• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.2
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• pp.127-140
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• 2015

A fault is one of the critical factors that may lead to a possible ground collapse occurring in construction site. A fault core, however, possibly acting as a failure plane in whole fault zone, is composed of fractured rock and gouge nonuniformly distributed and thus can be characterized by its wide range of shear strength which is generally acquired by experimental method for stability analysis. In this study, we performed direct shear test and grain size distribution analysis for 62 fault core samples cropped from 12 different spots located in the vicinity of Kyongju and Ulsan, Korea. As a result, the range of shear strength representing the characteristics of fault cores in the study regions is determined with regard to vertical stress using a regression analysis for experiment data. The weight ratio of gravels in the samples is proportional to the shear strength and that of silt and clay is in inverse proportion to the shear strength. For most samples, the coefficient of determination is over 0.7 despite of inhomogeneity of them and consequently we determined the lower limit and upper limit of the shear strength with regard to the weight ratio by setting the confidence interval of 95%.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.813-818
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• 2014

Aims: To describe our institutional experience with high dose rate (HDR) interstitial brachytherapy (IBT) compared with previously reported results on the low dose rate (LDR) practice for head and neck cancer. Materials and Methods: Eighty-four patients with oral cavity (n=70) or oropharyngeal cancer (n=14) were treated with 192Ir HDR-IBT. Seventy-eight patients had stage I or II tumour. The patients treated with IBT alone (n=42) received 39-42 Gy/10-14 fractions (median=40 Gy/10 fractions). With respect to the combination therapy group (n=42), prescription dose comprised of 12-18 Gy/3-6 fractions (median=15 Gy/5 fractions) for IBT and 40-50 Gy/20-25 fractions (median=50 Gy/25 fractions) for external radiotherapy. Brachytherapy was given as 2 fractions per day 6 hours apart with 4 Gy per fraction for monotherapy and 3 Gy per fraction for combination therapy. Results: Four patients were not evaluable in the analysis of outcome. The primary site relapse rates were 23.8% (10/42) and 68.4% (26/38) in patients treated with IBT alone and combination therapy, respectively (p<0.001). Salvage surgery was performed in 19 patients. The 5-year local control rate was estimated at 62% and the disease-free survival (DFS) rate at 52% for all patients. Local control with respect to T1 and T2 tumours was 84% and 42%, respectively. Conclusions: Our present series on HDR-IBT and the previous report on LDR-IBT for head and neck cancer demonstrated similar DFS rates at 5 years (52%). The rate of regional failure in node-negative patients was <20% in both of our series. HDR-IBT offers similar results to LDR-IBT for head and neck cancer.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.2
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• pp.94-102
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• 2020

Precast concrete segment arch system has an economic and construct ability that combined with advantage of precast concrete and arch behavior. A precast concrete segment arch system with outrigger is consisted of segmented precast panels, a steel outrigger rib, and V-strip to connect precast panels with a steel outrigger rib and cast-in-place anchors in precast panels to connect V-strip should have sufficient pull-out capacity to form its arch shape by site lifting for assembled precast panels and outriggers. However, it is difficult to secure its embedment depth due to the relatively shallow thickness of precast panel. It can be also occurred that flexure deformation of precast panels caused by its pull-out behaviors. In this study, pull-out capacity of cast-in-place anchor was examined for construction of precast concrete segment arch system with outriggers. Therefore, a total of 24 precast panel specimens were fabricated to examine pull-out capacities of cast-in-place anchor in precast panels, and installation depth of anchors, diameter of anchors and wire mesh effects for the precast panel were examined. From this pull-out tests, its pull-out capacities and failure modes were evaluated and the type of the cast-in-place anchor applicable to the precast concrete segment panel arch system with outriggers was determined from comparison of the design specification values.

• Herbal Formula Science
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• v.16 no.2
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• pp.11-29
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• 2008

Objective : The aim of this study was to analyse the latest trend of medical science articles about Bojungikki-Tang published in Japan. Methods : We searched medical science articles published from 2003 to 2008 in Japan on the web site, CiNii and then these articles were reviewed and classified according to experimental subject and method. Results : Fifty-two articles, related to Bojungikki-Tang were searched and these were classified into three classes, pharmacological signaling studies, clinical case studies and the others. As a result of classification, clinical case studies were most abundant by 38 cases, pharmacological signaling studies were 10 and the others were 4. This result suggested that the study of Bojungikki-Tang was mainly focused on clinical study rather than experimental study. Among the clinical case studies, clinical studies related to immune disease took the most greatest number and number of other clinical studies were evenly distributed over the various disease. Immune intensification effect of Bojungikki-Tang can be thought continuous with reinforce the middle Jiao Qi in company with improvement effect on growth hormone failure and male infertility. A fact that the one prescription, Bojungikki-Tang could be used to treat various diseases reflects a viewpoint of Oriental medicine that is based on the respect for and understanding of individual constitution and disposition while paying attention to the gender difference and individuality. The clinical usefulness of Bojungikki-Tang on obstructive sleep apnea syndrome and visceroptosis concerns with ascend Yang and treat Qi sinking. Pharmacological signaling studies were mainly focused on diseases that were treated Bojungikki-Tang in clinic, however, there was one study that experimented on changes of numerous gene expression according to the treatment of Bojungikki-Tang using DNA array. Conclusion : The therapeutic system of Oriental medicine is different in various aspects form that of Western medicine and appropriate harmonization of east and west is expected to improve the quality of medical care. In this regard, continuous investigation and analysis about herbal medical science papers in Japan can also be useful to make progress in Korean traditional medicine.

• Journal of Conservation Science
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• v.28 no.2
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• pp.153-164
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• 2012

The major petroglyphs of Bangudae site were composed mainly of hornfelsed shale. Surface of the rock was formed weathering layer (average porosity 25%) that discriminated mineral and chemical composition against fresh rock (average porosity 0.4%). The lost area of major petroglyphs in the past up images carved to the present was calculated about 23.8%. And occurrence area of exfoliation indicated 1.2% of the whole petroglyphs. As a result of the chromaticity analysis, color of the major petroglyphs was changed brighter and yellower than fresh rock by chemical and biological weathering factors. Average ultrasonic velocity of petroglyphs was measured 2,865m/s. This result indicated that ultrasonic velocity decreased especially bottom of petroglyphs than measured result in 2003 year. The results of the evaluation for slope stability, it identified the possibility of toppling, planar and wedge failure in host rock. The 3D image analysis and modeling data of the cavern obtained for structural reinforcement.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.6
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• pp.482-488
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• 2011

Seadike is a coastal structure constructed in the rear region of the foreshore to maximize its usability by preventing direct effect of wave. The expected construction field is determined under the design wave and tidal condition where minor wave overtopping is anticipated. Thus, the location of seadike is generally fixed at the highest site of the surrounding area with seadike crest height controlling the permissible range of wave overtopping volume. But a lot of times, frontal sand beach of the seadike continuously deforms due to incident waves, resulting failure in maintaining its initial slope. The erosion and deposition of the seadike front cause changes in the crest height and volume of wave overtopping and decrease in the setting depth of the seadike, which endangers seadike region as a result. In this study, the relation of local scouring and setting depth of the seadike front in the run-up region is examined by using 2D hydraulic model tests and numerical simulations by modified SBEACH model. As a result, the study learned that if appropriate boundary condition is applied to the modified SBEACH model, it is possible to create practical estimations on the local scouring at the seadike foot when erosive waves flow into the region.

• Korean Journal of Animal Reproduction
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• v.18 no.4
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• pp.299-307
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• 1995

The goal of cell stem cell technology is to produce a viable and genetically normal animal. To achieve this goal various laboratories have followed 2 different pathways beginning with either the culture of 1) single or pooled ICMs grown with or without a feeder layer or 2) single or pooled 16-20 cell stage embryos grown with a feeder layer. Also, thus far embryonic cell cultures or lines have been established by several methods including loose suspension culture for short-term cultures and more commonly murine or bovine fibroblast feeder layers for long-term culture. Pluripotent lines have been derived from 16-cell through blastocyst inner cell mass stages. The efficiency of establishing cell lines and cell proliferation apper to be affected by the number of cells or embryos starting the line. Most attempts to produce offspring from long term STO cell feeder layer cultured ICM or morulae derived ES cells have resulted in pregnancy failure in the first trimester when ES cells were used in cuclear transfer or have failed to retain ES cells in the progeny produced by chimerization. The exception is 1 chimeric fetus from use of morula ES cells in the chimerization with early embryonic cells. There is much to be learned yet about ES cell culture requirements for maintenance of totipotency. If bovine ES cell lines loose imprinting pattern and totipotency with long-term culture and passage as suggested for mouse ES cells, we may be limited to the use of short-term cultures for multiplication of embryos and efficient production of transgenic animals. No bovine ES cell system has yet met all of the criteria indicated for a totipotent ES cell line.

• International Journal of Highway Engineering
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• v.20 no.1
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• pp.87-95
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• 2018

PURPOSES : A geo-grid pavement, e.g., a stress-absorbing membrane interlayer (SAMI), can be applied to an asphalt-overlay method on the existing surface-pavement layer for pavement maintenance related to reflection cracking. Reflection cracking can occur when a crack in the existing surface layer influences the overlay pavement. It can reduce the pavement life cycle and adversely affect traffic safety. Moreover, a failed overlay can reduce the economic value. In this regard, the objective of this study is to evaluate the bonding properties between the rigid pavement and a SAMI by using the direct shear test and the pull-off test. The predicted fractural energy functions with the shear stress were determined from a numerical analysis of the moving average method and the polynomial regression method. METHODS : In this research, the shear and pull-off tests were performed to evaluate the properties of mixtures constructed using no interlayer, a tack-coat, and SAMI with fabric and without fabric. The lower mixture parts (describing the existing pavement) were mixed using the 25-40-8 joint cement-concrete standard. The overlay layer was constructed especially using polymer-modified stone mastic asphalt (SMA) pavement. It was composed of an SMA aggregate gradation and applied as the modified agent. The sixth polynomial regression equation and the general moving average method were utilized to estimate the interlayer shear strength. These numerical analysis methods were also used to determine the predictive models for estimating the fracture energy. RESULTS : From the direct shear test and the pull-off test results, the mixture bonded using the tack-coat (applied as the interlayer between the overlay layer and the jointed cement concrete) had the strongest shear resistance and bonding strength. In contrast, the SAMI pavement without fiber has a strong need for fractural energy at failure. CONCLUSIONS : The effects of site-reflection cracking can be determined using the same tests on cored specimens. Further, an empirical-mechanical finite-element method (FEM) must be done to understand the appropriate SAMI application. In this regard, the FEM application analy pavement-design analysis using thesis and bonding property tests using cored specimens from public roads will be conducted in further research.

• Journal of Trauma and Injury
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• v.22 no.1
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• pp.77-86
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• 2009

Purpose: The appropriate management of traumatic truncal arterial injury is often difficult to determine, particularly if the injury is associated with severe additional truncal lesions. The timing of repair is controversial when patients arrive alive at the hospital. Also, there is an argument about surgery versus stent-graft repair. This study's objective was to evaluate the appropriate method and the timing for treatment in cases of truncal abdominal injury associated with other abdominal lesions. Methods: The medical records at Ajou University Medical Center were reviewed for an 8-year period from January 1, 2001, to December 31, 2008. Twelve consecutive patients, who were diagnosed as having had a traumatic truncal arterial injury, were enrolled in our study. Patients who were dead before arriving at the hospital or were not associated with abdominal organ injury, were excluded. All patients involved were managed by using the ATLS (Advanced Trauma Life Support) guideline. Data on injury site, the timing and treatment method of repair, the overall complications, and the survival rate were collected and analyzed. Results: Every case showed a severe injury of more than 15 point on the ISS (injury severity score) scale. The male-to-female ratio was 9:3, and patients were 41 years old on the average. Sites of associated organ injury were the lung, spleen, bowel, liver, pelvic bone, kidney, heart, vertebra, pancreas, and diaphragm ordered from high frequency to lower frequency. There were 11 cases of surgery, and one case of conservative treatment. Two of the patients died after surgery for truncal organ injury: one from excessive bleeding after surgery and the other from multiple organ failure. Arterial injuries were diagnosed by using computed tomography in every case and 9 patients were treated by using an angiographic stent-graft repair. There were 3 patients whose vessels were normal on admission. Several weeks later, they were diagnosed as having a truncal arterial injury. Conclusion: In stable rupture of the truncal artery, initial conservative management is safe and allows management of the major associated lesions. Stent grafting of the truncal artery is a valuable therapeutic alternative to surgical repair, especially in patients considered to be a high risk for a conventional thoracotomy.

• Archives of Reconstructive Microsurgery
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• v.3 no.1
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• pp.72-80
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• 1994

There are several methods to reconstruct an amputated or lost thumb such as toe to thumb transfer, pollicization and other variety of free flaps. In 1980, Morrison and O'Brien advocated reconstruction of the thumb with a free wrap-around flap from the big toe to recreate a stable, sensate and functional digit, including the nail. From March, 1982 to December, 1992, thirty cases of thumb reconstructions were performed using the wrap-around procedure at Korea University Hospital. 1. 29 cases of total 30 cases were successful and can be obtained the excellent results in functional and cosmetic aspect. 2. In postoperative complications, one case is graft failure, six cases in partial skin necrosis, one case in malunion, 15 cases in resorption of grafted bone piece were come out. 3. Even if the 1st metacarpal neck amputation is occurred, thumb reconstruction with a free neurovascular wrap-around flap was also possible, however, the limitation of the mobility of the reconstructed thumb and resorption of grafted bone piece were come out. We concluded that cosmesis and fuctional results were quite satisfactory despite of some complications. The thumb reconstruction with a wrap around free flap from the big toe in thumb amputated patients is the excellent method in the cosmetic and functional aspect and can be considered as the most useful method because of less morbidity to the donor site and the operator should be trained to get the meticulous microsurgical technique and to detect the complications.