• Title, Summary, Keyword: Rejuvenation

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Availability Analysis of Systems with Time-Based Software Rejuvenation (시간 기반 소프트웨어 재활 방식의 가용도 분석)

  • Lee, Yutae;Kim, Hyoungseok
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.2
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    • pp.201-206
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    • 2019
  • Rejuvenating a system periodically during the most idle time of the system reduces unexpected downtime caused by software aging and increases its availability. In general, software rejuvenation can be largely divided into two broad categories: time-based rejuvenation policy and condition-based rejuvenation policy. In time-based rejuvenation policy the software rejuvenation is triggered at scheduled time epochs with fixed time intervals, while in condition-based rejuvenation policy the software rejuvenation is performed when system state is checked to satisfy a specific condition. Conditionbased policy adds extra cost to the system due to system monitoring and aging estimation. This paper presents a stochastic model for analyzing time-based software rejuvenation mechanism, where the rejuvenation is triggered at scheduled time epochs with fixed time intervals, and provides an analytical solution for the steady-state availability, the user-perceived availability, and the corresponding cost.

Ad hoc Software Rejuvenation for Survivability

  • Khin Mi Mi Aung;Park, Jong-Sou
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • pp.141-145
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    • 2003
  • We propose the model of Software Rejuvenation methodology, which is applicable for survivability. Software rejuvenation is a proactive fault management technique and being used in fault tolerant systems as a cost effective technique for dealing with software faults. Survivability focuses on delivery of essential services and preservation of essential assets, even systems are penetrated and compromised. Thus, our objective is to detect the intrusions in a real time and survive in face of such attacks. As we deterrent against an attack in a system level, the Intrusion tolerance could be maximized at the target environment. We address the optimal time to execute ad hoc software rejuvenation and we compute it by using the semi Markov process. This is one way that could be really frustrated and deterred the attacks, as the attacker can't make their progress. This Software Rejuvenation method can be very effective under the assumption of unknown attacks. In this paper, we compute the optimum time to perform an ad hoc Software Rejuvenation through intrusions.

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Availability Analysis of Multiplex Systems using Software Rejuvenation Method (소프트웨어 재활 기법을 적용한 다중계 시스템의 가용도 분석)

  • Park, Kie-Jin;Kim, Sung-Soo;Kim, Jai-Hoon
    • Journal of KIISE:Computer Systems and Theory
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    • v.27 no.8
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    • pp.730-740
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    • 2000
  • The software rejuvenation method for highly available multiplex systems uses a pro-active fault-tolerant approach to handle system failures. The software rejuvenation prevents failures from occurring, while the previous methods recover from failures after happening. Especially, since the software aging proceeds fast in the software used for the multimedia mobile computing due to the loss of communications or data, the preventive method from failures using software rejuvenation can be used for the multimedia mobile computing. In this paper, according to the operational parameters such as rejuvenation period, rejuvenation time, failure rate and repair rate of the servers, number of running servers, duration of running time, and type of running modes, we calculate steady-state probabilities, downtime, availability, and cost of the multiplex systems using software rejuvenation method. We validate the closed-form solutions of the mathematical model by experiments based on various operational parameters and find that the software rejuvenation method can be adopted as preventive fault-tolerant technique. The failure rate and unstable rate of the servers are essential factors for the decision making of the rejuvenation policies.

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The Suggestion for Clinical Trial of Face Rejuvenation using Korean Medicine's Embedded Needle (Maesun) Based on Literature Review (매선을 활용한 한의 안면 성형 임상 연구 설계 제안 -한의 안면 성형 임상연구 동향 분석을 바탕으로-)

  • Lee, Jae-Chul;Lim, Chang-Gyu;Kim, Jung-Won;Park, Sun-Hee;Yoon, Jeong-Ho
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.26 no.2
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    • pp.78-87
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    • 2013
  • Objectives : This work aimed to review clinical trial trend of Korean medicine's face rejuvenation and suggest future trial using embedded needle(Maesun) based on Evidence-based medicine's PICO Model. Methods : 46 papers were searched from Oasis and DBPia, then 8 papers were engaged in review of clinical trial trend. Based on PICO model, clinical trial's patient, intervention, and outcome measurement were suggested. Results : Evidence level of clinical trials is relatively low, because their study designs are almost case report or case series. No study have comparison groups. Outcome measurement is varied, however, 3D face scanner were used to measure before-after changes of face. Based on review, we suggested that necessity of intervention standardization, measuring of normal control group and 2D/3D combined outcome measurement of face. Conclusions : There are many demands for revealing efficacy and safety of Korean medicine's intervention, also for face rejuvenation using embedded needle. For meeting the level of demands, more rigorous works are needed.

Analysis of Redundant System with Rejuvenation for High Availability of Networking Service (네트워크 서비스의 가용도 향상를 위한 재활기법의 다중화 시스템 분석)

  • Ryu, Hong-Rim;Shim, Jaechan;Ryu, Hoyong;Lee, Yutae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.9
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    • pp.1717-1722
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    • 2016
  • Availability, one of the important metrics used to assess the performance of network system, is defined as the probability that a system is operational at a given point in time under a given set of environmental conditions. To improve the availability of the network service, the redundancy models and the rejuvenation schemes are the effective schemes to be typically used. In this paper, we analyse the effect of 2N redundancy model and/or rejuvenation scheme on the availability of network service. The 2N redundancy model consists of one active and one standby component and the performance of time-based rejuvenation scheme mainly depends on its rejuvenation period. We design stochastic reward net model for the 2N redundancy model with time-based rejuvenation scheme and analyse the service availability of the model using stochastic Petri net package. We provide some numerical examples of the service availability, which shows that the system with rejuvenation has higher availability than the system without rejuvenation.

Preliminary Standard Procedure for Face Lift and Correction of Nasolabial Fold using Thread-Embedding (Maeseon) of Korean Medicine (안면거상 및 팔자주름 개선을 위한 매선 시술 표준안 제안)

  • LeeL, Jae-Chul;Park, Sun-Hee;Yoon, Jeong-Ho;Kim, Jung-Won;Lim, Chang-Gyu
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.26 no.4
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    • pp.43-50
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    • 2013
  • Objectives : This study aims to suggest preliminary standard procedure for face lift and correction of nasolabial folds using thread-embedding (Maeseon) of Korean medicine(KM). Methods : Three KM practitioners of facial correction and rejuvenation who have over hundred case of practice participated in establishment of standard procedure. Standard procedure contains preprocessing, main procedure for correction, and solution of side effects. Results : Standard procedure is comprised of twelve processes with preprocessing and postprocessing. Preprocessing has position, disinfection, and anesthesia. Main process consists of overall structure correction, face lifting, nasolabial folds correction, and mesh making on cheek. Postprocess covers disinfection, edema prevention. Conclusions : To our knowledge, this is the first work to suggest standard procedure of facial rejuvenation using Maeseon. It would contribute to standardized practice in clinical fields and future study of revealing Maeseon's effectiveness.

Clinical Study on Facial Skin Furrow Measurement Changes after Miso Facial Rejuvenation Acupuncture (미소안면침 시술 후 안면 주름 측정값 변화에 대한 임상적 고찰)

  • Kwon, Na-Hyoun;Kim, Chan-Young;Shin, Ye-Ji;Seo, San;Song, Jeong-Hwa;Baek, Yong-Hyeon;Woo, Hyun-Su;Park, Dong-Suk
    • Journal of Acupuncture Research
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    • v.26 no.6
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    • pp.133-140
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    • 2009
  • Objectives : Miso facial rejuvenation acupuncture is a Korean medical treatment technique for face lifting. The authors aimed to evaluate the effects of Miso facial rejuvenation acupuncture on facial skin furrows. Methods : 11 patients who made first visits to Hyo-Jun Korean Medical Clinic from October 1, 2009 to October 25, 2009 were each given one-time treatment of Miso facial rejuvenation acupuncture treatment. A portable fluorescent dermal diagnostic equipment, ECOSKIN, was used to measure extraocular skin furrows and perioral skin furrows width and depth before and after treatment. Results : Mean width and depth of both the extraocular and perioral skin furrows decreased after one-time Miso facial rejuvenation acupuncture treatment. Extraocular skin furrow width, depth, and perioral skin furrow width showed statistically significant decreases(p=0.003, 0.017, 0.041 respectively). Conclusions : Mean depth and width of both the extraocular and perioral skin furrows decreased after receiving Miso facial rejuvenation acupuncture treatment. Miso facial rejuvenation acupuncture may be an effective treatment for improving wrinkles in clinic.

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The Changes of Facial Temperature by Miso Facial Rejuvenation Acupuncture : A case study (미소안면침 시술 후 안면부 체온변화에 대한 임상적 고찰 : A case study)

  • Hwang, Deok-Sang;Song, Jeong-Hwa;Kim, Yong-Suk;Lee, Kyung-Sub
    • Journal of Oriental Medical Thermology
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    • v.6 no.1
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    • pp.32-38
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    • 2008
  • Objective: To investigate the changes of facial temperature by Miso Facial Rejuvenation Acupuncture treatment. Methods: One middle-aged women who has no other disease was recruited. The Miso Facial Rejuvenation Acupuncture was performed on only right face. We measured the facial temperature using the Digital Infrared Thermal Imaging (DOREX Inc. Spectrum 9000 MB, USA, D.I.T.I.) before, immediate after and 10 minutes after treatment. And we used the Wilcoxon signed rank test (P<0.05) to compare the difference of facial temperature at each time. Results: Right facial temperature (the area treated by acpuncuture) increased immediately from $30.02{\pm}1.87^{\circ}C$ to $32.24{\pm}1.03^{\circ}C$, the change of temperature is statistically significant. At 10 minutes after treatment, right facial temperature decreased little, but there was no statistical significance. Left facial temperature increased little, but there was no statistical significance. The difference between right and left face increased after Miso facial rejuvenation acupuncture treatment. Conclusion: Miso facial rejuvenation acupuncture could make the facial temperature increase.

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Case Study of Facial Palsy Sequela include spasm treated with Miso Facial Rejuvenation Acupuncture (미소안면침을 이용한 안면마비 후 안면경련 환자 임상치험례 보고)

  • Lee, Yu-Jin;Choi, Joo-Ho;Lee, Jong-Cheol;Park, Su-Yeon;Kim, Jong-Han;Choi, Jeong-Hwa;Chun, Hea-Sun;Yoon, In-Ae
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.24 no.3
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    • pp.119-128
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    • 2011
  • Object : The purpose of this study is to evaluate the effect of Miso Facial Rejuvenation Acupuncture on Facial Palsy Sequela. Miso Facial Rejuvenation Acupuncture is an Korean medical treatment technique used for face lifting and facial disease. Method : We tereated a male patients who has Facial palsy sequela include contraction, spasm, synkinesis with Miso Facial Rejuvenation Acupuncture. The treatment was performed one times a week for thirteen times. The effects of the treatment were evaluated VAS(visual analogue scale). Result : After the treatment the grade of VAS was decreased and clinical symptoms were gradually disappaered. Conclusion : Miso Facial Rejuvenation Acupuncture showed improvement in sequela of facial palsy.

Switchover Time Analysis of Primary-Backup Server Systems Based on Software Rejuvenation (소프트웨어 재활기법에 기반한 주-여분 서버 시스템의 작업전이 시간 분석)

  • Lee, Jae-Sung;Park, Kie-Jin;Kim, Sung-Soo
    • The KIPS Transactions:PartA
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    • v.8A no.2
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    • pp.81-90
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    • 2001
  • As the rapid growth of Internet, computer systems are growing in its size and complexity. To meet high availability requirements for the systems, one usually uses both hardware and software fault tolerance techniques. To prevent failures of computer systems from software-aging phenomenon that come from long mission time, we adopt software rejuvenation method that stops and restarts the software in the servers intentionally. The method makes the systems clean and healthy state in which the probability of fault occurrence is very low. In this paper, we study how switchover time affects software rejuvenation of primary-backup server systems. Through experiments, we find that switchover time is an essential factor for deciding the rejuvenation policy.

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