Search

In this paper, we discuss the upper semi-continuity of the solution to parameterη-Set-valued weak vector variational inequality problem. We show that the operator of parameterη-Set-valued weak vector variational inequality is not continuous, but it satisfiesν-semicontinuous andη-weakCpseudo-monotone. Our results generalize the previous results in the literature.

The dynamic compliance characteristics of a prosthetic foot midgait are very important for natural performance in an amputee’s gait and should be in a range that provides natural, stable walking. In this study, finite element analysis (FEA) and classical laminate theory were used to examine the mechanical characteristics of a carbon-epoxy composite laminate prosthetic foot as a function of variation in the lamination composition. From this analysis, an FEM model of a prosthetic keel, made from the composite material, was developed. The lamination composition of the keel was designed for improved stiffness. The prototype product was fabricated using an autoclave. Vertical loading response tests were performed to verify the simulation model. The results of the experiments were similar to those from simulations below the loading level of the gait, suggesting use of the proposed simulation model for prosthetic keel design.

In this paper, we propose a secure handoff scheme for data transmission in integration of 3G and 802.11 wireless local area networks (WLANs). The handoff between 802.11 WLAN and the 3G suffers from some drawbacks and has been hijacked through the middle of a communication session. We propose an architecture based on cloud computing to build our scheme to fix the problems in such heterogeneous wireless networks. Adaptive Key Exchange Protocol is proposed to protect data transmission as 3G users hand over to an 802.11 WLAN. The approach includes three phases, and all steps of each phase are protected by robust public-key encryption. Therefore, no information can be hijacked in such environment. The security analysis shows that data transmission between 802.11 WLAN and 3G is robust and secure in various aspects. Copyright © 2012 John Wiley & Sons, Ltd.

Aim To evaluate the efficacy of the three-dimensional (3D) Strabismus Photo Analyzer for estimating binocular alignment using photographs. Methods Thirty-two subjects with exotropia, 30 subjects with esotropia and 38 orthotropic subjects were included. Two independent ophthalmologists examined the angle of deviation using the Krimsky test and prism and alternate cover test (PCT). Full-face photographs were obtained using an 8.2-megapixel digital single-lens reflex camera, and the images were analysed using the 3D Strabismus Photo Analyzer. The images were adjusted for age-dependent ophthalmic biometry and angle κ. The main outcome measures were inter-observer variability, test‐retest reliability and correlation between the angles of deviation measured by different methods. Results The 95% limit of agreement of inter-observer variability was ±3.5° (6.1 prism dioptres (PD)), ±3.1° (5.4 PD) and ±1.5° (2.6 PD) for the Krimsky test, PCT and the 3D Strabismus Photo Analyzer, respectively. The test‐retest reliability was ±2.8° (4.9 PD) for the 3D Strabismus Photo Analyzer versus the Krimsky test. The results of the Krimsky test and 3D Strabismus Photo Analyzer showed a strong positive correlation. Conclusions The 3D Strabismus Photo Analyzer is a simple and reliable tool for measuring ocular deviation. It has excellent agreement with the Krimsky test and substantially improved reproducibility.

The primary purpose of this study was to analyze the motion of the scaphoid, capitate, and lunate during dart-throwing motion by three-dimensional modeling. Five series of CT images of five normal right wrists were acquired from five motion steps from radial extension to ulnar flexion in the dart-throwing motion plane. Segmentation and three-dimensional modeling of bones from CT images was performed using Analyze. Distances among centroids of the scaphoid, capitate and lunate and angles between principal axes of three carpal bones were calculated to analyze the motion by using MATLAB. As the wrist motion changed from radial extension to ulnar flexion, the distance between two adjacent bones decreased. The scaphoid and lunate rotated less than the capitates during dart-throwing motion. This study reports the Three-dimensional in vivo measurement of carpal motion using CT images.

Image processing of a fundus image is performed for the early detection of diabetic retinopathy. Recently, several studies have proposed that the use of a morphological filter may help extract hemorrhages from the fundus image; however, extraction of hemorrhages using template matching with templates of various shapes has not been reported. In our study, we applied hue saturation value brightness correction and contrast-limited adaptive histogram equalization to fundus images. Then, using template matching with normalized cross-correlation, the candidate hemorrhages were extracted. Region growing thereafter reconstructed the shape of the hemorrhages which enabled us to calculate the size of the hemorrhages. To reduce the number of false positives, compactness and the ratio of bounding boxes were used. We also used the 5 × 5 kernel value of the hemorrhage and a foveal filter as other methods of false positive reduction in our study. In addition, we analyzed the cause of false positive (FP) and false negative in the detection of retinal hemorrhage. Combining template matching in various ways, our program achieved a sensitivity of 85% at 4.0 FPs per image. The result of our research may help the clinician in the diagnosis of diabetic retinopathy and might be a useful tool for early detection of diabetic retinopathy progression especially in the telemedicine.

This paper describes the development and implementation of a algorithm to decompose word images from image regions mixed text/graphics in document images using statistical analyses. To decompose word images from image regions, the character components need to be separated from graphic components. For this process, we propose a method to separate them with an analysis of box-plot using a statistics of structural components. An accuracy of this method is not sensitive to the changes of images because the criterion of separation is defined by the statistics of components. And then the character regions are determined by analyzing a local crowdedness of the separated character components. finally, we devide the character regions into text lines and word images using projection profile analysis, gap clustering, special symbol detection, etc. The proposed system could reduce the influence resulted from the changes of images because it uses the criterion based on the statistics of image regions. Also, we made an experiment with the proposed method in document image processing system for keyword spotting and showed the necessity of studying for the proposed method.

Whole-body bone scan is one of the most frequent diagnostic procedures in nuclear medicine. Especially, it plays a significant role in important procedures such as the diagnosis of osseous metastasis and evaluation of osseous tumor response to chemotherapy and radiation therapy. It can also be used to monitor the possibility of any recurrence of the tumor. However, it is a very time-consuming effort for radiologists to quantify subtle interval changes between successive whole-body bone scans because of many variations such as intensity, geometry, and morphology. In this paper, we present the most effective method of image enhancement based on histograms, which may assist radiologists in interpreting successive whole-body bone scans effectively. Forty-eight successive whole-body bone scans from 10 patients were obtained and evaluated using six methods of image enhancement based on histograms: histogram equalization, brightness-preserving bi-histogram equalization, contrast-limited adaptive histogram equalization, end-in search, histogram matching, and exact histogram matching (EHM). Comparison of the results of the different methods was made using three similarity measures peak signal-to-noise ratio, histogram intersection, and structural similarity. Image enhancement of successive bone scans using EHM showed the best results out of the six methods measured for all similarity measures. EHM is the best method of image enhancement based on histograms for diagnosing successive whole-body bone scans. The method for successive whole-body bone scans has the potential to greatly assist radiologists quantify interval changes more accurately and quickly by compensating for the variable nature of intensity information. Consequently, it can improve radiologists’ diagnostic accuracy as well as reduce reading time for detecting interval changes.

We propose a security authentication policy, Dynamic Session Key Policy (DSKP), for a secure handoff between the UMTS and IEEE 802.11 WLAN. This policy is founded and improved from Dynamic Key Exchange Protocol (DKEP). It redeems the confidentiality of the communication association using the asymmetric and symmetric encryption. The one time password system is used for the key exchange of the sessions. The transition of the communication states in DSKP are seamless and cannot be personated. From the security analysis, using the DSKP can avoid possible attack in wireless circumstance. EAP-SIM and EAP-AKA, commonly used for authentication protocol in present WLAN, were also studied to compare with DSKP. From our security analysis, DSKP shows better security grades.

A lot of printed documents and books has been published and saved as a form of images in digital libraries. Searching for a specified query word on document images is a challenging problem. The OCR software helps the images to be converted to the machine readable documents to search a full context [1]. Another approach [1, 2] is image-based one, in which both the document images and word information are saved in a database. The searching procedure is accomplished through comparing the features of query word image with the word images extracted from document images in the database. In this paper, we propose an accurate and fast keyword spotting system for searching user-specified keyword in Hangul document images by a two-level image-to-image matching method.

This paper presents a system for the segmentation of a printed document image into word images, which can be used effectively for document image retrieval based on keyword spotting. The system is composed of three image manipulation modules: skew correction, document layout analysis, and word segmentation. To enhance the practical applicability and flexibility of our research results, we test the system with 50 images of Korean papers and 50 images of English papers provided through full-text image retrieval services by the Korea Information Science Society and the Pattern Recognition Society, respectively. Currently, the accuracy of word extraction ranges from 90 to 95%, depending on the language of the document.

This paper proposes a system for the extraction of typographical attributes, such as font style and typeface, that can be used to improve the performance of OCR and keyword spotting technologies on printed Korean document images. Three typographical features have been devised and experimented with 7,200 Korean word images. The individual accuracies for font style identification and typeface identification are 97.2% and 99.1%, respectively.