• Archives of Plastic Surgery
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• v.48 no.1
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• pp.26-32
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• 2021

Background Although loss of sensation in patients with breast cancer after mastectomy followed by breast reconstruction is an important factor affecting patients' quality of life, the mechanism of sensory recovery is still unclear. Our study aimed to identify variables that affect sensory recovery, especially pain, in reconstructed breasts. Methods All patients with breast cancer who underwent mastectomy followed by immediate breast reconstruction, including nipple reconstruction or areolar tattooing, were included in this study. Sensation was evaluated in the nipple as an endpoint of sensation recovery of the whole breast. Patients rated pain severity using a 3-point verbal rating scale (VRS): grade 0, no pain; grade 1, mild to moderate pain; and grade 2, severe pain. The VRS was assessed by a single experienced plastic surgeon. Results In the univariate analysis, the odds ratio (OR) for sensation recovery was 0.951 for age (P=0.014), 0.803 for body mass index (P=0.001), 0.996 for breast volume before surgery (P=0.001), 0.998 for specimen weight after mastectomy (P=0.040), and 1.066 for the period between mastectomy and sensory assessment (P=0.003). In the multivariate analysis, the variables that showed a significant effect were age (OR, 0.953; P=0.034), the period between mastectomy and sensory assessment (OR, 1.071; P=0.006), and reconstruction using abdominal tissue instead of prosthetic reconstruction (OR, 0.270; P=0.004). Conclusions Based on our results, it can be inferred that aging has a negative impact on the recovery of sensation, breast sensation improves with time after surgery, and the recovery of sensation is better in prosthetic reconstruction.

• Physical Therapy Korea
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• v.19 no.2
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• pp.48-58
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• 2012

The objective of this study was to evaluate the effects of mirror therapy on motor function recovery following a stroke through a systemic review and meta-analysis. In total, nine of the 48 studies were identified from search engines between 1997 and 2011, as well as from a review of the reference lists of each identified study. The quality of each study was assessed using Jadad scale, and the effect size was calculated as a Cohen's effect size using MetaAnalyst (Beta 3.13). The overall effect size of the mirror therapy was 2.005 (95% confidence interval=1.041~2.970) in a random-effects model. This finding suggests that mirror therapy is beneficial for improving motor function following a stroke. The results from the subgroup analysis according to categorical variables were as follows: First, the effect size was larger for an onset time of less than 1 year (1.166) than for a duration of 1 year or more (.668). Second, the effect size of unpublished dissertations (1.610) was larger than published articles (1.221). Third, motor recovery of upper extremities (1.609) had a greater effect than motor recovery of lower extremities (.903). The major limitation of this study is the relatively small study population. Therefore, further individual studies of mirror therapy should be conducted in order to generalize the effects. In addition, mirror therapy supervised by a physical therapist should be recognized as a potential approach to manage motor function following a stroke and recommended to patients to improve their motor function.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.5
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• pp.381-387
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• 2017

Fiber-reinforced composites not only have a direction of thermal expansion coefficient, but also inevitably suffer thermal stress effects due to the difference between the manufacturing process temperature and the actual use temperature. The damage caused by thermal stress is more prominent in the case of thick composite laminates, which are increasingly applied in the aerospace industry, and have a great influence on the mechanical function and fracture strength of the laminates. In this study, the dimensional reduction and thermal stress recovery theory of composite beam structure having high slenderness ratio is introduced and show the efficiency and accuracy of the thermal stress comparison results between the 3-D finite element model and the dimension reduction beam model. Efficient recovery analysis study will be introduced by reconstructing the thermal stress of the composite beam section applied to the thermal environment by constructing the dimensional reduction modeling and recovery relations.

• Korean Journal of Metals and Materials
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• v.48 no.3
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• pp.203-209
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• 2010

An application of the instrumented indentation technique has been expanded from the measurements of hardness and elastic modulus to the analysis of residual stress. A slope of the indentation loading curve increases (or decreases) according to compressive (or tensile) residual stress. A theoretical equation has been established for quantifying residual stress from the slope change. However, a precise observation of the remnant indents is indispensible because the theoretical approach needs actual contact information. In addition, the conventional hardness test is still used for predicting the residual stress distribution of welded joints. Thus, we observed the three-dimensional morphologies of the remnant indents formed on artificial stress states and analyzed stress effects on morphological recovery of the indents. First, a depth recovery ratio, which has been regarded as a sensitive stress indicator, did not show a clear dependency with the residual stress. Thus an analysis on volumetric recovery was tried in this study and yielded a inverse proportional behavior with the residual stress. In addition, an elastic to plastic volume recovery ratio showed more significant correlation with the residual stress.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.10
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• pp.1339-1344
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• 2010

MSM (Modal Superposition Method) is a technique for analyzing structural durability by taking the vibration characteristics into consideration. In this paper, MSR (Modal Stress Recovery) method, which is similar to MSM, was reviewed to check its validity as a durability analysis method. The MSR method directly calculates the modal displacement time history in multibody dynamics analysis; as a result, the total analysis time is shorter than that of MSM method. We conduct durability analysis using the MSR method and a durability test of a torsion beam axle that is affected by various road loads within the natural frequency of the beam axle. The analysis results for critical location and durability were in good agreement with the respective test results. Therefore, durability analysis using the MSR method is effective in predicting the durability of the structures of various dynamic systems.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.8
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• pp.2167-2176
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• 1994

This paper presents some useful design criteria for the turbine cogeneration system through both the design and off-design analysis. Comparative analysis of the part load performance is carried out for several gas turbines which have different design parameters represented by the turbine inlet temperature and pressure ratio. It is shown that the variation in part load efficiency considerably depends on the design parameter. The off-design operation of the heat recovery steam generator is simulated by introducing adequate assumptions for the heat transfer process. It is turned out that the design parameters of heat recovery steam generator should be determined by considering the favorable operation at the off-design conditions.

• Mass Spectrometry Letters
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• v.5 no.1
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• pp.30-33
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• 2014

A solid phase extraction (SPE) method was optimized for the quantitative analysis of perfluorooctanoic acid (PFOA) in serum using hydrophilic-lipophilic balance SPE and LC-MS/MS. Fetal bovine serums spiked with $^{13}C_8$-PFOA before or after SPE were used as test samples for evaluation of the SPE efficiency. Simultaneous evaluation of matrix effects and absolute SPE recovery for $^{13}C_8$-PFOA in serum using different sample pre-treatments and SPE conditions allowed optimization of SPE process efficiency with minimal matrix effect and decent SPE recovery. Introduction of protein precipitation as a sample pre-treatment procedure for serum samples before SPE generally decreased matrix effect in LC-MS/MS analysis and provided more stable recovery of PFOA.

• 재활복지
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• v.20 no.1
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• pp.87-111
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• 2016

This study is a qualitative case study of 5 substance abusers recovered from drug addiction. It is useful socially and practically to understand about the rehabilitation and its process of recovering from drug addiction. Since this study deals with very private and sensitive issues, qualitative research approach is suitable. Data were collected through one to one in-depth interviews, and were analyzed by using analysis within/cross cases suggested by Creswell(2007). 5 individual cases were presented including substance addicts experiences and recovery process through within-cases analysis. Based on the within-cases analysis, common themes were presented through cross-cases analysis. Total 19 themes, related with recovery from substance addicts, were derived from the five individual cases, and 4 common themes were classified. These 4 common themes were first, recovery of sense of reality, second, taking self-existing pattern, third, self reconstruction in the context of social network, fourth, self-love. Based on the study results and discussions, practical implications were suggested to help persons claiming recovery from substance addicts for their recovery and rehabilitation.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.10
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• pp.18-25
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• 2000

In this paper, we analyze TCP congestion control algorithm over ATM-UBR network. TCP congestion control algorithm consists of slow start, congestion avoidance, fast recovery, fast retransmit. We analyze the ATM-UBR network service using the BSD 4.3 TCP Reno, Vanilla. However we found the fact that the characteristic of fast retransmit, recovery algorithm makes a serious degradation of Performance in multiple losses of packets. We propose new fast retransmit, recovery algorithm to improve the problem. The results of performance analysis improve the multiple losses of packets using a proposed fast retransmit, recovery algorithm.

• 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.