• Journal of the Microelectronics and Packaging Society
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• v.26 no.4
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• pp.149-156
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• 2019

A stretchable thermoelectric module consisting of 5 pairs of Bi₂Te₃-based hot-pressed p-n thermoelectric legs was processed by filling the module inside with polydimethylsiloxane (PDMS) and removing the top and bottom substrates. Its stretchable characteristics and power generation properties were measured. The integrity of the module was kept well even after 10 strain cycles ranging from 0 to 0.1. With increasing the tensile strain to 0.2, the module circuitry became open because of joint failure between Cu electrodes and thermoelectric legs. The stretchable thermoelectric module exhibited an open circuit voltage of 4.6 mV with a temperature difference of 2.2K across both ends of thermoelectric legs, and changes in its open circuit voltage were below 5% for tensile strains of 0~0.1. Being elongated for a strain of 0.1, it exhibited the maximum output power of 18.5 ㎼ with the temperature difference of 2.2K across its both ends.

• Clinics in Shoulder and Elbow
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• v.26 no.3
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• pp.287-295
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• 2023

Background: Posterolateral rotatory instability (PLRI) is a common mechanism of recurrent elbow instability. While the essential lesion is a deficiency in the lateral ulnar collateral ligament (LUCL), there are often associated concomitant bony lesions, such as an Osborne-Cotterill lesions (posterior capitellar fractures) and marginal radial head fractures, that compromise stability. Currently, there is no standard treatment for posterior capitellar deficiency associated with recurrent PLRI. Methods: We conducted a retrospective review of five patients with recurrent PLRI of the elbow associated with a posterior capitellar impaction fracture engaging with the radial head during normal range of motion. The patients were treated surgically with LUCL reconstruction or repair and off-label reconstruction of the capitellar joint surface using a small metal prosthesis designed for metatarsal head resurfacing (HemiCAP toe classic). Results: Five patients (three adolescent males, two adult females) were treated between 2007 and 2018. At a median follow-up of 5 years, all patients had complete relief of their symptomatic instability. No patients had pain at rest, but two patients had mild pain (visual analog scale 1-3) during physical activity. Three patients rated their elbow as normal, one as almost normal, and one as greatly improved. On short-term radiographic follow-up there were no signs of implant loosening. None of the patients needed reoperation. Conclusions: Recurrent PLRI of the elbow associated with an engaging posterior capitellar lesion can be treated successfully by LUCL reconstruction and repair and filling of the capitellar defect with a metal prosthesis. This treatment option has excellent clinical results in the short-medium term. Level of evidence: IV.

• Journal of the Korean Wood Science and Technology
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• v.36 no.6
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• pp.77-87
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• 2008

Wooden model erosion control dam was made with pitch pine, of which the strength properties was evaluated. Wooden model erosion control dam was made with diameter 90 mm of pitch pine round posts treated with CUAZ-2 (Copper Azole), changing joint in three different types. In each type, erosion control dam was made in nine floor (cross-bar of five floors and vertical-bar of four floors), of which the hight was 790 mm. And then strength properties were investigated through horizontal loading test and impact strength test, and the deformation of structure through image processing (AICON 3D DPA-PRO system). In horizontal loading test of wooden model erosion control dam using round post of diameter 90 mm, whether there was stone or not did not affect strength much when using self drill screw, but strength was decreased by 23%. In monolithic type of erosion control dam using screw bar, strength was increased by 1.5 times and deformation was decreased when filling with stone. When reinforcing with screw bar that ring is connected to self drill screw, strength was increased by 4.8 times. In impact strength test of wooden model erosion control dam made with round post of diameter 90 mm, the erosion control dam connected with self drilling screw not filling with stone was totally destroyed by the 1st impact, and the erosion control dam using screw bar was ruptured at cross-bar at which 779 kgf of impact was loaded in the 1st impact. In the 2nd impact, the base parts were ruptured, and reaction force was decreased to 545 kgf. In the 3rd impact, whole base parts were destroyed, and reaction force was decreased to 263 kgf.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.6
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• pp.8-17
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• 2011

Recently, fusion camera systems that consist of depth sensors and color cameras have been widely developed with the advent of a new type of sensor, time-of-flight (TOF) depth sensor. The physical limitation of depth sensors usually generates low resolution images compared to corresponding color images. Therefore, the pre-processing module, such as camera calibration, three dimensional warping, and hole filling, is necessary to generate the high resolution depth map that is placed in the image plane of the color image. However, the result of the pre-processing step is usually inaccurate due to errors from the camera calibration and the depth measurement. Therefore, in this paper, we present a depth map upsampling method robust these errors. First, the confidence of the measured depth value is estimated by the interrelation between the color image and the pre-upsampled depth map. Then, the detailed depth map can be generated by the modified kernel regression method which exclude depth values having low confidence. Our proposed algorithm guarantees the high quality result in the presence of the camera calibration errors. Experimental comparison with other data fusion techniques shows the superiority of our proposed method.

• The Journal of Engineering Geology
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• v.25 no.1
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• pp.115-129
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• 2015

The cut-slope of a large-sectional tunnel portal is recognized as a potential area of weakness due to unstable stress distribution and possible permanent displacement. This paper presents a case study of a slope failure and remediation for a large-scale cut-slope at a tunnel portal. Extensive rock-slope brittle failure occurred along discontinuities in the rock mass after 46 mm of rainfall, which caused instability of the upper part of the cut-slope. Based on a geological survey and face mapping, the reason for failure is believed to be the presence of thin clay fill in discontinuities in the weathered rock mass and consequent saturationinduced joint weakening. The granite-gneiss rock mass has a high content of alkali-feldspar, indicating a vulnerability to weathering. Immediately before the slope failure, a sharp increase in displacement rate was indicated by settlement-time histories, and this observation can contribute to the safety management criteria for slope stability. In this case study, emergency remediation was performed to prevent further hazard and to facilitate reconstruction, and counterweight fill and concrete filling of voids were successfully applied. For ultimate remediation, the grid anchor-blocks were used for slope stabilization, and additional rock bolts and grouting were applied inside the tunnel. Limit-equilibrium slope stability analysis and analyses of strereographic projections confirmed the instability of the original slope and the effectiveness of reinforcing methods. After the application of reinforcing measures, instrumental monitoring indicated that the slope and the tunnel remained stable. This case study is expected to serve as a valuable reference for similar engineering cases of large-sectional slope stability.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.4
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• pp.758-770
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• 1996

Discectomy is the oldest and most commonly performed operation for the painful temporomandibular joint with internal derangement. It is the one operation for which there are longest follow-up study, with Eriksson, Silver, and Tolvanen et al reporting good results in patients about 30 years after discectomy. About 80% to 90% of patients clinically experience relief from pain and dysfunction after discectomy, and interestingly, the results may improve with time. However such as Myrhaug found headache and Poswillo supposed pain and limitation of movement as postoperative complications, even though this operation had the longest follow-up term, several aspects of discectomy remain unclear. The controversies to discectomy for TMJ with pain and dysfunction have laid emphasis only upon clinical results, and then the histomorphological study was planned to evaluate the morphologic change of TMJ after discectomy. To clarify the nature of the change through an observation on the morphologic changes of articular cartilage and subchondral bone of the condyle resulting from experimental unilateral discectomy in rabbit, the author excised the left articular discs of 12 male rabbits(control 4 rabbits), weighing about 3kg, and at 1, 3, 6, 9 weeks following surgery, harvested both(left surgical site and right nonsurgical sits) TMJ. The specimens were examined with light microscope after H-E and MT stain and the obtained results were as follows. 1. Histopathological features showed thickening of articular zone and active proliferation of fibrocartilaginous zone associated with slight proliferative zone in surgical site than control group. Also replacement of chondrocytes in calcified cartilaginous zone into bone cells was observed. 2. There were thinning of thickness of each zone of articular cartilage except calcified cartilagnous zone was observed in nonsurgical site. 3. In MT stain of condylar trabeculae, there was increased calcification in nonsurgical site than control and surgical site and the degree of calcification was similar in surgical site and control group. 4. In both site of experimental group no features of degenerative changes were observed. From the above results, it is presumed that the morphologic changes of surgical site discectomy are compensatory remodeling process characterized by an hyperplastic reaction of the articular zone and fibrocartilaginous zone filling the void created by removing the disc, and the bone changes are secondary to changes in the cartilage. Increased degree of calcification seen in condylar trabeculae of nonsurgical site results from the excessive use of condyle of that site.

• The Journal of the Korean bone and joint tumor society
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• v.16 no.2
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• pp.51-54
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• 2010

Purpose: This study was aimed to evaluate the recurrence rate of a giant cell tumor (GCT) of the bone. Materials and Methods: The medical records of fifty four patients who were diagnosed with a giant cell tumor of the bone between March 1980 and December 2008 were analysed retrospectively. Among 54 patients, 27 were men, remaining 27 were women with the mean age of 33.1 years (range, 13-67 years). The mean duration of follow-up was 67.1 months. Results: Twenty-one patients (38.9%) had a local recurrence. The mean time to recurrence was 21.5 months (range, 2-59 months). The local recurrence rate of the upper extremities was higher than that of lower extremities. According to Campanacci classification, patients with a grade I diseae had lower recurrence rate than those with grade II or III disease. There was no significant differences in the recurrence rates based on cryotherapy, the filling of bone cement or bone grafts and surgical margin. Conclusion: To prevent local recurrence of GCT of bone, curettage of the tumor and elimination of the remaining cells are more important than adjuvant therapy.

• Economic and Environmental Geology
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• v.52 no.2
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• pp.189-197
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• 2019

HLW (High Level Radioactive Waste) is one of the problems that must be solved in the countries that implement nuclear power generation. Most countries that are concerned about HLW treatment are considering complete isolation from human society by disposing them deep underground. For perfect isolation, understanding the characteristics of underground rocks is very important. In particular, understanding the characteristics of discontinuity as a path way is one of the first things in order to predict the movement of exposed nuclear species to the surface. In this study, we used 500m underground core samples obtained from granite and gneiss area. The purpose of this study is to understand the characteristics of the discontinuities in each rock type and to analyze the properties of the joints in the underground relative to the surrounding environment. For this purpose, the types of discontinuities were classified and the distribution of each discontinuity were analyzed through visual analysis of the each sample obtained at 500m underground. This study can be used as a basic data for understanding the properties of discontinuities in the rock of the survey area and it can be also used as an important data for understanding the distribution characteristics of discontinuities according to the rock types.

• Journal of the Korean Geosynthetics Society
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• v.17 no.4
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• pp.1-10
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• 2018

Although the soil nailing method is generally used as a gravity grouting, the development and application of pressurized grouting method has recently increased to address the problem of joint generation and filling due to grouting. Pressurized grouting of the soil nailing method is generally used in combination with ordinary portland cement and water. In the field, the cement is mixed with the rapid setting cement to reduce curing time because ordinary portland cement takes more than 10 days to satisfy the required strength. In this study, uniaxial compression tests and laboratory tests were carried out to confirm the efficiency of the grouting material according to the mixing ratio of rapid setting cement. The mixing ratio of 30% grouting satisfies the required strength within 7 days and satisfies the optimum gel time. As a result of the laboratory test with granite weathered soil, the reinforcing effect was confirmed to be 1.5 times as compared with the gravity type at an injection time of 10 seconds and a strain of 15%. The friction resistance increases linearly with the increase of the injection time, but it is confirmed that the friction resistance decreases due to the hydraulic fracturing effect at the injection time exceeding the limit injection pressure. Numerical analysis was performed to compare the stability of slopes not reinforced with slopes reinforced with gravity and pressurized soil nailing.

• Journal of the Korean GEO-environmental Society
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• v.19 no.12
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• pp.59-64
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• 2018

The damages to the reinforced earth retaining wall are divided into the front wall, foundation, drainage and upper slope. Damage of reinforced earth retaining wall is mainly caused by damage caused by drainage problem in the field. Recently, damage caused by snow removal materials have been occurred. Recently, the amount of snow removal materials used in winter is increasing due to abnormal weather. This chlorides degrades the concrete structure, where the reinforced earth retaining wall was no exception. There has recently been a case in which the front wall of the reinforced earth retaining wall deteriorates due to the chlorides introduced into the back filling portion through the drainage passage. Therefore, in this study, the cause of damages of reinforced earth retaining wall constructed in bridge abutment was analyzed, and an analytical study was conducted on the countermeasure. As a result, it was found that chlorides, which was introduced through the drainage system in the expansion joint of the bridge shift part or the upper structure, is infiltrated into the back part of the reinforced earth retaining wall and damaged. Therefore, it is suggested to improve the drainage system and restored the stiffness of the front wall.