• Korean Journal of Computational Design and Engineering
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• v.7 no.2
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• pp.131-139
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• 2002

Custom-tailored products always vary their sizes and shapes to satisfy the customers' tastes and requirements but they have to be fabricated as fast as possible when ordered. One way to solve this problem is to prepare several representative products in advance and each custom-tailored product is generated by machining the closest representative product. To realize this approach, it would be necessary to be able to group the products into several groups each of which has a representative product. Once the similar products are identified to be grouped, the representative shape can be generated such that all the products in the group can be made by machining the representative product. The custom-tailored products considered in this work have similar shapes but different sizes. Since these products have free surfaces, that are hard to be compared, their convex hulls are used for the grouping. Among all the products to be grouped, one product is chosen as a base shape. The shape and overall similarity values between the base shape and the remaining shapes are calculated as their convex hulls are rotated virtually. By calculating these similarity values at each rotation, the optimal alignment of the reference shape with respect to the base shape is determined. Overall similarity value at this optimal alignment is used as a measure for grouping. A prototype system based on the proposed methodology has been implemented and used to group the shoe-lasts for custom-tailored shoes.

• Journal of Welding and Joining
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• v.22 no.3
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• pp.69-76
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• 2004

Effects of friction stir welding parameters such as tool rotation speed and welding speed on the joints properties of 5052 Al alloys were studied in this study. A wide range of friction stir welding conditions could be applied to join 5052 AA alloy without defects in the weld zone except for certain welding conditions with a lower heat input. Microstructures near the weld zone showed general weld structures such as stir zone (SZ), thermo-mechanically affected zone (TMAZ) and heat affected zone (HAZ). Each zone showed the dynamically recrystallized grain, transient grain and structure similar to base metal's, respectively. Hardness distribution near the weld zone represented a similar value of the base metal under wide welding conditions. However, in case of 800 rpm of tool rotation speed, hardness of the stir zone had a higher value due to the fine grain with lots of dislocation tangle, a higher angle grain boundary and some of Al3Fe particles. Except joints with weld defects, tensile strength and elongation of the joints had values similar to the base metal values and fracture always occurred in the regions approximately 5mm away from the weld center.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.8
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• pp.927-938
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• 2014

A number of crime and disease relief situation show a clear increasing trend in domestic and overseas country. In particular, we desperately need a fast location information sharing with high accuracy for dealing with this situation efficiently. In this paper, we propose a DGPS framework and performance evaluation based on Web service enable increase location accuracy using low-cost GPS or AGPS. The framework consists of mobile station to realize the final service by receiving the correction values that are created in the base station closest to the current position from DGPS server, base station system to transmit the correct values to DPGS server by installing at base point and DGPS framework working at DGPS server. Our framework is fundamentally designed to respond based on XML to service request. In addition, for performance evaluation, we make use of 3 sites of Level 2 city base-station among the base stations being operated in Suncheon-si. Through performance evaluation, we show that our framework outperforms about 10%~15% in terms of error improvement rate, compared with the existing schemes. And we have the advantage that various services can be expanded owing to receiving the correction values through mobile device such as, smart phone, smart pad, net-book by using XML based Web services.

• Journal of the Korean Society for Nondestructive Testing
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• v.2 no.2
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• pp.9-16
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• 1983

There are two weak points in a high pressure vessel, one is a corner, the other is a crack on the base. In order to evaluate safety of a department of a corner and a crack like a starfish on the base in a high pressure vessel (working pressure: $130kg/cm^{2}$), which was made by Marison's Process, we analyzed stress by strain gauge, measured thickness and hardness by ultrasonic testing, and were able to test pressure by water pressure from nondestructive testing. Also destructive testings were applied to measure thickness and to observe microstructure and chemical composition of a corner on the base. From the results of the experiment, values of experiment were satisfied with a condition of application. But, it is considered that a crack on the base is to be investigated with more by Fracture Mechanics.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.10a
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• pp.409-429
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• 2006

In designing rock-socketed drilled shaft, bearing capacity evaluation is very important because the maximum values of base and side resistance are not generally mobilized at the same value of displacement, FHWA and AASHTO code suggest different ultimate bearing capacity formular according to rock type and shaft settlement. In domestic code suggest base resistance and side resistance can be added on condition that after confirming the result of field load test with axial load transfer test. This paper shows that static load test and hi-directional load test result analysis of deep rock-socketed drilled shaft in three different sites. Load-settlement curve, t-z, and q-w curve in rock-socketed part were calculated and compared. t-z curve in weathered and soft rock showed no deflection softening behavior in pretty large strain (about 2-3% of diameter). Ultimate resistance could be the summation of side resistance and base resistance in rock-socketed drilled shaft in domestic sites.

• Imaging Science in Dentistry
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• v.45 no.1
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• pp.67-72
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• 2015

Arrested pneumatization of the sphenoid sinus is a developmental variant that is not always well recognized and is often confused with other pathologies associated with the skull base. This report describes the case of a patient referred for cone-beam computed tomography (CBCT) imaging for dental implant therapy. CBCT demonstrated a well-defined incidental lesion in the left sphenoid sinus with soft tissue-like density and sclerotic borders with internal curvilinear opacifications. The differential diagnoses included intraosseous lipoma, arrested pneumatization of the sphenoid sinus, chondrosarcoma, chondroid chordoma, and ossifying fibroma. The radiographic diagnosis of arrested pneumatization was based on the location of the lesion, its well-defined nature, the presence of internal opacifications, and lack of expansion. Gray-scale CBCT imaging of the area demonstrated values similar to fatty tissue. This case highlighted the fact that benign developmental variants associated with the skull base share similar radiographic features with more serious pathological entities.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.10 no.2
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• pp.80-85
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• 2011

In this paper, I propose flexible base point used for a BTC(Block Truncation Coding). Halftoning images are used for printer by reducing the number of pixel depth. During over 20 years, many researches have been studied to apply this techniques to image compression. BTC algorithms are the compression methods using digital halftoning technique about images. In the BTC algorithm, an image block is divided into higher and lower domain compared with the mean of block. then the MAX and MIN representative values are evaluated by calculating the mean of higher and lower domain respectively. At a result, an image block(for example 88 size) is compressed into 64bits pixel representation and 16 bits of the MAX and MIN. And they also have been tried to sustain the image quality high after compression. In this paper, I found that there is some marginal possibility to enhance the image quality by adjusting the base point(generally mean of block) of existing algorithms.

• Journal of Mechanical Science and Technology
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• v.15 no.10
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• pp.1423-1433
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• 2001

A flow modeling method has been developed to analyze the flow in the annular base (rear- facing surface) of a circular engine nacelle flying at subsonic speed but with a supersonic exhaust jet. Real values of exhaust gas properties and temperature at an altitude of 30, 000 feet are employed. Potential flows of the air and gas streams are computed for the flow past a separated wake. Then a viscous jet mixing is superimposed on this inviscid solution. Conserva- tion of mass, momentum and energy for the wake flow field is achieved by multiple iterations with modest computer requirements.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.545-555
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• 2014

To develop Korean-style cut noodles with enhanced protein and calcium levels, we manipulated the ratio of dried anchovy Engraulis japonicus soup base residue powder to wheat flour, using a response surface methodology based on trained panel trials to determine the optimum ratio. Texture analysis and nutritional evaluation were also performed on cut noodles containing dried anchovy soup base residue (CNAR). Higher umami taste and springiness, and lower fishy flavor were strongly correlated with overall acceptability. The optimal CNAR formulation consisted of wheat flour (96.02 g), anchovy residue powder (2.67 g), and water (50.64 mL). CNAR had lower gumminess and adhesiveness (P<0.001), but higher springiness, cohesiveness (P<0.001), and chewiness (P<0.05), than the control (original wheat flour cut noodles). The addition of anchovy soup base residue elevated protein, lipid, and ash levels relative to the control. Color values decreased with increasing residue powder content. In vitro protein and starch digestibility of CNAR were lower than in the control (P<0.001). CNAR yielded significantly higher total free amino acid content than the control (P<0.01), leading to CNAR's improved palatability. Dried anchovy soup base residue can be used in wheat flour cut noodles to improve nutrition, sensory acceptability, and profitability.

• Journal of Welding and Joining
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• v.18 no.3
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• pp.106-113
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• 2000

Single crystallization behavior ad high temperature tensile properties of TLP bonded joints of Ni-base single crystal superalloy, CMSX-2 were investigated using MBF-80 and F-24 insert metals. CMSX-2 was bonded at 1523~1548K for 1.5~1.8ks in vacuum. The (100) orientation of bonded specimen was aligned perpendicular to the joint interface. Crystallographic orientation analyzed points over the bonded region possessed the almost same orientation across the joint interface and misorientation $\Delta^{\theta}$ was negligibly small in as-bonded and post-bond heat-treated situations. It was confirmed that single crystallization could be readily achieved during TLP bonding. The tensile strengths of all joints at elevated temperatures were equal to or greater than those of base metal the range of testing temperature between 923K and 1173K. The elongation and reduction of area in values were almost the same as those of base metal. SEM observation of the fracture surfaces of joints after tensile test revealed that the fracture surface indicated the similar morphologies each other, and that the fracture of joints occurred in the base metal in any cases.