• Computers and Concrete
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• v.15 no.3
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• pp.461-471
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• 2015

The permeability is the most direct indicator to reflect the durability of concrete, and the testing methods based on external electric field can be used to evaluate concrete permeability rapidly. This study aims to use an experiment method to accurately predict the permeability of concrete box beam during service. The ion migration experiments and concrete surface resistivity are measured to evaluate permeability of five concrete box beams, and the relations between these results in service concrete and electric flux after 6 hours by ASTM C1202 in the laboratory are analyzed. The chloride diffusion coefficient of concrete, concrete surface resistivity and concrete 6 hours charge have good correlation relationship, which denote that the chloride diffusion coefficient and the surface resistivity of concrete are effective for evaluating the durability of concrete structures. The chloride diffusion coefficient of concrete is directly evaluated permeability of concrete box beam in service and may be used to predict the service life, which is fit to engineering applications and the concrete box beam is non-destructive. The concrete surface resistivity is easier available than the chloride diffusion coefficient, but it is directly not used to calculate the service life. Therefore the mathematical relation of the concrete surface resistivity and the concrete chloride diffusion coefficient need to be found, which the service life of reinforced concrete is obtained by the concrete surface resistivity.

• Structural Engineering and Mechanics
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• v.65 no.5
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• pp.601-609
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• 2018

Steel bolts are used in the construction industry for a large variety of applications that range from fixing permanent installations to temporary fixtures. In the past much research has been focused on developing destructive testing techniques to estimate their pull-out load carrying capacity with very little attention to develop non-destructive techniques. In this regards the presented research work details the combined use of ultrasonic pulse velocity and Schmidt hammer tests to identify anchor bolts with faculty installation and to estimate their pull-out strength by relating it to the Schmidt hammer rebound value. From experimentation, it was observed that the load capacity of bolt depends on its embedment length, diameter, bond quality/concrete strength and alignment. Ultrasonic pulse velocity test is used to judge the quality of bond of embedded anchor bolt by relating the increase in ultrasonic pulse transit time to the presence of internal pours and cracks in the vicinity of steel bolt and the surrounding concrete. This information combined with the Schmidt hammer rebound number, R, can be used to accurately identify defective bolts which resulted in lower pull-out strength. 12 mm diameter bolts with embedment length of 70 mm and 50 mm were investigated using constant strength concrete. Pull-out load capacity versus the Schmidt hammer rebound number for each embedment length is presented.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.6
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• pp.447-456
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• 2014

In this paper, a new damage-detection method based on structural vibration is proposed. The essence of the proposed method is the detection of abrupt changes in rotation. Damage-induced rotation (DIR), which is determined from the modal flexibility of the structure, initially occurs only at a specific damaged location. Therefore, damage can be localized by evaluating abrupt changes in rotation. We conducted numerical simulations of two damage scenarios using a 10-story cantilever-type building model. Measurement noise was also considered in the simulation. We compared the sensitivity of the proposed method to localize damage to that of two conventional modal-flexibility-based damage-detection methods, i.e., uniform load surface (ULS) and ULS curvature. The proposed method was able to localize damage in both damage scenarios for cantilever structures, but the conventional methods could not.

• The International Journal of Costume Culture
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• v.4 no.3
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• pp.241-248
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• 2001

Re water resistance of shell fabrics intended for we in outdoor apparel was measured using three different standard test methods, ASTM D 751, hydrostatic resistance, procedure A(Mullen test -- with and without a fabric support) and Procedure B (Hydrostatic head test). A database of information on their water resistance performance was created. The data collected with different methods were correlated and the advantages and disadvantages of each method were compared. The Mullen test with a support appears to give higher and more favorable water resistance values on shell fabrics preventing fabric rupture during the test. The hydrostatic head test gave lower hydrostatic pressure values than those measured on the two Mullen tests. The Mullen test is recommended for testing the water resistance of fabrics that high a relatively high water resistance because the Mullen tester applies a wide range of pressure. The hydrostatic head test is recommended for testing the fabrics that have relatively low water resistance. The area of the fabric sample that is in contact with the water is smaller in the Mullen test, so higher pressure levels can be reached and more samples should probably be tested to get a representative value for each fabric types. Furthermore, the hydrostatic head test was deemed more repeatable than the Mullen tests in his study.

• Biomaterials and Biomechanics in Bioengineering
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• v.3 no.2
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• pp.85-104
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• 2016

Stability and loosening of implanted femoral stems in Total Hip Replacement have been well established as barriers to the primary concerns of osseointegration and long term implant survival. In-vitro experiments and finite element modeling have for years been used as a primary tool to assess the bone stem interface with variable methodologies leading to a wide range of micromotion, interference fit and stress shielding values in the literature. The current study aims to provide a comprehensive review of currently utilized methodologies for in-vitro mechanical testing as well as finite element modeling of both micromotion and interference of implanted femoral stems. A total of 12 studies detailed in 33 articles were selected for inclusion. Experimental values of micromotion ranged from 12 to $182{\mu}m$ while finite element analysis reported a wider range from 2.74 to $1,277{\mu}m$. Only two studies were found that modeled bone/implant contact with consideration for interference fit. In studies evaluating stem micromotion in THA, the reference surface at the bone/stem interface should be well defined. Additionally, the amount of penetration considered should be disclosed and associated with bone density and roughness.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4665-4669
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• 2016

Purpose: To evaluate the legitimacy of a diagnosis of ASC-H in 5 cases which were followed up monthly for over 2 years with both cytology and HPV testing. Methods: Some 5 cases out of a total of 25.0 self-sampled Pap test patients diagnosed as ASC-H provided 119 specimens over 2 years, with HPV-DNA testing perormed using a E6 primer. Results: Cases 1, 2 and 3 showed SIL after the ASC-H diagnosis, while cases 4 and 5 showed and maintained NILM. Cases 1, 2 and 3 were further characterized by small atypical compressed binucleated cells, in which HPV was detected by in situ PCR. Case 4 showed a high N/C ratio in cells in sheets with a mild increase in chromatin. Case 5 demonstrated a high N/C ratio in small cells with no increase in chromatin. Conclusion: The finding of a compressed binucleated cells can define the difference between degenerated endocervical columnar cells and small atypical cells suggestive of HSIL. When small compressed binucleated squamous cells are detected, there may be a chance of continuing HPV infection and undetected SIL.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.3
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• pp.193-199
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• 2015

Active thermography techniques have the capability of inspecting a broad range simultaneously. By evaluating the phase difference between the defected area and the healthy area, the technique indicates the qualitative location and size of the defect. Previously, the development of the defect detection method used a variety of materials and the test specimen was done. In this study, the proposed technique of lock-in is verified with artificial specimens that have different size and depth of subsurface defects. Finally, the defect detection capability was evaluated using comparisons of the phase image and the amplitude image according to the size and depth of defects.

• Korean Medical Education Review
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• v.16 no.1
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• pp.11-15
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• 2014

A number of medical schools in Korea have been using computer-based testing (CBT) for evaluating their students' scientific and/or clinical performance since the early 1990s. Introducing CBT to medical education would have several advantages: first, presenting figures and audio-video files of clinical content is simple with CBT, making it possible to evaluate medical students' competency with navigating more realistic clinical situations at minimum cost; second, CBT enables automatic item analysis and score reporting. To establish CBT, constructing an item bank with item parameters such as difficulty or discriminating parameters will be needed. To select more psychometrically sound items, analysis of the items according to item response theory is necessary. CBT has already been introduced in high stakes tests like the United States Medical Licensing Examination and the Medical Council of Canada Qualifying Examination. The National Health Personnel Examination Board in Korea is also planning to introduce a CBT-based version of the National Medical Examination soon. Thus all medical schools in Korea will need to introduce CBT and construct item banks to prepare their students for their licensing examinations and to measure the students' competency more accurately.

• International Journal of Computer Science & Network Security
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• v.21 no.9
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• pp.51-62
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• 2021

Plant disease is one of the issues that can create losses in the production and economy of the agricultural sector. Early detection of this disease for finding solutions and treatments is still a challenge in the sustainable agriculture field. Currently, image processing techniques and machine learning methods have been applied to detect plant diseases successfully. However, the effectiveness of these methods still needs to be improved, especially in multiclass plant diseases classification. In this paper, a convolutional neural network with a batch normalization-based deep learning approach for classifying plant diseases is used to develop an automatic diagnostic assistance system for leaf diseases. The significance of using deep learning technology is to make the system be end-to-end, automatic, accurate, less expensive, and more convenient to detect plant diseases from their leaves. For evaluating the proposed model, an experiment is conducted on a public dataset contains 20654 images with 15 plant diseases. The experimental validation results on 20% of the dataset showed that the model is able to classify the 15 plant diseases labels with 96.4% testing accuracy and 0.168 testing loss. These results confirmed the applicability and effectiveness of the proposed model for the plant disease detection task.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.69-77
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• 2014

Because smart televisions (TVs) have various and innovative functions that are different from traditional TVs, consumers are front with a complex decision-making problem when they want to buy a best TV among alternatives made by many TV makers. TV manufactures have developed and announced different types of smart TV models and they need a comparative study for evaluating their characteristics. In this paper, we suggest the Analytic Hierarchy Process(AHP) method for deciding the best smart TVs regarding many selection criteria. The method provides a decision support for consumers who like to purchase a smart TV. We describe criteria affecting the smart TV selection through a literature review and suggest a user testing method in order to derive accurate judgments from consumers. Using the Expert Choice software package, we show a an numerical example how the priority of smart TVs are computed.