• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.5
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• pp.81-92
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• 2011

In this paper, a new method to estimate the number of MU (motor unit) related to the widths and distribution of end plate in NMJ (neuromuscular junction) of biceps brachii is proposed by varying muscle parameter statistically in EMG model. This work is done by designing MU-simulator and EPZ-simulator. The proposed method was compared with the results of previous researchers. The proposed MU-simulator generates SMUAP (single motor unit action potential) and CMAP (compound muscle action potential) signal similar to detected SMUAP and CMAP signal obtained from muscle. The EPZ-simulator estimate the numbers of MU by varying the widths and distribution of end plate in neuromuscular junction of muscle. The results shows that the numbers of MU was estimated about 450 ea. and muscle fibers was about 340 ea., end plate widths was about 6 mm, and end plate was randomly distributed. The proposed method may be comparable with the method of anatomical studies.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.606-614
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• 2018

It is important to understand how marbling traits and tenderness differ among beef steaks from the carcass grading site and other regions within the longissimus thoracis (LT) muscle, as these characteristics are closely associated with consumer acceptability and willingness to purchase. Thus, the aim of this study was to compare the marbling fleck traits and objective tenderness parameters in the groups classified by the coarseness index (CI) of marbling fleck (high and low groups) at the carcass grading site ($13^{th}$ thoracic vertebra; 13T) and three different locations (13T, 9T, and 6T) within the LT muscle from well-marbled (marbling score 7 to 9) Hanwoo steer. Image analysis showed that the longitudinal locations had a significant effect on marbling fleck traits. The total area of large marbling fleck divided by the total marbling area (coarseness) was higher at the central region (13T to 12T) compared to the front thoracic region (6T to 5T) in the high CI group (0.23 vs. 0.17, p<0.05), whereas no significant differences were observed in the total number of marbling fleck within the LT muscle in the high or low CI groups (p>0.05). Location effect on objective tenderness parameters within the LT muscle was somewhat limited, although the high CI group had a lower Warner-Bratzler shear force (WBS) value than did the low group (p<0.05). Taken together, the degree of coarseness of marbling fleck decreased from the carcass grading site to the front thoracic site, whereas the objective tenderness parameters, including WBS and hardness, of the grading site did not differ from the other regions within the LT muscle.

• Journal of Animal Science and Technology
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• v.50 no.3
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• pp.293-300
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• 2008

Muscle fat content including intramuscular fat content(IMF) is the most important parameter in meat quality of cattle. Triacylglycerol is the major component of fat and is found in adipocyte and skeletal muscle. In present study, we carried out the determined of triacylglycerol contents and mRNA expression patterns of genes related with triacylglycerol biosynthesis such as ACSS2, GPAT, MGAT and DGAT in Hanwoo longissimus muscle using the real-time PCR. The triacylglycerol contents were continuously increased during the fattening stages. Interestingly, the contents of triacylglycerol were 7.4 fold higher(0.34 vs. 2.51, P<0.01) in 27 months old group than 12 months old group. The mRNA levels of ACSS2, GPAT and DGAT genes were also increased during fattening stages, whereas that of MGAT gene did not show difference among the stages. Thus, these results suggested that increasing of the triacylglycerol contents in longissimus muscle during fattening stages may be related with increased expressions of triacylglycerol biosynthesis genes(ACSS2, GPAT and DGAT). These results will be helpful to understand the mechanism of muscle fat deposition in skeletal muscle.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.171-179
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• 2004

The purpose of this study is to generate cycling motion for FES (functional electrical stimulation) using knee muscles only. We investigated the possibility by simulation. The musculoskeletal model used in this simulation was simplified as 5-rigid links and 2 muscles (knee extensor and flexor). For the improvement of the present feedforward control in FES, we included feedback path in the control system. The control system was developed based on the biological neuronal system and was represented by three sub-systems. The first is a higher neuronal system that generates the motion command for each joint. The second is the lower neuronal system that divides the motion command to each muscle. And the third is a sensory feedback system corresponding to the somatic sensory system. Control system parameters were adjusted by a genetic algorithm (GA) based on the natural selection theory. GA searched the better parameters in terms of the cost function where the energy consumption, muscle force smoothness, and the cycling speed of each parameter set (individual) are evaluated. As a result, cycling was implemented using knee muscles only. The proposed control system based on the nervous system model worked well even with disturbances.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.2
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• pp.297-309
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• 1998

Numerical parameters have been developed to diagnose L4/L5 disc patients during repetitive flexions and extensions. Electromyography(EMG) has been used to define the muscle excitation and movement cycle in this study. Twenty healthy subjects and twenty L4/L5 disc patients were recruited for the experiment. The subjective pain levels of patients were recorded as $3.7{\pm}1.6$ according to visual analogue scale where 10 was the maximum pain level. Variance ratio of motion cycle was suggested as a new parameter to examine the consistency of the trunk movement. The results indicated that the temporal EMG pattern such as peak time difference between Quadriceps and Hamstrings, the duration of coexcitation between Erector spinae and Rectus abdominis muscle pairs showed a statistically significant difference between healthy subjects and patients. Variance ratio of External oblique and Internal oblique also showed a statistically significant difference. It is expected that those results could be used for diagnosis by building a database for various back pain patients and healthy subjects. This method can eventually help physicians for early diagnosis and prevention of low back disorders.

• Journal of Biomedical Engineering Research
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• v.17 no.2
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• pp.221-226
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• 1996

Tendon reflex responses generated from mechanical stimulus had been studied for quantitative analysis of activity of tendon reflex, especially patellar tendon reflex responses are known to be a criterion for diagnosing the L3 or L4 radiculopathy. In this paper, we developed a digital signal processing system for analysis of the tendon reflex response. The system parameter, i.e., $\textit{sampling frequency, pre-amplification gain, input channel and filter bank}$ are selected by Using software switches. From the view points of flexibility, the system hardware is connected to an IBM PC for analyzing the tendon reflex parameters, amplitude, latency duration We applied the proposed system to the analysis of the patellar tendon reflex reponses. In the experiment, we measured latency, duration, amplitude of the reflex action potentials generated from vastus medialis, vastus lateralis and rectus femoris that compose quadriceps, and the measured data are analyzed througll the ANOVA test which has 5% significant level. As a result, we showed that the mean amplitude of reflex action potential at the vastus lateralis is larger than any other muscle and the mean latency of the reflex action potential at the rectus femoris is shorter than any other muscle.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.9-13
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• 1997

The present study was designed to develop the functional electrical stimulation system in order to restore motor function of paralytic patients. We attempt to establish adequate stimulus parameters for the recovery of work unction in lower limb paralysis patients and to develop the electrical stimulation system, which is effective to protect foot drop in these patients. In our animal and human experiment, adequate stimulus condition for surface electrode on the lower limb were 0.2-0.3ms at the duration and 50 Hz, which contain 600Hz train pulse. This parameter has efficiently prevented the foot drop from lower limb paralysis, decreased muscle fatigue and induced powerful contraction of lower limb muscle.

• Journal of Biomedical Engineering Research
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• v.18 no.4
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• pp.413-420
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• 1997

In this paper, we analyzed the contraction patterns of active elbow muscles during isometric, concentric and eccentric contraction. The analysis parameters consist of frequency domain parameters (mean frequency, median frequency, peak frequency, peak power, skewness, kurtosis) and time domain paraseters (zero crossing, positive maxima, integrated EMG). The results of this study were as follows; The BR/BB of isometric contraction appeared to be Venter as the elbow joint was more extended. The BR /BB during concentric and eccentric contraction tended to increase with more extension of the elbow joint angle, but there was no significant difference between concentric and eccentric contraction. Further, the EMG power spectrum due to the type of contraction were different betwen eccentric and concentric contraction. According to the results, it was found that the activation pattern in elbow flexor muscles was different during three different muscle contraction pattern. Therefore, elbow flexor muscles should not be considered a single functioning unit. Especially, at the time domain analysis, IEMG is a dominant parameter for analysis of activation patterns, and the skewness kurtosis can be useful parameters in functional recognition for prosthesis control purpose.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.123-128
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• 1996

Tenderness of loin and brisket muscles of Korean and imported beef was measured using the Time-lntensity (Tl) techniques. From the Tl curve, the Rx, Imax, Dur and AUC parameters were determined. For the loin muscle, Korean beef showed significantly (p < 0.05) larger Rx, Imax, and AUC. This result represents Korean beef loin has higher tenderness than that of imported one. For the brisket muscle, imported beef show.

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.411-418
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• 2021

The purpose of this study was to find out the effects of isomatric and isotonic exercise on the muscle function and cytokine which will prevent recurrence of breast cancer patients. A subjects were thirteen breast cancer patients and they were randomly assigned either isometric exercise group(n=10), isotonic exercises group(n=10) or a daily base care control group(n=10). Resistance exercise group did a exercise program with 60~70%RM for 60min, 3days per week during 8week. There were significantly difference between groups which were showing a increasing flexion, abduction, external rotation, IL-6 and IL-10 in isotonic exercise.