powder was alumina sharp particles, WA #600. The mass flow rate of powder during the erosion test was fixed constant at 175g/min and the blasting pressure of powder at 0.2Mpa.

• Fisheries and Aquatic Sciences
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• v.22 no.8
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• pp.18.1-18.5
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• 2019

The development of sex-specific genetic assays in a species provides both a method for identifying the system of sex determination and a valuable tool to address questions of conservation and management importance. In this study, we focused on the identification of single nucleotide polymorphisms (SNPs) that differentiate genetic sex in burbot Lota lota. Burbot are the only true freshwater representative of the cod family and a species of conservation and management importance throughout Eurasia and North America. To identify sex-specific SNPs, we utilized restriction site-associated DNA sequencing (RADseq) to interrogate thousands of SNPs in burbot samples of known phenotypic sex. We discovered 170,569 biallelic SNPs, none of which fit the pattern expected under female heterogamety. However, we identified 22 SNPs that fit the pattern expected under male heterogamety (males heterozygous XY, females fixed XX) and, from these, developed two genetic assays that robustly (~ 97% genotyping success) and accurately (> 99% correct) sexed burbot samples. These sex-specific genetic assays will benefit growing conservation aquaculture programs for this species and allow future assessments of sex-specific migration, growth, and mortality.

• East Asian Journal of Business Economics (EAJBE)
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• v.10 no.4
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• pp.75-90
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• 2022

Purpose - This study aims to study the activation pattern of declining industries by applying the Gompertz growth model using available resources based on the theory of industrial life cycle, classifying declining industries among Korean manufacturing industries, and identifying resource input characteristics. Research design and methodology - This study was conducted by combining the Gompertz growth model that predicts the limit of output based on available resources under the industrial life cycle theory. Using Gompertz model, this study analyzed the life cycle of 39 Korean manufacturing industries from the perspective of domestic production, number of employees, and fixed assets Results - According to a life cycle analysis of 39 manufacturing industries in Korea, the computer, textile, and shoe industries were classified as declining industries. Among them, research on resource input characteristics on the shoe industry showed that domestic production and the number of employees decreased, while the proportion of domestic R&D personnel and the number of research departments gradually increased. Conclusion - Among the declining industries in Korea, the shoe industry is considered to revitalize the industry, that is, to extend the life of the declining industry by offshoring its production site and improving constitution with a "R&D center for global" support.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.4
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• pp.769-781
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• 1997

The purpose of this research is to show how to use the patternist's CAD system in order to make design patterns efficiantly. Using the PAD System Technologies company's PAD System Module, which is very officiant in designing patterns, the basic pattern or design pattern can be designed and applyed to the Sample Module, thus, then it could manufacture, retouch or choose a model, making it posible to go to the next level which is seam patterns for industrial use. By understanding the change of the design that is chosen through the design pattern making and Sample Module process', this study is presentated a plan on how to utilize the patternist's working adaption ability by the CAD system, and also considered the problems in using it. Ability of Design Confrontation of CAD System: 1) The result of an operation can be saved and retouched. On a saved list the patterns can be chosen and changed, thus, making it posible to complete a design very quickly. 2) When sewing every designed pattern in Sample Module, the model can be operated merely by selecting each sewing position, thus creating the same effect of a designer's muslin sample process in a much lesser time. Point at issue in the utilization CAD system: 1) When combining two darts into one place the amounts of darts that are already these have to be erasers, and then, the two darts points are moved that place, thus, containing them, which is very conplicated. 2) When making a gathering, because system can only be recognized in a opend line, the pattern should be separated in order to put a gathering inside a pattern. 3) In order to readjust the amounte of dart. The dart is erased first and then made new dart again. 4) When making tucks in a Sample Module, the form that gets narrow towards the pivot point can not be recognized so the sewing lines of the tucks is adjusted into parallel lines. 5) The Sample Module 3D operation can not attach the bodice to the shirts, instead they become fixed into each other. In the case of shoulder line tucks the amounts of pleats can not be expanded draperary naturally, thus, making it hard to showing the silhouette accurately. If these problems are solved, especially if the silhouette of a model can be created to have natural drapery in the 3D Module, models can be shown on the screen in possible to compare and examine even a change of a detail, by designing this 3D Module Production sample process will be more effective, thus, making the CAD system more useful in sewing design process.

• Journal of Internet Computing and Services
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• v.10 no.2
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• pp.1-13
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• 2009

Intrusion detection is a process that identifies the attacks and responds to the malicious intrusion actions for the protection of the computer and the network resources. Due to the fast development of the Internet, the types of intrusions become more complex recently and need immediate and correct responses because the frequent occurrences of a new intrusion type rise rapidly. Therefore, to solve these problems of the intrusion detection systems, we propose a sequential pattern miner for analysis of the alert data in order to support intelligent and automatic detection of the intrusion. Sequential pattern mining is one of the methods to find the patterns among the extracted items that are frequent in the fixed sequences. We apply the prefixSpan algorithm to find out the alert sequences. This method can be used to predict the actions of the sequential patterns and to create the rules of the intrusions. In this paper, we propose an extended prefixSpan algorithm which is designed to consider the specific characteristics of the alert data. The extended sequential pattern miner will be used as a part of alert data analyzer of intrusion detection systems. By using the created rules from the sequential pattern miner, the HA(high-level alert analyzer) of PEP(policy enforcement point), usually called IDS, performs the prediction of the sequence behaviors and changing patterns that were not visibly checked.