• Title/Summary/Keyword: 손상원인

Search Result 1,049, Processing Time 0.036 seconds

An Analysis of Best Practices for Efficient Utility Relocation and an Inquiry into the Applicability of SUE (효율적인 지하지장물 이설을 위한 모범사례분석 및 SUE 적용에 관한 연구)

  • Lee, Seung-Hyun;Baek, Seung-Ho;Tae, Yong-Ho;Ahn, Bang-Ryul;Park, Hyeon-Yong
    • Proceedings of the Korean Institute Of Construction Engineering and Management
    • /
    • 2007.11a
    • /
    • pp.971-976
    • /
    • 2007
  • In the U.S., utility damages or utility delay caused by conflicts during the underground utility relocation is one of the weighty problem in the construction industry. Also, in domestic case, delay and additional cost caused by underground utility(i.e, electricity, communication, gas, water supply and sewerage) relocation has been happened so that there is an increase of claims for responsibility between owners and contractors. However, there is insufficient survey for the recent circumstance of additional cost for delay and design changes caused by utility relocation and shortage of enough research for solving and analyzing of causes and their ripple effect. This research presents a result of the study about the best practices of FHWA(Federal Highway Administration), SHAs(State Highway Agencies) and the utility companies managing utility relocation. Also, it presents the basic concept of SUE(Subsurface Utility Engineering), the most reliable tool of FHWA presented, and investigates the developing status about SUE in Korea. At the end of this paper, this research proposes a practical and more applicable study about the efficient utility relocation focusing on local industry.

  • PDF

Enhancement of Antioxidation Effect of Platycodon grandiflorum with Vitamin C on the DLPC Liposomes (DLPC Liposome에 미치는 도라지 추출성분의 비타민 C 첨가에 의한 항산화력 상승효과)

  • 배송자;강보영;김미향
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.31 no.3
    • /
    • pp.506-510
    • /
    • 2002
  • The effect of antioxidant activity of Platycodon grandiflorum (PG) on the liposomal phospholipid membrane was investigated by spectrophotometry. Membrane oxidation causes damage to the membrane fluidity and permeability. It brings further destruction to the sustenance of biological homeostasis. In addition, it is related to several diseases, aging and carcinogenesis. The sample PG was extracted and fractionated to five different types; butanol (PGMB), ethylacetate (PGMEA), ethylether (PGMEE), hexane (PGMH) and methanol (PGMM). The oxidation indices of PGMEA and PGMEE fractions in oxidized dilinoleoylphosphatidylcholine (DLPC) liposomes had stronger antioxidant activities than that of ${\alpha}$-tocopherol and were similar to antioxidant activities compared with butylated hydroxy toluene (BHT), a well-known potent antioxidant, in oxidized DLPC liposomes. The oxidation indices of PGMM extract, PGMB and PGMH fractions exhibited weak antioxidant activity compared with ${\alpha}$-tocopherol in oxidized DLPC liposomes. The oxidation indiex of PGMEE fractions added with vitamin C showed even strong antioxidant activity in the oxidized DLPC liposomes. The oxidation activity of BHT with vitamin C also proved to be stronger than BHT without vitamin C. Therefore vitamin C evidently helps to improve the effect of antioxidant in DLPC liposomes. These results indicate that potentially bioactive substances in PGMEE fraction has a function as potent antioxidant against phospholipid membrane oxidation.

A Study on the Resistance of Stress Corrosion Cracking due to Expansion Methods for Steam Generator Tubes in Nuclear Power Plants (원전 증기발생기 전열관의 확관방법에 따른 응력부식균열 저항성 연구)

  • Kim, Young Kyu;Song, Myung Ho
    • Journal of Energy Engineering
    • /
    • v.23 no.2
    • /
    • pp.149-157
    • /
    • 2014
  • The steam generator tubes of nuclear power plants have various types of corrosion failures during the plant operation. The stress corrosion cracking which occurs on the outer surface of tube is called the secondary side stress corrosion cracking and mainly occurs in the expansion-transition area of tube. The causes are the concentration of impurities by the sludge pile-up related to the geometry of its region and the residual stress by tube expansion in the process of steam generator manufacturing. Especially the directionality and sizes of residual stresses are differed according to the tube expansion methods and the direction and the frequency of tube cracks depend on their characteristics. In bases on the plant experiences, it is notified that circumferential cracks of tubes expanded with explosive expansion method are dominantly occurred compared to those of tubes done with hydraulic expansion one. Therefore in this study, according to tube expansion methods frequencies and sizes of tube cracks with specific direction are compared by means of accelerated immersion test and also the crack morphology and the specific chemicals from water-chemistry environment are observed through the fracture surface examination.

Arthroscopic Management in the Athletic Elbow Lesion (주관절 병변이 있는 운동 선수에서 관절경적 처치)

  • Moon Young Lae;Ha Sang Ho;You Jae Won;Joo Jeong Yong;Kim Dong Hui
    • Journal of Korean Orthopaedic Sports Medicine
    • /
    • v.1 no.1
    • /
    • pp.97-101
    • /
    • 2002
  • Purpose : To describe clinical results and improvement of range of motion and pain after arthroscopic treatment for the athletic elbow lesion. Materials and Methods : We reviewed 13 cases of functional restriction of the elbow motion, who all patients were treated by conservative treatment during than 6 months but failed. We performed arthroscopic osteophytectomy, capsular release, spur excision. The interval from injury to operation was average of 13 months (range, eight to sixteen months). We used the Broberg and Morrey functional rating score system in evaluating result. The follow-up period averaged 6 months. Results : Arthroscopic finding that moderative to severe synovitis in all cases, intraarticular loose body in 9 cases, olecranon bony spur in 2 cases, was observed. All cases were successfully improved in range of motion and pain without in any further operation. Preoperative average score was 65 and postoperative average score was 89.4 in Broberg and Morrey functional rating score. Conclusions : Arthroscopic treatment appear to be satisfactory management modality due to diagnose the casative factor and reduce the injury around the elbow joint in painful elbow lesion. Elbow arthroscopy appears to be a safe and effective treatment for athletes, allowing easy return to participation in sports.

  • PDF

Assessment of Systemic Arterial Thromboembolism with Multi-Slice Spiral CT in a Dog (개에서 다중나선형 CT촬영에 의한 동맥혈전색전증의 평가)

  • Shin, Seung-Ho;Lee, Ki-Chang
    • Journal of Veterinary Clinics
    • /
    • v.24 no.2
    • /
    • pp.208-213
    • /
    • 2007
  • A 15 kg 6-year-old intact male Jindo dog with a history of a respiratory distress, hindlimb paralysis with necrosed skin of dorsal digit for three weeks was referred to Animal Medical Center, Chonbuk National University. Heartworm infection was identified by kit examination. In plain thoracic radiographs, dilated pulmonary arteries reverse D sign and focal interstitial pattern was compatible with heartworm infection and possible pulmonary thromboembolism. Abdominal radiographs showed poor serosal detail indicating fluid accumulation within peritoneal cavity. No evidence of musculoskeletal abnormalities was found. Ultrasonography presented focal wedge-shaped hyperechogenecity on the both poles of left kidney, weak or absent pulse on the distal to the external iliac artery as well as ascites and irregular liver margin. Multi-organ failure was strongly supposed by blood profile including leukocytosis, anemia, hemoglobinuria bililubinemia, hypoalbuminemia, imbalance of electrolytes, and increased hepatic and renal function values. Interestingly, the glucose level is remarkably lower in pelvic limb compared to thoracic limb. Suspected pulmonary thromboembolism, renal infarction and femoral arterial embolization causing hindlimb paralysis and dermatic necrosis were confirmed by 3D reconstructed CT imaging. Prior to taking a consideration of euthanasia, interventional radiology was experimentally attempted but failed due to not recovered from general anesthesia. Early and accurate diagnosis of thromboembolism is valuable and 3D reconstructed CT images might be very useful to show the correct way to treat effectively.

A Study for a Near-Field Microwave Microscope Using a Tuning Fork Distance Control System in liquid Environment (튜닝폭 거리조절 센서를 이용한 근접장 마이크로파 현미경의 수중 측정을 위한 연구)

  • Kim, Song-Hui;Yoo, Hyung-Keun;Babajanyan, Arsen;Kim, Jong-Chul;Lee, Kie-Jin
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.27 no.4
    • /
    • pp.345-353
    • /
    • 2007
  • We have obtained a topographical image nondestructively for a Cu thin film in liquid using a near-field scanning microwave microscope (NSMM), its operating frequency was 3.5 to 5.5 GHz. We have kept a distance of 10 nm between tip and sample using a quartz tuning fork shear force feedback system. As an end of tip was attached to one prong of the quartz tuning fork has a length of 2 mm, the only tip of tuning fork was immersed in water tank. A loss cause by evaporation in water tank is regulated with actuator was connected to a supplementary tank. Moreover, using a revise program of LabView, we could increase the accuracy of a measurement in liquid.

The Effects of Panax Ginseng Extract on Antioxidative Enzyme Activity in Ovariectomized Rats (인삼 추출물이 난소를 절제한 백서의 항산화효소 활성에 미치는 영향)

  • 하배진;황일영
    • Journal of Life Science
    • /
    • v.12 no.3
    • /
    • pp.349-356
    • /
    • 2002
  • In order to observe the bioactivity of ovariectomized rats, nonovariertoized (sham) group, ovariectomized (Ovx) group, ovariectomized ginseng total saponin (GTS)-treated (Ovx+ GTS) group and ovariectomized ginseng water extract (GW)-treated (Ovx+CW) group were made. We measured AST (L-aspartate aminotransferase) and ALT (L-alanin aminotransferase) in sera, and MDA (malondialdehyde:lipid peroxidation), SOD (superoxide dismutase), catalase, total-glutathione (GSH + GSSG) and GPx (glutathione peroxidase) in liver tissue total homogenates of rat. AST activity of serum in Ovx group was 2.11 times increased, but ALT activity was not changed compared to Sham group. In AST activity, they tend to decrease significantly in each substance such as GTS and GW administered group. Lipidperoxides of each fraction in Ovx group were highly increased compared to Sham group. Extracts of ginseng-treated group markedly inhibited lipid peroxidation by 62% ∼72%. And as the result of the measurements of SOD, catalase, total-glutathione and GPx which are antioxidant enzyme, antioxidant enzymes in Ovx group much lower than in Sham group. But they were significantly increased in each substance such as GTS and GW, administered group. Based on the results, it is supposed that more produced free radicals decreased antioxidant enzyme. And it is also thought that extracts of ginseng can inhibit aging by reducing antioxidant enzyme.

Mass Mortalities of Cultured Striped Beakperch, Oplegnathus fasciatus by Iridoviral Infection (이리도 바이러스 감염에 의한 양식 돌돔, Oplegnathus fasciatus의 대량폐사)

  • Sohn, Sang-Gyu;Choi, Dong-Lim;Do, Jeung-Wan;Hwang, Jee-Youn;Park, Jeong-Woo
    • Journal of fish pathology
    • /
    • v.13 no.2
    • /
    • pp.121-127
    • /
    • 2000
  • From August to October 1998, over 60% mortality of cultured striped beakperch Oplegnathus fasciatus was occurred in net cages along the southern coast of Korea. Moribund fish showed some clinical signs of lethargic behavior, dark coloration or decoloration, severe gill anemia and enlargement of spleen. Also enlarged basophilic cells showing Feulgen -positive reaction were observed in the tissue section of spleen, kidney, liver and heart of the diseased fish. GF cells inoculated with spleen homogenate of diseased fish produced cytopathic effect of enlarged and rounded cells, therefore the causative virus was isolated from diseased fish. Striped beakperch fingerlings intraperitoneally inoculated with the causative virus ($10^4TCID_{50}$/0.1 ml) revealed symptoms similar to those of naturally infected fish and died from 7 to 14 days post injection. Transmission electron microscopy revealed that the causative virus was enveloped icosahedral particle with 120~130 nm in diameter. PCR products of the expected size (500 bp) were amplified with a primer set based on the ATPase gene of RSIV(red sea bream iridovirus) using template DNAs which were extracted from the spleen of diseased fish and GF cells inoculated with the causative virus. According to the analysis of nucleotide sequence of these PCR products, the sequence from ATPase cDNA gene of the causative virus showed 95% homology with that of RSIV. These results indicate that the mass mortality in the cultured striped beakperch was caused by the infection of iridovirus similar to RSIV.

  • PDF

Oil Fence Durability Enhancement for Marine Environmental Protection : Improvement of Inspection Process (해양환경 보호를 위한 오일펜스의 내구성 향상 : 검정제도 개선 방향)

  • Jang, Pankil;Seo, Jeong Mog;Lee, Heejin
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.27 no.6
    • /
    • pp.731-736
    • /
    • 2021
  • Oil fences effectively prevent the spread of oil spilled in the sea, thereby reducing the damage to the marine environment. However, the fence is damaged by oil and structures at the accident site and is discarded. When incinerated disposal method for discarded fences, fine dust, and harmful materials are generated. Moreover, as a part of the damaged fence is dumped into the sea, it may cause secondary environmental pollution, such as microplastics. Therefore, in this study, durability was measured using the most common solid foam type oil fences. As a result, the reduction rate of after five days of contact was 13 % in seawater and 3 % in oil, affected by temperature changes. Thus, the durability of the fence should be improved because it is exposed to seawater and oil and affected by wind, light, and waves depending on the weather conditions. Therefore, we suggest a method to improve the oil fence inspection to strengthen the durability of the fence's fabric part.

Structural Integrity Assessment of Helicopter Composite Rotor Blade by Analyzing Bird-strike Resistance (조류충돌 해석을 통한 헬리콥터 복합재 로터 블레이드 구조 건전성 평가)

  • Park, Jehong;Jang, Jun Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.8
    • /
    • pp.8-14
    • /
    • 2019
  • Bird-strike is one of the most important design factors for safety in the aviation industry. Bird-strikes have been the cause of significant damage to aircraft and rotorcraft structures and the loss of life. This study used DYTRAN software to simulate the transient response of an Euler-Lagrangian composite helicopter blade that has been impacted by a bird. The Arbitrary Lagrangian Eulerian (ALE) method and a suitable equation of state were applied to model the bird. ALE was applied to the bird-strike analysis due to the large difference between the properties of the blade and bird. The debris of the bird was assumed to be a fluid and applied as Euler elements after the collision. Through the analysis of bird impacts, the leading-edge of the rotor blade (50.8 mm) was used to identify a positive margin of 1.18 based on the TSAI-FILL criteria. The results are assessed to be sufficiently reliable and may be evaluated to replace tests with various analysis conditions. The structural stability of the rotor blade could be assessed by applying various load conditions and different modeling methods in the future.