• The Journal of Engineering Geology
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• v.23 no.4
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• pp.329-340
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• 2013

A geologic survey of the Bukpyeong and Pohang basins, as candidate basins for the geological storage of $CO_2$, was performed to evaluate storage capacity and security. To analyze the mechanical stability of the storage reservoir and cap rocks, we measured the porosity, seismic velocity, uniaxial strength, internal frictional angle, and Young's modulus of core samples recovered from the two basins. It is costly and sometimes impossible to conduct tests over the entire range of drill holes, and continuous logging data do not yield the mechanical parameters directly. In this study, to derive the mechanical properties of geologic formations from the geophysical logging data, we determined the empirical relations between the physical properties (seismic velocity, porosity, and dynamic modulus) and the mechanical properties (uniaxial strength, internal friction angle) of the core samples. From the comparison with our core test data, the best fits to the two basins were selected from the relations suggested in previous studies. The relations between uniaxial strength, Young's modulus, and porosity of samples from the Bukpyeong and Pohang basins are more consistent with certain rock types than with the locality of the basins. The relations between the physical and mechanical properties were used to estimate the mechanical rock properties of geologic formations from seismic logging data. We expect that the mechanical properties could also be used as input data for a modeling study to understand the mechanical instability of rock formations prior to $CO_2$ injection.

• Clinics in Shoulder and Elbow
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• v.5 no.2
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• pp.88-97
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• 2002

The purpose of this study was to compare the outcomes between arthroscopir repair and mini-open repair of medium and large rotator cuff tears in which arthroscopic repair was technically unsuccessful. We evaluated 76 patients of full-thickness rotator cuff tears, among them 42 patients had all-arthroscopic and 34 patients had mini-open salvage repairs. Patients who had acromioclavicular arthritis, subscapularis tear, or instability were excluded. There were 39 males and 37 females with mean age of 56 years (range,42 to 75 years). At a mean follow-up of 39 months (range, 24 to 64 months), the results of both groups were compared with regard to the UCLA and ASES shoulder rating scale s. Shoulder scores improved in all ratings in both groups (p > 0.05). Overall, sixty-six patients showed excellent or gr)of and ten patients showed fair or poor scores by the UCLA scale. Seventy-two patients satisfactorily returned to prior activity. Four showed unsatisfactory return. The range of motion, strength, and patient's satisfaction were improved postoperatively. There were no difference in shoulder scores, pain, and activity return between the arthroscopic and mini-open salvage groups (p > 0.05). However, Patients with larger size tear showed lower shoulder scores and less predictive recovery of the strength and function (p < 0.05). Postoperative pain was not different with respect to the size of the tear (p : 0.251). Arthroscopic repair of medium and large full-thickness rotator cuff tears had iln equal outcome to technically unsuccessful arthroscopic repairs, which were salvaged by conversion to a mini- open repair technique. Surgical outcome depended on the size of the tear, rather than the method of repair.

• Clinics in Shoulder and Elbow
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• v.2 no.1
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• pp.41-46
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• 1999

Glenoid labrum acts as one of static stabilizer of the glenohumeral joint. It deepens the glenoid socket and may also serve as a chock, acting as a wedge in preventing glenohumeral translation. Two types of variations in labral anatomy were noted by Detrisac and Johnson. Type A has a superior labrum that is detached centrally but well attached peripherally. The type B labrum is well attached centrally and peripherally at all sites. A meniscoid-type labrum is thought to be normal unless there are splits or fragmentation of the overlying labral tissue. Meniscoid type labrum is different from SLAP II lesion in that it has a firm anchoring on the superior labrum. We observed four cases that had a meniscoid variant superior labrum, which covered the superior glenoid unusually larger than normal in the arthroscopic treatment of shoulder pathology including instability and rotator cuff diseases. We did arthroscopic reshaping and debridement of meniscoid variant superior labrum combined with pathologic change of the glenohumeral joint. Further study would be required for understanding the mechanism of the development of meniscoid variant labrum and its clinical significance.

• The Journal of the Korea Contents Association
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• v.17 no.6
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• pp.382-395
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• 2017

This study attempted to examine how sexually abused women with intellectual disability living in residential care facilities interact with their environment, such as personal life, family and communities, and to identify contextual characteristics and needs of these women. Qualitative case study method was adopted, and data was collected through individual and intake interviews, participant observation and a survey with 11 participants residing in a residential care facility for sexually abused women with intellectual disability. The results showed that participants struggled with stresses and emotional instability affected by traumatic experiences of sexual abuse. Family was a system that sexual abused took place, while the systems of residential facilities protected them from potential dangers and violence. Work and school systems also provided them opportunities of learning and having dreams in the future. However, the community system which participants would live after discharging from the facility, had risk factors vulnerable to sexual violence against participants. In conclusion, this study suggested diverse services and programs, such as professional psychotherapy programs, integrated support programs for victim and their families and provision of professional care facilities.

• The Korean Journal of Applied Statistics
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• v.21 no.1
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• pp.141-149
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• 2008

Recently we frequently analyze multivariate data with quite large number of variables. In such data sets, virtually duplicated variables may exist simultaneously even though they are conceptually distinguishable. Duplicate variables may cause problems such as the distortion of principal axes in principal component analysis and factor analysis and the distortion of the distances between observations, i.e. the input for cluster analysis. Also in supervised learning or regression analysis, duplicated explanatory variables often cause the instability of fitted models. Since real data analyses are aimed often at multiple purposes, it is necessary to reduce the number of variables to a parsimonious level. The aim of this paper is to propose a practical algorithm for selection of a subset of variables from a given set of p input variables, by the criterion of minimum trace of partial variances of unselected variables unexplained by selected variables. The usefulness of proposed method is demonstrated in visualizing the relationship between selected and unselected variables, in building a predictive model with very large number of independent variables, and in reducing the number of variables and purging/merging categories in categorical data.

• Journal of Veterinary Clinics
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• v.23 no.3
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• pp.291-299
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• 2006

During long bone lengthening, there are many disadvantages including axial deviation, malalignment and re-fracture which are commonly encountered inspite of its proven abilities. To study the effects of intramedullary K-wire application on the lengthening of long bone, ten skeletally mature mongrel dogs were separated into two groups(Group I, II). Right femurs of group I(5 dogs) were fixed with only monolateral external fixator after subperiosteal osteotomy. Right femurs of group II(5 dogs) were fixed with mono lateral external fixator and intramedullary K-wire after subperiosteal osteotomy. Lengthening was started at 7 days after the surgery with the rate of 0.5 mm per day for 5 weeks and the dogs were sacrificed after 15 weeks postoperatively to examine histologic differences and evaluate bone mineral density. Radiographic examination at an interval of two weeks was done to evaluate the type of callus formed and to analyze complications including instability of external skeletal fixation and axial deviation. Bone mineral density at the lengthened area and contralateral nonlengthened area were measured using quantitative computerized tomography. Histological examination of regenerated bone was performed using Masson's trichrome stain method. The radiographs demonstrated poor callus formation, higher incidence of axial deviation and screw loosening in the group I compared to the group II. The bone mineral density at the lengthened area in the group II was higher than that of the group I(P<0.05). Histological examination showed that the new bone trabeculae in the group II were greater than that of the group I. In conclusion, the combination of monolateral external fixator and intramedullary K-wire can prevent pin loosening, axial deviation and reduce healing period in dogs.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.29-29
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• 2011

아라미드 섬유는 열에 강한 튼튼한 방향족 폴리아마이드 섬유이다. 아마이드는 "85%이상의 아미드(CO-NH)기가 두 개의 방향족 고리에 직접 연결된 합성 폴리아미드로부터 제조된 섬유"로 정의된다. 아라미드 섬유는 크게 파라계와 메타계로 대별되는데 본 연구에서 사용한 파라계 아라미드는 인장강도, 강인성, 내열성이 뛰어나며 고강력 고탄성률을 지니고 있다. 일반적인 유기 섬유와는 다른 우수한 성질을 바탕으로 부직포, UD laminatig, staple 등의 형태로 크게 섬유보강 고무 복합재료 등의 각종 복합재료, 로프, 케이블, 방탄방호용과 같은 산업자재의 용도로 자동차, 우주항공, 정보통신, 국방, 등 다양한 관련 산업분야에서 사용이 확대되고 있는 고부가 소재이며 가격대비 성능비가 우수하기 때문에 세계적으로 산업용 섬유 및 초고성능 섬유시장에서 비중이 증가될 것으로 예상되고 있다. 본 연구에서는 Para-Aramid 필라멘트를 이용하여 ATY를 생산할 때 제조공정조건에 따른 ATY 물성을 알아보고 고강도를 요구하는 방화복, 고무 보강용 섬유 등의 소재에 맞는 ATY 사가공 최적공정조건을 도출하여 체계화된 data-base를 구축하여 생산성 향상 및 품질개선과 함께 산업자재용 직물개발에 응용하고자 한다. 아라미드를 ATY로 제조할 경우, 표면에 생기는 loop로 인하여 타소재와 접착시, 접착제 담지 성능이 향상되어 접착력이 상승되는 반면, 아라미드 ATY가 기존의 아라미드의 물성보다 저하되는 약점을 가지고 있으므로 이를 보완하기 위해 본 연구에서는 ATY 제조공정에서 중요 공정인자인 사속, heater 온도, over feed ratio를 변화시켜 시료를 제조하여 이들의 물성을 분석하여 최적의 물성을 갖는 ATY 사가공 공정을 도출함으로써 물성이 저하되는 문제를 보완 가능할 것으로 기대된다. 물성분석은 강신도, 초기탄성률을 각각 측정하여 인장특성을 확인하였으며, 습열수축률과 건열수축률을 측정하여 시료의 열수축률에 대해 측정을 하였다. 표면의 루프 발현 정도를 보기 위하여 Crimp Rigidity(CR%), 형태 불안정성(instability)등을 측정하였으며, 영상 현미경 시스템을 사용하여 ${\times}40$ 배율로 표면특성을 측정하였다.

• Journal of the Korean Arthroscopy Society
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• v.9 no.2
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• pp.194-200
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• 2005

Purpose: To evaluate the short-term follow up outcome and the effectiveness of arthroscopic vertical shift of anteroinferior capsulolabral complex, plication of AIGHLC (anterior band of inferior glenohumeral ligament complex) and thermal capulorraphy, posteroinferior suture plication, rotator interval closure as an adjuncts in recurrent instability of megafrequency with night time dislocation. Materials & Methods: From March 1998 to February 2004, we have had 18 shoulders out of 156. All of the cases have been night time dislocation above more one time. The age were average 29.4$(21{\sim}37)$ year old. The average follow up were 21.1 $(12{\sim}45)$months We checked Rowe score and ROM at pre-operation, post-operation 6 months,1 year & last follow up period. Results: Above good results were 16 cases(88.9%). The excellent were 6 cases, good were 10, fair 1, poor 1. Conclusions: In recurrent anterior shoulder dislocation in greater than 50 frequency, arthroscopic stabilization can be an alternative technique for selected patients against open inferior capsular shift. But more long ter n follow up and large materials will be needed in the future study.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.5
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• pp.509-517
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• 2008

DNA damage accumulates in cells as a result of exposure to exogenous agents such as benzopyrene, cigarette smoke, ultraviolet light, X-ray, and endogenous chemicals including reactive oxygen species produced from normal metabolic byproducts. DNA damage can also occur during aberrant DNA processing reactions such as DNA replication, recombination, and repair. The major of DNA damage affects the primary structure of the double helix; that is, the bases are chemically modified. These modification can disrupt the molecules'regular helical structure by introducing non-native chemical bonds or bulky adducts that do not fit in the standard double helix. DNA repair genes and proteins scan the global genome to detect and remove DNA damage and damage to single nucleotides. Direct reversal of DNA damage, base excision repair, double strand break. DNA repair are known relevant DNA repair mechanisms. Four different mechanisms are distinguished within excision repair: direct reversal, base excision repair, nucleotide excision repair, and mismatch repair. Genetic variation in DNA repair genes can modulate DNA repair capacity and alter cancer risk. The instability of a cell to properly regulate its proliferation in the presence of DNA damage increase risk of gene mutation and carcinogenesis. This article aimed to review mechanism of excision repair and to understand the relationship between genetic variation of excision repair genes and head and neck cancer.

• Membrane Journal
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• v.17 no.3
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• pp.219-232
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• 2007

The polyethersulfone(PES)-titanium oxide($TiO_2$) hybrid membranes were prepared by immersion precipitation phase inversion method. The casting solution for the preparation of $PES-TiO_2$ hybrid membrane was provided by adding $TiO_2$ nano particles into the basis polymer solution of 14 wt% and 20 wt% PES/N-methyl-2-pyrrolidone(NMP). The $TiO_2$ loading [wt% ($TiO_2/NMP$)] in eating solution was varied from 0 to 60 wt%. Membrane performance and morphological change of the resulting $PES-TiO_2$ hybrid membranes were discussed in aspect of $TiO_2$ loading, by viscosity, coagulation value and light transmittance of the casting solution, measurement of tensile strength, pore size and contact angle, surface and cross sectional SEM images of the hybrid membrane, and ultrafiltration experiments using the hybrid membrane. According as increase of $TiO_2$ loading in the casting solution, viscosity is increased and coagulation value becomes lower, therefore the thermodynamic instability of the casting solution is increased. It is found that when $TiO_2$ loading is increased, 1) precipitation rate becomes faster while instantaneous demixing is maintained, 2) pure water flux, membrane pore size and compaction stability of the resulting membranes are increased, 3) tensile strength and contact angle are decreased. Dead-end ultrafiltration of bovine serum albumin(BSA) solution using the hybrid membrane shows that membrane performance(flux of BSA solution) enhanced up to 7 times compared with the results obtained using the pure PES membrane(not containing $TiO_2$ particle), due to the increase of hydrophilicity.