• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.6
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• pp.29-33
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• 2004

A major concern at present is the simultaneous control of transverse thickness profile and flatness in the finishing stages of hot rolling process. The mathematical modeling of hot rolling process has long been recognized to be a desirable approach to investigate rolling operating practice and the design of mill equipment to improve productivity and quality. However, many factors make the mathematical analysis of the rolling process very complex and time-consuming. In order to overcome these problems and to obtain an accurate rolling force, the predicted model of rolling force using neural networks has widely been employed. In this paper, Radial Basis Function Network(RBFN) is applied to improve the accuracy of rolling force prediction in hot rolling mill. In order to verify and analyze the performance of applied neural network the comparison with the measured rolling force and the predicted results using two different neural networks-RBFN, MLP, has respectively been carried out. The results obtained using RBFN neural network are much more accurate those obtained the MLP.

• Structural Engineering and Mechanics
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• v.36 no.3
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• pp.247-278
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• 2010

The study of the seismic vulnerability of masonry buildings requires structural properties of walls such as stiffness, ultimate load capacity, etc. In this article, a method is suggested for modeling the masonry walls under in-plane loading. At the outset, a set of analytical equations was established for determining the elastic properties of an equivalent homogeneous material of masonry. The results for homogenized unreinforced brick walls through detailed modeling were compared in different manners such as solid and perforated walls, in-plane and out-of-plane loading, etc, and it was found that this method provides suitable accuracy in estimation of the wall linear properties. Furthermore, comparison of the results of proposed modeling with experimental out coming indicated that this model considers the non linear properties of the wall such as failure pattern, performance curve and ultimate strength, and would be appropriate to establish a parametric study on those prone factors. The proposed model is complicated; therefore, efforts need to be made in order to overcome the convergency problems which will be included in this study. The nonlinear model is basically semi-macro but through a series of actions, it can be simplified to a macro model.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4307-4312
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• 2013

Breast cancer is the most frequent malignancy of women worldwide. It is the leading cause of female cancer related disability and mortality. In Saudi Arabia breast cancer ranks first among cancerous diseases in females. In the Gulf region, and especially in Saudi Arabia, few studies have been conducted to address breast cancer awareness. The purpose of the current study was therefore to investigate the level of breast cancer awareness among Saudi females in Jeddah, focusing on knowledge of breast cancer warning signs, risk factors, screening programs and breast self-examination (BSE). The design of this study was an exploratory correlational analysis. The sample comprised 200 Saudi females aged 20 and older living in Jeddah. Data were collected using face-to-face interviews. Breast cancer awareness was measured using a modified Arabic version of the Breast Cancer Awareness Measure (Breast CAM) version 2. Descriptive statistical analysis, Pearson's Product Moment correlation coefficients and ANOVA test were used to answer study questions. Out of 200 participants, 50.5% were aware of breast lump as a warning sign of breast cancer, 57.5% claimed that family history was risk factor, 20.5% had undergone breast screening, 79% heard about BSE, and 47.5% knew how to perform BSE. Findings indicated that Saudi females level of awareness of breast cancer is very inadequate. Public awareness interventions are needed in order to overcome an ever-increasing burden of this disease among Saudi females.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.517-522
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• 2003

Exact estimation of evapotranspiration is important to understand natural phenomena and social issues associated with the climate such as irrigation scheme, reservoir water management, and many other meteorological and climatological problems. To overcome limits of point measurement of evapotranspiration, several models have been developed through the techniques of remote sensing and Geographical Information System. SEBAL model is one of them, based on the energy balance equation, and it has a lot of advantages such as that it requires relatively small empirical relations. In this study, the SEBAL model has been calibrated and validated in Geumgang upper basin, Bochung-stream basin, Korea with 5 satellite images Landsat 5 TM. In validation, the results of SEBAL model were compared with those by Merton method. After validation, the spatial and temporal characteristics of the distribution of evapotranspiration within the basin were analyzed with 3 factors, the aspect of slope, the angle of slope, and the land cover.

• 전자공학회논문지 IE
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• v.46 no.4
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• pp.66-72
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• 2009

In field of environments, the control and monitoring devices for sewage disposal facilities have been developed to overcome a problem of the water contamination according to industrialization and urbanization. In order to control and monitor the driving motor and the surroundings states of the sewage disposal facilities installed in local stations, this paper presents the design method of efficient module system interconnected by internal network with serial interface. It is expected that the proposed method in this paper is able to provide the more adaptive and flexible design technique for the specification of condition and factors needed in the fast-changed environment market.

• Korean Journal of Bronchoesophagology
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• v.7 no.2
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• pp.128-139
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• 2001

The purpose of this study was to review the literatures of experimental tracheal reconstruction. Although there have been significant advancements in the surgical treatment of the long circumferential tracheal injuries, there still has been a difficult problem with high morbidity and mortality. The method for tracheal reconstruction after circumferential resection is preferred end-to-end anastomosis for defects up to 6 cm in length, but larger tracheal defects require the use of tracheal allograft, various artificial prosthesis or autogenous organs. The tracheal allotransplantation has been widely used as there was significantly improved the method of surgical technique, preservation and immunosuppression. But it has been limited by a number of factors such as few donor, limited use of immunosuppressant, delayed revascularization and re-epitheliazation. Experimental studies on the tracheal prosthesis have a long history and they tried to use silicone, polytetrafluoroethylene, polypropylene mesh, Dacron, Marlex mesh, external or internal stents. Other experimental studies were reported the use of autogenous tissues that were cartilage. jejunum, aorta, skin, muscle, periostium or esophagus. But a great variety of these protheses have been resulted unsatisfactory in a significant Proportion of cases. Alternatively, the tissue-engineering technique has showed a new approach to reconstruct trachea and much progress in tissue-engineering bas been made recently. In conclusion, although the tracheal allotransplantation and the use of prosthesis and allograft have been reported a lot of limitation to overcome, we could sooner expect good result of ideal tracheal prosthesis.

• Journal of Aerospace System Engineering
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• v.14 no.2
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• pp.50-56
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• 2020

In this study, we investigated whether long short-term memory (LSTM) can be used in the future to predict F10.7 index data; the F10.7 index is a space environment factor affecting atomic oxygen erosion. Based on this, we compared the prediction performances of LSTM, the Autoregressive integrated moving average (ARIMA) model (which is a traditional statistical prediction model), and the similar pattern searching method used for long-term prediction. The LSTM model yielded superior results compared to the other techniques in the prediction period starting from the max/min points, but presented inferior results in the prediction period including the inflection points. It was found that efficient learning was not achieved, owing to the lack of currently available learning data in the prediction period including the maximum points. To overcome this, we proposed a method to increase the size of the learning samples using the sunspot data and to upgrade the LSTM model.

• Research in Plant Disease
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• v.19 no.2
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• pp.114-117
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• 2013

To facilitate their spread, plant viruses have developed several methods for dispersal including insect and seed transmission. While insect transmission requires virus stability against insect digestion, seed-transmitted viruses have to overcome barriers to entry into embryos. Bean pod mottle virus (BPMV) is transmitted through seed at levels typically below 0.1%, but co-infection with Soybean mosaic virus (SMV) enhanced the seed transmission rate of BPMV in one experiment. In contrast, the rate of SMV seed transmission was not affected by BPMV co-infection. In a second preliminary study, the rate of SMV transmission was lower in an isoline of Williams 82 that contained a null mutation for the Kunitz trypsin inhibitor gene than in Williams 82. In this preliminary study, we observed that factors such as protease inhibitor expression and dual infection may affect the frequency of seed transmission of BPMV and SMV.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.24 no.1
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• pp.171-187
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• 2013

The purpose of this study for coming up with vitalization methods of small libraries by attracting corporate donations, in order to overcome inferior financial circumstances of small libraries in daily life that play a role community centers in regional communities. For this, a frequency analysis was conducted in order to examine various circumstances and cognitions regarding library donations from 100 corporations that made donations during the past year. Also, a cross-tabulation analysis was studied to identify factors that influence donations.

• Journal of Ocean Engineering and Technology
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• v.22 no.6
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• pp.95-99
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• 2008

The block assembly of ship consists of a certain type of heat processes such as cutting, bending welding residual stress relaxation and fairing. The residual deformation due to welding is inevitable at each assembly stage. The geometric inaccuracy caused by the welding deformation tends to preclude the introduction of automation and mechanization and needs the additional man-hours for the adjusting work at the following assembly stage. To overcome this problem, a distortion control method should be applied. For this purpose, it is necessary to develop an accurate prediction method which can explicitly account for the influence of various factors on the welding deformation. The validity of the prediction method must be also clarified through experiments. This paper proposes a simplified analysis method to predict the welding deformation of panel block structure. For this purpose, a simple prediction model for fillet welding deformations has been derived based on numerical and experimental results through the regression analysis. On the basis of these results, the simplified analysis method has been applied to some examples to show its validity.