• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2223-2233
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• 1993

An engineering method is suggested to calculate the applied load versus crack extension in the elastic-plastic fracture. The condition for an increment of crack extension is set by a critical increment of crack-up opening displacement(CTOD). The ratio of the CTOD increment to the incremental crack extention is a critical crack-tip opening angle(CTOA), assumed to be constant for a material of a given thickness. The Dugdale model of crack-tip deformation in an infinite plate is applied to the method, and a complete solution for crack extension and crack instability is obtained. For finite-size specimens of arbitrary geometry in general yielding, an approximate generalization of the Dugdale model is suggested so that the approximation approaches the small-scale yielding solution in a low applied load and the finite-element solution in a large applied load. Maximum load is calculated so that an applied load attains either a limit load on an unbroken ligament or a peak load during crack extension. The proposed method was applied to three-point bend specimens of a carbon steel SM45C in various sizes. Reasonable agreements are found between calculated maximum loads and experimental failure loads. Therefore, the method can be a viable alternative to the J-R curve approach in the elastic-plastic fracture analysis.

• Archives of Craniofacial Surgery
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• v.11 no.2
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• pp.116-119
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• 2010

Purpose: Arteriovenous fistulas that involve the cavernous sinus often produce ophthalmologic symptoms and signs. Transvenous endovascular access is the method of choice for a carotid-cavernous sinus fistula. The superior ophthalmic vein is a safe and reasonable alternative route for the transvenous embolization of carotid-cavernous sinus fistula. We report a case of the embolization of a carotid-cavernous sinus fistula using the superior ophthalmic vein approach. Methods: A 58 year old female had conjunctival congestion, periocular pain and diplopia with a 2 month duration. Diagnostic orbital CT, brain MRI and cerebral angiography revealed a carotid-cavernous sinus fistula. The fistula occlusion was treated by coil embolization using the superior ophthalmic vein approach. Results: The initial presenting symptoms, conjunctival congestion, periocular pain and diplopia, decreased after surgery. Coil embolization via the superior ophthalmic vein approach was difficult because of the venous tortuosity and friability. During the follow up period, the patient was in a good condition without complications. Conclusion: Surgical exposure of the superior ophthalmic vein provides direct venous access to the cavernous sinus as well as an effective and safe treatment approach. The cooperation of the plastic surgeon and interventionist is a factor in successful treatment.

• Fire Science and Engineering
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• v.14 no.2
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• pp.21-32
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• 2000

In this study, reduced-scale experiments as the alternative to a real-scale fire test were conducted to understand fire properties in tunnel, and their results were compared with those of numerical simulation. The 1/20 scale experiments were conducted under the Froude scaling since smoke movement in tunnel is governed by buoyancy farce. A numerical simulations were on performed 3D unstructured meshes with PISO algorithm and buoyant plume models. Results showed that data was in reasonable agreement with the numerical data of smoke velocity, temperature distribution, and clear height.

• Clinics in Shoulder and Elbow
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• v.1 no.1
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• pp.6-11
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• 1998

Shoulder is a common site for calcific deposit and is frequently asymptomatic. There is a general agreement that calcific tendinitis should be initially treated nonoperatively and excision reserved for cases unresponsive to the conservative measures. There are several reports that arthroscopic excision of symptomatic calcific deposit is proved to be efficient in the calcific tendinitis refractory to nonoperative management. The results of arthroscopic treatment of chronic resistant calcific tendinitis of the shoulder in eleven patients were evaluated. Each patient had shoulder pain for more than one year prior to the arthroscopic surgery. The average age of the patients was 48 years(range 35-70). Arthroscopic calcium removal and subacromial bursectomy was performed in all patients. Arthroscopic acromioplasty was additionally done in four patients. The results turned out to be good in nine patients with full range of motion and complete pain relief. One patient with full motion and occcasional episodes of pain was satisfactory. One patient with persistent pain was unsatisfactory which converted to satisfactory six months later after subacromial injection. So we conclude that the arthroscopic treatment is a reasonable alternative in treatment of the chronic calcific tendinitis resistant to conservative treatment.

• Journal of Soil and Groundwater Environment
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• v.15 no.5
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• pp.32-39
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• 2010

In this study, we applied DRASTIC and SINTACS models for the assessment of groundwater vulnerability to Buyeo-eup area in Buyeo-gun, Chungcheongnam-do, Korea. Currently, DRASTIC model is a main tool for the assessment of groundwater vulnerability, which has been widely applied for the multiple purposes related to local developments, construction projects, groundwater investigations, etc. since 1980s. Because DRASTIC model has been the sole tool used for the domestic environment, there has been doubt about the degree of reliability of the model, and a benchmark model has been sought by the many practitioners. The objective of this study is to check the applicability of SINTACS model to domestic environment, which is the first attempt in Korea as far as authors understand. The comparative results show that the DRASTIC assessment underestimates groundwater vulnerability of the aquifers composed of fractured bedrocks while that from the SINTACS model is relatively higher. Through this study, it is expected that SINTACS model serves as a reasonable alternative of DRASTIC model where the subsurface is composed of more than two different media such as fractured rocks and alluvium.

• Clinical and Experimental Pediatrics
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• v.61 no.1
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• pp.6-11
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• 2018

Purpose: Mid-upper-arm circumference (MUAC) is considered an alternative screening method for obesity. The aims of this investigation were to examine the ability of MUAC to correctly identify children with elevated body mass index (BMI) and to determine the best MUAC cutoff point for identification of children with high BMI. Methods: Anthropometric measurements (height, weight, and MUAC) from a cross-sectional sample of 7,921 Pakistani children aged 5-14 years were analyzed. Pearson correlation coefficients between MUAC and other anthropometric measurements were calculated. Receiver operating characteristic curve analysis was used to determine the optimal MUAC cutoff point for identifying children with high BMI. Results: Among 7,921 children, the mean (${\pm}$standard deviation) age, BMI, and MUAC were 10.00 (${\pm}2.86years$), 16.16 (${\pm}2.66kg/m^2$), and 17.73 (${\pm}2.59cm$), respectively. The MUAC had a strong positive correlation with BMI. The optimal MUAC cutoff points indicating elevated BMI in boys ranged from 16.76 to 22.73, while the corresponding values in girls ranged from 16.38 to 20.57. Conclusion: MUAC may be used as a simple indicator of overweight/obesity in children, with reasonable accuracy in clinical settings.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.8
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• pp.883-890
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• 2005

The industrial growth and the raised living quality have led to the massive energy consumption. As a result. the polluted environment and the limited amount of energy resources emerged as serious problems to be resolved in 21st century. Especially, in the case of Korea whose imported energy dependency rate is 98.2$\%$ in 2003 and constantly increasing every rear. more than 24$\%$ of overall energy consumption is for housing and commercial use. In order to cope with the shortage of natural energy resources, it is inevitable to develop alternative sustainable energy resources including seawater heat. so that they can replace existing resources. The heat transfer air velocity 3.5 m/s is proper to consideration with the body the pipe size 200A is more suitable than look due to the air velocity quantify and the ratio of pipe surface area. And the error between experimental data with simulation is below 5.34$\%$ so the suggested equation for calculating heat transfer capacity can be used. Therefore out of many methods utilizing seawater heat. this work Presents the efficiency of using sea water heat as a resource for air-conditioners which can be converted from the outside air through the air-to-heat conversion tube . Consequently. this method provides pretty reasonable energy efficiency.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.3
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• pp.351-359
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• 2010

Bi-fuel system in a spark ignition engine (SIE) is a rising phenomena in today's automobile technology. In a gasoline driven vehicle, alternatively adoption of compressed natural gas (CNG) could be used as a potential substitute to meet the energy requirement and this is possible by some minor changes in the hardware of the existing engine. Gasoline engine is widely used in the passenger cars, light, medium and heavy duty vehicles but the consumption status of the petroleum is decreasing worldwide and at the same time environmental pollution from automobiles is seriously establishes as a threat for every nation in respect to global warming and climate changes. Now-a-days most vehicles operate using CNG for its popularity stems, clean burning properties and cost effective solution compared to other alternative fuels. It refers as a good gaseous fuel because of its high octane number and self ignition temperature. Though the power output is slightly lesser than the gasoline fuel; its thermal efficiency is better than the gasoline for the same SIE. The research paper highlights the reduction of CO, reasonable outcomes of HC emissions with minor increase in $NO_x$ emissions compared with the gasoline fuel to bi-fuel mode in the SIE that meets the emission challenges.

• Journal of Urban Science
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• v.7 no.1
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• pp.29-38
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• 2018

The cadastral rehabilitation project, which has been implemented since 2012, is a project to re-examine the national land that is not in conformity with the cadastral map, There is a lot of trouble in securing financial resources for business execution. This study examines the utility of UAS(Unmanned Aerial System) image - based cadastral demarcation as an alternative to budget reduction in the current state of cadastral rehabilitation, reasonable boundary adjustment, UAV(Unmanned Aerial Vehicles) is used to create 3D models and orthoimages of business districts, and to check accuracy by superimposing and comparing with digital maps of NGII(National Geographic Information Institute). As a result of the study, the accuracy of the 3D model and the orthoimage through the SfM(Structure-from-Motion) - based image interpretation of the digital map of the NGII were derived. In particular, we confirmed the similarity of UAS-based orthoimage with the cadastral boundaries affirmation, It is anticipated that the cost saving effect of current survey and boundary survey can be expected. In addition, it is easy to prepare a report to reduce civil complaints, which is a problematic element of the adjustment.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.22-26
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• 2007

In this study we had chosen the examples of the development projects, so that examined about the process of the landscape impact assessment and the detail evaluation items. Especially the part of the leisure facilities and the landscape aspects among the evaluation items were reviewed whether followed the process of environment impact assessment or not, whether the impact estimate, and depreciation scheme according to the present condition and enforcement of the actual development projects perform reasonably or not. From the study, derived the improvement on the landscape impact evaluation using with 3D Simulation method is expected to contribute to the valid landscape impact assessment and the reasonable alternative proposal.