• Journal of the Society of Naval Architects of Korea
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• v.39 no.1
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• pp.28-37
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• 2002

In this study nonlinear dynamic behaviors of towed tow-tension cables are numerically analysed. In the case of a taut cable analysis, a bending stiffness term is usually neglected due to its minor effect but it plays an important role in a low-tension cable analysis. A low-tension cable may experience large displacements due to relatively small restoring forces and thus the effects of fluid and geometric non-linearities become predominant. The bending stiffness and non-linearity effects are considered in this work. In order to obtain dynamic behaviors of a towed low-tension cable, three-dimensional nonlinear dynamic equation is described and discretized by employing a finite difference method. An implicit method and Newton-Raphson iteration are adopted for the time integration and nonlinear solutions. For the calculation of huge size of matrices. block tri-diagonal matrix method is applied, which is much faster than the well-known Gauss-Jordan method in two point boundary value problems. Some case studies are carried out and the results of numerical simulations are compared with those of a in-house program of WHOI Cable with good agreements.

• Journal of the Korean Wood Science and Technology
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• v.41 no.3
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• pp.173-180
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• 2013

This study was carried to provide basic data for the research of the effect of PEG impregnation on preventing wood from cracking during heat treatment. Three popular softwood species were selected for investigating the PEG penetration rate and retention depending on PEG molecular weight, PEG retention after heat treatment and their EMCs. The average retentions of PEG400 were reversely proportional to the basic densities of three species and those of the other PEGs showed similar behaviour as well. It is obvious that PEG retention decreased as PEG molecular weight increased with a species. PEG impregnation increased or decreased the moisture contents of the specimens within 2%, and increased their basic densities by 16.8% as a maximum. The Weight Percentage Losses of PEG400 during heat treatment were the largest among three PEG levels, which implied that lower molecular weight PEG leached more than the highers. There was less difference in EMC between PEG impregnated and control specimens at low RH, but their difference increased at high RH.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.121-126
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• 2013

Background: Significance of HPV infection and genic mutation of APC and K-ras in rectal cancer has been investigated but not clarified. The objective of our study was to investigate these parameters in patients with rectal cancer to analyze correlations with biological behaviour, to determine relationships among the three, and also to demonstrate survival prognosis effects. Methods: From December 2007 to September 2008, 75 rectal cancer cases confirmed by histopathology in the Tumor Hospital of Xinjiang Medical University were enrolled. The control group consisted of normal rectal mucous membrane taken simultaneously, a least 10 cm distant from the carcinoma fringe. HPV DNA, the MCR of APC and exon-1 of K-ras were detected by PCR and PCR-SSCP. All results were analyzed in relation to clinical pathological material, using chi-square and correlation analysis via SPSS.13 and Fisher's Exact Probability via STATA. 9.0. All 75 patients were followed up for survival analysis using Kaplan-Meier and Log-rank tests. Results: 55 out of 75 cases demonstrated gene HPV L1 while it was notdetected in normal rectal mucosa tissue. HPV infection was correlated with age and lymphatic metastasis (P<0.05) but not other characteristics, such as ethnicity, tumor size, histological type, tumor type, Duke's stage and infiltration depth. Some 43 cases exhibited APC genic mutation (57.3%) and 34 K-ras genic mutation (45.3%). APC genic mutation was correlated with gender(P<0.05), but not age, histological type, infiltration depth, lymphatic metastasis and Duke's stage. In 55 cases of rectal cancer with HPV infection, there were 31 cases with genic mutation of APC (56.4%) and 24 with genic mutation of K-ras (43.6%). For the 20 cases of rectal cancer with non-HPV infection, the figures were 12 cases (60%) and 10 (50.0%), respectively, with no significant relation. Survival analysis showed no statistical significance for K-ras genic mutation, APC genic mutation or HPV infection (P>0.05). However, the survival time of the patients with HPV infection was a little shorter than in cases without HPV infection. Conclusions: Our results suggest that HPV infection might be an important factor to bring about malignant phenotype of rectal cancer and influence prognosis. Genic mutation of APC and K-ras might be common early molecular events of rectal cancer, but without prognostic effects on medium-term or early stage patients with rectal cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3897-3901
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• 2016

Background: Breast cancer is by far the most frequent cancer of women (23% of all cancers), ranking second overall when both sexes are considered together. Since there has been change in clinico-pathological factors and treatment profiles for breast cancer patients over the years, the present study to evaluate the change trends in India. Materials and Methods: A detailed analysis was carried out with respect to age, menopausal status, family history, disease stage, surgery performed, histopathology, hormone receptor status, and use of chemotherapy or hormonal therapy. Change in various clinico-pathological factors and treatments of breast cancer cases was recorded and analysed. Results: Mean age at presentation was found to be earlier in 2005-2006 compared with 1997-98 (p value: 0.046). More premenopausal women were diagnosed with breast cancer in 2005-2006 when this was compared with initial years of assessment (p value ${\leq}0.001$). When change in the receptor status was evaluated, we observed that there was a decrease in cases of ER and PR receptor positivity which was significant (p value: 0.007). Over the period of time, more f patients were not offered surgery initially in view of advanced disease when the two time periods were compared (p value: ${\leq}0.001$). There was a significant increase in patients who were initially offered neo-adjuvant chemotherapy in view of advanced disease at presentation (p value: ${\leq}0.001$). There was increasing number of patients who received palliative treatment for symptoms in 2005-2006 when compared to patients treated in 1997-98((p value: ${\leq}0.001$). Conclusions: Changes in mean age at presentation, premenopausal status, and stage at presentation have occurred over the years. More aggressive patterns of disease have become more common with early age at presentation and aggressive biological behaviour with receptor negative tumours.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.4175-4179
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• 2016

Background: Oral cavity cancer (OCC) is one of the most common cancers worldwide. No studies have reported on the prevalence and epidemiologic risk factors of oral premalignant lesions (OPLs) in Thailand. The purpose of this study was to investigate the prevalence of OPLs and associated factors in Roi Et Province, Thailand. Materials and Methods: To investigate the prevalence of OPLs, a cross-sectional descriptive study was conducted in which 2,300 subjects over 40 years of age were recruited and screened for the prevalence of OPLs. To identify factors associated with OPLs, a matched case-control study was used in which the subjects were 102 cases with OPL and 102 matched controls without OPLs. The studies were conducted in Roi Et Province during the period 1 February, 2014, to 30 April, 2014, and the data were collected by the use of a structured interview questionnaire and by extraction of information from medical records. Data analyses involved the use of descriptive statistics, McNemar's test, and conditional logistic regression. Results: The overall prevalence of OPLs was 3.8%, and no-one was diagnosed with more than one type of OPL. The factors found to be associated with a statistically significant higher risk of an OPL were betel nut chewing, smoking, and alcohol consumption. The associations with these factors were strong, especially for betel nut chewing and smoking. Conclusions: The habits of betel nut chewing, smoking, and alcohol use are confirmed as factors associated with OPLs in a population of Roi Et Province, Thailand. Campaigns to reduce such risk healthy behaviour are needed, but whether any actual decrease will prevent the eventual transformation of an OPL into an OCC remains an open question.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.3
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• pp.80-91
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• 2008

The Purpose of this study is the applicaion of social network analysis for expanding the use of spatial data in local government. Spatial data generated from UIS projects play very important roles as a means of supporting decision making and solving complicated urban problems, but the utilization of the spatial data has not reach the expected level, considering to the huge amount of investment. Accordingly, there should be efforts in efficient management of spatial data, establishment of a sharing system, and expanded utilization of spatial data. Social network analysis applied to this research is a theory that explains the behaviors and patterns of units forming the system and measures distances between nodes, strength, etc. based on relations among nodes forming the network and the structural characteristics of the network. According to the results of surveying civil servants who were using spatial data on Busan Metropolitan City, obstacles to the sharing of spatial data were mostly non technical factors related to data users' attitude and their relations with circumstances. In order to expand the use of spatial data, this study performed social network analysis that applied the theory of planned behavior and examined the flow of spatial data, and by doing so, we analyzed related personnel's perception, identified obstacles to data sharing, and suggested a framework for promoting the expanded utilization of spatial data.

• Steel and Composite Structures
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• v.6 no.6
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• pp.459-477
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• 2006

A theoretical research project is undertaken to develop integrated analysis and design tools for long span composite beams in modern high-rise buildings, and it aims to develop non-linear finite element models for practical design of composite beams. As the first paper in the series, this paper presents the development study as well as the calibration exercise of the proposed finite element models for simply supported composite beams. Other practical issues such as continuous composite beams, the provision of web openings for passage of building services, the partial continuity offered by the connections to columns as well as the behaviour of both unprotected and protected composite beams under fires will be reported separately. In this paper, details of the finite elements and the material models for both steel and reinforced concrete are first described, and finite element studies of composite beams with full details of test data are then presented. It should be noted that in the proposed finite element models, both steel beams and concrete slabs are modelled with two dimensional plane stress elements whose widths are assigned to be equal to the widths of concrete flanges, and the flange widths and the web thicknesses of steel beams as appropriate. Moreover, each shear connector is modelled with one horizontal spring and one vertical spring to simulate its longitudinal shear and pull-out actions based on measured load-slippage curves of push-out tests of shear connectors. The numerical results are then carefully analyzed and compared with the corresponding test results in terms of load mid-span deflection curves as well as load end-slippage curves. Other deformation characteristics of the composite beams such as stress and strain distributions across the composite cross-sections as well as distributions of shear forces and slippages in shear connectors along the beam spans are also examined in details. It is shown that the numerical results of the composite beams compare well with the test data in terms of various load-deformation characteristics along the entire deformation ranges. Hence, the proposed analysis and design tools are considered to be simple and yet effective for composite beams with practical geometrical dimensions and arrangements. Structural engineers are strongly encouraged to employ the models in their practical work to exploit the full advantages offered by composite construction.

• Geophysics and Geophysical Exploration
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• v.9 no.1
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• pp.1-9
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• 2006

Geological storage of captured $CO_2$ is a new way of reducing greenhouse gas emissions to protect the climate, but is based on the established technology associated with injection of fluids underground. The geological formations of interest for this technique include operational and depleted oil and gas fields, and deep saline aquifers. Prediction of storage performance will depend on models of the behaviour of $CO_2$ in geological formations; these need to be refined and verified, and methods of monitoring developed and proved. These needs can be met through monitored demonstration and research projects. Current commercial projects that are demonstrating $CO_2$ storage include Sleipner, Weyburn, ORC, and In Salah; research projects include West Pearl Queen, Nagaoka, and Frio. In this paper, some of the monitored injection projects are described. The reservoirs employed for storing $CO_2$, and the associated monitoring techniques, are briefly reviewed. It is argued that small-scale research projects, used to develop techniques and prove models, are complementary to the large-scale monitored injections that will establish the viability of this technique for mitigating climate change.

• Geophysics and Geophysical Exploration
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• v.9 no.1
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• pp.10-18
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• 2006

We measured the changes in P-wave velocity that occur when injecting $CO_2$ in gaseous, liquid, and supercritical phases into water-saturated anisotropic sandstones. P-wave velocities were measured in two cylindrical samples of Tako Sandstone, drilled along directions normal and parallel to the bedding plane, using a piezo-electric transducer array system. The velocity changes caused by $CO_2$ injection are typically -6% on average, with maximum values about -16% for the case of supercritical $CO_2$ injection. P-wave velocity tomograms obtained by the differential arrival-time method clearly show that $CO_2$ migration behaviour is more complex when $CO_2$ flows normal to the bedding plane than when it flows parallel to bedding. We also found that the differences in P-wave velocity images were associated both with the $CO_2$ phases and with heterogeneity of pore distribution in the rocks. Seismic images showed that the highest velocity reduction occurred for supercritical $CO_2$ injection, compared with gaseous or liquid $CO_$ injection. This result may justify the use of the seismic method for $CO_2$ monitoring in geological sequestration.

• Journal of the Korean Geotechnical Society
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• v.16 no.4
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• pp.141-148
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• 2000

For the construction of 4.8km long Multi-Purpose Jamuna Bridge in Bangladesh, 2 or 3 large diameter open-ended steel pipe piles were used for the foundation of piers. A total of 123 piles were driven for 50 piers and 2 test piles from the river bed through the normally-consolidated upper sand layer and rested n top of gravel layer. Two types of piles, having 3.15 or 2.50m diameter and variable wall thickness in the range of 40 to 60mm, were driven to the depths of 69 to 74m with the rake of 6:1 by connecting 2 or 3 pieces of short piles. Dynamic pile tests were performed on 24 selected piles during pile driving and soil plug length inside the pile was also measured after driving of each short section.These piles were plugged with soil to, though slightly affected by pile diameters, about 75% of total length of pile driven. Active plug at the tip of pile contributed substantial amount of inner skin friction to the total capacity. Piles soon after driving showed a skin-friction dominant pile behaviour, tat is, 90% of total capacity being developed by skin resistance. Quakes values and Smith damping factors were almost constant regardless of pile diameters. This result reflects the influence of uniform soil condition at the site.