• 제어로봇시스템학회논문지
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• 제10권11호
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• pp.1006-1011
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• 2004

Carbon nanotubes have outstanding properties which make them useful for a number of high-technology applications. Especially, single-walled carbon nanotube (SWNT), working under physical conditions (in aqueous solution) and converting electrical energy into mechanical energy directly, can be a good substitute for artificial muscle. The carbon nanotube structure simulated in this paper is an isotropic cantilever type with an adhesive tape which is sandwiched between two SWNTs. For predicting the geometrical and physical parameters such as deflection, slope, bending moment and induced force with various applied voltages, the analytical model for a 3 layer bimorph nanotube actuator is developed by applying Euler-Bernoulli beam theory. The governing equation and boundary conditions are derived from energy Principles. Also, the brief history of carbon nonotube is overviewed and its properties are compared with other functional materials. Moreover, an electro-mechanical coupling coefficient of the carbon nanotube actuator is discussed to identify the electro-mechanical energy efficiency.

• 로봇학회논문지
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• 제16권1호
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• pp.17-22
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• 2021

Soft robot research has been actively conducted due to the advantages of soft materials that have less motion restrictions and higher energy efficiency compared to rigid robots. In particular, soft robots are being applied in more and more diverse fields, and the need for soft robots is increasing, especially when dealing with soft or deformable objects that rigid robots cannot perform. Various soft robots are being developed, and studies on artificial muscles with versatility, seamless integration with sensing, and self-healing capabilities are being proposed. In this study, we propose one of the most simple rectangular shaped HASEL (Hydraulically amplified self-healing electrostatic) actuators and compare the performance according to shape deformation such as the size or ratio of actuators and electrodes. Developing these actuators can be used in many ways for artificial muscles in soft robotics.

• 한국의류학회지
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• 제41권1호
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• pp.184-195
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• 2017

Baseball is a life sport that gives vitality to people. However, currently available leg guards do not have a variety of sizes and it is very difficult to purchase a leg guard that is suitable for the size of a specific consumer. Therefore, this study investigated the size system of a leg guard sold in the market and suggested a grading deviation suitable for the legs of Korean males. The results of the study were as follows. First, most brands were sold only in three size systems as children's, teenagers, and adults. Adult size systems were not subdivided. Second, Korean male legs were classified into Group 1 (large girth and height and lower body muscle) and Group 2 (small girth and height and low underbody muscle). Third, the size system is based on vertical items such as height and mid-thigh circumference. Each group produced 10 sizes. The smallest height or the largest height was also found to be about 4.5 to 5.0cm smaller or larger than the sample size for each group. The total length of the leg guard was about 2.5cm when the height was increased or decreased by one size. It was confirmed that the deviation of the circumference of the mid-thigh should be about 2.0cm larger or smaller than the sample size even if the height is the same. The deviation of the knee circumference and ankle circumference was smaller than the other circumference. In conclusion, the dimension combinations of the leg guard must be set differently to provide a leg guard with high size suitability according to leg type.

• Asian-Australasian Journal of Animal Sciences
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• 제28권7호
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• pp.1020-1027
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• 2015

The combined effect of tumbling marination methods (vacuum continuous tumbling marination, CT; vacuum intermittent tumbling marination, IT) and effective tumbling time (4, 6, 8, and 10 h) on the water status and protein properties of prepared pork chops was investigated. Results showed that regardless of tumbling time, CT method significantly decreased the muscle fiber diameter (MD) and significantly increased the total moisture content, product yield, salt soluble proteins (SSP) solubility, immobilized water component (p<0.05) compared with IT method. With the effective tumbling time increased from 4 h to 10 h, the fat content and the MD were significantly decreased (p<0.05), whereas the SSP solubility of prepared pork chops increased firstly and then decreased. Besides, an interactive effect between CT method and effective tumbling time was also observed for the chemical composition and proportion of immobilized water (p<0.05). These results demonstrated that CT method of 8 h was the most beneficial for improving the muscle structure and water distribution status, increasing the water-binding capacity and accelerating the marinade efficiency of pork chops; and thus, it should be chosen as the most optimal treatment method for the processing production of prepared pork chops.

• 대한기관식도과학회지
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• 제12권2호
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• pp.19-25
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• 2006

There have been numerous modalities to recover blink function of orbicularis oculi muscle in patients with facial paralysis. However, there is still no optimal method for reanimation of eyelid. In this study, we tried to recover blink function of paralyzed rabbit's eyelid with the ion polymer metal composite (IPMC) which is one of the electroactive polymers that is spotlighted as artificial muscle. We manufactured IPMC by plating the platinum over perfluorosulphonic acid polymer ($Nafion^{(R)}$). IPMC was coated by Norland optical adhesive for the purpose of insulation and keeping it from dry. IPMC modifications by roughening the surface of Nafion, repetitive plating (maximum 4 times) with platinum, and lengthening the width of IPMC were done. The facial paralysis was induced in the rabbit by sectioning of facial nerve at the main trunk. After minimum period of 4 weeks, IPMC was inserted in the paralyzed rabbit's eyelid. By modification, the force generated by IPMC was enhanced. Restoration of blink function in paralyzed rabbit was achieved on electrical stimulation of the IPMC by 5 voltage direct current. IPMC can be promising option for facial reanimation, but further studies are needed to enhance the efficiency of IPMC.

• 한국수산과학회지
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• 제39권6호
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• pp.454-459
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• 2006

A simultaneous high-performance liquid chromatography assay method for amoxicillin and ampicillin in fish products was developed, evaluated, and validated by monitoring these antibiotics in fish samples obtained from aquaculture and distribution. The recovery rate of this method was higher than those of conventional methods and was 95.3-106.6% for amoxicillin and 81.4-92.4% for ampicillin. Our pretreatment procedure sufficiently removed or reduced materials affecting HPLC analysis, such as low-molecular-weight substances. The performance limit of this method was evaluated as 0.01 ppm of amoxicillin and ampicillin in fish muscle. Finally, 171 fish samples, including olive flounder (Paralichthys olivaceus), common sea bass (Lateolabrax japonicus), and black rock fish (Sebastes schlegeli) collected from fish farms in the coastal area between April and September 2005 were analyzed to evaluate the overall efficiency of the method and to monitor the actual of amoxicillin and ampicillin usage in fish farms. The results indicated that the developed method was suitable for analyzing amoxicillin and ampicillin in fish muscle, and determined that those antibiotics were being used for fish farming but were not detected in fish samples during the shipping and distribution stages.

• 대한기계학회논문집A
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• 제31권1호
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• pp.36-42
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• 2007

This paper presents mechanical design, fabrication and test of a biomimetic fish robot actuated by a unimorph piezoceramic actuator, LIPCA(Lightweight Piezo-Composite curved Actuator.) We have designed a linkage mechanism that can convert bending motion of the LIPCA into the caudal fin movement. This linkage system consists of a rack-pinion system and four-bar linkage. Four types of artificial caudal fins that resemble caudal fin shapes of ostraciiform subcarangiform, carangiform, and thunniform fish, respectively, are attached to the posterior part of the robotic fish. The swimming test under 300 $V_{pp}$ input with 0.6 Hz to 1.2 Hz frequency was conducted to investigate effect of tail beat frequency and shape of caudal fin on the swimming speed of the robotic fish. At the frequency of 0.9 Hz, the maximum swimming speeds of 1.632 cm/s, 1.776 cm/s, 1.612 cm/s and 1.51 cm/s were reached for fish robots with ostraciiform, subcarangiform carangiform and thunniform caudal fins, respectively. The Strouhal number, which means the ratio between unsteady force and inertia force, or a measure of thrust efficiency, was calculated in order to examine thrust performance of the present biomimetic fish robot. The calculated Strouhal numbers show that the present robotic fish does not fall into the performance range of a fast swimming robot.

• Asian-Australasian Journal of Animal Sciences
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• 제15권1호
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• pp.72-78
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• 2002

The effects of housing and nutrition on the performance of growing gilts of the Nepalese Pakhribas breed were investigated. A total of 36 pigs were allocated according to a factorial design with 3 levels of nutrition, provided to achieve a target growth rate of 200, 300 or 400 g/day, and two types of housing, traditional or improved. The growth rate and body composition were monitored during the growing period and subsequent pregnancy. There was a significantly higher growth rate (p<0.01), greater $P_2$ backfat thickness (p<0.01), and greater eye muscle depth (p<0.01) at service in pigs given the higher level of nutrition. Similarly, there was a significantly higher growth rate (p<0.05), and greater eye muscle depth (p<0.10) with improved housing but no significant difference in $P_2$ backfat thickness. The conception rate was 90% at first service, with no difference between treatments. Gilts from the high plane of rearing produced a mean litter size of one piglet greater than those on the low plane, but this was not significant with the limited numbers. However, both improved plane of nutrition and reduced climatic penalty by improving housing resulted in increased birthweight of piglets (p<0.05). It is concluded that improvement in housing can give benefits equivalent to at least a 7% improvement in efficiency of feed use under traditional Nepalese circumstances for pig rearing.

• 한국동물학회지
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• 제23권3호
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• pp.137-148
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• 1980

토끼 골격근 小胞體의 ATPase 活性에 미치는 $Hg^{2+}, Cu^{2+}, Pb^{2+}, Cd^{2+}, Mn^{2+}$ 등 2價 陽이온을 영향을 비교 측정하였다. 이들 陽이온은 $Mn^{2+}$을 제외하고 모두 이 酵素의 活性을 阻害하였다. $Mn^{2+}$은 低濃度 (12.5-100 $\mu$M)에서는 오히여 活性을 증가시켰고, 그 보다 高濃度에서는 극히 약하게 阻害하였다. $Mn^{2+}$을 제외한 위의 2價 陽이온들의 阻害龍은 $Hg^2$가 가장 컸고 (阻害係數 Ki = 10$\mu$M), rm 다음이 $Cu^{2+}$ (Ki = 30$\mu$M), $Pb^{2+}$ (Ki = 120$\mu$M), $Cd^{2+}$ (Ki = 320$\mu$M)의 순이었다. 위의 4종의 陽이온들의 ATPase에 대한 阻害作用을 可逆的 非競爭的 阻害로 판정되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권3호
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• pp.406-413
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• 2014

A study was conducted to compare the effect of halal slaughter without stunning and gas stun killing followed by bleeding on residual blood content and storage stability of rabbit meat. Eighty male New Zealand white rabbits were divided into two groups of 40 animals each and subjected to either halal slaughter without stunning (HS) or gas stun-kill (GK). The volume of blood lost during exsanguination was measured. Residual blood was further quantified by determination of haemoglobin content in Longissimus lumborum (LL) muscle. Storage stability of the meat was evaluated by microbiological analysis and measuring lipid oxidation in terms of thiobarbituric acid reactive substances (TBARS). HS resulted in significantly higher blood loss than GK. HS had significantly lower residual haemoglobin in LL muscle compared to GK. Slaughter method had no effect on rabbit meat lipid oxidation at 0, 1, and 3 d postmortem. However, at 5 and 8 days of storage at $4^{\circ}C$, significant differences (p<0.05) were found, with meat from the GK group exhibiting significantly higher levels of MDA than that from HS. At day 3, greater growth of Pseudomonas aeroginosa and E. coli were observed in the GK group (p<0.05) with B. thermosphacta and total aerobic counts remained unaffected by slaughter method. At days 5 and 7 postmortem, bacterial counts for all tested microbes were affected by slaughter method, with GK exhibiting significantly higher growth than HS. It can be concluded that slaughter method can affect keeping quality of rabbit meat, and HS may be a favourable option compared to GK due to high bleed out.