• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제10권1호
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• pp.83-93
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• 2006

본 논문에서는 유비쿼터스 컴퓨팅 환경에서 규칙 기반의 네트워크 장애 복구 시스템을 제안한다. 이 시스템은 유비쿼터스 컴퓨팅 환경에서 네트워크에 장애가 발생하였을 때, 정해진 규칙을 기반으로 장애를 스스로 복구할 수 있는 장애 관리 시스템이다. 시스템에 적용되는 규칙들을 네트워크 장애의 원인으로 분류하여 제시하였다. 그리고 본 논문에서는 네트워크 장애 복구 시스템이 각 상황에 맞게 규칙이 적용됨을 시뮬레이션을 통해 증명하였다.

• 산업기술연구
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• 제15권
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• pp.51-62
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• 1995

Databases can crash due to various failures in computer systems. Recovery is a mechanism for restoring consistent data from damages caused by the by the failures and is an essential feature in database systems. This paper surveys recovery techniques for memory resident database systems. We first describe the basic architecture for memory resident database systems, and point out the main factors affecting their performance enhancement. Next, we explain the write-ahead logging(WAL), a recovery technique widely-used in most disk resident database systems, for easy understanding of basic recovery mechanisms. And then, we discuss some new concepts employed in memory resident database systems recovery. Finally, we present a representative memory resident database recovery technique, which is based on a special purpose hardware called HALO, as a case study.

• 한국콘텐츠학회논문지
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• 제6권6호
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• pp.56-63
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• 2006

키 복구 연구는 많은 논란에도 불구하고 연구가 확대되고 있는 주제로서, 키 관리의 형태로 법인차원에서 필요하게 되었다. 네트워크에 연결된 시스템들은 TCP/IP의 인터넷 IP 계층에서 키 복구를 도입하여 사용하고 있다. IETF 프로토콜 중 IPSec은 인터넷의 네트워크 계층에서 IP 메시지에 대하여, 암호화 서비스와 인증 서비스를 제공하는 보안 프로토콜이다. 본 논문은 IETF의 인터넷 표준 구조와 호환되게 키 복구 정보를 포함하는 데이터를 전송하는 방법을 제안하고 있다.

• Archives of Plastic Surgery
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• 제43권5호
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• pp.411-417
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• 2016

Background Facial hypoesthesia is one of the most troublesome complaints in the management of facial bone fractures. However, there is a lack of literature on facial sensory recovery after facial trauma. The purpose of this study was to evaluate the facial sensory recovery period for facial bone fractures using Neurometer. Methods Sixty-three patients who underwent open reduction of zygomatic and blowout fractures between December 2013 and July 2015 were included in the study. The facial sensory status of the patients was repeatedly examined preoperatively and postoperatively by Neurometer current perception threshold (CPT) until the results were normalized. Results Among the 63 subjects, 30 patients had normal Neurometer results preoperatively and postoperatively. According to fracture types, 17 patients with blowout fracture had a median recovery period of 0.25 months. Twelve patients with zygomatic fracture had a median recovery period of 1.00 month. Four patients with both fracture types had a median recovery period of 0.625 months. The median recovery period of all 33 patients was 0.25 months. There was no statistically significant difference in the sensory recovery period between types and subgroups of zygomatic and blowout fractures. In addition, there was no statistically significant difference in the sensory recovery period according to Neurometer results and the patients' own subjective reports. Conclusions Neurometer CPT is effective for evaluating and comparing preoperative and postoperative facial sensory status and evaluating the sensory recovery period in facial bone fracture patients.

• 재활간호학회지
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• 제15권2호
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• pp.109-116
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• 2012

Purpose: This study was conducted to investigate influencing factors on recovery among alcoholics. Methods: The participants were 123 hospitalized patients with alcohol use disorder in two hospitals in Gyeonggi province. The data were collected from May 16 to June 4, 2012 using self-report questionnaires including Hanil Alcohol Insight Scale, Alcohol Abstinence Self-Efficacy Scale, and Recovery Scale. The data were analyzed using the SPSS/Win 18.0 program with descriptive statistics, Pearson's correlation coefficient and regression analysis. Results: Recovery is positively related to abstinence self-efficacy and duration of abstinence. Recovery differed by insight type, gender, and occupation. Insight, duration of abstinence, gender, and occupation accounted for 59.1% of the variance in recovery of the alcoholics. Conclusion: The influencing factors on recovery among alcoholics were insight, duration of abstinence, gender, and occupation. Programs focusing on insight, abstinence self-efficacy, and abstinence maintenance should be developed and provided. When developing the programs, the environmental context in which the alcoholics work should be considered.

• 설비공학논문집
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• 제26권2호
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• pp.61-66
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• 2014

Exhaust heat recovery ventilation systems conserve energy through enthalpy recovery between air intake and exhaust, and they are being increasingly used. An exhaust heat recovery ventilation system can be installed in the ceiling of a balcony or emergency evacuation space. However, in the case of fire, the emergency evacuation space has to by law remain as empty space, and therefore, a ventilation system can't be installed in an emergency evacuation space. Therefore, the need for a proper installation space for a ventilation system is emphasized. In this study, to install a heat recovery ventilation system in a lightweight wall, a heat exchanger was assembled of thickness below 140 mm. The efficiency of heat recovery was analyzed through performance experiment, in the case of the cooling and heating mode. The heat recovery efficiency increases when the surface area is increased, by using closer channel spacing in the heat exchanger, or by increasing the size of the heat exchanger.

• 식품보건융합연구
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• 제7권4호
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• pp.23-29
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• 2021

This study analyzes the physiological changes that occur after free diving and studies peroxidants and antioxidants according to the recovery method. Accordingly, the purpose of this study is to provide proper rest methods after free diving and provide basic data for free diving research. Eight male college students recovered for 30 minutes after 20 free injections at a 5-meter diving site, 20 free injections after a week's car wash, and recovered for 30 minutes after collecting blood during recovery to analyze the effects of peroxidants and antioxidants. Comparison of changes in peroxidants and antioxidants in recovery methods after free-diving iterations showed that SOD tended to decrease immediately after free-diving, increasing MDA to 10 minutes after recovery, but no significant difference was found. The purpose of this study is to observe physiological changes according to the recovery method after free diving and to propose an appropriate recovery method after free diving. However, there was no significant difference in all the restoration methods, and 20 freediving was not high kinetic intensity for the subjects, which is believed to have resulted in the following results. Therefore, it was discussed that the repetitive diving strength should be higher to confirm a significant difference in the recovery method after free diving.

• Asia Marketing Journal
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• 제17권2호
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• pp.39-62
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• 2015

Relatively little studies have investigated employee recovery from internal service failure, especially from the employees' perspective. When handling customer complaints, employees must not only deal with legitimate customer demands after a service failure, such as providing an apology, rectifying the problem, and offering compensation, but they must also manage illegitimate dysfunctional customers, who may yell, threaten, and even physically harm the employee. These negative experiences can have strong effects, and employees can exhibit higher levels of stress such as burnout and emotional labor, which have been linked to dissatisfaction, tension and anxiety, reduced performance and effectiveness, and a greater propensity to leave the firm, ultimately leading to negative financial consequences for the firm. These conditions result in internal service failure and create the need to recover employees-in other words, internal service recovery. However, little research has examined this issue so far. The purpose of the current study, therefore, is to investigate the relationship between internal service recovery and employee outcomes. A pre-test, post-test between-subjects experimental design was developed. Participants were 166 part-time students who were working full-time. The average age of the participants was 36.74 years, and 57.50% of them were female. The average length of employment was 13 years. Participants were randomly assigned to one of four groups of approximately equal size. Three of the groups were subjected to an experimental situation involving an internal service failure, while one group was not exposed to failure, thereby acting as a control group. This study contributes to the service marketing literature in several ways. First, the study extends service failure and/or recovery research by examining recovery in an employee context. Second, this study attempts to measure internal service recovery and to empirically demonstrate its relationship to employee outcomes. Third, this investigation emphasizes the managerial importance of internal service recovery. For example, understanding the nature of the relationships between internal service recovery and its consequences can improve the effectiveness and efficiency of managers' resource allocation decisions.

• 한국가축번식학회지
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• 제22권1호
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• pp.89-94
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• 1998

A study was made to investigate the effects of concerning factors with IGF-I recovery on the final IGF-I concentration in the effluent and to establish recovery conditions of IGF-I using liquid emulsion membranes(LEM). D2EHPA was best carrier among Amberlite LA2, Aliquit 336 and D2EHPA for recovery rate of IGF-I. Recovery rate of IGF-I by D2EHPA volume in the oil phase was increased as increasing D2EHPA volume, and optimal volume of D2EHPA was 5% in this experiment. The recovery rate of IGF-I by D2EHPA was increased by the decreasing from pH 7 to pH 4 of external phase. Therefore, optimal pH value was 4.0. Optimal concentrations of sulfuric acid in internal phase, paraffin oil in oil phase and Span 80 for recovery rate of IGF-I were 0.1M, 2.0% and 5%, respectively, and optimal W/O rate was 2. These results suggested that optimal conditions for recovery of IGF-I were D2EHPA(5%) as carrier, pH 4.0, 0.1M sulfuric acid, 2% paraffin oil, 2.0 W/O rate and 5.0% Span 80.

• 한국통신학회논문지
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• 제29권7B호
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• pp.650-659
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• 2004

국내 무선 네트워크 환경은 사용자의 서비스 요구 수용과 시장 성장으로 인해 빠르게 변화하고 있다. 이에 따라 무선 구간에서 TCP(transmission control protocol)를 이용한 신뢰성 있는 데이터 전송도 늘어날 전망이다. TCP는 유선 네트워크에서 사용함을 가정으로 만들어졌기 때문에 무선에서 발생할 수 있는 비 혼잡 손실에 의해 많은 성능 저하를 겪을 수 있다. 특히 RTO(retransmission timeout)은 TCP의 성능에 많은 영향을 미친다. 본 논문에서는 송신단에서 fast recovery과정 중에 발생한 패킷 손실을 빠르게 감지하여 RTO없이 복구함으로써 성능저하를 줄일 수 있는 DAC$^{＋}$(Duplicate Acknowledgement Counting)와 EFR(Extended Fast Recovery)을 제안한다. 제안 알고리듬을 TCP NewReno와 비교했을 때 정상 상태에서 fast recovery 확률이 높고, 이에 따른 RTO 감소로 인해 response time이 줄어드는 것을 확인할 수 있다.