• Journal of Gastric Cancer
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• v.12 no.2
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• pp.63-72
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• 2012

Since the first laparoscopic gastrectomy for cancer was reported in 1994, minimally invasive surgery is enjoying its wide acceptance. Numerous procedures of this approach have developed, and many patients have benefited from its effectiveness, which has been recently demonstrated for early gastric cancer. However, since laparoscopic surgery is not exempt from some limitations, the robotic surgery system was introduced as a solution by the late 1990's. Many experienced surgeons have embraced this new emerging method that provides undoubted technical and minimally invasive advantages. To date, several studies have concentrated to this new system, and have compared it with open and laparoscopic approach. Most of them have reported satisfactory results concerning the post-operative short-term outcomes, but almost all believe that the role of robotic gastrectomy is still out of focus, especially because long-term outcomes that can prove robotic oncologic equivalency are lacking, and operative costs and time are higher in comparison to the open and laparoscopic ones. This article is a review about the current status of robotic surgery for the treatment of gastric cancer, especially, focusing on the technical aspects, comparisons to other approaches and future prospects.

• Computers and Concrete
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• v.2 no.5
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• pp.345-366
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• 2005

This work presents an assessment of the computational performance of a vector-parallel implementation of probabilistic model for concrete cracking in 3D. This paper shows the continuing efforts towards code optimization as reported in earlier works Paz, et al. (2002a,b and 2003). The probabilistic crack approach is based on the direct Monte Carlo method. Cracking is accounted by means of 3D interface elements. This approach considers that all nonlinearities are restricted to interface elements modeling cracks. The heterogeneity governs the overall cracking behavior and related size effects on concrete fracture. Computational kernels in the implementation are the inexact Newton iterative driver to solve the non-linear problem and a preconditioned conjugate gradient (PCG) driver to solve linearized equations, using an element by element (EBE) strategy to compute matrix-vector products. In particular the paper analyzes code behavior using OpenMP directives in parallel vector processors (PVP), such as the CRAY SV1 and CRAY T94. The impact of the memory architecture on code performance, and also some strategies devised to circumvent this issue are addressed by numerical experiment.

• Journal of the Korean institute of surface engineering
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• v.55 no.4
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• pp.231-235
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• 2022

As environmental pollution becomes more serious, the demand for electric vehicles (EVs) and lithium-ion batteries for electric vehicles is rapidly increasing worldwide. Accordingly, the amount of waste batteries is also increasing, and a technology for recycling and reusing them is required. In order to reuse a used battery, it is necessary to non-destructively diagnose the deterioration condition of the battery. Therefore, in this study, we investigate the diagnosis of degradation for parallel-connected lithium-ion battery cells through non-constructive electrochemical approach. As the number of parallel-connected cells increased, in addition to linear degradation, abrupt step-like degradation occurred, which is attributed to the predominant degradation of specific cells. In addition, it is confirmed that deteriorated cells among multiple cells can be distinguished through a simple measurement of open circuit voltage (OCV).

• Nuclear Engineering and Technology
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• v.56 no.2
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• pp.611-623
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• 2024

The ISP-47 TOSQAN experiment was analyzed with containmentFOAM which is an open-source CFD code based on OpenFOAM. The containment phenomena taking place during the experiment are gas mixing, stratification and wall condensation in a mixture composed of steam and non-condensable gas. The k-ω SST turbulence model was adopted with buoyancy turbulence models. The wall condensation model used is based on the diffusion layer approach. We have simulated the full TOSQAN experiment which had a duration 20000 s. Sensitivity studies were conducted for the buoyancy turbulence models with SGDH and GGDH and there were not significant differences. All the main features of the experiments namely pressure history, temperature, velocity and gas species evolution were well predicted by containemntFOAM. The simulation results confirmed the formation of two large flow stream circulations and a mixing zone resulting by the combined effects of the condensation flow and natural convection flow. It was found that the natural convection in lower region of the vessel devotes to maintain two large circulations and to be varied the height of the mixing zone as result of sensitivity analysis of non-condensing wall temperature. The computational results obtained with the 2D mesh grid approach were comparable to the experimental results.

• Journal of Korean Foot and Ankle Society
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• v.9 no.2
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• pp.193-196
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• 2005

A posterior 3-portal arthroscopic approach with the patient in the prone position provides a novel and optimal approach for isolated subtalar arthrodesis. This approach facilitates access to the posterior talocalcaneal facet and facilitates safe access with regard to the posteromedial neuromuscular bundle. The technique involves prone positioning, establishment of two posterolateral portals and one posteromedial portal, arthroscopic posterior talocalcaneal facet debridement, percutaneous morcellized bone grafting and internal screw fixation. Preliminary results have shown high patient satisfaction, an excellent fusion rate and less postoperative morbidity than open subtalar arthrodesis.

• International Journal of Quality Innovation
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• v.6 no.1
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• pp.43-57
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• 2005

Action learning motivates students to solve open-ended problems by 'developing skills through doing'. This paper reviews the concept of action learning and discusses the adoption of action learning approach to teach operations management at universities. It presents the design and delivery of an action-learning course at City University of Hong Kong. The course incorporates classroom lectures, tutorials and an action-learning workshop. The experience gained proves that action learning facilitates student participation and teamwork and provides a venue of accelerating learning where enables students to handle dynamic problem situations more effectively. The paper concludes that adopting action-learning approach can help lecturers to enhance quality teaching in operations management courses, and provide an alternate means of effective paradigm other than traditional classroom teaching and/or computer-based training at universities.

• Communications for Statistical Applications and Methods
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• v.22 no.1
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• pp.55-67
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• 2015

An important problem in cluster analysis is the selection of variables that define cluster structure that also eliminate noisy variables that mask cluster structure; in addition, outlier detection is a fundamental task for cluster analysis. Here we provide an automated K-means clustering process combined with variable selection and outlier identification. The Automated K-means clustering procedure consists of three processes: (i) automatically calculating the cluster number and initial cluster center whenever a new variable is added, (ii) identifying outliers for each cluster depending on used variables, (iii) selecting variables defining cluster structure in a forward manner. To select variables, we applied VS-KM (variable-selection heuristic for K-means clustering) procedure (Brusco and Cradit, 2001). To identify outliers, we used a hybrid approach combining a clustering based approach and distance based approach. Simulation results indicate that the proposed automated K-means clustering procedure is effective to select variables and identify outliers. The implemented R program can be obtained at http://www.knou.ac.kr/~sskim/SVOKmeans.r.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.5
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• pp.349-356
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• 2012

Osteochondroma is one of the most common benign tumors that occur in the bone, but in the head and neck region, osteochondroma appears rarely. Malocclusion, temporomandiublar disorders and facial asymmetry can occur in most cases with osteochondroma of the mandibular condyle. Most surgeons prefer massive removal of osteochondroma and reconstruction of condyle, simultaneously, to prevent various complications, such as a lateral open bite on the contralateral side. We report a surgical treatment and reconstruction of osteochondroma on a mandibular condyle through intraoral approach.

• Journal of Korean Society for Quality Management
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• v.30 no.2
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• pp.60-71
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• 2002

The business's paradigm is rapidly changing from product-out to market-in due to Open-door, intensive competitiveness, the variety of the customer's need. Starting from this needs of the times, CRM based on the understanding which company's value coming from the customers is in everyone's mouth. But it can said that it stay in the Immature level at the understanding of this Importance, strategic approach Therefore, the basic objective of this study is to grope the strategic approach that can stand out basic competitive power of department store during the construction of CRM in department store. To achieve the objective of this study, first, we will find out the general error which companies commit during the construction of CRM, second, we will consider the grafting possibility with e-CRM in the case of the CRM's construction in department store. Finally, we will exhibit the conceptual model of department store's CRM which apply the membership card for effectiveness of the Customer Relationship Management.

• Journal of Energy Engineering
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• v.24 no.2
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• pp.55-58
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• 2015

The mesoporous metal organic framework structure Fe-BTC was successfully synthesized by hydrothermal process with noticeable yield. The synthesis operation was conducted at intermediate temperature and for shortened operation time as compared to conventional procedures. This process approach with reduced operating temperature and shortened operation time may open an opportunity window towards process economy with reduction in energy consumption. A simple mathematical approach of diffraction indexing using X-ray diffraction patterns of synthesized powder was employed to confirm its crystalline nature and to investigate its high temperature stability. The crystallite size was calculated by using Debye-Scherrer equation.