• Journal of Korean Academy of Nursing
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• v.21 no.3
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• pp.281-294
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• 1991

The purpose of this study was to determine the amount of soleus muscle atrophy in rats due to 28 days of decreased activity induced by hindlimb suspension, to observe the restoration of mass and relative muscle weight of the atrophied soleus muscle at day 28 of recovery to control value, and to compare the effect of run training on the mass and relative muscle weight of the atrophied soleus muscle at day 28 of recovery with that of sedentary rats. Adult female Wistar rats were maintained for 28 days with hindlimb suspension. Rats were then assigned randomly to a cage sedentary or running group. Soleus muscle mass and relative muscle weight following hindlimb suspension were compared with a control value. The soleus muscle mass and relative muscle weight of the running and cage sedentary groups following hindlimb suspension were compared with those of a control group. Soleus muscle mass and relative muscle weight of the run training group were compared with those of cage sedentary group. The results obtained were as follows : 1. Soleus muscle mass and relative muscle weight was reduced to 53.28% and 51.11% respectively by hindlimb suspension. 2. Soleus muscle mass and relative muscle weight of the training group t day 28 of recovery was restored to the control value. 3. Soleus muscle mass of the training group was greater than that of the cage sedentary group by 6.6% without statistical significance at day 28 of recovery. 4. Relative soleus muscle weight of the traning group was significantly greater than that of the cage sedentary group by 15.79% From these results, it may be concluded that run training during the posthypokinetic period facilitates the recovery of the atrophied soleus muscle mass of rats.

• Child Health Nursing Research
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• v.21 no.4
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• pp.320-330
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• 2015

Purpose: The purpose of this study was to investigate the use of schoolbags and the prevalence of musculoskeletal symptoms among elementary school children and to identify factors associated with relative schoolbag weight and musculoskeletal symptoms. Methods: A descriptive correlation study was conducted with 228 elementary school children in grades 4-6. A self-administered questionnaire was used for data collection. Descriptive statistics, t-test, ANOVA, $x^2$-test or Fisher's exact test, logistic regression analysis were used for data analysis. Results: Mean relative schoolbag weight (RSW) was 6.40%. Among participants, 13.2% carried more than 10% of their RSW. Only 49.6% of participants organized the contents in their school backpack correctly. Musculoskeletal symptoms were reported by 42.5% of participants. Results from logistic regression analysis identified grade was a significant factor predicting RSW, and gender, RSW, and using a locker were significant factors predicting musculoskeletal symptoms among schoolchildren. Conclusion: Although RSW of school children in this study was within the currently recommended load limit, a considerable proportion of school children were not following guidelines for safe schoolbag use. An effective schoolbag safety campaign for parents, students, and teachers needs to be developed and evaluated to prevent possible musculoskeletal symptoms related to schoolbag use.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.326-330
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• 1988

For the automation of Koji incubation process, microcomputer based Koji incubation system was built and applied to acquisition of the process variables, and to control of the Koji incubation process. The incubation variables included the relative humidity and Koji weight. And data measured were sent to the microcomputer by the interface device built with MC 6821 PIA. Incubation environment conditions -temperature and humidity- were controlled by the actuation of heater and mist sprayer with on/off signal generated by ASIC program. Aspergillus oryzae as a starter of the Koji and steamed barley as media were used and Koji was successfully manufactured both at $25^{\circ}C,\;70%$ RH and at $27^{\circ}C,\;80%$ RH. During the Koji preperation, the temperature was linearly increased and substrate was consumed stepwise showing 3 steps in the weight loss curve.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.401-408
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• 2007

This study examined the histochemical and physiological characteristics during Korean native Ogol chickens (KNOC) development. The body weight, Pectoralis major and soleus muscle weights, and muscle samples were taken at hatching as well as at 3, 5, and 15 weeks of age. The fiber characteristics of the Pectoralis major and soleus muscles from the KNOC at hatching to 15 weeks of age were determined, and the deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein concentrations were measured from the left Pectoralis major muscles. A greater increase in body and muscle weights was detected between hatching and 3 weeks of age than during any other period. Moreover, the cross sectional area (CSA) of the fibers, as well as the total concentration of DNA, RNA, and protein also showed a greater increase betweenhatching and 3 weeks of age than during any other period. The KNOC breed is a dual purpose breed, however, the it has lower body and muscle weights than commercial meat type chickens or layer type chickens. Moreover, the KNOC breed has a small muscle fiber CSA of and a low nucleic acid concentration.

• Journal of Aerospace System Engineering
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• v.14 no.1
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• pp.68-73
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• 2020

This purpose of this paper was to review the development trend of the VTOL MAVs with a ducted propellant that can fly like the VTOL at intermediate and high speeds, hovering, landing, and lifting off vertically over urban areas, warships, bridges, and mountainous terrains. The MAV differs in flight characteristics from helicopters and fixed wings in many respects. In addition to enhancing thrust, the duct protects personnel from accidental contact with the spinning rotor. The purpose of the U.S. Army FCS and DARPA's OAV program is spurring development of a the VTOL ducted MAV. Today's MAVs are equipped with video/infrared cameras to hover-and-stare at enemies hidden behind forests and hills for approximately one hour surveillance and reconnaissance. Class-I is a VTOL ducted MAV developed in size and weight that individual soldiers can store in their backpacks. Class-II is the development of an organic VTOL ducted fan MAV with twice the operating time and a wider range of flight than Class-I. MAVs will need to develop to perch-and-stare technology for lengthy operation on the current hover-and-stare. The near future OAV's concept is to expand its mission capability and efficiency with a joint operation that automatically lifts-off, lands, refuels, and recharges on the vehicle's landing pad while the manned-unmanned ground vehicle is in operation. A ducted MAV needs the development of highly accurate relative position technology using low cost and small GPS for automatic lift-off and landing on the landing pad. There is also a need to develop a common command and control architecture that enables the cooperative operation of organisms between a VTOL ducted MAV and a manned-unmanned ground vehicle.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.363-370
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• 2018

The succulent plants of Echeveria genus are in increasing demand worldwide, but it is difficult to supply good quality young plants throughout the year because propagation efficiencies are depend on cultivar and environmental factors. This study was carried out to investigate the propagation efficiencies of leaf cutting in Echeveria cultivars at different LED light qualities in a closed-type plant factory system. Leaf cuttings cut from stock plants of six difficult-to-propagated cultivars 'Afterglow (AG)', 'Berkeley Light (BL)', 'Mason (MS)', 'Subsessilis Light (SL)', 'Cream Tea (CT)', and 'Ben Badis (BB)' were put into cutting media in the plant factory system maintained at a temperature of $24{\pm}2^{\circ}C$ and relative humidity of $60{\pm}10%$, and watered with over-head irrigation twice a week. Cuttings were irradiated with sole or mixed red (R, 660 nm), blue (B, 450 nm), green (G, 530 nm), and far-red (FR, 730 nm) LEDs as follows: R10, R8+B2, R5+B5, R7+B2+FR1, and R7+B2+G1. PPFD just above the cuttings was $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and photoperiod was 16/8 (light/dark) hours. As a result, propagation efficiencies were dependent on cultivar. Rooting and shooting were relatively easy in 'SL' but shoot formation in 'AG' was very difficult. Light qualities from LEDs also affected plant regeneration. Light conditions with a higher ratio of B, R5+B5, R7+B2+FR1, and R7+B2+G1, promoted shoot formation and growth but inhibited rooting and root growth. R10 and R8+B2 with a higher ratio of R promoted rooting and root growth and inhibited shoot formation and growth of cuttings. In addition, the treatment with FR increased leaf size and biomass of the all plants. Therefore, further studies are needed to investigate the optimum compositions of LED light quality for the improvement of leaf cutting efficiency in difficultto-propagated Echeveria cultivars.