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81.
Effects of yuja peel extract and its flavanones on osteopenia in ovariectomized rats and osteoblast differentiation 下载免费PDF全文
82.
Hyun-Moo Hur Joon-Hyuk Park Won-Hee You Tae-Won Park 《Journal of Mechanical Science and Technology》2009,23(10):2790-2800
A study was conducted to analyze the influence of wheel profile wear on running stability by using a 1/5 scale bogie model.
The critical speed was analyzed by constructing a dynamic model for the bogie model. And the 1/5 scale bogie and a scaled
roller rig prototype were manufactured to verify the feasibility of applying the scale model; a critical speed test was conducted
for worn wheel profile samples. The test results for the scale model were consistent with the simulation results for the scale
model within the range of 5% or less. Also, the variation of the critical speed of the scale model for the wheel profile wear
shows a similar trend with the analysis results of the full scale model. Therefore, using the scale model to analyze the influence
of wheel profile wear on running stability shows sufficient feasibility as a model to analyze the stability of a full scale
bogie. 相似文献
83.
Yeung Joon Choi Sungik Hur Byeong-Dae Choi Kunihiko Konno Jae W. Park 《Journal of food science》2009,74(1):C17-C24
ABSTRACT: Fish protein isolate were recovered from frozen small croaker using pH shift. The partial enzymatic hydrolysates were fractionated as soluble and insoluble parts. They were dried using the drum dryer and their functional properties were examined. The total nitrogen content of the enzymatic hydrolysates ranged from 12.9% to 13.7%. The degree of hydrolysis of precipitates was 18.2% and 12.2% for croaker hydrolysates treated with Protamex 1.5 MG ( Bacilllus protease complex) and Flavourzyme 500 MG (endoproteases and exoproteases, Aspergillus oryzae ), respectively. The TCA supernatant, after centrifugation of hydrolysates, contained numerous peptides ranging from 100 to 4000 daltons. The solubility of the supernatants was higher than that of the precipitates at 0% to 3% NaCl and pH 2 to 10. The precipitate of Flavourzyme- and Protamex-treated hydrolysates showed a high emulsion activity index value compared to egg white and bovine plasma protein. In addition, the highest emulsion stability was observed for Protamex-treated precipitate hydrolysates. Emulsion stability of Protamex-treated precipitate hydrolysates was comparable to those of protein additives (egg white, bovine plasma protein, and soy protein concentrate). Water and fat binding capacity of precipitates were higher than those of supernatant. The results indicate that precipitate hydrolysate from undersized croaker can be used in processed muscle foods as a functional and nutritional ingredient. 相似文献
84.
Hong-Kee Lee Jun-Mi Jeon Min Hyung Lee Ho-Nyun Lee Jin-Young Hur 《Metals and Materials International》2013,19(1):119-122
The characteristics of electroless NiCoP films were investigated as a function of Co content. Sheet resistance of a multi-stacked film of SiO2/Ta/Cu/NiP dramatically increased after annealing at 500 °C, but as more Co was co-plated in NiCoP film, the change in sheet resistance of the stacked film of SiO2/Ta/Cu/NiCoP at 500 °C became smaller. A CoP/Cu film showed no change in resistance value after annealing, which indicates the CoP film is the most effective Cu diffusion barrier. X-ray diffraction analysis showed that an as-plated NiP film of amorphous structure is easily crystallized by thermal annealing over 300 °C, while CoP showed an insignificant change in crystal structure by thermal annealing up to 500 °C. This result reveals that the CoP film is capable of preventing the diffusion of Cu at 500 °C due to the thermal stability of CoP film. 相似文献
85.
WDFTC is a wavelet-based distribution-free CUSUM chart for detecting shifts in the mean of a profile with noisy components. Exploiting a discrete wavelet transform (DWT) of the mean in-control profile, WDFTC selects a reduced-dimension vector of the associated DWT components from which the mean in-control profile can be approximated with minimal weighted relative reconstruction error. Based on randomly sampled Phase I (in-control) profiles, the covariance matrix of the corresponding reduced-dimension DWT vectors is estimated using a matrix-regularisation method; then the DWT vectors are aggregated (batched) so that the non-overlapping batch means of the reduced-dimension DWT vectors have manageable covariances. To monitor shifts in the mean profile during Phase II operation, WDFTC computes a Hotelling's T 2-type statistic from successive non-overlapping batch means and applies a CUSUM procedure to those statistics, where the associated control limits are evaluated analytically from the Phase I data. Experimentation with several normal and non-normal test processes revealed that WDFTC was competitive with existing profile-monitoring schemes. 相似文献
86.
Shuaiyu Wang Yeo Cho Yoon Mi-Jeong Sung Jin-Taek Hwang Haeng-Jeon Hur Hyun-Jin Kim Hye Jeong Yang Myung-Sunny Kim Dae Young Kwon Jae-Ho Park 《Journal of Functional Foods》2012,4(4):899-905
Auraptene is a citrus-derived natural monoterpene that has been shown to exert anti-cancer, anti-bacterial, anti-inflammatory, and antioxidant roles. Since little is known about other biological functions of auraptene, we examined the efficacy of auraptene for stimulating angiogenesis in human umbilical vein endothelial cells (HUVECs). Treatment with low concentrations of auraptene stimulated endothelial cell proliferation, migration, and tube formation. Furthermore, auraptene activated Erk, Akt, and endothelial nitric oxide synthase (eNOS), and increased NO production. Auraptene also partially induced the phosphorylation of VEGFR2. Furthermore, auraptene-induced activation of Erk, Akt, and eNOS were significantly inhibited by the inhibitors PD98059, LY294002, and l-NIO dihydrochloride. These results suggest that auraptene stimulates angiogenesis by regulating the VEGFR2, Erk, and PI3K/Akt-eNOS signaling pathways. 相似文献
87.
Woo-Yong Lee Kyeong Hur Kwang-il Hwang Doo-Seop Eom Jong-Ok Kim 《Wireless Personal Communications》2012,62(2):257-275
In this paper, algorithms for navigating a mobile robot through wireless sensor networks are presented. The mobile robot can
navigate without the need for a map, compass, or GPS module while interacting with neighboring sensor nodes. Two navigation
algorithms are proposed in this paper: the first uses the distance between the mobile robot and each sensor node and the second
uses the metric calculated from one-hop neighbors’ hop-counts. Periodically measuring the distance or metric, the mobile robot
can move toward a point where these values become smaller and finally come to reach the destination. These algorithms do not
attempt to localize the mobile robot for navigation, therefore our approach permits cost-effective robot navigation while
overcoming the limitations of traditional navigation algorithms. Through a number of experiments and simulations, the performance
of the two proposed algorithms is evaluated. 相似文献
88.
Woo-Yong Lee Kyeong Hur Taeyoung Kim Doo-Seop Eom Jong-Ok Kim 《Wireless Personal Communications》2012,63(1):241-260
The task of formulating an efficient system for determining the location of an object, results in the creation of a wide number
of applications and services. For this reason, most wireless sensor network applications assume the availability of sensor
location information. In this paper, an indoor localization scheme, which is based on synchronized sensor nodes, is proposed.
It is efficient in terms of power consumption and location update rate. Furthermore, it resolves the scalability problem usually
found in most conventional indoor localization systems in large scale indoor environments. The performance of the proposed
scheme is evaluated through experimental implementation and is compared with the Cricket system. The results demonstrate that
the proposed scheme is a promising and feasible localization system for a large scale indoor environment. 相似文献
89.
Chang Ho Jeong Young Il Bae Soo Jeong Park Si Kyung Lee Sun Jin Hur 《Food science and biotechnology》2012,21(6):1557-1563
In order to obtain basic data required for utilization of guava leaf as a functional substance, the antioxidant activities of aqueous extracts from 3 cultivars of guava leaf (‘Apple color’, ‘Ruby’, and ‘Safeda’) were examined. The total phenolic contents of the aqueous extracts ranged from 257.38 to 293.25 mg/g gallic acid equivalents. DPPH, ABTS, reducing power, ferric reducing antioxidant power (FRAP), ferric thiocyanate (FTC), and malondialdehyde (MDA) assays indicated that the aqueous extract of the ‘Ruby’ cultivar was the most potent radicalscavenger and reducing agent compared to the other 2 cultivars. Therefore, this study verified that aqueous extract from the ‘Ruby’ cultivar possessed strong antioxidant activity that correlated to its high level of phenolics, particularly gallic acid. In conclusion, the aqueous extract of the ‘Ruby’ cultivar of guava leaf may be utilized as an effective source of functional food materials, including natural antioxidants. 相似文献
90.
Multicast is a scalable solution for group communications. In order to offer security for multicast applications, a group
key has to be changed whenever a member joins or leaves the group. This incurs 1-affects-n problem, which is a constraint on scalability. Decentralized approaches solve the scalability problem by dividing a group
into several subgroups that use independent group keys. These approaches, however, introduce new challenges: problem of trusting
third party and inefficiency of data delivery. Proxy encryption is a good approach to solve the problem of trusting third
party. In this paper, we propose a novel secure multicast scheme using the proxy cryptography. The proposed scheme provides
not only scalability but also data transmission efficiency by dynamic subgrouping of group members while intermediate data-relaying
third parties are not required to be trusted. 相似文献