• Journal of the Korean Institute of Gas
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• v.15 no.4
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• pp.1-6
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• 2011

Risk-based inspection (RBI) is a inspection technique suggesting inspection plan, such as inspection interval and inspection method, of the pressurized facilities based on its risk in the petrochemical, refinery and gas industries. Therefore, we can intensively and cost-effectively maintain, repair and manage the high-risk facilities through RBI technology. This paper reviews RBI technology, such as principle and implemental procedure of RBI, management of risks and facilities and return of investment through RBI, RBI technology at present and its application in domestic industries. In addition, some improvement directions of RBI are also proposed.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.534-537
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• 2008

In recent years, the dissimilar metal, Alloy 82/182 welds used to connect stainless steel piping and low alloy steel or carbon steel components in nuclear reactor piping system have experienced cracking due to primary water stress corrosion(PWSCC). It is well known that one reason of the cracking is the residual stress by the weld. But, it is difficult to estimate exactly weld residual stress due to many parameters of welding. In this paper, the analysis of 3 FEM models made by ABAQUS Code is performed to estimate exactly the weld residual stress on the dissimilar metal weld. 3 FEM models are Butt model, Repair model and Overlay model and are the plane.strain 2D model. The thermal analysis and the stress analysis are performed on each model and the residual stresses on each model were calculated and compared respectively. Also, the specimen of Butt model was made and the residual stresses were measured by X-Ray method and Hole Drilling Technique. These results were compared with the FEM result of Butt model.

• Asia-Pacific Journal of Business
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• v.4 no.2
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• pp.31-40
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• 2013

This paper portrays the perception of buying behaviour, factors of product preferences and product switch-over among women consumers in Vellore district of Tamil Nadu. To conduct this study, 300 respondents from 20 village blocks of Vellore district were selected using stratified random sampling as the technique and descriptive sampling as the design. The study came out with interesting results and conclusions. It was found that more than half of the respondents were purchasing the product without a bill. It was also found that the respondents who repaired their product in the authorized service centre during warranty period did not continue the same after the warranty period and preferred nearby repair shops. It was further found that more than half of the respondents were checking expiry date and quality standards while purchasing a product. The study's scope was limited to women consumers at Vellore district. It could be used for further research in other aspects such as gender comparison in Vellore district and comparison with other districts of Tamil Nadu and other states of India. It was suggested that there is still a necessity to upgrade the standard of the people in many aspects like education, occupation and level of income, which shall help them to compete with the neighboring cities on living standards.

• Journal of the Society of Disaster Information
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• v.9 no.4
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• pp.392-399
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• 2013

The use of advanced composite materials in strengthening and repair of existing structures is increasing rapidly. One specific area in which the technique has been introduced lately is the strengthening of metallic structures with bonded carbon-fibre laminates. In this paper, the behaviors of composite steel-CFRP members is studied experimentally. A new type of test specimen has been developed for this purpose. By examining different combination of CFRP-laminates and adhesives, different types of fracture mode could be examined. The tested composite elements also displayed different behavior and a large difference in strength and ductility could be observed.

• The Journal of Korean Physical Therapy
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• v.21 no.4
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• pp.97-102
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• 2009

Purpose: The purpose of this study was to investigate the effects of low intensity pulsed ultrasound on TGF-$\beta$1 expression and healing of rat femur penetrating fractures. Methods: Rats were anesthetized with ketamine and xylazine. Using aseptic technique, we exposed the lateral right femoral diaphysis with removal of the periosteum. We made one hole along its long axis with an electrically-driven 1.8 mm diameter drill bit. Postoperatively, rats were divided into two groups (a control group, n=15; an experimental group, n=15). The experimental group was treated with low intensity pulsed ultrasound (pulse rate: 1:4, 0.5 W/$cm^2$, 10 minutes, 1 time per day) for 3 weeks. The control group was treated with sham ultrasound (with the US unit turned off). Results: The experimental group achieved more callus formation and TGF-$\beta$1 expression than the control group at the $7^{th}$, $14^{th}$ and $21^{st}$ days after low intensity pulsed ultrasound treatment. Conclusion: This study suggests that low intensity pulsed ultrasound facilitates bone fracture repair, possibly via increased TGF-$\beta$1 expression.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.9-15
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• 1998

The strength and stiffness of structures would be weakened by thermal degradation of wood members which are exposed to a variety of heat including a fire. For this reason, thermal degraded wood members can't pertinently support the load. However, it is easy to repair or rehabilitate wood structures. So, the degraded wood members which can't support the load can be replaced with new members. For the sake of this advantage, there is a need for nondestructive evaluation(NDE) technique, which is very effective to assess wood members in service. In this paper, it was considered whether the stress wave method is adequate to estimate static bending MOE of thermal degraded wood. As the result, the relationship between static bending MOE and MOEsw in elevated temperature was found out significant. Therefore, the application of stress wave method for estimating static bending MOE of thermal degraded zzwood would be possible. However, it is thought that further research for the effects of exposure temperature, time, and thermal degradation on the relationship between static bending MOEb and MOEsw would be needed.

• Journal of Chest Surgery
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• v.19 no.3
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• pp.363-373
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• 1986

Even though the pathogenesis is still controversial, electrocardiographic changes after congenital open heart surgery depend on various etiologic factors. Author reviewed 261 cases of congenital open heart surgery patient experienced in the Dept. of Thoracic & Cardiovascular Surgery, Pusan National University Hospital, since July, 1981 to Sept., 1985. The results were summarized as followed: 1. The age distribution was from 3 to 29 years old with mean age 10.8 years. And the most frequent congenital heart defect we had done operation was VSD. 2. Preoperatively, the most frequent ECG finding was abnormal QRS complex and postoperatively the most frequent ECG change was arrhythmia. 3. The most frequent arrhythmia before operation was intraventricular conduction disturbance. 4. Right ventriculotomy incision produced the more frequent abnormal ECG changes postoperatively than right atriotomy or pulmonary arteriotomy. 5. According to the operative technique, outflow patch graft of TOF repair produced the highest frequency of ECG changes after operation, and in comparing simple and patch closure of VSD, the latter was higher frequency of ECG changes, in valvotomy and infundibulectomy of PS, the latter was higher too. 6. The common symptom and signs in abnormally ECG changed patients after operation were palpitation, dyspnea, congestive heart failure and murmur in this order., 7. The longer the time of CPB, the more number of abnormally ECG changed patients had been developed after operation. 8. The most of postoperative ECG changed patients recovered spontaneously or with only medication and were clinically insignificant. And the rest other minor group recovered with temporary pacing. Eight cases out of 261 [3.1%], these with abnormal QRS complex and arrhythmia couldn`t recover in spite of every effort and eventually succumbed.

• Journal of Sensor Science and Technology
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• v.9 no.1
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• pp.76-82
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• 2000

PTC thermistors with multilayer structure were fabricated by internal electrode bonding technique in order to realize low resistance. MLPTC (Multilayer Positive Temperature Coefficient) possess various features, such as small size, low resistivity and large current. We describe the effect of additives on the PTC characteristics, voltage - current characteristics, temperature dependence of resistance and complex impedance spectra as a function of frequency range 100 Hz to 13MHz to determine grain boundary resistance. It was found that MLPTC thermistor has both highly nonlinear effects of temperature dependent resistance and voltage dependent current behaviors, which act as passive element with self-repair mechanisms. Decrease of room temperature resistance with increasing the number of layers was demonstrated to be a grain boundary effect. Switching characteristics of current were caused by heat capacity of PTC thermistor with multilayer structure. Switching times are lengthened by increasing the number of layers.

• Journal of Korean Foot and Ankle Society
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• v.23 no.4
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• pp.143-148
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• 2019

Although many patients who undergo bunion repair do well and have satisfactory results, a critical evaluation of these results shows the potential for improvement. Metatarsal deformity of the hallux valgus is a 3-dimensional deformity, including rotation in the coronal plane. Theoretically, it is important to understand the 3-dimensional displacement of the first metatarsal for correcting the deformities of valgus rotation in the frontal plane. Yet the current methods of metatarsal osteotomy principally attempt to correct the deformity in the transverse plane. The modified technique for the Lapidus procedure can be used in a variety of hallux valgus conditions and severities, and the early results suggest that a powerful correction can be maintained. In addition, efforts have been made to correct the 3-dimensional deformity by performing metatarsal shaft osteotomy. In the case of degenerative arthritis, first metatarsophalangeal joint arthrodesis is a good option to correct the 3-dimensional deformation. Correction of the 3-dimensional deformity, including a rotational deformity in the frontal plane of the metatarsals, should be considered when selecting surgical treatment and is essential for achieving a good prognosis for patients with hallux valgus. This article reviews the classification and treatment of hallux valgus for correction of the 3-dimensional deformity.

• Structural Engineering and Mechanics
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• v.54 no.3
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• pp.521-543
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• 2015

Depending on the damage type as well as the level of damage observed after the earthquake, certain measures should be taken for the damaged buildings. In this study, structural repairing of two different types of damaged RC beam-column assembly by carbon fiber-reinforced polymer sheets is investigated in detail as a member repairing technique. Two types of 1:1 scale test specimens, which represent the exterior RC beam-column connection taken from inflection points of the frame, are utilized. The first specimen is designed according to the current Turkish Earthquake Code, whereas the second one represents a deficient RC beam-column assembly. Both of the specimens were subjected to cyclic quasistatic loading in the laboratory and different levels of structural damage were observed. The first specimen displayed a ductile response with the damage concentrated in the beam. However, in the second specimen, the beam-column joint was severely damaged while the rest of the members did not attain their capacities. Depending on the damage type of the specimens, the damaged members were repaired by CFRP wrapping with different configurations. After testing the repaired specimens, it is found that former capacities of the damaged members were mostly recovered by the application of CFRPs on the damaged members.