• Journal of Welding and Joining
• /
• v.17 no.2
• /
• pp.25-28
• /
• 1999

국내에 건설되어 거의 20∼30년 가동되고 있는 발전설비, 석유화학 플랜트 등 거대설비 기기의 건전성(integrity) 및 신뢰성 확보와 잔존수명 예측을 위해서는 구조물 내부 또는 표층부에 존재하는 결 함의 특성을 아는 것과 함께 그 재료의 특정 부위에 어느정도의 응력이나 변형이 있는가를 아는 것이 매우 중요하다. 일반적으로 강 용접부의 비파괴적 결함검출에는 주로 SV파(vertically shear wave)와 SH파(horizontally shear wave)라 불리는 횡파를 이용한 초음파사각탐상법이 실용화되어 이용되고 있다. 그러나 비파괴적인 방법에 의한 실험적인 잔류응력 측정, 변형해석법에는 전기 저항 및 자기 스트레인 게이지법, X선회절법, 광탄성법(photoelasticity), 모아레(Mohr's)법, 레이저스펙클(Laser speackle)법, 응 력도료법, Barkhausen Nosise법, Caustics법 등이 제시되어 있으나 그 유용성 면에서는 아직 해결되야할 문제가 많이 남아 있는 실정이다. 응력이나 변형을 해석하는 방법으로 이론적 방법, 계산적 방법 실험적 방법이 잇다. 이론적 방법에는 재료 역학적으로 취급하는 방법, 탄성론 등이 있고, 계산적인 방법에는 유한요소법이 있지만, 이론적 방법이나 계산적 방법만으로는 해석이 불가능한 경우가 많기 때문에 실험 적 방법이 필요하게 된다. 이 글에서는 파괴 시험 또는 다른 비파괴평가기술에 비해 간편한 측정, 높은 측정정도, 시험결과 도출의 신속성, 검사비용의 절감 등 많은 장점을 가지고 있고 실험적으로 유용성이 일부 검증되고 있는 음탄성법(Acoustoelasticity)에 의한 잔류응력 측정법에 관해 소개하고자 한다.TEX> mg/L(평균 49 mg/L)로 비교적 안정적인 처리효율을 보여주었다. 본 연구결과 HVC 공정은 화학약품 사용량의 절감 및 이에 따른 화학슬러지 발생량의 감소를 기대 할 수 있는 친환경기술로 유지관리비를 최소화할 수 있는 장점이 있었다. 않은 사람들 중 미래의 검진실행의지에 건강소식지가 영향을 미친 경우는 48.7%였다. 보건교육을 받은 후 유방암 자가검진 실천율은 사업군에서 53.9%로 받기 전의 27.3%보다 증가하였으나 대조군의 경우는 별 차이가 없었다. 연령별로는 60대가 가장 높았고 사업군에서 검진율의 증가분은 30대가 가장 컸다. 교육수준별로는 사업군은 고졸이, 대조군은 전문대졸이 가장 높았고 사업군에서 검진율의 증가분은 고졸에서 가장 컸다. 보건교육 후 유방암과 관련된 건강지식의 정도는 사업군이 3.7점으로 대조군보다 유의하게 높았으며, 유방암 자가검진법을 실천하는 사람들의 동기는 ‘일반 대중매체의 영향’이 가장 많았으며 건강소식지가 동기인 경우도 20.4%였다. 사업군에서 건강소식지가 유방암 자가검진법 실천에 영향을 미친 경우가 79.6%였으며 유방암 자가검진법에 관한 보건교육을 받고 실천하지 않은 사람들 중 미래의 실천의지에 건강소식지가 영향을 미친 경우는 43.6%였다. 이상의 소견에서 지역주민을 대상으로 인쇄매체를 통한 보건교육은 인쇄물만으로도 쉽게 실천 할 수 있는 유방암 자가검진법이 가장 효과적이었으며, 자궁암검진에 관해서도 검진을 받을 수 있도록 지역사회의 보건의료의 하부구조를 정비하여 제도적 장치를 마련하고 정보를 제공한다면 자궁암검진 실천율도 증가할 것이다.고 12.9% 의 발달율을 보여 유의적인 차이를 보이지 않았다. 이상의 결과로 보아 핵이식 수정란을 효율적으로 생산하기 위하여

• Childhood Kidney Diseases
• /
• v.17 no.2
• /
• pp.122-126
• /
• 2013

Cystinuria is an autosomal recessive disease characterized by impaired transport of cystine and dibasic amino acids in the proximal renal tubule, resulting in the formation of cystine stones. It is believed to account for about 1% of all kidney stones and up to 10% of pediatric stones. Here we report a case of cystinuria with multiple renal stones confirmed by genetic mutational analysis. An 8-month-old girl was admitted to AMC with persistent fever and multiple renal stones. A renal sonogram showed multiple stones at the right renal pelvis, right distal ureter, and left renal medullary portion. An approximately 1 cm renal stone was extracted spontaneously, and stone analysis revealed it to be composed entirely of cystine. Cystinuria was confirmed by increased urine dibasic amino acid levels, including cysteine, and genetic mutational analysis showed the patient to be a homozygote for the pathogenic c. 1820del (p.L607fs) of SLC3A1. Despite treatment with oral hydration and urinary alkalinization, and restricted intake of animal protein, the stones increased in size and number. The patient has since been treated with tiopronin.

• Journal of the Korea Institute of Building Construction
• /
• v.19 no.3
• /
• pp.263-272
• /
• 2019

Building Information Modeling (BIM) and modular construction are regarded as important technologies that have contributed to advancements in the construction industry. However, the utilization of BIM in current modular construction projects is limited; moreover, there are no specific guidelines pertaining the applications of BIM in modular construction projects. Therefore, this study aims to analyze the utilization of BIM for onsite construction planning in modular construction projects. First, a realistic BIM application was selected through literature review and expert interviews. Then, the construction plan of the modular projects was analyzed to classify the BIM application items into five different categories. The utilization of BIM in each category was then analyzed in terms of necessity and efficiency using a questionnaire. Finally, the BIM Utilization Index (BIM UI) was suggested based on the findings of the survey. As a results, the BIM UI for module point details, lifting plan, other installation details, site layout plan, and schedule plan was 0.811, 0.787, 0.770, 0.729, and 0.699, in the descending order of usability. In addition, through the findings of the study and interviews with experts, a case study for implementation of BIM in modular construction plan was conducted. The results of this study can be used as application guidelines for BIM in future modular construction projects.

• Journal of Conservation Science
• /
• v.37 no.2
• /
• pp.179-189
• /
• 2021

In this study, the research objects are gilt plated silver-iron nails excavated from the west of the tombs in Neungsan-ri, Buyeo. A gilt plated silver-iron nail was fabricated by combining silver and iron via heating and then gilding amalgam on top of this combination, demonstrating that this ancient artifact that can be replicated using current technology. Since the metal (Au, Ag) surface of these gilt plated artifacts are covered with iron oxide, which slips into the cracks and scratches of the artifacts as well, desalination is essential. Based on the results of the preliminary experiment, the research objects were classified into grades A, B, and C, according to the degree of corrosion and then desalinated using an alkali solution (NaOH, Sodium Sesquicarbonate of 0.1 M) at 60℃. The results demonstrate that the more serious is the degree of corrosion, the more is the amount of Cl^- detected. Further, more Cl^- was released when NaOH was used than when sodium sesquicarbonate was used, for all grades except Grade A. Furthermore, the more serious is the degree of corrosion, the longer is the desalination period and the reaction with NaOH for all grades except Grade A. A comparison of the Fe composition of the surface before and after desalination shows that Fe composition is the use of NaOH resulted in a smaller increase compared with the use of sodium sesquicarbonate, for all grades except Grade B. However, four of the nails were damaged owing to NaOH (Grade B 3ea, Grade C 1ea) during desalination. Thus, Cl^- ions are more stably released when sodium sesquicarbonate is used than when NaOH is used.

• Journal of Life Science
• /
• v.33 no.12
• /
• pp.987-994
• /
• 2023

This study examined the associations between the genotypes of the galactose mutarotase (GALM) gene and carcass traits in the Hanwoo population of Jeju Island, South Korea. The GALM genotypes were determined by the 14-bp (5'-GGTCTAATGACCAG-3') insertion/deletion (InDel) polymorphisms of the 3'-untranslated region (UTR). All three genotypes (LL, LS, and SS) were found in the Hanwoo steer population. The association analysis showed significant associations between genotypes and several carcass traits, including traits related to intramuscular fat content, such as meat quality, marbling score, and backfat thickness (p<0.05). Animals harboring the SS genotype showed not only higher levels of intramuscular fat content but also lower levels of backfat thickness than animals harboring the LL and LS genotypes. On the other hand, no significant associations were found between the GALM genotypes and carcass weight, eye muscle area, meat color, or fat color (p>0.05). Deleting the 14-bp segment in the 3'-UTR resulted in the modification of the secondary structure of RNA and appeared to affect gene expression by interfering with the binding ability of GALM mRNA with RNA-binding proteins and microRNAs. These results suggest that the 14-bp InDel polymorphism in the 3'-UTR region of the GALM gene affects cattle growth traits and carcass quality through galactose metabolism-mediated fat accumulation in muscle and backfat tissues.

• The korean journal of orthodontics
• /
• v.36 no.3 s.116
• /
• pp.188-197
• /
• 2006

Fiber reinforced composite (FRC) is usually used as a connector joining a few teeth into one unit in orthodontics. However, fracture often occurs during the two to three years of the orthodontic treatment period due to repeated occlusal loading or water sorption in the oral environment. We simulated the repair by overlapping and attaching portions of two FRC strips in the middle and performed a three-point bending test to investigate the changes of the repair strength among the different FRC groups. The specimens were grouped according to the overlapping lengths of the two FRC strips, which were 1, 2, 3 and 4 mm (group E1, E2, E3 and E4, respectively) and the control group consisted of unrepaired, intact FRC strips. Each group consisted of 6 specimens and were cured with a light emitting diode curing unit. Group E4 showed the highest maximum loads of 2.67 N, then the control group (2.39 N), group E3 (2.35 N), E2 (2.10 N), and E1 (1.75 N) in decreasing order. Group E4 also showed the highest stiffness, which was 2.32 N/mm, however, the stiffness of group E3 (2.06N/mm) was higher than that of the control group (1.88 N/mm). According to the visual examination, the specimens tended to be bent rather than being fractured into two pieces with an increased length of overlapping portions. The above results suggest that a minimum overlapping length of 3 mm was necessary to obtain an adequate repair of a 10 mm length of FRC connector. In addition, the critical section adjacent to the joint area, where the thickness decreased abruptly, should be reinforced with flowable resin to minimize the bending tendency.

• The Journal of Korean Academy of Prosthodontics
• /
• v.47 no.3
• /
• pp.301-311
• /
• 2009

Statement of problem: Flapless implant surgery using a soft tissue punch device requires a circumferential excision of the mucosa at the implant site. To date, Although there have been several reports on clinical outcomes of flapless implant surgeries, there are no published reports that address the appropriate size of the soft tissue punch for peri-implant tissue healing. Purpose: In an attempt to help produce guidelines for the use of soft tissue punches, this animal study was undertaken to examine the effect of soft tissue punch size on the healing of peri-implant tissue in a canine mandible model. Material and methods: Bilateral, edentulated, flat alveolar ridges were created in the mandibles of six mongrel dogs. After a three month healing period, three fixtures (diameter, 4.0 mm) were placed on each side of the mandible using 3 mm, 4 mm, or 5 mm soft tissue punches. During subsequent healing periods, the peri-implant mucosa was evaluated using clinical, radiological, and histometric parameters, which included Gingival Index, bleeding on probing, probing pocket depth, marginal bone loss, and vertical dimension measurements of the peri-implant tissues. Results: The results showed significant differences (P <0.05) between the 3 mm, 4 mm and 5 mm tissue punch groups for the length of the junctional epithelium, probing depth, and marginal bone loss during healing periods after implant placement. When the mucosa was punched with a 3 mm tissue punch, the length of the junctional epithelium was shorter, the probing depth was shallower, and less crestal bone loss occurred than when using a tissue punch with a diameter $\geq$ 4 mm. Conclusion: Within the limit of this study, the size of the soft tissue punch plays an important role in achieving optimal healing. Our findings support the use of tissue punch that 1 mm smaller than implant itself to obtain better peri-implant tissue healing around flapless implants.

• Radiation Oncology Journal
• /
• v.14 no.1
• /
• pp.25-31
• /
• 1996

Purpose : To evaluate the potential advantage for 'sandwich' technique radiotherapy compared to Postoperative radiotherapy in resectable rectal cancer. Materials and Methods : Between January 1989 and Mar 1994, 60 patients with resectable rectal cancer were treated at Inje University Seoul and Sanggye Paik Hospital. Fifty one patients were available for analysis: 20 patients were treated with sandwich technique radiotherapy and 31 patients were treated with Postoperative radiotherapy. In sandwich technique radiotherapy(RT), Patients were treated with preoperative RT 1500 cGy/5fx, followed by immediate curative resection. Patients staged as Astler-Coiler B2, C were considered for postoperative RT with 2500-4500 cGy. in postoperative RT total radiation dose of 4500-6120 cGy, 180 cGy daily at 4-Sweets was delivered. Patients were followed for median period of 25 months. Results : The overall 5-year survival rates for sandwich RT group and postoperative RT group were $60\%$ and $71\%$, respectively(p>0.05). The 5-rear disease free survival rates for each group were $63\%$. There was no difference in local failure rate between two groups($11\%$ versus $7\%$) Incidence of distant metastasis was $11\%$(2/20) in the sandwich technique RT group and $20\%$(6/31) in the postoperative RT group(p>0.05). The frequencies of acute and chronic complications were comparable in both groups. Conclusion : The sandwich technique radiotherapy group shows local recurrence and survival similar to those of Postoperative RT alone group but reduced distant metastasis compared to Postoperative RT group. But long term follow-up and large number of patients is needed to make an any firm conclusion regarding the value of this sandwich technique RT.

• Clinical and Experimental Pediatrics
• /
• v.50 no.6
• /
• pp.556-564
• /
• 2007

Purpose : We hypothesized that the persisting bronchial hyperresponsiveness (BHR) of adolescents with asthma remission may be controlled mainly by genetic factors, and the BHR of symptomatic asthma by airway inflammation. ${\beta}_2$-adrenoceptor gene is considered to be a candidate gene in the development of BHR. Thus, ${\beta}_2$-adrenoceptor gene polymorphism may be associated with the BHR of adolescents with asthma remission, but not with the BHR of symptomatic asthma. To evaluate this hypothesis, ${\beta}_2$-adrenoceptor gene polymorphism at 2 sites (Arg16-Gly, Gln27-Glu) were examined. Methods : Two hundred two adolescents with BHR ($PC_{20}<18\;mg/mL$) and long term remission (neither asthma-related symptoms nor medication during the previous 2 years) of their asthma (remission group), 182 adolescents with symptomatic asthma (symptomatic group), and 200 healthy adolescents (control group) were studied. Asthma phenotypes were determined using methacholine bronchial provocation test and skin prick test. Genotypes of ${\beta}_2$-adrenoceptor polymorphism were evaluated by PCR-based methods. Results : Gly/Gly allele and Gly16-Gln27 haplotype were more prevalent in the remission group than in the control group (P=0.01, P=0.02), although there was no difference between the symptomatic group and the control group. In the remission group, there was significant difference in geometric mean of $PC_{20}$ among the 3 groups subdivided by the number of Gly16-Gln27 haplotype, showing that the Gly16-Gln27 haplotype was positively associated with BHR. However, no association was found between Gly16-Gln27 haplotype and BHR in the symptomatic group. Conclusion : This study demonstrates that ${\beta}_2$-adrenoceptor polymorphism at amino acid 16 and 27 was associated with BHR persisting in adolescents with asthma remission.

• Childhood Kidney Diseases
• /
• v.3 no.2
• /
• pp.209-216
• /
• 1999

Purpose : Nephrogenic diabetes insipidus (NDI) is a rare X-linked disorder associated with renal tubule resistance to arginine vasopressin (AVP). The hypothesis that the defect underlying NDI might be a dysfunctional renal AVPR2 has recently been proven by the identification of mutations in the AVPR2 gene in NDT patients. To investigate the association of mutations in th AVPR2 gene with NDI, we analyzed the AVPR2 gene located on the X chromosome. Methods : We have analyzed the AVPR2 gene in a kindred with X-linked NDI. The proband and proband's mother were analyzed by polymerase chain reaction-single strand conformational polymorphism(PCR-SSCP) and DNA sequencing of the AVPR2 gene. We also have used restriction enzyme analysis of genomic PCR product to evaluate the AVPR2 gene. Results : C to T transition at codon 202, predictive of an exchange of tryptophan 202 by cysteine(R202C) in the third extracellular domain was identified. This mutation causes a loss of Hae III site within the gene. Conclusion : We found a R202C missense mutation in the AVPR2 gene causing X-linked NDI, and now direct mutational analysis is available for carrier screening and early diagnosis.