• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.2
• /
• pp.412-434
• /
• 2023

This study discusses the high-order diffusion method in the wavelet domain. It aims to improve the edge protection capability of the high-order diffusion method using wavelet coefficients that can reflect image information. During the first step of the proposed diffusion method, the wavelet packet decomposition is a more refined decomposition method that can extract the texture and structure information of the image at different resolution levels. The high-frequency wavelet coefficients are then used to construct the edge detection function. Subsequently, because accurate wavelet coefficients can more accurately reflect the edges and details of the image information, by introducing the idea of state weight, a scheme for recovering wavelet coefficients is proposed. Finally, the edge detection function is constructed by the module of the wavelet coefficients to guide high-order diffusion, the denoised image is obtained. The experimental results showed that the method presented in this study improves the denoising ability of the high-order diffusion model, and the edge protection index (SSIM) outperforms the main methods, including the block matching and 3D collaborative filtering (BM3D) and the deep learning-based image processing methods. For images with rich textural details, the present method improves the clarity of the obtained images and the completeness of the edges, demonstrating its advantages in denoising and edge protection.

• Journal of Korea Society of Industrial Information Systems
• /
• v.15 no.1
• /
• pp.37-46
• /
• 2010

A Suffix Tree is an efficient data structure that exposes the internal structure of a string and allows efficient solutions to a wide range of complex string problems, in particular, in the area of computational biology. However, as the biological information explodes, it is impossible to construct the suffix trees in main memory. We should find an efficient technique to construct the trees in a secondary storage. In this paper, we present a method for constructing a suffix tree in a disk for large set of DNA strings using new index scheme. We also show a typical application example with a suffix tree in the disk.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.47 no.3
• /
• pp.75-85
• /
• 2024

Airpower is a crucial force for suppressing military threats and achieving victory in wars. This study evaluates newly introduced fighter forces, considering factors such as fighter performance and power index, operational environment, capacity of each airbase, survivability, and force sustainment capability to determine the optimal deployment plan that maximizes operational effectiveness and efficiency. Research methods include optimization techniques such as MIP(mixed integer programming), allocation problems, and experimental design. This optimal allocation mathematical model is constructed based on various constraints such as survivability, mission criticality, and aircraft's performance data. The scope of the study focuses the fighter force and their operational radius is limited to major Air Force and joint operations, such as air interdiction, defensive counter-air operations, close air support, maritime operations and so on. This study aims to maximize the operational efficiency and effectiveness of fighter aircraft operations. The results of proposed model through experiments showed that it was for superior to the existing deployment plan in terms of operation and sustainment aspects when considering both wartime and peacetime.

• The Journal of Society for e-Business Studies
• /
• v.15 no.3
• /
• pp.131-145
• /
• 2010

Until now, popular paradigms to provide e-catalog documents that are adapted to users' needs are keyword search or collaborative filtering based recommendation. Since users' queries are too short to represent what users want, it is hard to provide the users with e-catalog documents that are adapted to their needs(i.e., queries and preferences). Although various techniques have beenproposed to overcome this problem, they are based on index term matching. A conventional Bayesian belief network-based approach represents the users' needs and e-catalog documents with their corresponding concepts. However, since the concepts are the index terms that are extracted from the e-catalog documents, it is hard to represent relationships between concepts. In our work, we extend the conventional Bayesian belief network based approach to represent users' needs and e-catalog documents with a concept network which is derived from the Web directory. By exploiting the concept network, it is possible to search conceptually relevant e-catalog documents although they do not contain the index terms of queries. Furthermore, by computing the conceptual similarity between users, we can exploit a semantic collaborative filtering technique for recommending e-catalog documents.

• Journal of KIISE
• /
• v.42 no.1
• /
• pp.97-106
• /
• 2015

Recently, research on database encryption for data protection and query result authentication methods has been performed more actively in the database outsourcing environment. Existing database encryption schemes are vulnerable to order matching and counting attack of intruders who have background knowledge of the original database domain. Existing query result integrity auditing methods suffer from the transmission overhead of verification object. To resolve these problems, we propose a group-order preserving encryption index and a query result authentication method based on the encryption index. Our group-order preserving encryption index groups the original data for data encryption and support query processing without data decryption. We generate group ids by using the Hilbert-curve so that we can protect the group information while processing a query. Finally, our periodic function based data grouping and query result authentication scheme can reduce the data size of the query result verification. Through performance evaluation, we show that our method achieves better performance than an existing bucket-based verification scheme, it is 1.6 times faster in terms of query processing time and produces verification data that is 20 times smaller.

• Journal of Gastric Cancer
• /
• v.18 no.3
• /
• pp.230-241
• /
• 2018

Purpose: Enhanced recovery after surgery (ERAS) protocols for gastric cancer patients have shown improved outcomes in Asia. However, data on gastric cancer ERAS (GCERAS) programs in the United States are sparse. The purpose of this study was to compare perioperative outcomes before and after implementation of an GC-ERAS protocol at a National Comprehensive Cancer Center in the United States. Materials and Methods: We reviewed medical records of patients surgically treated for gastric cancer with curative intent from January 2012 to October 2016 and compared the GC-ERAS group (November 1, 2015-October 1, 2016) with the historical control (HC) group (January 1, 2012-October 31, 2015). Propensity score matching was used to adjust for age, sex, number of comorbidities, body mass index, stage of disease, and distal versus total gastrectomy. Results: Of a total of 95 identified patients, matching analysis resulted in 20 and 40 patients in the GC-ERAS and HC groups, respectively. Lower rates of nasogastric tube (35% vs. 100%, P<0.001) and intraabdominal drain placement (25% vs. 85%, P<0.001), faster advancement of diet (P<0.001), and shorter length of hospital stay (5.5 vs. 7.8 days, P=0.01) were observed in the GC-ERAS group than in the HC group. The GC-ERAS group showed a trend toward increased use of minimally invasive surgery (P=0.06). There were similar complication and 30-day readmission rates between the two groups (P=0.57 and P=0.66, respectively). Conclusions: The implementation of a GC-ERAS protocol significantly improved perioperative outcomes in a western cancer center. This finding warrants further prospective investigation.

• Clinics in Shoulder and Elbow
• /
• v.23 no.1
• /
• pp.11-19
• /
• 2020

Background: The purpose of this study was to evaluate and compare deltoid origin status following large rotator cuff repair carried out using either an open or an arthroscopic method with a propensity score matching technique. Methods: A retrospective review of 112 patients treated for full-thickness, large rotator cuff tear via either a classic open repair (open group) or an arthroscopic repair (arthroscopic group) was conducted. All patients included in the study had undergone postoperative magnetic resonance imaging (MRI) and clinical follow-up for at least 12 and 18 months after surgery, respectively. Propensity score matching was used to select controls matched for age, sex, body mass index, and affected site. There were 56 patients in each group, with a mean age of 63.3 years (range, 50-77 years). The postoperative functional and radiologic outcomes for both groups were compared. Radiologic evaluation for postoperative rotator cuff integrity and deltoid origin status was performed with 3-Tesla MRI. Results: The deltoid origin thickness was significantly greater in the arthroscopic group when measured at the anterior acromion (P=0.006), anterior third (P=0.005), and middle third of the lateral border of the acromion level (P=0.005). The deltoid origin thickness at the posterior third of the lateral acromion was not significantly different between the arthroscopic and open groups. The arthroscopic group had significantly higher intact deltoid integrity with less scarring (P=0.04). There were no full-thickness deltoid tears in either the open or arthroscopic group. Conclusions: Open rotator cuff repair resulted in a thinner deltoid origin, especially from the anterior acromion to the middle third of the lateral border of the acromion, at the 1-year postoperative MRI evaluation. Meticulous reattachment of the deltoid origin is as essential as rotator cuff repair when an open approach is selected.

• Journal of vocational education research
• /
• v.35 no.4
• /
• pp.63-88
• /
• 2016

This study surveyed and analyzed the labor market result when comparing the case that junior college students found a job after transferring to 4-year university with the case that they found the job directly after graduating the junior college. The difference of the occupational structure following the transfer was surveyed in detail and this study examined what effect the transfer had on the occupation status. The graduate occupation movement survey(GOMS) was used and the samples of 544 persons were extracted to use through propensity score matching(PSM) to raise the choice convenience of the sample. The occupation status index to use as a dependent variable was developed to apply. The study result is as follows. First, as a result of confirming the occupational structure of the transfer, the transfer students were distributed in more various industrial fields evenly compared to the non-transfer students in the horizontal industrial structure, and non-transfer students were intensively distributed in the certain field. In the vertical occupation status structure, transfer students were distributed in the high occupation status more than non-transfer students who were broadly distributed in the low occupation status. Second, it was revealed the college transfer was highly effective for the occupation status, which appeared statistically significantly. The explanation variable that appeared significantly outside of that included the parents' academic background, major affiliation, employment pattern, major job coincidence, and job coincidence. The higher students' academic background was, the higher the occupation status was and in case of the engineering natural science affiliation, the occupation status was higher than the humanities social science. In case of full-time workers, their occupation status was higher than one of part time workers and it was revealed the occupation status was high when the their major coincided with the job and their educational/technical level coincided with their job.

• Journal of KIISE:Databases
• /
• v.32 no.4
• /
• pp.383-393
• /
• 2005

Retrieval of images from image databases by spatial relationship can be effectively performed through visual interface systems. In these systems, the representation of image with 2D strings, which are derived from symbolic projections, provides an efficient and natural way to construct image index and is also an ideal representation for the visual query. With this approach, retrieval is reduced to matching two symbolic strings. However, using 2D-string representations, spatial relationships between the objects in the image might not be exactly specified. Ambiguities arise for the retrieval of images of 3D scenes. In order to remove ambiguous description of object spatial relationships, in this paper, images are referred by considering spatial relationships using the spatial location algebra for the 3D image scene. Also, we remove the repetitive spatial relationships using the several reduction rules. A reduction mechanism using these rules can be used in query processing systems that retrieve images by content. This could give better precision and flexibility in image retrieval.

• Journal of KIISE:Computing Practices and Letters
• /
• v.7 no.3
• /
• pp.260-272
• /
• 2001

In this paper, we have designed a region-based image retrieval system, FRIP(Finding Region In the Pictures). This system includes a robust image segmentation scheme using color and texture direction and retrieval scheme based on features of each region. For image segmentation, by using a circular filter, we can protect the boundary of round object and merge stripes or spots of objects into body region. It also combines scaled and shifted color coordinate and texture direction. After image segmentation, in order to improve the storage management effectively and reduce the computation time, we extract compact features from each region and store as index. For user interface, by the user specified constraints such as color-care / don't care. scale-care / dont care, shape-care / dont care and location-care / dont care, the overal/ matching score is estimated and the top Ie nearest images are reported in the ascending order of the final score.