• Food Science of Animal Resources
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• v.34 no.6
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• pp.769-776
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• 2014

The goat placenta was fermented by Bacillus subtilis and the optimal fermentation parameters of strongest antioxidant capacity of peptides were obtained using response surface methodology (RSM). The effects of fermentation time, initial pH value and glucose content on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity of the goat peptides were well fitted to a quadric equation with high determination coefficients. According to the data analysis of design expert, the strongest DPPH radical scavenging capacity value was obtained with the following conditions: content of glucose was 2.23%, initial pH value was 7.00 and fermentation time was 32.15 h. The DPPH radical scavenging capacity commonly referring antioxidant activity showed a concentration dependency and increased with increasing peptide concentration. The effects of temperature and pH were assessed to determine the stability of antioxidant peptides prepared from goat placenta. Antioxidant peptides showed good stabilities when temperature was lower than $70^{\circ}C$. However, the antioxidant peptides lost antioxidant activities rapidly under alkaline and excessive acid condition. Ultrafiltration technique was performed to separate fermentation broth with different Mw (molecular weight). It was found that peptides in the range of < 3 KDa mainly accounted for the antioxidant activities.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.8
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• pp.753-757
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• 2015

This paper introduces an experimental rescue robot, HUBO T-100 and presents the optimal motion control method. The objective of the rescue robot is to extract patients or wounded soldiers in the battlefield and hazardous environments. Another mission is to dispose and transport an explosive ordnance to safe places. To execute these missions, the upper body of the rescue robot is humanoid in form to execute various kinds of tasks. The lower body features a hybrid tracked/legged design, which allows for a variety of mode of locomotion, depending on terrain conditions in order to increase traversability. The weight lifting motion is one of the most important task for performing rescue related missions because the robot must lift an object or impaired person lying on the ground for transferring. Here, dynamics based motion optimization is employed to minimize joint torques while maintaining stability simultaneously. Physical experiments with a real humanoid robot, HUBO T-100, are presented to verify the proposed method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.7
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• pp.560-570
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• 2013

In this paper, we propose transceiver design strategies for the two-cell multiple-input multiple-output (MIMO) interfering broadcast channel where inter-cell interference (ICI) exists in addition to inter-user interference (IUI). We first formulate the generalized zero-forcing interference alignment (ZF-IA) method based on the alignment of IUI and ICI in multi-dimensional subspace. We then devise a minimum weighted-mean-square-error (WMSE) method based on "regularizing" the precoders and decoders of the generalized ZF-IA scheme. In contrast to the existing weighted-sum-rate-maximizing transceiver, our method does not require an iterative calculation of the optimal weights. Because of this, the proposed scheme, while not designed specially to maximize the sum-rate, is computationally efficient and achieves a faster convergence compared to the known weighed-sum-rate maximizing scheme. Through analysis and simulation, we show the effectiveness of the proposed regularized ZF-IA scheme.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.6
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• pp.98-105
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• 2019

In order to improve the fuel economy and dynamic behavior of automobiles, the weight reduction tendency of automobile parts is obvious. Also, in order to maximize assembly and maintenance convenience, various parts are integrated and modularized. Multi-piece methods require many manufacturing processes and become a factor of lowering the strength of parts. It is advantageous to overcome the disadvantages by integrally manufacturing to reduce the processing steps and ensure the strength of the parts. However, when it is necessary to process in a narrow space inside the part, it is impossible to process with the existing spindle. The angle head spindle is only a component of a machine tool, but it is a core part that requires high technology and is highly utilizable in products requiring high precision machining. Therefore, various and continuous studies needs for angle head spindles in areas such as vibration absorption, operational safety, excellent dimensional stability, and strength. In this paper, we propose an optimal design for angle head spindle by performing structural analysis and shape optimization for angle head spindle gear and case.

• Structural Engineering and Mechanics
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• v.83 no.5
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• pp.655-669
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• 2022

Passive vibration control devices like tuned liquid column dampers (TLCD) not only significantly reduce buildings' vibrations but also can serve as a water storage facility. The recently introduced modified form of TLCD known as tuned liquid column ball damper (TLCBD) suppressed external vibration efficiently compared to traditional TLCD. For excellent performance, the mass ratio of TLCBD should be in the range of 5% to 7%, which does not include the mass of the ball. This additional mass of the ball increases the overall structure mass. Therefore, in this paper, an effort is made to reduce the mass of TLCBD. For this purpose, a new modified version of TLCBD known as tuned liquid column hollow ball damper (TLCHBD) is proposed. The existing mathematical modeling of TLCBD is used for this new damper by updating the numerical values of the mass and mass moment of the ball. Analytically the optimal design parameters are obtained. Numerically the TLCHBD is investigated with a single degree of freedom structure under harmonic and seismic loadings. It is found that TLCHBD performance is similar to TLCBD in both loadings' cases. To validate the numerical results, an experimental study is conducted. The mass of the ball of TLCHBD is reduced by 50% compared to the ball of TLCBD. Both the arrangements are studied with a multi-degree of freedom structure under harmonic and seismic loadings using a shake table. The results of the experimental study confirm the numerical findings. It is found that the performance behavior of both the dampers is almost similar under harmonic and seismic loadings. In short, the TLCHBD is lighter in weight than TLCBD but has a similar vibration suppression ability.

• Journal of Veterinary Clinics
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• v.39 no.6
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• pp.294-301
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• 2022

Three-dimensional (3D) printing technique has been widely used for accurate screw and pin placement in orthopedic surgery and neurosurgery. However, there are few reports comparing the accuracy between the patient-specific guides and freehand Kirschner wire (K-wire) placement in toy, small and medium breed dogs. This study aimed to assess the accuracy of 3D printed patient-specific guides (PSGs) in pin insertion in the thoracolumbar vertebrae of toy breed dogs and compare the outcomes between novice and experienced surgeons. The experiment was conducted on the thoracolumbar vertebrae of 21 euthanized toy breed dogs (median weight, 5.95 kg). The optimal insertion angle placement was determined and patient-specific guides for K-wire insertion were designed and 3D printed using computed tomography (CT) and a 3D computer-aided design program of three vertebrae (Thoracic 12-Lumbar 1). K-wire tracts were made by experienced and novice surgeons and compared to assess the accuracy based on postoperative CT. Based on postoperative CT, in the experienced group, 61 out of 63 pins (96.8%) were fully contained inside the vertebral body and lamina, whereas two pins (3.2%) had perforated the vertebral canal (grade 3, 2-4 mm breach). However, all the pins in the novice group were fully contained. The use of 3D printed PSGs for pin insertion in the thoracolumbar region is an accurate and safe alternative to freehand screw placement by novice surgeons in toy, small and medium breed dogs. Operations with 3D printed PSGs allow novice surgeons to achieve better or similar outcomes in accurate placement of pin/screws in vertebrae.

• Journal of Radiation Protection and Research
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• v.47 no.4
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• pp.214-225
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• 2022

Background: The conventional cerium-doped Gd₂Al₂Ga₃O₁₂ (GAGG(Ce)) scintillator-based gamma-ray imager has a bulky detector, which can lead to incorrect positioning of the gammaray source if the shielding against background radiation is not appropriately designed. In addition, portability is important in complex environments such as inside nuclear power plants, yet existing gamma-ray imager based on a tungsten mask tends to be weighty and therefore difficult to handle. Motivated by the need to develop a system that is not sensitive to background radiation and is portable, we changed the material of the scintillator and the coded aperture. Materials and Methods: The existing GAGG(Ce) was replaced with Bi₄Ge₃O₁₂ (BGO), a scintillator with high gamma-ray detection efficiency but low energy resolution, and replaced the tungsten (W) used in the existing coded aperture with lead (Pb). Each BGO scintillator is pixelated with 144 elements (12 × 12), and each pixel has an area of 4 mm × 4 mm and the scintillator thickness ranges from 5 to 20 mm (5, 10, and 20 mm). A coded aperture consisting of Pb with a thickness of 20 mm was applied to the BGO scintillators of all thicknesses. Results and Discussion: Spectroscopic characterization, imaging performance, and image quality evaluation revealed the 10 mm-thick BGO scintillators enabled the portable gamma-ray imager to deliver optimal performance. Although its performance is slightly inferior to that of existing GAGG(Ce)-based gamma-ray imager, the results confirmed that the manufacturing cost and the system's overall weight can be reduced. Conclusion: Despite the spectral characteristics, imaging system performance, and image quality is slightly lower than that of GAGG(Ce), the results show that BGO scintillators are preferable for gamma-ray imaging systems in terms of cost and ease of deployment, and the proposed design is well worth applying to systems intended for use in areas that do not require high precision.

• Animal Bioscience
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• v.36 no.12
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• pp.1860-1868
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• 2023

Objective: This study was conducted to evaluate the effects of optimal trace mineral levels on the physiological responses, reproductive performance, litter performance, blood profiles and milk composition in gestating sows. Methods: A total of 59 multiparous sows (Yorkshire×Landrace) with similar body weight (BW), backfat thickness (BF), and parity were assigned to one of four treatments with 14 or 15 sows per treatment using a completely randomized design. The treatments were 100% (M1), 300% (M3), 600% (M6), and 900% (M9) of the National Research Council (NRC) Nutrient Requirements of Swine. During lactation period, all the sows were fed the same commercial lactation diet. Results: No significant differences were observed in the BW, BF, reproductive performance, milk composition, or growth performance of the piglets. On day 70 of gestation, the serum zinc concentration showed a quadratic response to M6 treatment (quadratic, p<0.05). Moreover, as the dietary mineral levels increased, the zinc concentration increased linearly at 110 days of gestation (linear, p<0.05). Furthermore, copper and iron concentrations in the serum of sows at 24 h postpartum decreased linearly when high levels of dietary minerals were provided (linear, p<0.05). In the serum of piglets, serum zinc concentrations decreased linearly (linear, p<0.05), and iron concentration showed a quadratic response (quadratic, p<0.05) with an increase in trace mineral premix levels in gestation diets. Conclusion: The current trace mineral requirements of NRC (2012) are suitable for gestating sows, and the addition of dietary mineral levels in the gestating diet did not show any improvements during the gestation and lactation periods.

• Steel and Composite Structures
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• v.51 no.1
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• pp.25-41
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• 2024

The measurement of pile bearing capacity is crucial for the design of pile foundations, where in-situ tests could be costly and time needed. The primary objective of this research was to investigate the potential use of fuzzy-based techniques to anticipate the maximum weight that concrete driven piles might bear. Despite the existence of several suggested designs, there is a scarcity of specialized studies on the exploration of adaptive neuro-fuzzy inference systems (ANFIS) for the estimation of pile bearing capacity. This paper presents the introduction and validation of a novel technique that integrates the fire hawk optimizer (FHO) and equilibrium optimizer (EO) with the ANFIS, referred to as ANFIS_FHO and ANFIS_EO, respectively. A comprehensive compilation of 472 static load test results for driven piles was located within the database. The recommended framework was built, validated, and tested using the training set (70%), validation set (15%), and testing set (15%) of the dataset, accordingly. Moreover, the sensitivity analysis is performed in order to determine the impact of each input on the output. The results show that ANFIS_FHO and ANFIS_EO both have amazing potential for precisely calculating pile bearing capacity. The R² values obtained for ANFIS_FHO were 0.9817, 0.9753, and 0.9823 for the training, validating, and testing phases. The findings of the examination of uncertainty showed that the ANFIS_FHO system had less uncertainty than the ANFIS_EO model. The research found that the ANFIS_FHO model provides a more satisfactory estimation of the bearing capacity of concrete driven piles when considering various performance evaluations and comparing it with existing literature.

• Journal of Life Science
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• v.26 no.5
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• pp.571-583
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• 2016

Biogenic amines are produced primarily by microorganisms found in fermented foods and are often implicated in poisoning incidents in humans. In this study, 620 strains of microorganisms were isolated from traditional Korean fermented food in Sunchang in order to screen for non-biogenicamine-producing microorganisms present in these foods. One strain was identified and named Bacillus subtilis SCJ1, by using 16S rRNA sequencing and biochemical characterization. We investigated the cell growth of this organism in order to understand its potential for industrial application. To this end, we optimized the culture medium constituents by using the response surface methodology. The Plackett-Burman experimental design was used for screening of the medium constituents, such as molasses, yeast extract and peptone, for improving cell growth. In order to determine the optimal concentration of each constituent, we used a central composite design. Consequently, the optimized concentrations of molasses, yeast extract and peptone were predicted to be 27.5 g/l, 7.5 g/l and 17.5 g/l, respectively. By model verification, we confirmed that a 1.49-fold increase in dry cell weight compared to the basal medium-from 1.32 g/l, to 1.9722 g/l-was achieved.