• Structural Engineering and Mechanics
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• v.52 no.6
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• pp.1069-1084
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• 2014

The long-term performance of plates resting on viscoelastic foundations is a major concern in the analysis of soil-structure interaction. As a powerful mathematical tool, fractional calculus may address these plate-on-foundation problems. In this paper, a fractionalized Zener model is proposed to study the time-dependent behavior of a uniformly loaded rectangular thin foundation plate. By use of the viscoelastic-elastic correspondence principle and the Laplace transforms, the analytical solutions were obtained in terms of the Mittag-Leffler function. Through the analysis of a numerical example, the calculated plate deflection, bending moment and foundation reaction were compared to those from ideal elastic and standard viscoelastic models. It is found that the upper and lower bound solutions of the plate response estimated by the proposed model can be determined using the elastic model. Based on a parametric study, the impacts of model parameters on the long-term performance of a foundation plate were systematically investigated. The results show that the two spring stiffnesses govern the upper and lower bound solutions of the plate response. By varying the values of the fractional differential order and the coefficient of viscosity, the time-dependent behavior of a foundation plate can be accurately captured. The fractional differential order seems to be dependent on the mechanical properties of the ground soil. A sandy foundation will have a small fractional differential order while in order to simulate the creeping of clay foundation, a larger fractional differential order value is needed. The fractionalized Zener model is capable of accounting for the primary and secondary consolidation processes of the foundation soil and can be used to predict the plate performance over many decades of time.

• Korean Journal of Veterinary Research
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• v.47 no.4
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• pp.469-473
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• 2007

This study was performed to investigate the effects of urinary acupoint (BL-23, BL-28) by acupuncture (AP) and electroacupuncture (EA) on urinary bladder in dogs. Four healthy male dogs aged within the range of 6~8 months were used in this experiment. For Electrodes implantation on the bladder, dogs were to undergo surgical operation. The purpose of investigating the effect on urinary bladder was to evaluate electromyogram (EMG) changes according to AP or EA at Shen Shu (BL-23), Pang Guang Shu (BL-28) and non-acupoint. AP and EA (2~4 V, 10 Hz) were applied for 20 min to each point. EMG was evaluated when acupuncture began stimulation and as soon as the stimulation by electroacupuncture was gone. By the experiment of investigating the effect of urinary time it was estimated to measure time up to urination from stimulation on effective acupoint, after saline was filled with 70% of whole volumes on urinary bladder. The wave of EMG on resting stage showed simple and regular, whereas that of EMG on urination showed irregularly strong peaks before urination. Acupuncture of BL-28 had an influence on changes of EMG which had irregular peaks on urination. But the changes of EMG after acupuncture of BL-28 and control were regular like resting stage. The changes of EMG after EA at BL-23 and BL-28 showed irregularly a variety of wave forms. The interval through urination from stimulation at BL-28 and control become short as measuring time by EA (p<0.01). According to the results, AP at BL-28 was effective to urinary bladder. EA at BL-23 and BL-28 was effective to urinary bladder. Especially, the interval on stimulating at BL-28 by EA was the shortest in measuring time to urination from stimulation.

• The Korean Journal of Ecology
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• v.26 no.1
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• pp.1-4
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• 2003

In diurnal activity of the black-crowned night herons on breeding season, activity budget was that male were standing(29.5%), preening(21.5%), comfort(10.9%), and female were resting(26.3%), repairing (18.4%), preening(15.3%) in sequence. Activity budget was high significant between male and female(p<0.01). In case of activity-time budget sequence, male was standing(38.7%), locomotion(33.8%), preening(11.5%), and female was resting(55.4%), standing(18.4%), preening(9.4%). Therefore, activity-time budget was significantly different in male and female(p<0.01).

• Animal Bioscience
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• v.35 no.7
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• pp.1039-1047
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• 2022

Objective: The purpose of this study is to determine the optimal time of transportation of floor-feed and scatter-feed broilers. Methods: Eighty healthy Arbor Acres (AA) broilers (21-day-old, 624.4 g, male, standard error = 6.65) were selected and randomly divided into two experimental groups (floor-feed and scatter-feed), then fed for three weeks. The experiment comprised a 2×4 factorial design with 2 feed patterns (floor-feed and scatter-feed) and 4 transport periods (2, 3, 4, and 5 h), and 4 replicates of 5 broilers (54-day-old, 2243 g, standard error = 46.65) was used to compare weight loss, meat quality and behavior index of different groups. Results: It appeared that drip loss, meat color and resting behavior of experimental broilers changed as length of transportation (p<0.05), however, weight loss and pH were not significantly transformed (p>0.05). Compared with floor-feed group, broilers in scatter-feed group had lower pH at 24 hours (3 h) and different behavioral indicators (p<0.05). Especially indicators after 3 h transportation, there were obvious differences between the two feeding modes in the behavior reaction of stress events before slaughter with different transport duration (p<0.05). The fluctuation of data on resting behavior with scatter-feed was significantly higher than that of floor-feed broilers. There was no interaction between transport time and different feeding methods for index tested of our experiment (p>0.05). Conclusion: Comprehensive analysis showed that the maximum transport duration of floor-feed and scatter-feed broilers should not exceed 3 h, and scatter-feed broilers were more likely prone to fear.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.6
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• pp.547-554
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• 1999

The aim of the present study is to investigate the contribution of $Ca^{2+} ?activated\;K^+\;(K_{Ca})$ channels and delayed rectifier $K^+\;(K_V)$ channels to the resting membrane potential (RMP) in rabbit middle cerebral arterial smooth muscle cells. The RMP and membrane currents were recorded using the whole-cell patch configuration and single $K_{Ca}$ channel was recorded using the outside-out patch configuration. Using the pipette solution containing 0.05 mM EGTA, the RMP was $-25.76{\pm}5.08$ mV (n=12) and showed spontaneous transient hyperpolarizations (STHPs). The membrane currents showed time- and voltage-dependent outward currents with spontaneous transient outward currents (STOCs). When we recorded the membrane potential using the pipette solution containing 10 mM EGTA, the RMP was depolarized and did not show STHPs. The membrane currents showed no STOCs but only showed slowly inactivating outward currents. External TEA (1 mM) reversibly inhibited the STHPs, depolarized the RMP, reduced the membrane currents, abolished STOCs, and decreased the open probability of single $K_{Ca}$ channel. When $K_V$ currents were isolated, the application of 4-AP (5 mM) depolarized the RMP. The important aspect of our results is that $K_{Ca}$ channel is responsible for the generation of the STHPs in the membrane potential and plays an important role in the regulation of the RMP and $K_V$ channel is also responsible for the regulation of the RMP in rabbit middle cerebral arterial smooth muscle cells.

• Structural Engineering and Mechanics
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• v.56 no.1
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• pp.27-47
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• 2015

In this study, the accuracy and reliability of fully nonlinear method against equivalent linear method for dynamic analysis of soil-structure interaction is investigated comparing the predicted results of both numerical procedures with the results of experimental shaking table tests. An enhanced numerical soil-structure model has been developed which treats the behaviour of the soil and the structure with equal rigour. The soil-structural model comprises a 15 storey structural model resting on a soft soil inside a laminar soil container. The structural model was analysed under three different conditions: (i) fixed base model performing conventional time history dynamic analysis, (ii) flexible base model (considering full soil-structure interaction) conducting equivalent linear dynamic analysis, and (iii) flexible base model performing fully nonlinear dynamic analysis. The results of the above mentioned three cases in terms of lateral storey deflections and inter-storey drifts are determined and compared with the experimental results of shaking table tests. Comparing the experimental results with the numerical analysis predictions, it is noted that equivalent linear method of dynamic analysis underestimates the inelastic seismic response of mid-rise moment resisting building frames resting on soft soils in comparison to the fully nonlinear dynamic analysis method. Thus, inelastic design procedure, using equivalent linear method, cannot adequately guarantee the structural safety for mid-rise building frames resting on soft soils. However, results obtained from the fully nonlinear method of analysis fit the experimental results reasonably well. Therefore, this method is recommended to be used by practicing engineers.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.283-290
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• 2018

BACKGROUND/OBJECTIVES: Indirect calorimetry is the gold-standard method for the measurement of resting energy expenditure. However, this method is time consuming, expensive, and requires highly trained personnel. To overcome these limitations, various predictive equations have been developed. The objective of this study was to assess the validity of predictive equations for resting energy expenditure (REE) in Korean non-obese adults. SUBJECTS/METHODS: The present study involved 109 participants (54 men and 55 women) aged between 20 and 64 years. The REE was measured by indirect calorimetry. Nineteen REE equations were evaluated for validity, by comparing predicted and measured REE results. Predictive equation accuracy was assessed by determining percent bias, root mean squared prediction error (RMSE), and percentage of accurate predictions. RESULTS: The measured REE was significantly higher in men than in women (P < 0.001), but the difference was not significant after adjusting for body weight (P > 0.05). The equation developed in this study had an accuracy rate of 71%, a bias of 0%, and an RMSE of 155 kcal/day. Among published equations, the $FAO_{weight}$ equation gave the highest accuracy rate (70%), along with a bias of -4.4% and an RMSE of 184 kcal/day. CONCLUSIONS: The newly developed equation provided the best accuracy in predicting REE for Korean non-obese adults. Among the previously published equations, the $FAO_{weight}$ equation showed the highest overall accuracy. Regardless, at an individual level, the equations could lead to inaccuracies in a considerable number of subjects.

• Physical Therapy Korea
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• v.9 no.2
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• pp.107-113
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• 2002

This study was conducted to determine the effects of deep breathing exercise and ankle exercise on blood flow velocity in the femoral vein. Sixteen healthy male students were recruited from Yonsei University, at Wonju. The blood flow velocities in the femoral vein were measured under three different conditions: resting, deep breathing, and ankle exercise. All subjects were given a 5-minute relaxing time in supine position prior to the study. Using a doppler ultrasound with a 8 MHz probe, the peak blood flow velocities were collected in a twenty-second-period at each condition. The subjects took a rest in between trials for the blood flow to return to its resting levels. The result showed a significant difference in peak blood flow velocities under those three conditions (p<.001). The peak blood flow velocity was highest in ankle exercise condition. The peak blood velocity was significantly higher in deep breathing condition compared with the resting condition. As a result, it is revealed that not only the muscular contractions but also the deep breathing exercises induced facilitating effects of venous return. Either of the exercise methods can be recommended to prevent blood stasis in patients with risk of deep vein thrombosis after cardiac or lower extremity surgery.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.474-481
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• 2010

The sperm collection time, sex steroid hormones, and gonadal development of protandrous black porgy, Acanthopagrus schlegeli, acclimated in freshwater for more than 2 years were investigated to evaluate its reproductive capability. The gonadal development of black porgy reared in seawater and freshwater could each be classified into four successive stages. For black porgy reared in seawater (BSW) as the control, these were the growing (December to February), mature (February to March), spent (March to June), and degeneration and resting (July to December) stages; for black porgy reared in freshwater (BFW), these were the growing (November to January), mature (January to February), spent (February to May), degeneration and resting (June to November) stages. In both BSW and BFW, the plasma cortisol levels were the highest in March. The plasma testosterone (T) levels of BSW and BFW were the highest in March and February, respectively. The plasma estradiol-$17{\beta}$ ($E_2$) levels did not differ significantly between BSW and BFW. The 11-ketotestosterone (11-KT) levels in the plasma of BSW and BFW were the highest in April. Sperm was collectible from March to June in BSW and from February to May in BFW. The results indicated that the gonadal maturation of BFW was about 1 month faster than that of BSW.

• PNF and Movement
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• v.15 no.1
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• pp.35-40
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• 2017

Purpose: The purpose of this study was to determine the immediate effects of using the proprioceptive neuromuscular facilitation (PNF) contract-relax technique in the close kinetic chain position on the gait ability and gastrocnemius muscle tone of stroke patients. Methods: The subjects were patients who had strokes due to cerebrum infarction and hemorrhage. The subjects participated in exercise with the PNF contract-relax technique in the standing-on-elbow position with a high table, and the affected lower leg was placed in the posterior position. The PNF contract-relax technique was applied at the position in which the ankle plantar-flexors were in a sufficiently elongated position. After performing twice in each range, while the muscle was elongated, the affected side was moved further back and a new range was set. In each session, the time of contraction was set to 8 seconds, and the resting time was set to 5 seconds; however, if the patient felt tired, they received more resting time during the intervention. The Myoton Pro and 10 m walking test were used to measure the muscle tone and gait ability both pre- and post-intervention. Results: After participating in the program, the muscle tone decreased and the gait ability improved in the ankle plantar-flexors, as determined by the Myoton Pro and 10 m walking test. Conclusion: The PNF contract-relax technique can help to decrease muscle tone in ankle plantar-flexors with hypertonus and increase the gait ability in stroke patients.