• Title/Summary/Keyword: 손상원인

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Fracture Developing History and Density Analysis based on Grid-mapping in Bonggil-ri, Gyeongju, SE Korea (경주시 봉길리 지역의 단열발달사 및 단열밀도 해석)

  • Jin, Kwang-Min;Kim, Young-Seog
    • The Journal of Engineering Geology
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    • v.17 no.3
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    • pp.455-469
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    • 2007
  • The study area, Bonggil-ri, Gyeongju, SE Korea, is composed of Cretaceous sedimentary rocks, and Tertiary igneous rocks and dykes. A research on fracture developing history and density distribution was carried out on well exposed Tertiary granites. The fractures developed in this area have the following sequence; NW-SE trending duo-tile shear bands (set a), NNW-SSE trending extensional fractures (set d), WNW-ESE trending extensional or normal fractures (set b), NE-SW trending right-lateral fractures (set c), WNW-ESE trending reverse fault reactivated from normal faults (set e) and NW-SE trending left-lateral faults reactivated from shear bands (set a) under brittle condition. According to the result of fracture density analysis, the fracture density in this area depends on rock property rather than rock age, and also higher fracture density is observed around fault damage zones. However, this high fracture density may also be related to the cooling process associated with dyke intrusion as well as rock types and fault movement. Regardless of the reason of the high fracture density, high fracture density itself contributes to fluid flow and migration of chemical elements.

Case Study on Fracture Type of Wooden Crib Wall (목재 Crib wall의 파괴유형에 대한 사례연구)

  • Shin, Changgun;Paik, Moonyeol;Hong, Cheolhwa;Bae, Wooseok
    • Journal of the Korean GEO-environmental Society
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    • v.14 no.7
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    • pp.39-50
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    • 2013
  • Crib wall is one of the segmental grid retaining walls using headers and stretchers to establish the framework of the wall. In this method, grids formed by the intersection of headers and stretchers are generally filled with the gravel to maintain the weight of the wall. Therefore, the construction can be carried out with higher speed and much economically when compared with the concrete retaining wall. Furthermore, it has high drain capacity, and environmentally friendly aspects also have been pointed out because the possibility of the planting at the front of the wall. However, in the wooden crib wall method, the relative movement between the individual headers and stretchers was generally recognized, and stress redistribution in the gravel filling was also observed when subjected to the external loading and self-weight of filling. In this study, it was analyzed fracture types and causes of wooden crib wall through detailed investigation and analysis of a large crib wall construction site. As a results, it occurred the damage in the members of 5.7% in a total of 2,315 locations and the damage of header occurred in the members of a header 80.2%. The 65.7% of the damaged header are concentrated in the lower part of crib wall. Therefore, it was analyzed the differences of fracture types and causes of wooden crib wall depending on the installation position and the kinds of members. It is considered basically the members of various forms of distortion and the grain affecting.

Association of Regional Sexual Assaults with Regional Traits in India (인도의 집단 성폭행 사건들과 지역적 특성의 연관성)

  • Kang, Wee-Dal;Lee, Geo-Lyoung
    • The Journal of the Korea Contents Association
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    • v.19 no.12
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    • pp.615-622
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    • 2019
  • Recently, reports of cruel group sexual assault in India have been frequently reported. The most prominent group sexual assault incident in India was a medical student, Joti Singh case, that six men raped her and damaged her genitals and organs on a bus and caused her death in 2012. This incident led to the launch and passage of a strong punishment bill including death penalty for sexual assault. But since then, sexual assault is still on the rise. As a result of examining the relations with regional characteristics centering on the areas where sexual assaults occurred, it was found that most of the cases of group sexual assault reported in the media occurred in the mid-north of India, and this was consistent with the region of the Hindu stressed region. If so, it can only be concluded that Hindu fundamentalism, in which female neglect is severe, is the cause. Hindu fundamentalists try to revive the traditional values of women with a strong retroism tendency. In Indian society, women are still at risk of collateral damage. The pursuit of Hindu fundamentalism by the ruling party and political leaders will require much more time to improve the women's social status and human rights.

Orthodontic treatment of an ankylosed tooth; application of single tooth osteotomy and alveolar bone distraction osteogenesis (유착치의 교정치료; 골절단술과 치조골 신장술의 적용)

  • Kim, Yong-Il;Kim, Seong-Sik;Son, Woo-Sung;Park, Soo-Byung
    • The korean journal of orthodontics
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    • v.39 no.3
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    • pp.185-198
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    • 2009
  • Tooth anklylosis is defined as the adhesion state of alveolar bone to dentin or cementum. Trauma, disturbed metabolic disease, and congenital disease have been given as etiologic factors. Complications of tooth ankylosis are tipping of the neighboring teeth, space loss, and supraeruption of the opposing teeth. Particularly if dental ankylosis occurs in maxillary incisors of a growing child, the ankylosed tooth can not move vertically with subsequent disturbance in vertical growth of the alveolar process. With an appropriate treatment approach, an esthetic condition must be achieved especially in the maxillary anterior region. In this report, two cases are presented which were treated by the surgical repositioning method. One is treated by alveolar bone distraction osteogenesis which used a tooth-borne type distraction device and the other by single tooth osteotomy.

THE SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY FINDINGS IN DEVELOPMENTAL LANGUAGE DISORDERS (발달성언어장애아(發達性言語障碍兒)의 단일광자방출전산화단층촬영(單一光子防出電算化斷層撮影) 소견(所見)에 관한 연구)

  • Park, Jin-Seng;Cho, Soo-Churl;Lee, Myung-Chul
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.3 no.1
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    • pp.46-55
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    • 1992
  • The pathophysiology of developmental language disorder is a highly controversial matter. In order to investigate the neural mechanisms involved in developmental language disorders, the authors studied three dimensional regional cerebral blood flow(rCBF) using Tc-99mH-MPAO in 42 children with developmental language disorders. The results are summarized as follows : 1) 61.9% (26/42) of this series revealed decreased perfusion in SPECT. 2) Regions of hypoperfusion were seen in cerebral cortex(47.6%, 20/42), thalamus(33.3%, 14/42), basal ganglia(11.9%, 5/42) and cerebellum(7.1%, 3/42). This study suggests that developmental language disorder could be due to specific functional impairment of the local brain regions which could not detected by conventional investigations such as brain CT or EEG.

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프레스다이용 코일스프링의 신뢰성평가 및 고장분석 사례 발표

  • Go, Se-Hyeon;Park, Sang-Yong;Jang, Jin-Man;Lee, Won-Sik
    • Proceedings of the Korean Reliability Society Conference
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    • 2006.05a
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    • pp.239-246
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    • 2006
  • 프레스다이용 코일스프링은 자동차 및 전자제품의 외형생산에 필요한 금형 내에 장착되는 금형용 스프링으로서 녹아웃 및 스트리퍼 등에 사용되고 있다. 프레스다이용 코일스프링이 사용 중 파손 시에는 고가인 금형의 손상 및 생산성에 영향을 미칠 수도 있기 때문에 사용 환경에서의 신뢰성확보가 요구되어지고 있다. 특히 중(重)하중 및 극중(極重)하중용 스프링은 과거 현장에서 파손사례가 자주 발생함으로 인해 외산을 선호하는 경향이 있는 형편이다. 이에 국산 스프링의 신뢰성검증 및 확보를 위해 신뢰성기반구축사업을 통해 신뢰성평가기준(RS D 0014)가 제정되었으며, 이 평가기준에 의거하여 국내 업체의 제품에 대해 신뢰성평가를 실시하였다. 프레스다이용 코일스프링의 파손원인은 주로 반복하중에 의한 피로파손과 일정한 변위의 변형으로 발생하는 코일스프링 자유높이의 축소로 크게 구분되어질 수 있다. 시험결과 주 파손양상은 피로에 의한 균열발생이었으며, 코일 끝단부와 끝단부 직하부의 코일과의 마찰에 의한 균열발생이 주원인이었다. 즉, 코일의 끝단면과 직하면 코일이 연속적으로 부딪침으로써 발생한 변형 및 마모에 의해 표면균열이 발생하고, 표면균열에서 반복적인 부하하중이 가해짐으로써 피로균열 진전을 통해 점차적으로 파손이 진행되어졌음을 알 수 있었다. 본 발표에서는 기준에 의거하여 로하중용 프레스 다이용 코일스프링을 평가한 신뢰성평가시험 결과에 대해 보고하고, 파단면 관찰과 외산제품과의 미세조직 및 조성 등의 비교분석결과 등을 기초로 파손원인을 분석한 결과에 대해 보고하고자 한다.제고할 수 있을 것으로 기대한다.X>$CdCl^+,\;CdSO_4$ 등이 형성되었다. 수은의 경우는 해수 및 증류수를 용출용매로 이용한 모든 경우에서 납, 구리, 카드뮴과는 달리 대부분 침전하였다. 더욱이 해수에 존재하는 고농도 염소($Cl^-$)와의 수착으로 인해 finite solid인 calomel($Hg_2Cl_2$)이 형성되어 대부분 침전(SI=0)되기 때문에 납, 구리, 카드뮴 보다 더 낮은 환경이동성을 갖을 것으로 사료된다. 상기 실험결과 용출용매로 증류수와 해수를 이용했을 때, 제강 슬래그에서 용출되는 납, 구리, 카드뮴, 수은의 용출 경향의 차이를 확인할 수 있었고 이에 따라서, 납, 구리, 카드뮴의 용출 유해성은 낮기 때문에 해양구조물로의 제강슬래그 유효이용은 적합할 것으로 판단되었다.im80%$로 계산되었다. 열형광선량계로 측정된 방사선량은 각각 1.8, 1.2, 0.8, 1.2, 0.8 (70 cm 거리) cGy로 측정되었으며, 환자의 복부 표면에서의 서베이메터를 이용한 측정량은 10.9 mR/h였다. 차폐구조물의 사용 시 전체 치료 동안에 태아선량은 약 1 cGy 정도로 평가되었다. 결론 : AAPM Report No.50의 자료에 따르면, 임산부의 방사선 치료 시 태아의 방사선 피폭선량은 5 cGy 이하일 경우에 방사선 피폭에 따른 태아의 위험이 거의 없는 것으로 제시되고 있다. 본원에서 차폐 구조물을 설치하였을 경우에 측정된 태아선량은 약 1 cGy로 측정되었고, 고안된 차폐구조물

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Physiological Activities of Phellinus ribis Extracts (찔레 영지버섯(Phellinus ribis) 추출물의 생리활성)

  • Song, Jae-Hwan;Lee, Hyun-Sook;Hwang, Jin-Kook;Chung, Tae-Young;Hong, Sung-Ryul;Park, Ki-Moon
    • Korean Journal of Food Science and Technology
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    • v.35 no.4
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    • pp.690-695
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    • 2003
  • Physiological activities of 40% ethanol extracts of Phellinus ribis were studied by employing several biological and biochemical assays. The extracts of Phellinus ribis displayed nitrate-scavenging activities (NSA) at pH 1.2 as with 64% NSA with 1.0 mg/mL of the extracts. They also had 91% 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities at the concentration of 1.0 mg/mL. Antioxidant activities of the extracts (at 0.5 mg/mL) on the autoxidation of linoleic acid (p<0.001) were also observed.. The inhibitory effect of the extracts on angiotensin converting enzyme was 11%. Cytotoxic effects of Phellinus ribis extracts against human cancer cell tines were also examined using MTT assay. The extracts (at 50 mg/mL) had severe growth inhibitory effects on A549, Hela, AGS, and SK-Hep-1, which were 8, 44, 76 and 42%, respectively. Ames test indicated that the extracts had no mutating effects on Salmonella typhimurium TA98 and TA100.

Overexpression of MicroRNA-31 as a Promising Biomarker for Prognosis and Metastasis in Human Colorectal Cancer (MicroRNA-31 과발현을 이용한 대장암의 예후예측 및 전이예측 바이오마커 발굴)

  • Hur, Keun
    • Journal of Life Science
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    • v.26 no.6
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    • pp.705-710
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    • 2016
  • Colorectal cancer (CRC) is the third most common cancer and a leading cause of cancer-related death worldwide. Although several diagnostic and therapeutic tools have been available, CRC remains difficult to complete cure because of insufficient understanding of the molecular mechanisms underlying this disease progression. MicroRNAs (miRNAs) are small non-coding RNA molecules that strongly regulate gene expression via transcriptional and translational control mechanisms. Many crucial cellular pathways are frequently disrupted in cancer development process due to dysregulation of several miRNAs. Mir-31 functions as an oncogene that modulate expression of multiple cancer related genes. Thus, we aimed to demonstrate clinical relevance of miR-31 in human CRC. Quantitative RT-PCR analysis of miR-31 expression was performed in 175 CRC tissues and 16 normal colonic mucosa (NM). Next, we investigated clinical significances of miR-31 expression in various clinicopathologic features in CRC patients cohort. Mir-31 was significantly up-regulated in CRC tissues compared to NM. In CRC tissues, miR-31 expression level was significantly elevated in a stage-dependent manner, which was associated with poor survival in patients with CRC. High miR-31 levels in CRC tissues significantly correlated with poor prognosis (hazard ratio [HR]=2.4) as well as distant metastasis (odds ratio [OR]=2.3). In conclusion, we identified clinical significance of miR-31 expression in CRC. High miR-31 expression may be clinically able to use as a biomarker for CRC prognosis and predicting metastasis.

The Ossifying Epulis Accompanying Multi-Nucleated Giant Cells in a Dog (개에서 발생한 거대세포 출현을 동반한 골화성 치은종)

  • Hong, Il-Hwa;Jeong, Won-Il;Son, Young-Sook;Park, Jin-Kyu;Yang, Hai-Jie;Yuan, Dong-Wei;Goo, Moon-Jung;Lee, Hye-Rim;Jeong, Kyu-Shik
    • Journal of Life Science
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    • v.17 no.11
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    • pp.1488-1491
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    • 2007
  • An epulis was occurred on gingiva of 11-year old female dog, Yorkshire terrier. Our case had feature of ossifying epulis but there were a few multi-nucleated giant cells (MGCs). MGCs had osteoclast-like appearance and giant cell epulis usually appears at the site of tooth extraction. Therefore, we suggest that appearance of MGCs in our case may be due to phagocytosis pre-formed osteoid/bone or our case may be mixed epulides of ossifying and giant cell epulis by mixed stimulation of chronic gingivitis and trauma and in flammation by tooth extraction. Thus, MGCs have possibility enough to appear in ossifying epulis, but ossifying epulis accompanying MGCs has not been reported. Therefore, our case may deserves an attention as an unique case and will be helpful to study pathogenesis of giant cell containing lesion of the jaw.

Reliability Assessment and Prediction of Solder Joints in High Temperature Heaters (고온히터 솔더접합부의 신뢰성 평가 및 예측)

  • Park, Eunju;Kwon, Daeil;Sa, Yoonki
    • Journal of the Microelectronics and Packaging Society
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    • v.24 no.2
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    • pp.23-27
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    • 2017
  • This paper proposes an approach to predict the reliability of high temperature heaters by identifying their primary failure modes and mechanisms in the field. Test specimens were designed to have the equivalent stress conditions with the high temperature heaters in the field in order to examine the effect of stress conditions on the solder joint failures. There failures often result from cracking due to intermetallic compound (IMC) or void formation within a solder joint. Aging tests have been performed by exposing the test specimens to a temperature of $170^{\circ}C$ in order to reproduce solder joint failures in the field. During the test, changes in IMC formation were investigated by scanning electron microscopy (SEM) on the cross-sections of the test specimens, while changes in void formation were monitored both by resistance spectroscopy and by micro-computed tomography (microCT), alternately. The test results demonstrated the void volume within the solder increased as the time at the high temperature increased. Also, the phase shift of high frequency resistance was found to have high correlation with the void volume. These results implied the failure of high temperature heaters can be non-destructively predicted based on the correlation.