• Database Research
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• v.34 no.3
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• pp.58-68
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• 2018

Distributed computing helps to efficiently store and process large data on a cluster of multiple machines. The performance of distributed computing is greatly influenced depending on the state of the servers constituting the distributed system. In this paper, we propose a self-diagnosis system that collects log data in a distributed system, detects anomalies and visualizes the results in real time. First, we divide the self-diagnosis process into five stages: collecting, delivering, analyzing, storing, and visualizing stages. Next, we design a real-time self-diagnosis system that meets the goals of real-time, scalability, and high availability. The proposed system is based on Apache Flume, Apache Kafka, and Apache Storm, which are representative real-time distributed techniques. In addition, we use simple but effective moving average and 3-sigma based anomaly detection technique to minimize the delay of log data processing during the self-diagnosis process. Through the results of this paper, we can construct a distributed real-time self-diagnosis solution that can diagnose server status in real time in a complicated distributed system.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.9
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• pp.801-806
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• 2001

According as many people use a computer newly, damage of computer virus and hacking is rapidly increasing by the crucial users A computer virus is one of program in computer and has abilities of self reproduction ad destruction like a virus of biology. And hacking is to rob a person's data in a intruded computer and to delete data in a person s computer from the outside. To block hacking that is intrusion of a person s computer and the computer virus that destroys data, a study for intrusion-detection of system and virus detection using a biological immune system is in progress. In this paper, we make a model of positive selection and negative selection of self-recognition process that is ability of T-cytotoxic cell that plays an important part in biological immune system. So we embody a self-nonself distinction algorithm in computer, which is an important part when we detect an infected data by computer virus and a modified data by intrusion from the outside. The composed self-recognition process distinguishes self-file from the changed files. To prove the efficacy of self-recognition algorithm, we use simulation by a cell change and a string change of self file.

• Journal of Information Processing Systems
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• v.5 no.2
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• pp.69-76
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• 2009

Self healing systems are considered as cognation-enabled sub form of fault tolerance system. But our experiments that we report in this paper show that self healing systems can be used for performance optimization, configuration management, access control management and bunch of other functions. The exponential complexity that results from interaction between autonomic systems and users (software and human users) has hindered the deployment and user of intelligent systems for a while now. We show that if that exceptional complexity is converted into self-growing knowledge (policies in our case), can make up for initial development cost of building an intelligent system. In this paper, we report the application of AHSEN (Autonomic Healing-based Self management Engine) to in OKKAM Project infrastructure backbone cluster that mimics the web service based architecture of u-Zone gateway infrastructure. The 'blind' load division on per-request bases is not optimal for distributed and performance hungry infrastructure such as OKKAM. The approach adopted assesses the active threads on the virtual machine and does resource estimates for active processes. The availability of a certain server is represented through worker modules at load server. Our simulation results on the OKKAM infrastructure show that the self healing significantly improves the performance and clearly demarcates the logical ambiguities in contemporary designs of self healing infrastructures proposed for large scale computing infrastructures.

• Journal of Advanced Navigation Technology
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• v.20 no.2
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• pp.107-115
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• 2016

The passenger who use airport spend a lot of time in check-in. They are also delayed in their readiness for departure. Therefore, for decrease in time that is waiting time for handling luggage, recently many airports are expanding self-service. Also internal development and manufacturing for production automation system and IT technology are world-class. So, for localization of self bag drop (SBD) system, I think that application this system in domestic technique and constructing competitive in customer reception system will be efficient airport management. To this end, for looking for optimal conditions when passengers use SBD, this thesis include development simulation of relevance to system. Also this thesis secures information for passenger's in foreign country airport and simulate this data. Finally, that analysis the best management passenger system when the passenger use SDB.

• Journal of Information Technology Services
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• v.9 no.2
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• pp.129-149
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• 2010

Although many organizations have implemented and used ERP systems for years, industry reports point out that the usage level does not reach their expectation. As a result, they do not enjoy the benefits from the investment into ERP systems. This study attempts to develop a research model and test the model empirically for identifying factors that affect the usage of an ERP system at a public organization. This study has classified potential factors into three groups of technical system characteristics (usability, usefulness), organizational support characteristics (operational support, education and training, evaluation and measurement), and user characteristics (organizational citizenship, self-efficacy). Then, a structural equation model has been established on the basis of previous literature and tested with empirical data. In summary, this study has found that self-efficacy, usefulness, and operational support have an effect on the ERP usage. Self-efficacy is the strongest factor; Usefulness is the second; and the third is operational support. On the contrary to the previous literature, this study has not found a significant effect of organizational citizenship on the usage. The result confirms that an organization can increase the ERP usage by improving the usefulness of an ERP system to some extent. However, to boost the usage further, the result implies that organizations need to strengthen the self-efficacy of their members by reinforcing operational support, providing education and training steadily, and establishing an evaluation mechanism in relation with the ERP usage.

• Restorative Dentistry and Endodontics
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• v.27 no.4
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• pp.363-369
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• 2002

최근에 많이 사용되어지고 있는 치과용 접착제는 산 부식 후 수분이 있는 상태에서 적용하는 wet-bonding 술식을 많이 추천하고 있다. 하지만 self-etching primer의 경우 산부식과 priming 과정이 동시에 시행되고, 제조자들은 건조된 치아표면에 적용할 것을 추천하고 있다. 그러나 건조된 정도에 대하여서는 별다른 추천사항이 없으며. 수분이 self-etching primer에 어떤 영향을 미치는지에 대하여서는 별다른 연구가 이루어져 있지 않은 상태이다. 이에 본 연구에서는 치질 삭제 후 남아있는 수분이 self-etching primer의 레진 접착 강도에 어떤 영향을 미치는 지를 알아보고자 하였다. 발거한 대구치 96개를 이용하여 물기가 있는 상태에서 #600 사포로 표면을 연마하고, 법랑질 면을 노출시킨 군과 상아질을 노출시킨 군으로 분류 후, 30분 공기 중 방치 군 (1군), 5초 공기 건조 군 (2군), 1초 공기 건조 군 (3군), 솜으로 약간의 물기를 제거한 군(blot dry) (4군) 등 총 8개의 군으로 나누었다. Self-etching adhesive system인 Clearfil SE Bond primer를 20초간 적용하고, bonding제 도포 후 10초간 광중합 시행하였다. 접착제 처리한 치아면에 몰드를 고정한 후 Clearfil AP-X 복합레진을 2mm 충전하고, 40초간 광중합을 시행하였다. 24시간 후 전단 응력 결합강도를 측정하였으며, 그 결과는 다음과 같이 나타났다. 법랑질과 상아질 모두에서, 30분 건조군과 5초 공기건조군이 1초와 blot drying 군보다 높은 결합강도를 보였으며 통계학적으로 유의한 차이를 보였다(p＜0.05). 본 실험 결과에 의하면 self-etching adhesive system을 사용함에 있어서 법랑질과 상아질군 공히 건조된 상태에서 사용하여야 하며 수분의 존재시 치아와의 결합력이 감소하는 것으로 나타났다. 따라서 임상에서 접착제의 적용시 수분의 조절에 주의하여야 할 것으로 사료된다.

• Journal of Fashion Business
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• v.25 no.5
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• pp.25-37
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• 2021

As the online shopping market grows, channels in the mobile shopping environment have become increasingly diverse as a wide variety of products are introduced every day. This study investigated the effects of the self-construal type, mobile product recommendation system type, and fashion product type on purchase intention. The experimental design of this study was a 2 (self-construal type: independent vs. interdependent) × 2 (product recommendation system: bestseller vs. content-based) × 2 (fashion product type: utilitarian vs. hedonic) 3-way mixed ANOVA. Women (n = 387) in their 20 to 30s residing in Seoul and the Gyeonggi area participated in the study. The data were analyzed with the SPSS 24 program and 3-way ANOVA and simple main effects analyses were conducted. The results were as follows. First, self-construal, product recommendation, and fashion product types had a statistically significant impact on purchase intention. Second, fashion product and consumers' self-construal types had significant interaction effects on purchase intention. Finally, product recommendation and fashion product and self-construal types showed significant 3-way interaction effects on purchase intention. The study confirmed an interaction between the self-construal, type of product recommendation system, and the type of fashion product used in influencing purchase intention.

• Journal of Biosystems Engineering
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• v.21 no.4
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• pp.406-413
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• 1996

A control system for a self-propelled boom sprayer to spray at uniform application rate was developed and evaluated. The ground speed of the sprayer was converted into voltage. The voltage was used as an input signal. Output signal was current of a servo motor, that controlled application pressure of the sprayer with a feedback control system. Spraying was executed at the pressure of 20~55 psi and the speed of 0.640~0.696 km/hr and 1.040-1.131 km/hr. Although the pressure and the speed of sprayer were changed continuously, application rate was tried to keep a nearly constant amount of 666.67 L/ha. This result showed that the developed control system for uniform application rate was adoptable for the self-propelled sprayer.

• Textile Coloration and Finishing
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• v.20 no.5
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• pp.23-27
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• 2008

In this work, poly(diallyldimethylammoniumchloride) (PDDAC) and meso-tetrakis(4-carboxyphenyl)porphyrin were considered to produce the self-assembly fabrication films. This method is based on the layer-by-layer (LbL) deposition produced by the electrostatic attraction between positively charged PDDAC and negatively charged porphyrin ions. The result of multilayer fabrication was discussed with the level of color strength (K/S). K/S spectra of the fabricated multilayer films showed gradual increase behaviors. In addition, the color photo images of the fabricated multilayer films showed that PDDAC and porphyrin were successfully attracted by electrostatic self-assembly forces.

• The Journal of the Korea Contents Association
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• v.2 no.2
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• pp.1-9
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• 2002

In this paper, I design a web based system for self directed leaning. I search a teaching and teaming model for self directed teaming on web. I design a pertinent mood of system to carry out a teaching and teaming model. Also, I propose a Dan which a model d system use pertinently. If a web based system for self directed teaming is used on vacation, after school or actual learning, I expect that we take the effect of instruction.