• Management Science and Financial Engineering
• /
• v.20 no.1
• /
• pp.1-9
• /
• 2014

In multi-objective scheduling problems, the objectives are usually in conflict. To obtain a satisfactory compromise and resolve the issue of NP-hardness, most existing works have suggested employing meta-heuristic methods, such as genetic algorithms. In this research, we propose a novel data-driven approach for generating a single solution that compromises multiple rules pursuing different objectives. The proposed method uses a data mining technique, namely, random forests, in order to extract the logics of several historic schedules and aggregate those. Since it involves learning predictive models, future schedules with the same previous objectives can be easily and quickly obtained by applying new production data into the models. The proposed approach is illustrated with a simulation study, where it appears to successfully produce a new solution showing balanced scheduling performances.

• Journal of Information Technology Applications and Management
• /
• v.12 no.1
• /
• pp.125-140
• /
• 2005

Nowadays, we have many embedded systems which store and process multimedia data. For multimedia systems using hard disks as storage media such as DVR, existing file systems are not the right choice to store multimedia data in terms of cost. performance and reliability. In this study we designed a reliable file system with very high performance for embedded multimedia applications. The proposed file system runs with quite simple disk layout to reduce time to initialize and to recover after power failures, uses a large data block to speed up the sequential accesses, incorporates a time-based indexing scheme to improve the time-based random accesses and boosts reliability by backing up the important meta data on a small NVRAM. We implemented the file system on a Linux-based DVR and verified the performance by comparing with existing file systems.

• KIPS Transactions on Software and Data Engineering
• /
• v.3 no.12
• /
• pp.523-530
• /
• 2014

Ontology alignment is the way to share and reuse of ontology knowledge. Because of the ambiguity of concept, most ontology alignment systems combine a set of various measures and complete enumeration to provide the satisfactory result. However, calculating process becomes more complex and required time increases exponentially since the number of concept increases, more errors can appear at the same time. Lately the focus is on meta-matching using the heuristic algorithm. Existing meta-matching system tune extra parameter and it causes complex calculating, as a consequence, the results in the various data of specific domain are not good performed. In this paper, we propose a high performance algorithm by using DCS that can solve ontology alignment through simple process. It provides an efficient search strategy according to distribution of Levy Flight. In order to evaluate the approach, benchmark data from the OAEI 2012 is employed. Through the comparison of the quality of the alignments which uses DCS with state of the art ontology matching systems.

• Journal of Korea Multimedia Society
• /
• v.11 no.5
• /
• pp.651-660
• /
• 2008

Flash memory is widely used in embedded systems because of its benefits such as non-volatile, shock resistant, and low power consumption. However, NAND flash memory suffers from out-place-update, limited erase cycles, and page based read/write operations. To solve these problems, YAFFS and RFFS, the flash memory file systems, are proposed. However YAFFS takes long time to mount the file system, because all the files are scattered all around flash memory. Thus YAFFS needs to fully scan the flash memory. To provide fast mounting, RFFS has been proposed. It stores all the block information, the addresses of block information and meta data to use them at mounting time. However additional operations for the meta data management are decreasing the performance of the system. This paper presents a new NAND flash file system called ERFFS (Efficient and Reliable Flash File System) which provides fast mounting and recovery with minimum mata data management. Based on the experimental results, ERFFS reduces the flash mount/recovery time and the file system overhead.

• Safety and Health at Work
• /
• v.2 no.1
• /
• pp.70-82
• /
• 2011

Objectives: Ischemic heart disease (IHD) is a major cause of death in Korea and known to result from several occupational factors. This study attempted to estimate the current magnitude of IHD mortality due to occupational factors in Korea. Methods: After selecting occupational risk factors by literature investigation, we calculated attributable fractions (AFs) from relative risks and exposure data for each factor. Relative risks were estimated using meta-analysis based on published research. Exposure data were collected from the 2006 Survey of Korean Working Conditions. Finally, we estimated 2006 occupation-related IHD mortality. Results: For the factors considered, we estimated the following relative risks: noise 1.06, environmental tobacco smoke 1.19 (men) and 1.22 (women), shift work 1.12, and low job control 1.15 (men) and 1.08 (women). Combined AFs of those factors in the IHD were estimated at 9.29% (0.3-18.51%) in men and 5.78% (-7.05-19.15%) in women. Based on these fractions, Korea's 2006 death toll from occupational IHD between the age of 15 and 69 was calculated at 353 in men (total 3,804) and 72 in women (total 1,246). Conclusion: We estimated occupational IHD mortality of Korea with updated data and more relevant evidence. Despite the efforts to obtain reliable estimates, there were many assumptions and limitations that must be overcome. Future research based on more precise design and reliable evidence is required for more accurate estimates.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.05a
• /
• pp.123-125
• /
• 2016

Big data analysis refers the ability to store, manage and analyze collected data from an existing database management tool. In addition, extract value from large amounts of structured or unstructured data set and means the technology to analyze the results. Meta-analysis refers to a statistical literature synthesis method from the quantitative results of many known empirical studies. We conducted a meta-analysis and review of between success factors based the information systems success model researches. This study focused a total of 14 research papers that established causal relationships between success factors based the information systems success model published in Korea academic journals during 2000 and 2016. Based on these findings, several theoretical and practical implications were suggested and discussed with the difference from previous researches.

• Interdisciplinary Bio Central
• /
• v.5 no.1
• /
• pp.1.1-1.8
• /
• 2013

High quality publicly-available transcriptomic data representing relationships in gene expression across a diverse set of biological conditions is used as a context network to explore transcriptomics of the CNS. The context network, 18367Hu-matrix, contains pairwise Pearson correlations for 22,215 human genes across18,637 human tissue samples1. To do this, we compute a network derived from biological samples from CNS cells and tissues, calculate clusters of co-expressed genes from this network, and compare the significance of these to clusters derived from the larger 18367Hu-matrix network. Sorting and visualization uses the publicly available software, MetaOmGraph (http://www.metnetdb.org/MetNet_MetaOm-Graph.htm). This identifies genes that characterize particular disease conditions. Specifically, differences in gene expression within and between two designations of glial cancer, astrocytoma and glioblastoma, are evaluated in the context of the broader network. Such gene groups, which we term outlier-networks, tease out abnormally expressed genes and the samples in which this expression occurs. This approach distinguishes 48 subnetworks of outlier genes associated with astrocytoma and glioblastoma. As a case study, we investigate the relationships among the genes of a small astrocytoma-only subnetwork. This astrocytoma-only subnetwork consists of SVEP1, IGF1, CHRNA3, and SPAG6. All of these genes are highly coexpressed in a single sample of anaplastic astrocytoma tumor (grade III) and a sample of juvenile pilocytic astrocytoma. Three of these genes are also associated with nicotine. This data lead us to formulate a testable hypothesis that this astrocytoma outlier-network provides a link between some gliomas/astrocytomas and nicotine.

• Journal of KIISE:Computing Practices and Letters
• /
• v.8 no.5
• /
• pp.530-539
• /
• 2002

Recently, there have been a lot of researches to develop an archive system for news videos that usually has a fixed structure. However, since the meta-data representation and storing schemes for news video are different from each other in the previously proposed archive systems, it was very hard to exchange these meta-data. This paper proposes a scheme for news video based on MPEG-7 MDS that is an international standard to represent the contents of multimedia, and a summarization mechanism reflecting the characteristics of shots in the news videos. The proposed scheme for news video uses the MPEG-7 MDS schemes such as VideoSegment and TextAnnotation to keep the original structure of news video, and the proposed summarization mechanism uses a slide-show style presentation of key frames with associated audio to reduce the data size of the summary video.

• Journal of KIISE:Computing Practices and Letters
• /
• v.15 no.2
• /
• pp.98-113
• /
• 2009

Conventional file systems for harddisk drive cannot be applied to NAND flash memory, because the physical characteristics of NAND flash memory differs from those of harddisk drive. To address this problem, various file systems with better reliability and efficiency have also been developed recently. However, those file systems have inherent overheads for updating the file's metadata pages, because those file systems save file's meta-data and data separately. Furthermore, those file systems have a critical reliability problem: file systems fail when either a page in meta-data of a file system or a file itself fails. In this paper, we propose a self-description page technique and In Memory Core File System technique to address these efficiency and reliability problems, and develop SDFS(Self-Description File System) newly. SDFS can be safely recovered, although some pages fail, and improves write and read performance by 36% and 15%, respectively, and reduces mounting time by 1/20 compared with YAFFS2.

• Journal of Korean Medicine Rehabilitation
• /
• v.32 no.3
• /
• pp.29-35
• /
• 2022

Objectives The purpose of this systematic review is to analyse randomized controlled trials about acupuncture for patellofemoral pain syndrome (PFPS) and evaluate it's pain improvement effect. Methods Studies will be searched from ten databases (Medline/PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure [CNKI], WanFang Data, Citation Information by NII [CiNII], ScienceON, Koreanstudies Information Service System [KISS], KMBASE, and KoreaMed). Participants will be patients diagnosed with PFPS, regardless of cause, gender, age or race, and interventions will be acupuncture, electroacupuncture, dry needling, fire needle, and acupotomy. Other treatments than interventions will be the control group and the main outcome will be reviewed by visual analogue scale (VAS). Results Data will be extracted and assessed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis flow chart and Cochrane risk of bias tools. Meta-analysis will be conducted using random effect model within 95% confidence interval. Conclusions We expect this systematic review to provide useful data about the pain improvements of patellofemoral pain using acupuncture and expect to stimulate and systematize acupuncture treatment on PFPS in the future.