• Journal of Digital Contents Society
• /
• v.15 no.5
• /
• pp.631-642
• /
• 2014

The main memory DBMS is operated which the contents of the table that resides on a disk at the same time as the drive is in the memory. However, because the main memory DBMS stores the data and transaction log file using the disk file system, there are a limit to the speed at which the CPU accesses the memory. In this paper, I evaluated the performance through analysis of the application side difference the technology that has been implemented in Altibase system of main memory DBMS and Sybase of disk-based DBMS. When the application performance of main memory DBMS is in comparison with the disk-based DBMS, the performance of main memory DBMS was outperformed 1.24~3.36 times in the single soccer game, and was outperformed 1.29~7.9 times in the soccer game / special soccer. The result of sale transaction response time showed a fast response time of 1.78 ~ 6.09 times.

• Journal of Korean Clinical Nursing Research
• /
• v.26 no.2
• /
• pp.131-140
• /
• 2020

Purpose: This study aims to describe the characteristics of safety incidents and factors associated with injury for patients with Home Mechanical Ventilation (HMV) at the hospital. Methods: This is a retrospective study. Data were collected from the work log of respiratory home care nurses and the patients' electronic medical records were investigated. In order to compare group differences, independent t-test and χ² test were used. Associated factors with injury development were identified by generalized mixed modeling analysis controlling for age and gender. Results: A total of 304 patients on HMV were included in this study, among which 129 (42.4%) experienced 352 HMV-related incidents. Mean frequency of incidents for each patient was 5.11±3.98, ranged from 1 to 15 times. In 19.0% of the incidents, injury was developed. Types of incident and persons involved in the incidents were significantly associated with the patient's injury. In the case of the safety incidents, patient's injury was significantly higher in accidents caused by respiratory circuit problems compared to those caused by problems with the ventilator operation by the medical staff (coefficient=1.25, p=.020). In addition, in the case of those involved in the safety incidents, patient's injury was significantly higher in the accident caused by the patient family members or caregivers than that caused by the medical personnel (coefficient=1.25, p=.019). Conclusion: In order to minimize injury caused by incidents in patients with HMV, hospitals need to provide systemic education to their medical staff and caregivers to enhance awareness of the importance of reporting and safety management.

• The Journal of Korean Association of Computer Education
• /
• v.12 no.6
• /
• pp.21-32
• /
• 2009

This paper proposes a method to extract a user's intention automatically and implementation of intention map that support a user can appropriate search results using a user' information need accurately. It selects user intention based on searching history obtained from previous users' same queries and extracts user intentions by using clustering algorithm and user intention extraction algorithm, extracted user intentions are represented in an intention map base on a theory of knowledge representation. For the efficiency analysis of intention map, we extracted user intentions using 2,600 search history data which provided by a current domestic commercial search engine. The experimental results using the information intention map search when using general search engines represent more than satisfaction was statistically significant.

• Journal of Radiation Protection and Research
• /
• v.28 no.1
• /
• pp.59-63
• /
• 2003

Purpose : Measurement of transmission dose is useful for in vivo dosimetry of QA purpose. The objective of this study is to develope an algorithm for estimation of tumor dose using measured transmission dose for open radiation field. Materials and Methods : Transmission dose was measured with various field size (FS), phantom thickness (Tp), and phantom chamber distance (PCD) with a acrylic phantom for 6 MV and 10 MV X-ray Source to chamber distance (SCD) was set to 150 cm. Measurement was conducted with a 0.6 cc Farmer type ion chamber. Using measured data and regression analysis, an algorithm was developed for estimation of expected reading of transmission dose. Accuracy of the algorithm was tested with flat solid phantom with various settings. Results : The algorithm consisted of quadratic function of log(A/P) (where A/P is area-perimeter ratio) and tertiary function of PCD. The algorithm could estimate dose with very high accuracy for open square field, with errors within ${\pm}0.5%$. For elongated radiation field, the errors were limited to ${\pm}1.0%$. Conclusion : The developed algorithm can accurately estimate the transmission dose in open radiation fields with various treatment settings.

• Journal of the Korean Society for information Management
• /
• v.27 no.2
• /
• pp.37-60
• /
• 2010

The purpose of this study is to investigate image search query reformulation patterns in relation to image attribute categories. A total of 592 sessions and 2,445 queries from the Excite Web search engine log data were analyzed by utilizing Batley's visual information types and two facets and seven sub-facets of query reformulation patterns. The results of this study are organized with two folds: query reformulation and categorical transition. As the most dominant categories of queries are specific and general/nameable, this tendency stays over various search stages. From the perspective of reformulation patterns, while the Parallel movement is the most dominant, there are slight differences depending on initial or preceding query categories. In examining categorical transitions, it was found that 60-80% of search queries were reformulated within the same categories of image attributes. These findings may be applied to practice and implementation of image retrieval systems in terms of assisting users' query term selection and effective thesauri development.

• Tunnel and Underground Space
• /
• v.26 no.3
• /
• pp.166-180
• /
• 2016

The present study numerically simulated the CO2 injection into the saline aquifer of CO2CRC Otway pilot project and the resulting hydrological-mechanical coupled process in the storage site by TOUGH-FLAC simulator. A three-dimensional numerical model was generated using the stochastic geological model which was established based on well log and core data. It was estimated that the CO2 injection of 30,000t over a period of 200 days increased the pressure near the injection point by 0.5 MPa at the most. The pressure increased rapidly and tended to approach a certain value at an early stage of the injection. The hydrological and mechanical behavior observed from the CO2 flow, effective stress change and stress-strength ratio revealed that the CO2 injection into the saline aquifer under the given condition would not have significant effects on the mechanical safety of the storage site and the hydrological state around the adjacent fault.

• Journal of the Korean GEO-environmental Society
• /
• v.6 no.1
• /
• pp.53-62
• /
• 2005

This paper estimates the long-term settlement of Kimpo metropolitan landfill based on measured settlement data from 180 landfill monitors accumulated over a period of 12 years. Comparison of domestic and international settlement records indicate that the domestic compression rate is slightly lower due to greater portion of organic component. Several existing settlement models are used to compare with the observed behavior and also to estimate long-term settlement. The hyperbolic, Gibson & Lo, Bjarngard & Edgers and Power Creep Law models compare well with the measured settlement of the Kimpo metropolitan landfill. The settlement models are further used to estimate long-term settlement. Bjarngard & Edgers and Power Creep Law models result in higher estimates of the long-term settlement compared to the hyperbolic and Gibson & Lo models. Further comparisons indicate that other models, including Sowers and log models, are inapproriate for predicting the long-term settlement of the Kimpo metropolitan landfill.

• Korean Journal of Metals and Materials
• /
• v.49 no.4
• /
• pp.275-280
• /
• 2011

This paper focuses on reliability prediction of long-term creep strength for Modified 9Cr-1Mo steel (Gr. 91) which is considered as one of the structural materials of next generation reactor systems. A "Z-parameter" method was introduced to describe the magnitude of standard deviation of creep rupture data to the master curve which can be plotted by log stress vs. The larson-Miller parameter (LMP). Statistical analysis showed that the scattering of the Z-parameter for the Gr. 91 steel well followed normal distribution. Using this normal distribution of the Z-parameter, the various reliability curves for creep strength design, such as stress-time temperature parameter reliability curves (${\sigma}$-TTP-R curves), stress-rupture time-reliability curves (${\sigma}-t_{r}-R$ curves), and allowable stress-temperature- reliability curves ([${\sigma}$]-T-R curves) were reasonably drawn, and their results are discussed.

• Journal of Convergence for Information Technology
• /
• v.10 no.12
• /
• pp.9-14
• /
• 2020

Currently, NTIS (National Technology Information Service) is building an interactive search service based on artificial intelligence technology. In order to understand users' search intentions and provide R&D information, an interactive search service is built based on deep learning models and morpheme analyzers. The deep learning model learns based on the log data loaded when using NTIS and interactive search services and understands the user's search intention. And it provides task information through step-by-step search. Understanding the search intent makes exception handling easier, and step-by-step search makes it easier and faster to obtain the desired information than integrated search. For future research, it is necessary to expand the range of information provided to users.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.33 no.4
• /
• pp.609-619
• /
• 2023

Recently, crimes using drones, one of the IoT industries have been continuously reported. In particular, drones are characterized by easy access and free movement, so they are used for various crimes such as transporting explosives, transporting drugs, and illegal recording. In order to analyze and investigate these criminal acts, drone forensic research is highly emphasized. Media data, PII, and flight records are digital forensic artifacts that can be acquired from drones, in particluar flight records are important artifacts since they can be used to trace drone activities. Therefore, in this paper, the characteristics of the deleted flight record files of DJI drones are presented and verified using the Phantom3, Phantom4 andMini2 models, two drones with differences in characteristics. Additionally, the recovery level is analyzed using the flight record file characteristics, and lastly, drones with the capacity to recover flight records for each drone model and drone models without it are classified.