• Progress in Superconductivity
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• v.9 no.1
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• pp.119-125
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• 2007

We investigated recovery in $Au/YBa_2Cu_3O_7$ (YBCO) thin film meander lines on sapphire substrates. The meander lines were fabricated by patterning YBCO films coated with gold layers. The lines were subjected to simulated AC fault current and then small current was applied for recovery measurements. The samples were immersed in liquid nitrogen during the experiment. After the fault, the resistance decreased linearly, first slowly and then fast to zero. The initial slow decrease was due to the decrease of the meander line temperature, whereas the fast decrease was originated from the transition from the normal state to the superconducting state. The recovery speed depended on the size of samples, and was faster in the smaller samples during the whole period of recovery. The experimental results were analyzed quantitatively with the concept of heat transfer within the sample and to the surrounding liquid nitrogen. A heat balance equation was solved for the initial phase of recovery, and an expression for the time dependence of resistance was obtained. The result agreed with data well.

• Journal of Communications and Networks
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• v.6 no.3
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• pp.235-244
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• 2004

There have been a lot of approaches to evaluate and predict transmission control protocol (TCP) performance in a numerical way. Especially, under the recent advance in wireless transmission technology, the issue of TCP performance over wireless links has come to surface. It is because TCP responds to all packet losses by invoking congestion control and avoidance algorithms, resulting in degraded end-to-end performance in wireless and lossy systems. By several previous works, although it has been already proved that overall TCP performance is largely dependent on its loss recovery performance, there have been few works to try to analyze TCP loss recovery performance with thoroughness. In this paper, therefore, we focus on analyzing TCP's loss recovery performance and have developed a simple model that facilitates to capture the TCP sender's behaviors during loss recovery period. Based on the developed model, we can derive the conditions that packet losses may be recovered without retransmission timeout (RTO). Especially, we have found that TCP Reno can retransmit three packet losses by fast retransmits in a specific situation. In addition, we have proved that successive three packet losses and more than four packet losses in a window always invoke RTO easily, which is not considered or approximated in the previous works. Through probabilistic works with the conditions derived, the loss recovery performance of TCP Reno can be quantified in terms of the number of packet losses in a window.

• Journal of Veterinary Clinics
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• v.22 no.3
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• pp.259-263
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• 2005

To compare cardiopulmonary effects and recovery between total intravenous anesthesia (TIVA) with propofol (PRO group, n=5) and volatile induction/maintenance anesthesia (VIMA) with isoflurane (ISO group, n=5), we investigated changes of heart rate, $SpO_2$, arterial pressure, rectal temperature and respiratory rate during 60 minute anesthesia and 40 minute recovery period in beagle dogs, and investigated recovery (extubation, head lift, sternal position and righting) after 60 minute anesthesia. Rectal temperature was significantly low in ISO group (p<0.05) from 10 to 100 minute. Heart rate was significantly low in ISO group (p<0.05) at 40, 50, 60 minute. Respiratory rate was significantly low in PRO group (p<0.05) at induction and 70 minute. $SpO_2$ tendency was similar. Systolic arterial pressure (SAP) was significantly low in ISO group (p<0.05) at induction and during anesthesia. Recovery was similar in two groups. We concluded that TIVA with propofol is useful in stabilizing rectal temperature and arterial pressure during anesthesia and provide fast and stable recovery.

• Knowledge Management Research
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• v.16 no.1
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• pp.71-93
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• 2015

With the rapid growth of the internet, electronic commerce has become accepted as one of the major purchasing channels for consumers. As more and more consumers search for and purchase products through the internet, intra-industry competition of electronic commerce has become fierce. Therefore, electronic commerce service providers pay attention to factors that prevent existing customers from leaving there services in the service failure situation. In this regard, electronic commerce service providers should make service recovery efforts for consumer recovery satisfaction after service failure. In this study, we suggest that procedural justice, interactional justice, distributive justice and authenticity have positive impacts on recovery satisfaction. In addition, we also propose that involvement plays moderating roles in the relationships between procedural justice, interactional justice, distributive justice, authenticity and recovery satisfaction. We collected empirical data for this study over a period of two weeks from subjects who had service failure recovery experiences through electronic commerce. A total of 224 complete and valid responses were obtained. We carried out data analysis using a two-step methodology with SPSS 20.0 and SmartPLS 2.0. The first step in the data analysis was to establish the internal consistency, convergent validity, discriminant validity of the constructs. In the second step, we examined the structural model. The empirical results support the proposed model and partly identify the moderating effect of involvement differences. The moderate effect results show that procedural justice, distributive justice and authenticity have different impacts on recovery satisfaction in two groups. Cognitive factor such as the procedural justice and distributive justice have stronger impacts on recovery satisfaction in the high-involvement goods than in the low-involvement goods, while emotional factor such as authenticity has a stronger impact on recovery satisfaction in the low-involvement goods than in the high-involvement goods. We expect that this result will provide researchers and managers who are interested in electronic commerce service failure recovery with useful theoretical and practical implications.

• Biomedical Science Letters
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• v.10 no.2
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• pp.121-128
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• 2004

Mast cells and goblet cells have the ability to protect against parasites by increasing mucus production that traps and excludes worms and prevents their intimate contact with the gut mucosa in the host. In this study, we investigated the function of mast cells and goblet cells for the rejection of Echinostoma hortense (E. hortense). In addition, we used both C3H/HeN and BALB/c mice in order to examine whether mast cells and goblet cells function differentially according to the strains of mice. After an oral infection with 30 E. hortense metacercariae, the number of mucosal mast cells and goblet cells, as well as worm recovery rate, were observed in experimentally infected mice between 1 week and 8 weeks post-infection (PI). Worm recovery rates in C3H/HeN and BALB/c mice were 65.7％ and 23％, respectively, in week 1 P.I., indicating that worm expulsion in C3H/HeN mice was higher than in BALB/c mice. Our results demonstrate that the period (week 3 P.I.) in which worm recovery falls rapidly is the same period that the number of goblet cells and mast cells reaches a peak. These results indicate that worm recovery significantly correlates with the growth rate of goblet cells and mast cells (P=0.0482). However, worm expulsion is not associated with goblet cells or mast cells in BALB/c mice.

• Journal of Biosystems Engineering
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• v.3 no.2
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• pp.88-99
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• 1978

In this study, rice harvesting systems suitable to Korean situations and the optimum timing of these systems were determined, respectively, based on experimentally determined factors such as filed yield and the milling quantity and quality measured at various levels of the grain moisture content at harvest. Rice varieties used for the experiment were the AKIBARE (Japonica-type) and the SUWEON 251 (high yielding TONGIL sister-line variety), The harvesting systems studied by the experimental work of this study were traditional system with both the wet material and dry-material threshing system by use of binder with both the dry-material and wet-material threshings, and system by use of combine. Grain samples were taken from final products of the paddy rice harvested from the experiment a fields for each system to measure the recovery rates of the milled rice. The results may be summarized as follows; 1. The milling recovery rate of the AKIBARE variety had highest value within the range of the grain moisture at harvest, showing from 21 to 26 percent. The head-rice recovery for the same variety was a little greater in the wet-material threshing than in the dry-material threshing , higher values of which , were 20 to 25 percent , seen within the range of grain moisture at harvest regardless of the harvesting systems tested. 2. The milling recovery of the SUWEON 251 , when tested for different harvesting systems and harvesting grain moisture, did not show a statistically significant different. In contrast , head-rice recovery for the systems operated by the wet-material threshing was much greater than that by the -material threshing. The difference of the recoveries between these systems range from 2.6 to 4.7 percent. 3. An assessment of the optimum period of -harvest timing for each of the harve\ulcornersting systems tested were made bJ.sed on (a) the maximum total milled-rise yield and (b) the percentage reduction in the total milled-rice yield due to untimely harvest operations. The optimum period determined are: 23-19% for the ATD, AC, STD, SBW, STW systems, 25-21% for the ATW ani ABW systems, and 27-18% for the ABD, SBD, and SC systems, respectively.

• Journal of Digital Contents Society
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• v.12 no.1
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• pp.133-139
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• 2011

Structured P2P (peer-to-peer) networks have received much attention in research communities and the industry. The data stored in structured P2P networks can be located in a log-scale time without using central severs. The link-structure of structured P2P networks should be maintained for keeping log-scale search performance of it. When nodes join or leave structured P2P networks frequently, some links become unavailable and search performance is degraded by these links. To sustain search performance of structured P2P networks, periodic link recovery scheme is generally used. However, when the link recovery period is short or long compared with node join and leave rates, it is possible that sufficient number of links are not restored or excessive messages are used after the link-structure is restored. We propose the adaptive link recovery determination algorithm to maintain the link-structure of structured P2P networks when the rates of node joining and leaving are changed dynamically. The simulation results show that the proposed algorithm can maintain similar QoS under various node leaving rates.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.7
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• pp.545-551
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• 2013

Timing recovery loop composed of the Timing Error Detector(TED), loop filter and resampler is widely used for the timing synchronization in MQASK receivers. Since TED is sensitive to the delay between the symbol period of the signal and sampling period, the output is averaged out when the symbol rate and sampling rate are quite different the recovery loop cannot work at all. This paper presents a sampling frequency discriminator (SRD), which detects the frequency offset of the sampling clock to the symbol clock of the MQASK data transmitted. Employing the SRD, the closed loop timing recovery scheme performs the frequency-aided timing acquisition and achieve the synchronization at extremely high sampling frequency offset, which can be used in variable symbol rate MQASK receivers.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.6 no.1
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• pp.51-63
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• 1999

This study examined two differences in physical and psychological recovery patterns after surgery in the elderly. The sample consisted of 40 patients with abdominal surgery In five large hospitals in Seoul. The data for this study were collected from Apr. 20 to Nov. 26 by structured questionnaire, chart review and call. Physical recovery was assessed by ADL, a Cantril Ladder Scale and a Visual Analogue Scale. Psychological recovery was measured by the Geriatric depression Scale and a Cantril Ladder Scale. The data were analyzed using frequency, percentage, Pearson Correlation Coefficient, and MANOVA by SPSS/WIN. The result are as follows : 1. Physical recovery indicated significant improvement over time with the exception of ADL(F=.812 p=.449). Perceived physical health were significantly improved(F=6.189 p=.004). Pain & discomfort was significantly decreased(F=3.927 p=.025). 2. Perceived psychological health was significantly improved over time(F=20.648 p=.000), but depression showed no statistical significance improvement over time(F=1.393 p=.256). 3. There were no significant effects of sex, age, complication and combined chronic diseases on physical and psychological recovery patterns. 4. There were significant correlations between operation time and pain(r=-.331 p=.020), recovery time and perceived psychological health(r=-.320 p=.024), recovery time and pain(r=.404 p=.005). There were significant correlations between admision period and ADL(r=-.418 p=.004), perceived physical health(r=-.354 p=.014), depression(r=.280 p=.042), and perceived psychological health(r=-.447 p=.002). BRAS showed significant correlation with ADL(r=-.458 p=.002). 5. With an increase in the degree of perceived health(physical and psychological), ADL was significantly increased. With an increased in the degree of depression and pain, ADL and perceived health(physical and psychological) were significantly decreased. In conclusion, the elderly patient recovered significantly over time with the exception of ADL and depression. It these we suggested to considered when planning care for elderly patients.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.7-10
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• 2002

Concrete used up to date semipermanent architecture material but now day concrete early deterioration emboss social issue because of construction structure and environmental factor. so, many study of deterioration concrete construction improve durability used impregnation alkalization agent. In These to Study of derelop reoairmeat material in reduce carbonation. xoncrete Building use Alkalinity Recovery Agent which is Realkalinity and strength surface. Alkalinity Recovery Agent undisposed application volume and cure the concrete period. To study Alkalinity Recovery Ahent spray and cure the concrete propriery in field.