• Journal of the Computational Structural Engineering Institute of Korea
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• v.16 no.4
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• pp.353-367
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• 2003

This paper describes the extension of the numerical model, which was developed to simulate the nonlinear behavior of reinforced concrete (RC) structures subjected to monotonic in plane shear and introduced in the companion paper, to simulate effectively the behavior of RE structures under cyclic loadings. While maintaining all the basic assumptions adopted in defining the constitutive relations of concrete under monotonic loadings, a hysteretic stress strain relation of concrete, which across the tension compression region, is defined. In addition, unlike previous simplified stress strain relations, curved unloading and reloading branches inferred from the stress strain relation of steel considering the Bauschinger effect we used. The modifications of the stress strain relation of steel are also introduced to reflect pinching effect depending on the shear span ratio and an average stress distribution in a cracked RC element. Finally, correlation studies between analytical results and experimental studies are conducted to establish the validity of the proposed model.

• Journal of Technologic Dentistry
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• v.35 no.4
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• pp.303-312
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• 2013

Purpose: In this research, non-linear three dimensional finite element models with contact elements were constructed. For the investigations of the distributions of contact stresses, 3 units fixed partial dentures model were studied, especially on the interface of the gold screw and cylinder, abutment screw. Methods: 3 types of models were constructed ; the basic fixed partial denture in molar region with 3 units and 3 implants, the intermediate pontic fixed partial denture model with 3 units and 2 implants, and the extension pontic fixed partial denture model with 3 units and 2 implants. For all types, the external loading due to chewing was simulated by applying $45^{\circ}$ linguo-buccal loading of 300 N to the medial crown. For the simulation of the clamping force which clinically occurs due to the torque, thermal expansion was provided to the cylinder as a preload. Results: Under 300 N concentrated loading to the medial crown, the maximum contact stress between abutment screw and gold screw was 86.85~175.86MPa without preload, while the maximum contact stress on the same area was 25.59~57.84MPa with preload. Conclusion: The preloading affected the outcomes of the finite element stress analysis. Reflecting the clinical conditions, the preloading conditions should be considered for other practical study utilizing FEA. For the study of the contact stresses and related motions, various conditions, such as frictional coefficient changes, gap between contact surfaces, were also varied and analyzed.

• Journal of Intelligence and Information Systems
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• v.8 no.2
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• pp.177-187
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• 2002

Spatial data mining is a process to discover interesting relationships and characteristics those exist implicitly in a spatial database. Many spatial clustering algorithms have been developed. But, there are few approaches that focus simultaneously on clustering spatial data and assigning weight to non-spatial attributes of objects. In this paper, we propose a new spatial clustering algorithm, called DBSCAN-W, which is an extension of the existing density-based clustering algorithm DBSCAN. DBSCAN algorithm considers only the location of objects for clustering objects, whereas DBSCAN-W considers not only the location of each object but also its non-spatial attributes relevant to a given application. In DBSCAN-W, each datum has a region represented as a circle of various radius, where the radius means the degree of the importance of the object in the application. We showed that DBSCAN-W is effective in generating clusters reflecting the users requirements through experiments.

• The Journal of Korean Society for School & Community Health Education
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• v.15 no.1
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• pp.77-87
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• 2014

Objectives: The Purpose of this study was to investigate the effects of chiropractic treatment and low back exercise on lumbar lordosis angle, gravity line, range of motion, and pain degree of university students who are taking a commuter bus at least 4 hours of round trip. Methods: A group of 15 participants received chiropractic treatment around the lumbar spine region twice per week for 8 weeks. Another group of 15 participants were treated with low back exercise three times per week for 8 weeks. Results: In the present results, both chiropractic treatment and low back exercise did not affect the change of lumbar lordosis. However, chiropractic treatment also significantly improved the range of the lumbar motion, including Flexion, Extension, Right Lateral Flexion and Left Lateral Flexion(p<0.05), and consequently decreased the pain degree. Low back exercise significantly moved the lumbar gravity line to almost normal scale, and improved the range of the lumbar motion, including Flexion, and Right Lateral Flexion (p<0.05), resulting in the reduction of pain degree, although both chiropractic treatment and exercise treatment did not change the lumbar lordosis angle at the statistically significant. Conclusions: From these results, it can be inferred that chiropractic treatment might be beneficial to alleviating the low back pain of the university students using a commuter bus by improving the range of lumbar motion or stabilizing the lumbar gravity line.

• The Plant Pathology Journal
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• v.21 no.4
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• pp.349-354
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• 2005

A virus isolate collected from infected paprika (Capsicum annuum var. grossum) was characterized as Potato virus Y (PVY) based on biological, serological, cytopathological, and molecular properties. In host range studies, the paprika isolate produced the mosaic symptom on some tobacco, tomato and pepper (Capsicum annuum). A new paprika isolate also infected potato cultivars which is different biological characteristic compared to the other popular potyvirus infecting paprika, Pepper mottle virus (PepMoV). Previously reported PVY strains, $PVY^o$ and $PVY^N$ did not infect pepper and typical PepMoV isolates did not infect potato. Distinctive inclusion patterns of the scroll, pinwheel, long laminated inclusions, and helper components in the cytoplasm of infected cells were also different to those observed by the typical PVY isolate infections. However, the paprika isolate reacted to the monoclonal antibody of $PVY^N$ strain with high absorbance readings. RT-PCR amplification, cloning, and sequencing of the 3' untranslated region and a part of coat protein gene also added additional evidence of the paprika isolate as the $PVY^N$-related isolate. Multiple alignments as well as cluster dendrograms of PVY-paprika isolate revealed close phylogenetic relationship to the $PVY^N$ subgroup. Altogether, these results suggest that a new PVY isolate infecting paprika contained distinct characteristics compared to the other previously described PVY strains with closer relationship to the $PVY^N$ strain.

• Archives of Plastic Surgery
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• v.34 no.2
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• pp.250-257
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• 2007

Purpose: Aging changes of midface include drooping of lower lid, wrinkles of malar area, orbitomalar groove and deepening of nasolabial fold from drooping of malar fat pad. Improvement of lower lid can be achieved through lower blepharoplasty, but improvement of cheek can not be gained. Superficial subciliary cheek lift(by Moelleken, 1996) is a method that lifts malar fat pad through extended subciliary incision. We obtained simultaneous improvement of lower lid, malar wrinkles and orbitomalar groove with modification of this technique. Methods: From December 2003 to January 2006, we performed this method on 21 patients among volunteers for lower blepharoplasty who wanted to correct orbitomalar groove and malar wrinkles. Under local anesthesia, lateral extension of subciliary incision is done 1cm from the lateral orbital rim. Skin-muscle flap is elevated, and dealing of orbital fat and septum is the same as with ordinary lower blepharoplasty. After downward subcutaneous dissection through extended incision, exposing the upper 1/3 level of malar fat pad, superolateral fixation is done to superior deep temporal fascia. Excision of the upper part of fat pad is performed, if needed. After excision of overlapped skin-muscle flap, skin closure is done. Results: We obtained satisfactory results with this simple method for improvement of orbitomalar groove and malar wrinkles among patients for lower blepharoplasty. During a follow-up period of 5 months on the average, no revision was performed. Conclusion: Under local anesthesia, lower blepharoplasty and improvement of orbitomalar groove and malar wrinkles can be achieved at the same time. It is good for patients who do not want conventional midface-lifting. But surgeons should select patients and perform cautiously for it may leave a scar of the extended incision that require over 2 months for maturation and it is insufficient for improvement of nasolabial fold compared to conventional mid face-lifts.

• Journal of Korean Society of Transportation
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• v.28 no.2
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• pp.33-43
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• 2010

The objective of this paper is to analyze expenditure structures and impact factors of household's transportation cost in order to provide policy-maker with quantitative and economic information for reducing household's transportation costs, using 1995-2007 household survey data. For this purpose, this study performed various economic analysis, including econometric regression analysis and income re-distributional effects. The four models were separately estimated with dependent variable (personal and public costs, public transit and private car costs) and independent variables (family, employ, age, education, cars, household income, region dummy variable). In addition, We analyzes impacts of transport policy instruments on the transportation expenditure. These instruments include changes of oil price and public transit fare, reform of public transport system, and extension of subway facilities. Finally, income re-distributional effects before and after transportation expenditure, using Pechman-Okner (PO) index and Wolfson index.

• Korean Journal of Acupuncture
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• v.27 no.1
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• pp.143-150
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• 2010

Objectives: This research aims to know the current status and prospect of traditional medical market to provide sources in setting a development strategy and making a policy on the traditional medicine Methods: This research categorized 11,611 clinics registered in telephone directory as of 2008 by region and some clinics were extracted with simple random method. The inquiry was made with questionnaires and analyzed on the base of frequency. Results: 1. The number of the employee in a clinic were slightly decreased from 2.9 in 2005 and 2006 to 2.8 in 2007. That of the patients also showed a downward tendency from 11,811 in 2005 through 11,716 in 2006 to 11,344 in 2007. 2. An annual turnover in a clinic amounted to 257 million won in 2007 from 232 million won in 2005 through 245 million won in 2006. 3. Approximately 92% of the responses made a negative diagnosis on the traditional medical market and 21% of responses indicated the overall economic recession as a primary reason in their opinions. 4. About 29% of responses presented the extension of medical insurance on traditional medicine as a prior policy. Conclusions: Based on the survey, the prospect of traditional medical market is positive, but the effort of the people in traditional medical system and the systematic support from government are required to activate the stagnated traditional medical market.

• Advances in Computational Design
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• v.5 no.1
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• pp.1-11
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• 2020

Soil is the fundamental element in the construction process. Soil problems affect the safety of the structures, even so the high quality of the structures and so, bad soil found the structures will affect the lifetime or even destroy the structures built on it. Therefore, the study of soil is an important step in the construction process and the investigation of the most effective characteristics of a special kind of soil (shale soil), i.e. Atterberg limits, swelling pressure, swelling potential and unconfined compression strength, are the most effective soil properties. A big projects will be constructed in new urban extension areas with expansive shale soils, like at Al-Kawamil and new Akhmim shale soils which associated with soil problems, treatment system should be used to ensure the stability of the soil under the structures foundations one of the most effective methods is by adding lime solution to the soil by specific quantities, which affect on the properties of the shale soil by decreasing the swelling and increasing the compressive strength of the treatment soils. Experimenting with the soil added to the lime, it was found that the addition of lime solution 6% improve c j the properties of the soil. The results of the tests showed the high effectiveness of using lime in the treatment of Al-Kawamil soil

• Korean Journal of Remote Sensing
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• v.25 no.5
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• pp.455-464
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• 2009

Lee(2009) proposed the boundary-adaptive despeckling method using a Bayesian model which is based on the lognormal distribution for image intensity and a Markov random field(MRF) for image texture. This method employs the Point-Jacobian iteration to obtain a maximum a posteriori(MAP) estimate of despeckled imagery. The boundary-adaptive algorithm is designed to use less information from more distant neighbors as the pixel is closer to boundary. It can reduce the possibility to involve the pixel values of adjacent region with different characteristics. The boundary-adaptive scheme was comprehensively evaluated using simulation data and the effectiveness of boundary adaption was proved in Lee(2009). This study, as an extension of Lee(2009), has suggested a modified iteration algorithm of MAP estimation to enhance computational efficiency and to combine classification. The experiment of simulation data shows that the boundary-adaption results in yielding clear boundary as well as reducing error in classification. The boundary-adaptive scheme has also been applied to high resolution Terra-SAR data acquired from the west coast of Youngjong-do, and the results imply that it can improve analytical accuracy in SAR application.