• International conference on construction engineering and project management
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• 2013.01a
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• pp.494-496
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• 2013

Cost-Benefit Analysis (CBA) is a systematic optimization process that allows users to compare different alternatives and to determine if a project is a solid investment. Many state DOTs have included CBA in their pavement management systems (PMSs) to help allocate state funds for maintenance, rehabilitation, resurfacing, and reconstruction of pavements. In a typical CBA, each pavement type has an assigned weight factor which represents the level of importance of this pavement type. To conduct an accurate CBA, it is essential to select appropriate weight factors. Arbitrarily assigning weights factors to pavements can lead to biased and inaccurate funding allocation decisions. The purpose for this paper is to outline a method to develop an ideal set of weight factors that can be utilized to conduct more accurate CBA. To this end, a matrix of all possible weight factors sets was developed. CBA was conducted for each set of weight factors to obtain a population of possible optimization solutions. Then a regression analysis was performed to establish the relationship between benefit and weight factors. Finally, a multi-objective genetic algorithm was applied to select the optimal set of weight factors. The findings from this study can be used by state DOTs to strategically manage their roadway systems in a cost effective manner.

• Fibers and Polymers
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• v.7 no.4
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• pp.389-397
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• 2006

The beneficial effects of graduated compression stockings (GCS) in prophylaxis and treatment of venous disorders of human lower extremity have been recognized. However, their pressure functional performances are variable and unstable in practical applications, and the exact mechanisms of action remain controversial. Direct surface pressure measurements and indirect material properties testing are not enough for fully understanding the interaction between stocking and leg. A three dimensional (3D) biomechanical mathematical model for numerically simulating the interaction between leg and GCS in dynamic wear was developed based on the actual geometry of the female leg obtained from 3D reconstruction of MR images and the real size and mechanical properties of the compression stocking prototype. The biomechanical solid leg model consists of bones and soft tissues, and an orthotropic shell model is built for the stocking hose. The dynamic putting-on process is simulated by defining the contact of finite relative sliding between the two objects. The surface pressure magnitude and distribution along the different height levels of the leg and stress profiles of stockings were simulated. As well, their dynamic alterations with time processing were quantitatively analyzed. Through validation, the simulated results showed a reasonable agreement with the experimental measurements, and the simulated pressure gradient distribution from the ankle to the thigh (100:67:30) accorded with the advised criterion by the European committee for standardization. The developed model can be used to predict and visualize the dynamic pressure and stress performances exerted by compression stocking in wear, and to optimize the material mechanical properties in stocking design, thus, helping us understand mechanisms of compression action and improving medical functions of GCS.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.2
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• pp.100-107
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• 2010

Introduction: A cyst is a closed pathologic sac containing fluid or semi-solid material in central region. The most common conventional treatment for a cyst is enucleation. It was reported that spontaneous bone healing could be accomplished without bone grafting. We are trying to evaluate bone reconstruction ability by analyzing panorama radiograph and computed tomography (CT) scan with retrograde studying after cyst enucleation. In this way we are estimating critical size defect for spontaneous healing without bone graft. Materials and Methods: The study comprised of 45 patients who were diagnosed as cysts and implemented enucleation treatment without bone graft. After radiograph photo taking ante and post surgery for 6, 12, 18, 24 months, the healing surface and volumetric changes were calculated. Results: 1. Spontaneous bone healing was accomplished clinically satisfying 12 months later after surgery. But analyzing CT scan, defect volume changes indicate 79.24% which imply incomplete bone healing of defect area. 2. Comparing volume changes of defect area of CT scan, there are statistical significance between under $5,000mm^{3}$ and over $5,000mm^{3}$. The defect volume of $5,000mm^{3}$ shows $2.79{\times}1.91$cm in panoramic view. Conclusion: Bone defects, which are determined by a healed section using a panoramic view, compared to CT scans which do not show up. Also we can estimate the critical size of defects for complete healing.

• Journal of Korean Neurosurgical Society
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• v.43 no.1
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• pp.5-10
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• 2008

Objective : To evaluate the surgical outcomes of ventral interbody grafting and anterior or posterior spinal instrumentation for the treatment of advanced spondylodiscitis with patients who had failed medical management. Methods : A total of 28 patients were evaluated for associated medical illness, detected pathogen, level of involved spine, and perioperative complications. Radiological evaluation including the rate of bony union, segmental Cobb angle, graft- and instrumentation-related complications, and clinical outcomes by mean Frankel scale and VAS score were performed. Results : There are 14 pyogenic spondylodiscitis, 6 postoperative spondylodiscitis, and 8 tuberculous spondylodiscitis. There were 21 males and 7 females. Mean age was 51 years, with a range from 18 to 77. Mean follow-up period was 10.9 months. Associated medical illnesses were 6 diabetes, 3 pulmonary tuberculosis, and 4 chronic liver diseases. Staphylococcus was the most common pathogen isolated (25%), and Mycobacterium tuberculosis was found in 18% of the patients. Operative approaches, either anterior or posterior spinal instrumentation, were done simultaneously or delayed after anterior aggressive debridement, neural decompression, and structural interbody bone grafting. All patients with neurological deficits improved after operation, except only one who died from aggravation as military tuberculosis. Mean Frankel scale was changed from $3.78{\pm}0.78$ preoperatively to $4.78{\pm}0.35$ at final follow up and mean VAS score was improved from $7.43{\pm}0.54$ to $2.07{\pm}1.12$. Solid bone fusion was obtained in all patients except only one patient who died. There was no need for prolongation of duration of antibiotics and no evidence of secondary infection owing to spinal instrumentations. Conclusion : According to these results, debridement and anterior column reconstruction with ventral interbody grafting and instrumentation is effective and safe in patients who had failed medical management and neurological deficits in advanced spondylodiscitis.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.4
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• pp.223-231
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• 2013

This paper presents a time-domain Gauss-Newton full-waveform inversion method for the material profile reconstruction in heterogeneous semi-infinite solid media. To implement the inverse problem in a finite computational domain, perfectly-matchedlayers( PMLs) are introduced as wave-absorbing boundaries within which the domain's wave velocity profile is to be reconstructed. The inverse problem is formulated in a partial-differential-equations(PDE)-constrained optimization framework, where a least-squares misfit between measured and calculated surface responses is minimized under the constraint of PML-endowed wave equations. A Gauss-Newton-Krylov optimization algorithm is utilized to iteratively update the unknown wave velocity profile with the aid of a specialized regularization scheme. Through a series of one-dimensional examples, the solution of the Gauss-Newton inversion was close enough to the target profile, and showed superior convergence behavior with reduced wall-clock time of implementation compared to a conventional inversion using Fletcher-Reeves optimization algorithm.

• Journal of Elementary Mathematics Education in Korea
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• v.17 no.2
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• pp.245-263
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• 2013

Mathematical learning via projects, which enables the reconstruction of curriculum through integration and emphasizes the process of solving problems by posing questions, has attracted the attention of the department of mathematics. This research is aimed at exploring the link between mathematics and project learning by analyzing an example of student-oriented project 'the secrets of pyramid' focused on understanding 'triangle' specifically designed for forth graders. From 115-hour process of subject-oriented project, this study reinterpreted the mathematical meaning of only 24 hours directly related to mathematics, especially to figure exploration. Consequently, this problem solving involved a variety of geometric activities as a process, such as measuring an angle, constructing a triangle, etc. Thus students attempt to actively participate in the process, thereby allowing them to learn how to measure things more accurately. Moreover, project learning improved students' understanding on not only plane figures but solid figures. This indicates that by project learning, learning from given problems or contents can be extended to other mathematical areas.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.4
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• pp.303-312
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• 2007

Recently several studies have been developed not only to apply bone materials to bony defect, but also to use osteogenic and osteoinductive materials to form bone more effectively. In 1998 Mark et al applied gel formation of PRP(platelet-rich plasma) in bony transplantation for mandibular reconstruction as one of the method of stimulating bone formation in maxillofacial area, which is contain of varies growth factors. After he reported that PRP accelerate bone formation, which is used in varies bone transplantation and augmentation with a good result. Especially there are amount of growth factors in PRP, and PRP increase angiogenesis, cell division, and mesenchymal cell growth. Moreover it is capable of osteoconduction, hemostatitis, anti-infection, forming the shape at transplantation, ease of handling, and recipient site stability. So it is known that success rate is high in bone transplantation. However PRP need tissue adhesive to make plasma to solid form. Thrombin and calcium chloride, component of PRP, is extracted from autogenic donor. So it is expensive to extract and there is possibility of hepatitis, AIDS, and hematogenous metastasis. After all, tissue adhesive have the limitation and danger of use. So we are willing to introduce that we had get some idea after using PRF(platelet-rich fibrin) in the various hard and soft tissue bony defect, which is self extracted simply and contain growth factors.

• ALGAE
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• v.23 no.4
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• pp.317-326
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• 2008

Marine algal flora and community structure were investigated seasonally at three sites in Ilkwang Bay on the southern east coast of Korea from May 2007 to February 2008. Total 103 species including 10 of green algae, 17 of brown algae, 76 of red algae were collected and identified. Among these species, 21 species were found throughout the year. Ulva pertusa, Enteromorpha linza, Grateloupia lanceolata, Chondracanthus intermedia and Caulacanthus ustulatus were distributed dominantly in upper intertidal zone. By contrast, crustose coralline algae, Grateloupia spp., Chondracanthus tenellus, Prionitis cornea and Sargassum spp. occurred predominantly in middle intertidal zone. Grateloupia spp., Sargassum spp., Ecklonia cava and Ulva pertusa were dominant in lower intertidal zone. Annual mean biomass in wet weight was 478.3 g m$^{-2}$. Maximum biomass was recorded in site 1 (731.8 g m$^{-2}$), and minimum was recorded in site 3 (78.5 g m$^{-2}$). The R/P, C/P and (R + C)/P value reflecting flora characteristics were 4.47, 0.59 and 5.06, respectively. Two groups produced by cluster analysis, one including sites 1, 2 and the other including site 3, showed meaningful difference in similarity, each other. Site 3 showed the limited species composition due to inflow of fresh water and absence of solid substratum. However, there was no significant difference between site 1 and site 2. In conclusion, the number of marine algae species and biomass in Ilkwang Bay were markedly reduced comparing with the previous studies. These suggest that a solution for reconstruction of the poor marine algal vegetation is considerably demanded.

• Archives of Reconstructive Microsurgery
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• v.7 no.1
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• pp.54-61
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• 1998

Free vascularized fibular is the most usuful bony donor of the long bone reconstruction in reconstructive microsurgical field. It has many benifits such as very strong strut tubular bone, very reliable vascular anatomy with large vascular diameter with long pedicle, minimal donor site morbity too. In that situations of the huge long bone defects in distal femur or proximal tibia, the defective bony shape and strength of the transplanted fibular bone is not enough if only one strut of the fibula is transfered. The bony circulation of the fibula has two ways, one from nutrient artery via peroneal artery through nutrient foramen which makes endosteal arterial network inside of the fibula, another way is periosteal network through outside encircling vascular network of the bone which distributed in muscle sleeves of the fibular diaphysis. Authors modified free vascularized fibular bone graft with transverse osteotomy is made from the anterolateral aspect of the fibular shaft just distal to entry of the nutrient artery. This produces two vascularized bone struts that may be folded pararell to each other but that remain connected by the periosteum and muscle cuff surrounding the peroneal artery and veins. The proximal strut is vascularized by both a periosteal and endosteal blood supply, whereas the distal strut is vascularized by a periosteal blood supply alone. This procedure can call "doule barrel" free vascularized fibular graft. We performed 7 cases of doule barrel fashined fibular transplantation on distal femur and proximal tibial large defects. Average bone union time takes 7 months from that procedure. There were no significant bone union time differences between both proximal and distal struts. After solid union of the transfered double barrel fibular graft, there were no stress fracture in our series. We can propose double barrel free vascualized fibular graft is usuful method in that cases with very large bone defect on large long bones especially metaphyseal defects.

• Applied Microscopy
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• v.51
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• pp.4.1-4.12
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• 2021

Fluorescence in situ hybridization (FISH) is a technique to visualize specific DNA/RNA sequences within the cell nuclei and provide the presence, location and structural integrity of genes on chromosomes. A confocal Whole Slide Imaging (WSI) scanner technology has superior depth resolution compared to wide-field fluorescence imaging. Confocal WSI has the ability to perform serial optical sections with specimen imaging, which is critical for 3D tissue reconstruction for volumetric spatial analysis. The standard clinical manual scoring for FISH is labor-intensive, time-consuming and subjective. Application of multi-gene FISH analysis alongside 3D imaging, significantly increase the level of complexity required for an accurate 3D analysis. Therefore, the purpose of this study is to establish automated 3D FISH scoring for z-stack images from confocal WSI scanner. The algorithm and the application we developed, SHIMARIS PAFQ, successfully employs 3D calculations for clear individual cell nuclei segmentation, gene signals detection and distribution of break-apart probes signal patterns, including standard break-apart, and variant patterns due to truncation, and deletion, etc. The analysis was accurate and precise when compared with ground truth clinical manual counting and scoring reported in ten lymphoma and solid tumors cases. The algorithm and the application we developed, SHIMARIS PAFQ, is objective and more efficient than the conventional procedure. It enables the automated counting of more nuclei, precisely detecting additional abnormal signal variations in nuclei patterns and analyzes gigabyte multi-layer stacking imaging data of tissue samples from patients. Currently, we are developing a deep learning algorithm for automated tumor area detection to be integrated with SHIMARIS PAFQ.