• Structural Engineering and Mechanics
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• v.59 no.6
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• pp.993-1017
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• 2016

Helicopters are essential for supporting offshore oil and gas activities around the world. To ensure accessibility for helicopters, helideck structures must satisfy the safety requirements associated with various environmental and accidental loads. Recently, offshore helideck structures have used aluminium because of its light weight, low maintenance requirements, cost effectiveness and easy installation. However, section designs of aluminum pancakes tend to modify and/or change from the steel pancakes. Therefore, it is necessary to optimize section design and evaluate the safety requirements for aluminium helideck. In this study, a design procedure was developed based on section optimization techniques with experimental studies, industrial regulations and nonlinear finite element analyses. To validate and verify the procedure, a new aluminium section was developed and compared strength capacity with the existing helideck section profiles.

• Safety and Health at Work
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• v.10 no.2
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• pp.248-249
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• 2019

• Proceedings of the Materials Research Society of Korea Conference
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• 2004.05a
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• pp.24-24
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• 2004

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5257-5261
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• 2012

Background: High incidence of breast cancer and its fatal effect has reached an alarming stage across the globe, including the third world countries. Many factors have been reported to be associated with the development of breast cancer but detailed structural and functional information is missing. CA 15-3 is one of the known potential tumor marker of breast cancer; however little is known about structure and functional site of this protein. Present study aims to investigate the functional role of CA 15-3 in breast cancer, especially in development and metastasis. Material and Methods: Hundred female breast cancer patients confirmed by histopathological reports were included in the study. Their physiological characters were recorded in a performa. Enzyme linked immunosorbent assay (ELISA) technique was used to estimate serum CA 15-3 level. Immunohistochemistry was done for estrogen (ER), progesterone (PR) and Her2/neu receptors expression. Results: The study revealed the details of physiological characteristics of female breast cancer. Mean age was $37.72{\pm}5.99$ and $55.05{\pm}7.28$ years and serum CA 15-3 (MUC1) level was $60.47{\pm}8.59$ and $63.17{\pm}4.58$ U/ml in pre and post-menopause respectively, and both groups of women had sedentary life style. Their receptor status especially of progesterone, estrogen and HER-2/neu were positive in 50% of premenopausal women and 65% of postmenopausal women. Conclusion: There are multiple physiological factors promoting breast cancer. High serum CA 15-3 level and hormonal imbalance of ER, PR and Her2/neu appears to be the main cause of breast cancer. It may be possible that the functional sites of these proteins may be altered which may increase the chances of metastasis in breast cancer.

• International Journal of Concrete Structures and Materials
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• v.9 no.3
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• pp.381-390
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• 2015

Investigating the microstructure of hardened cement mixtures with the aid of advanced technology will help the concrete industry to develop appropriate binders for durable building materials. In this paper, morphological, mineralogical and thermogravimetric analyses of autoclave-cured mixtures incorporating ground dune sand and ground granulated blast furnace slag as partial cementing materials were investigated. The microstructure analyses of hydrated products were conducted using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), differential thermal analysis (DTA), thermo-graphic analysis (TGA) and X-ray diffraction (XRD). The SEM and EDX results demonstrated the formation of thin plate-like calcium silicate hydrate plates and a compacted microstructure. The DTA and TGA analyses revealed that the calcium hydroxide generated from the hydration binder materials was consumed during the secondary pozzolanic reaction. Residual crystalline silica was observed from the XRD analysis of all of the blended mixtures, indicating the presence of excess silica. A good correlation was observed between the compressive strength of the blended mixtures and the CaO/$SiO_2$ ratio of the binder materials.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.205-216
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• 2015

Background: Many developing countries are lagging behind in reporting epidemiological data for individual central nervous system (CNS) tumors. This paper aimed to elicit patterns for the epidemiology of individual World Health Organization (WHO) classified CNS tumors in countries registered by WHO as "developing". Materials and Methods: Cyber search was carried out through 66 cancer networks/registries and 181 PubMed published papers that reported counts of CNS tumors for the period of 2009-2012. The relationship between the natural log of incidence Age Standardized Rate (ASR) reported by Globocan and Latitude/ Longitude was investigated. Results: Registries for 21 countries displayed information related to CNS tumors. In contrast tends for classified CNS tumor cases were identified for 38 countries via 181 PubMed publications. Extracted data showed a majority of unclassified reported cases [PubMed (38 countries, 45.7%), registries (21 countries, 96.1%)]. For classified tumors, astrocytic tumors were the most frequently reported type [PubMed (38 countries, 1,245 cases, 15.7%), registries (21 countries, 627 cases, 1.99%]. A significant linear regression relationship emerged between latitudes and reported cases of CNS tumors. Conclusions: Previously unreported trends of frequencies for individually classified CNS tumors were elucidated and a possible link of CNS tumors occurrence with geographical location emerged.

• Composite Materials and Engineering
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• v.3 no.3
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• pp.167-178
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• 2021

In the present paper, the destructive behavior of distilled water, salty water, sulfuric acid, and heat on glass/vinyl ester composites was investigated by experimental methods. Hetron 922 vinyl ester resin and two types of mat and woven glass fibers as the reinforcements were used to fabricate composite test samples. All samples were immersed in distilled water, salty water, and sulfuric acid with three different concentrations. The tests were performed at 20℃ and 70℃ for the exposure duration of 1, 2, 4, and 8 weeks. Bending tests were performed after aging for all composite samples to check the degradation of the bending modulus and strength. The results show that the effect of distilled water, in comparison with salty water, on the degradation of composite samples was significant. On the other hand, almost non-sensitivity of concentrations of salty water on the weight gain of specimens has been observed. In addition, it was also observed that the degradation of samples at 70℃ temperature is much more than that of at 20℃. Also, it was observed that the flexural modulus of virgin specimens exposed to salty water (2% concentration) has been recovered just after two weeks of immersion. Furthermore, in some cases, composite samples under the sulfuric acid solution have lost almost 80% of their mechanical properties.

• Proceedings of the Membrane Society of Korea Conference
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• 1991.04a
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• pp.5-8
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• 1991

Membrane techology is reapidly replacing and/or augmenting the traditional separation processes in many industries. In some cases, it opens new markets. Research and development in academia and industry have proven that the new technology is cost effective and viable. The future of membrane technology looks bright.

• The Research Journal of the Costume Culture
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• v.22 no.5
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• pp.655-669
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• 2014

This study was to examine the service and the product evaluation factors of Korean internet fashion shopping malls and to suggest marketing implications for Korean internet fashion shopping malls wanting to expand into the Chinese market. This study conducted a questionnaire survey for college female students in Qingdao, China, who have shopped at Korean internet shopping malls, and 310 surveys were used in the final analysis, frequency analysis, factorial analysis, and regression analysis. The results of the study were as follows. First, Most of the respondents answered that they found the Korean internet fashion shopping malls through the internet, and the most purchased item was outer clothing. Second, the system stability and web site structure excellence factors had a positive influence on the service satisfaction for the shopping mall 'S', while the system satisfaction, service efficiency, interactivity and web site structure excellence factors had positive influences on service satisfaction for the shopping mall 'P', and the system satisfaction, service efficiency, interactivity factors had positive influences on service satisfaction for the shopping mall 'N'. Third, examining the correlation between product satisfaction for the shopping mall 'S', 'P', and 'N' with fashion product evaluation factors showed that, design factors and quality excellence factors of the three shopping malls had positive influences on product satisfaction. The results of this research provide useful information in forming an efficient operating system and improving marketing strategies for internet fashion shopping malls planning to enter or having already entered the Chinese market.

• Macromolecular Research
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• v.17 no.6
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• pp.378-387
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• 2009

This research compared three methods for producing and processing nanocomposite polypropylene filament yarns with permanent antimicrobial efficiency. The three methods used to mix antimicrobial agents based on silver nano particles with PP were as follows: 1) mixing of PP powder and inorganic nanocomposite filler with the appropriate concentration using a twin-screw extruder and preparing granules, 2) method 1 with a singlerather than twin-screw extruder, and 3) producing the masterbatch by a twin-screw extruder and blending it with PP in the melt spinning process. All pure polypropylene samples and other combined samples had an acceptable spinnability at the spinning temperature of $240^{\circ}C$ and take-up speed of 2,000 m/min. After producing as-spun filament yarns by a pilot plant, melt spinning machine, the samples were drawn, textured and finally weft knitted. The physical and structural properties (e.g., linear density, tenacity, breaking elongation, initial modulus, rupture work, shrinkage and crystallinity) of the as-spun and drawn yarns with constant and variable draw ratios (the variable draw ratio was used to gain a constant breaking elongation of 50%) were investigated and compared, while DSC, SEM and FTIR techniques were used to characterize the samples. Finally, the antibacterial efficiency of the knitted samples was evaluated. The experimental results revealed that the crystallinity reduction of the as-spun yarn obtained from method 1 (5%) was more than that of method 2 (3%), while the crystallinity of the modified as-spun yarns obtained with method 3 remained unchanged compared to pure yarn. However, the drawing procedure compensated for this difference. By applying methods 2 and 3, the drawing generally improved the tenacity and modulus of the modified fibers, whereas method 1 degraded the constant draw ratio. Although the biostatic efficiency of the nanocomposite yarns was excellent with all three methods, the modified fabrics obtained from methods 1 and 2 showed a higher bioactivity.