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891.
Su Won Park Soo Jin Lee You Sin Sim Jin Young Choi Eun Young Park Bong Soo Noh 《Food science and biotechnology》2017,26(2):311-317
The purpose of this study was to analyze ethanol content in soy sauce using mass spectrometry (MS) with electronic nose (e-nose) to determine if MS e-nose can replace gas chromatographic analysis for halal certification. Gas chromatography–flame ionization detector (GC-FID), the standard method of ethanol content, was used to analyze 24 different kinds of soy sauce. Ethanol was detected from 13 soy sauce samples in the concentration range of 0.0004–1.7wt%. The MS e-nose data were analyzed by discriminant function analysis (DFA). Based on an addition method, the results were more than 96.6% accurate when the ethanol concentrations were greater than 0.5%. A high correlation between the first score of the DFA plot and the ethanol concentration was observed. Thus, mass spectrometry based on e-nose is an efficient method for determining ethanol as a primary screening tool for halal certification. 相似文献
892.
Yim Sang Ryun Park Ga Young Lee Kwang Won Chung Myung-Sub Shim Soon-Mi 《Food science and biotechnology》2017,26(1):293-298
Food Science and Biotechnology - The objectives of this study was to examine the amount of total arsenic and arsenic speciation in different types of rice from two areas in Korea using inductively... 相似文献
893.
Even though there is great potential to reduce greenhouse gas emissions from existing buildings, most political effort in Korea has been focused on the construction of new buildings; few concrete measures have been taken to limit greenhouse gas emissions from existing buildings. This study examined the potential to reduce greenhouse gas emissions from existing residential buildings as a means to cope with global warming. Additionally, several barriers to improving the energy performance of existing dwellings instead of constructing new dwellings were explored. The major barriers to improving the energy performance of existing residential buildings are: (1) a lack of awareness; (2) financial reasons; (3) insufficient information; and (4) the absence of regulatory systems. To overcome such barriers, systems adopted and implemented in developed European countries were considered and their feasibility was verified so that political measures could be suggested to improve the energy performance of existing dwellings in Korea. 相似文献
894.
Sung-Dae Kim Sang-Hwa Baek Tae-Yeob Kang So-Jin Park Chulju Kim Han Seo Ko 《Journal of Mechanical Science and Technology》2012,26(10):3339-3345
Thermal behaviors of combined weapon systems were analyzed by developed computational programs in this study. Also, temperature distributions of the materials of the system were measured according to the experimental conditions. Field tests that reflected the calculated thermal flow characteristics and the measured temperature distributions of the materials were prepared in a large environmental tester for the weapon systems. Boundary conditions of the analysis were the inlet and outlet conditions of the environmental tester and the low temperature limit of ?32°C. The soaking time of the system, including a fuel tank and a battery in the environmental tester, was obtained by the programs developed in this study to carry out the experiment in the predicted conditions. 相似文献
895.
Robotics‐based telepresence using multi‐modal interaction for individuals with visual impairments
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Chung Hyuk Park Ayanna M. Howard 《International Journal of Adaptive Control and Signal Processing》2014,28(12):1514-1532
Although many assistive devices have been developed and utilized to aid in daily living, the most general assistive means for individuals with visual impairments are the walking cane and guide dogs. These assistive means are effective in assisting the user in navigating within an environment; however, the navigation space is limited to the proximal environment of the user. Thus, in this paper, we discuss a method to increase the range of accessibility to a remote environment through robotic embodiment that enables teleoperation and teleperception through multi‐modal feedback. In order to transform remote spatial information into a non‐visual modality, we present a framework for utilizing an RGB‐D‐based depth camera, a mobile robot, and a haptic interface for 3D haptic rendering to accomplish the goal of haptic exploration of a remote environment. Experiments with three different control methods for robot interaction are designed for users with and without visual impairments. Several hypothesis are built to study the correlation between control/feedback modality and performance in telerobotic operations. Results show that users performed best when combining semi‐autonomous navigation with 3D haptic exploration and also rated their experience with our system as fairly good. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
896.
The manufacture of a marine propeller typically requires long lead-time to generate five-axis tool paths. It usually takes several days to generate satisfactory tool paths with a general purpose CAD/CAM system. This paper proposes a novel methodology that generates effective five-axis tool paths for marine propellers. The machining of a propeller is accomplished in three steps: rough cut, semi-finish cut, and finish cut. For generating accurate finish cut tool paths, the proposed system computes check vectors that determine a maximum range of valid tool motion based upon tool size and passage width for each CL (Cutter Location) point along the tool path. Interference-free tool paths can be acquired by positioning the tool inside the two check vectors. The modelling capability for propellers is also of importance because it determines the eventual success or failure of the whole process. An iterative B-spline surface modelling technique is employed to improve the accuracy of the models and to increase the productivity. The proposed system generates interference-free tool paths with superior surface finish and reduces lead-time to manufacture a propeller. The system validation and sample results are given and discussed. 相似文献
897.
Kwan-Ho Kim Su-Dong Park Jae-Hwan Kim Chul-Min Bae 《Metals and Materials International》2012,18(6):917-921
The fatigue characteristics of bearing steel in ultrasonic fatigue tests are investigated with regard to the role of spheroidized carbides. The results show that, despite a similar hardness level, the bearing steel with spheroidized carbide has a much longer fatigue life than steel without, and that the failure mechanism differs in each case. All the samples of SAQT-processed steel examined using ultrasonic fatigue tests were characterized by a conventional fish-eye structure, which implies they went through subsurface-originated or interior inclusion-induced failure. On the contrary, it was shown that surface-induced failure prevailed in the QT-processed steel without spheroidized carbide. The results suggest spheroidized carbide may strengthen the tempered martensitic matrix of the bearing steel and concentrate the stress around an inclusion rather than at the surface, allowing for prolonged fatigue life over the steel without spheroidized carbide. 相似文献
898.
Young K. Chung Kyung Y. Chang Hoon S. Park Mi‐Hee Kim Kang‐Min Lee Tae‐Seok Lim Hyung W. Kim 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(2):551-555
Carbamazepine (CBZ) intoxication can be associated with severe toxicity, including neurological and cardio‐respiratory abnormalities. Highly protein‐bound, CBZ is not removed efficiently through conventional hemodialysis. Charcoal hemoperfusion is the most effective extracorporeal elimination therapy for CBZ intoxication. Recent reports have indicated that continuous venovenous hemodiafiltration (CVVHDF), albumin‐enhanced continuous venovenous hemodialysis, high‐flux hemodialysis and plasma exchange can be as effective as charcoal hemoperfusion. In contrast to recent reports, which demonstrated the effectiveness of CVVHDF with high dialysate flow in CBZ intoxication, we observed that serum CBZ level was decreased minimally by albumin‐enhanced CVVHDF with low dialysate flow. Therefore, albumin‐enhanced CVVHDF with high dialysate flow should be considered in severe CBZ intoxication, if hemoperfusion is unavailable because of the lack of facilities or if it cannot be performed. 相似文献
899.
To evaluate the microbiological safety of Korean traditional seasoned beef processed by sous-vide method, Clostridium perfringens spores were inoculated into the samples, and then germination and growth of spores were observed under different temperatures for days. Also, changes in pH, water activity, and salt contents were analyzed. As the results, there was no difference in water activity and pH of the samples during the storage at any temperature. However, salt contents of the samples significantly increased as storage time increased, and the storage temperature affected the change of salt contents. C. perfringens did not grow at 4 and 10°C for 24 days however, the bacterial growth was observed at 20°C after 2 days of storage. Based on these simulation tests, the microbiological safety of sous-vide processed galbijjim can be guaranteed at 4 and 10°C for 24 days even though the raw materials were contaminated by C. perfringens spores. 相似文献
900.