• Progress in Superconductivity
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• v.1 no.2
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• pp.110-114
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• 2000

We have investigated the Josephson vortex dynamics in $Bi_2Sr_2CaCu_2O{8+\delta}$ intrinsic Josephson junctions subjected to a magnetic field parallel to $CuO_2$ planes. We investigated mesas with $40\times40{\mu}m^2$ in size and containing 6 and 20. intrinsic junctions. The zero field I-V characteristics exhibited a typical hysteretic, multi-branched nature of the intrinsic Josephson effect. At high magnetic fields (H>1.5 T), I-V characteristics showed flux flow steps. The Swihart velocity obtained from this observation was about $4.2\times10^5$ m/s, which was the lowest mode electromagnetic wave velocity of N coupled stack. The experimental I-V curves fitted well into the simple model of Cherenkov radiation including Ohmic and non-linear dissipation terms. This suggests that the dissipation mechanism of Josephson vortex be due to both Cherenkov radiation and quasiparticle tunneling current.

• Smart Structures and Systems
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• v.17 no.6
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• pp.935-956
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• 2016

With the help of advanced image acquisition and processing technology, the vision-based measurement methods have been broadly applied to implement the structural monitoring and condition identification of civil engineering structures. Many noncontact approaches enabled by different digital image processing algorithms are developed to overcome the problems in conventional structural dynamic displacement measurement. This paper presents three kinds of image processing algorithms for structural dynamic displacement measurement, i.e., the grayscale pattern matching (GPM) algorithm, the color pattern matching (CPM) algorithm, and the mean shift tracking (MST) algorithm. A vision-based system programmed with the three image processing algorithms is developed for multi-point structural dynamic displacement measurement. The dynamic displacement time histories of multiple vision points are simultaneously measured by the vision-based system and the magnetostrictive displacement sensor (MDS) during the laboratory shaking table tests of a three-story steel frame model. The comparative analysis results indicate that the developed vision-based system exhibits excellent performance in structural dynamic displacement measurement by use of the three different image processing algorithms. The field application experiments are also carried out on an arch bridge for the measurement of displacement influence lines during the loading tests to validate the effectiveness of the vision-based system.

• Smart Structures and Systems
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• v.18 no.3
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• pp.585-599
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• 2016

Steel cables serve as the key structural components in long-span bridges, and the force state of the steel cable is deemed to be one of the most important determinant factors representing the safety condition of bridge structures. The disadvantages of traditional cable force measurement methods have been envisaged and development of an effective alternative is still desired. In the last decade, the vision-based sensing technology has been rapidly developed and broadly applied in the field of structural health monitoring (SHM). With the aid of vision-based multi-point structural displacement measurement method, monitoring of the tensile force of the steel cable can be realized. In this paper, a novel cable force monitoring system integrated with a multi-point pattern matching algorithm is developed. The feasibility and accuracy of the developed vision-based force monitoring system has been validated by conducting the uniaxial tensile tests of steel bars, steel wire ropes, and parallel strand cables on a universal testing machine (UTM) as well as a series of moving loading experiments on a scale arch bridge model. The comparative study of the experimental outcomes indicates that the results obtained by the vision-based system are consistent with those measured by the traditional method for cable force measurement.

• Asian Journal of Business Environment
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• v.11 no.2
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• pp.27-38
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• 2021

Purpose: The study mainly investigates bankruptcy risk and income smoothing tendency of Non-Banking Financial Institutions (NBFIs) in Bangladesh. External parties of NBFIs take investment decisions based on financial reports. Stable and predictable income is one of their preference. On the other hand, poor income is one of the signs of NBFIs having bankruptcy risk. Hence the study tries to find whether the NBFIs having bankruptcy are involved in income smoothing or not. Research design, data and methodology: Data were collected from the annual report of twenty-two listed NBFIs in Bangladesh. Data from 2013 to 2017 were used. Altman's Z score and Eckel's model are used to detecting bankruptcy risk and income smoothing respectively. Results: Result implies that most of the NBFIs which have bankruptcy risk are not involved in income smoothing. Therefore, NBFIs which has bankruptcy risk are involved less with income smoothing. Conclusions: The present study revealed that most of the listed NBFIs in Bangladesh are facing bankruptcy risk. They didn't use any fraudulent technique to show smooth income. The findings will help the investor to take an investment decision on NBFIs in Bangladesh. It will convey signals to the stock market in Bangladesh.

• Smart Structures and Systems
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• v.29 no.1
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• pp.141-151
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• 2022

In recent years, the industry and research communities have focused on developing autonomous crack inspection approaches, which mainly include image acquisition and crack detection. In these approaches, mobile devices such as cameras, drones or smartphones are utilized as sensing platforms to acquire structural images, and the deep learning (DL)-based methods are being developed as important crack detection approaches. However, the process of image acquisition and collection is time-consuming, which delays the inspection. Also, the present mobile devices such as smartphones can be not only a sensing platform but also a computing platform that can be embedded with deep neural networks (DNNs) to conduct on-site crack detection. Due to the limited computing resources of mobile devices, the size of the DNNs should be reduced to improve the computational efficiency. In this study, an architecture called pruned crack recognition network (PCR-Net) was developed for the detection of structural cracks. A dataset containing 11000 images was established based on the raw images from bridge inspections. A pruning method was introduced to reduce the size of the base architecture for the optimization of the model size. Comparative studies were conducted with image processing techniques (IPTs) and other DNNs for the evaluation of the performance of the proposed PCR-Net. Furthermore, a modularly designed framework that integrated the PCR-Net was developed to realize a DL-based crack detection application for smartphones. Finally, on-site crack detection experiments were carried out to validate the performance of the developed system of smartphone-based detection of structural cracks.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.4
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• pp.297-308
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• 2003

Face-bow is used to transfer models to the articulator in diagnosing the patient or treating problems associated with occlusion. However, there have been few reports on the reliability of the face-bow procedure and the relationship between the experience of the operator and the reliability of the face-bow procedure. The purposes of this study are to examine the reliability of the face-bow procedure and to evaluate whether the face-bow transferring has any training effect. Nine dentists working at M hospital conducted a face-bow transfer in one patient having a normal dentition and interdental relationship. The procedure was done two times a week for four weeks. The maxillary model was mounted to the articulator every time, then the landmarks on the maxillary right first molar, the maxillary left central incisor, and the maxillary left first molar were measured with a special three-dimensional instrument. These data were input into a computer, and evaluated statistically. The results were as follows ; 1. When examined with ANOVA test, the results were p=0.2040 in maxillary right first molar, p=0.0578 in maxillary left incisor, and p=0.1433 in maxillary left first molar. There was no significant(0< $p{\leq}0.05$). 2. Training 1) The correlation coefficient between trial and rejection was -0.578 when analyzed with T-distribution. The more we tried, the less errors we found. 2) When the S.D. of the first three trials was compared to the S.D. of the last three trials in face-bow transfer, the results showed that the former was larger than the latter in thirty-nine times, and the latter was larger than the former in fifteen times. The more we tried face-bow transfer, the less errors we found. 3. When the S.D. of x, y, z coordinates were examined, the S.D. of x coordinates had the largest measurement in five times, the S.D. of y coordinates had the largest measurement in four times, and the S.D. of z coordinates had the largest measurement in nine times. The possibility which the error can occur in z coordinate was the highest.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.4 no.2
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• pp.77-87
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• 1986

As for the deformation measurement of structure, there are many controversial points in using the methods by the strain guage, inclinometer, bial guage, and geodetic method because of the difficulty of instrument setting and the problem in the degree of accuracy of the results as well as in the economical aspect. Therefore, to verify the superiority of the Close- Range Photogrammetry method for the structural deformation measurement, the result of load deformation on the model structure, which was made using the Close-Range Photogrammetry method was compard with the results which was made using the methods of dial guage, precision level, and triangulation. In addition to that, to consider the general problem which would happen when C. R. P method was applied to the practical structure. The elements of C. R. P method like camera rotation angle ($\psi$,$\omega$), exposure elevation (Z$_{L}$), and angle of inclined base line ($\theta$) were experimented, and their specificities were reconsidered. As a result, the application of C. R. P method to the general structure is expected to be increased not only in the aspect of accuracy but in the economical aspect.t.

• Journal of Biomedical Engineering Research
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• v.23 no.3
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• pp.197-205
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• 2002

The objectives of this Paper is to implement a diagnostic classifier of differential laryngeal diseases from acoustic signals acquired in a noisy room. For this Purpose, the voice signals of the vowel /a/ were collected from Patients in a soundproof chamber and got mixed with noise. Then, the acoustic Parameters were analyzed, and hierarchical neural networks were applied to the data classification. The classifier had a structure of five-step hierarchical neural networks. The first neural network classified the group into normal and benign or malign laryngeal disease cases. The second network classified the group into normal or benign laryngeal disease cases The following network distinguished polyp. nodule. Palsy from the benign laryngeal cases. Glottic cancer cases were discriminated into T1, T2. T3, T4 by the fourth and fifth networks All the neural networks were based on multilayer perceptron model which classified non-linear Patterns effectively and learned by an error back-propagation algorithm. We chose some acoustic Parameters for classification by investigating the distribution of laryngeal diseases and Pilot classification results of those Parameters derived from MDVP. The classifier was tested by using the chosen parameters to find the optimum ones. Then the networks were improved by including such Pre-Processing steps as linear and z-score transformation. Results showed that 90% of T1, 100% of T2-4 were correctly distinguished. On the other hand. 88.23% of vocal Polyps, 100% of normal cases. vocal nodules. and vocal cord Paralysis were classified from the data collected in a noisy room.

• The Korean Nurse
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• v.32 no.5
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• pp.66-77
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• 1994

The purpose of this study was to develop a new nursing unit which can meet changing health care needs, enhance patients' satisfaction and nurses' job satisfaction, and finally guarantee quality nursing care with present manpower. For this, one medical unit was selected as a unit for quality care. And one medical unit which is similar in staffing and patients' characteristics was selected as a control unit. To assess present problems and identify the remedies to the problems a hospital-wide survey and a workshop were performed. According to the survey results, educational programs and improvement of the facilities and equipment supply system, managereal support for interdepartmental cooperation and intensification of bed-side nursing care were adopted as main principles for operating model unit, This model unit was operated for 3 months from Sep. 1, 1992 to Nov. 30, 1992. To evaluate the effectiveness of the model unit, derect/indirect nursing care hours, patients' satisfaction to nursing care, nurses' job satisfaction, and quality care index were measured. Direct/indirect nursing care hours were compared with that of the control unit, and patients' and nurses' satisfaction and quality care index were measured before and after operating model unit and compared with each other. The results of the study were as follows; 1. In the model unit mean direct nursing care hours per cach shift was 146.88 minutes and indirect nursing care hours was 354.72 minutes. The ratio of the direct nursing care hour to indirect nursing hour was 29.6 ; 70.4 and that of the control unit was 26.9 : 73.1. Direct nursing care hour in model unit was longer than that of the control unit. But, the difference was not significant. In subcategories of direct nursing care, the time spent in mobility and exercise, conservation of body temperature, hygiene, and communication and health education were longer than that of the con" trol unit. 2. Indirect nursing care hour in model unit was shorter than that of the control unit. But, the difference was not significant. In subcategories of indirect nursing care, the time spent in drug management and ward arrangement was shorter than that of the control unit. 3. Patients' satisfaction to nursing care was increased significantly after operating the model unit (T=-3.48, P=-0.002) and satisfaction to subcategories of physical comfort measure, psychological cate, and unit management components were significantly higher than before. 4. In the model unit, nurses' total job satisfaction was increased significantly after operating the model unit(Z=2.1004, P=.0357) and satisfaction to subcategory of satisfaction to administration was significantly higher than before (Z=-2.0732, P=.0382). 5. After operating the model unit, quality care index was increased from 89 to 93. With this results, it can be summarized that all the measures tried for quality care, such as educational programs, managereal support for interdepartmental cooperation, and improvement of the equipment and facility provision resulted in partial increase in direct nursing care hours, nurses satisfaction to their job and patients' satisfaction to nursing care. In can be postulated that managereal support and motivation without proper staff supplementation is not enough for increasing direct nursing care hours. And for the enhancement of the level in clinical nursing, and staff supplement must be considered sincerely and the measures for reducing indirect nursing care hours, such as computerization of nursing care activities, improvement of facilities and equipment and facilities supply system, must be instituted in addition.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.556-566
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• 2022

The temperature-dependent development of Poinsettia thrips, Echinothrips americanus was studied at eight constant temperatures (15.0, 17.5, 20.0, 22.5, 25.0, 27.5, 30.0, and 32.5±1℃), 65±5% RH and photoperiod of 16L:8D conditions. The developmental stages were divided into egg, 1st instar, 2nd instar, pre-pupa, pupa, and adult. The total developmental time in the immature stage was 40.4 days at 15.0℃ and 11.6 days at 30.0℃, and it decreased with increasing temperature. The lowest temperature of the whole immature period was 10.7℃, and the cumulative temperature to complete the entire immature period was 217.4 degree days. The optimal development temperature (T_opt) for the whole immature stage was estimated to be in the range of 30.51-31.21℃. T_opt for each immature stage was 31.64-35.47℃ at egg, 30.02-33.08℃ at 1st instar, 29.16-34.43℃ at 2nd instar, 27.63-29.21℃ at pre-pupa, and 29.81-30.12℃ at pupa. In the analysis of the six non-linear models, Logan 6 model was the most appropriate as Zi(Weighting Factors) was 0.18.