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41.
Relationship of Carcass Weight to Muscle Fiber Characteristics and Pork Quality of Crossbred (Korean Native Black Pig × Landrace) F2 Pigs 总被引:1,自引:0,他引:1
Gap-Don Kim Byeong-Woo Kim Jin-Yeon Jeong Sun-Jin Hur In-Chul Cho Hyun-Tae Lim Seon-Tea Joo 《Food and Bioprocess Technology》2013,6(2):522-529
A total of 168 carcasses of crossbred (Korean native black pig × Landrace) F2 pigs were divided into four carcass weight groups (A, 70–79 kg; B, 80–89 kg; C, 90–99 kg; D, 100–109 kg). The influence of carcass weight on muscle fiber characteristics and meat quality traits of pork, from the longissimus dorsi, were investigated. Carcass traits such as loin-eye area and back-fat thickness were found to increase with increasing carcass weight. Fat content, sarcomere length, drip loss, and meat color values (L*, a*, and b*) also increased with increasing carcass weight. However, moisture content and Warner–Bratzler shear force decreased with increasing carcass weight. A decrease in the compositions of type I and IIA fibers and an increase in the composition of type IIB fibers were observed with increasing carcass weight. The heavier carcasses showed type I and IIB fibers of bigger size and a smaller size of type IIA fibers. Fiber number percentage and the diameter of type IIB showed a significant positive correlation with carcass weight, fat content, and lightness (p?<?0.05). Fiber diameter of type IIB was positively correlated with loin-eye area, but was negatively correlated with moisture content. However, muscle fiber characteristics had no correlation with back-fat thickness, ultimate pH, Warner–Bratzler shear force, and b* value. In conclusion, crossbred pig which has of high composition and size of type IIB has high lightness (L* value) and water-holding capacity (drip loss). Therefore, excessively high weight of carcass has influence on pale and exudative properties in pig because of muscle fiber characteristics, especially type IIB fiber. 相似文献
42.
Do Haeng Hur Myung Sik Choi Uh Chul Kim Jung Ho Han 《Nuclear Engineering and Design》2003,220(1):916-16
The effect of temperature on magnetite dissolution and corrosion behavior was evaluated in ethylenediaminetetraacetic acid (EDTA)-based solvents for iron oxide chemical cleaning of nuclear steam generators at temperatures ranging from 93 to 150 °C. Magnetite dissolution was drastically accelerated as the temperature was raised to 150 °C, while the amount of corrosion was controlled well within an allowable limit. Periodic venting and excessive EDTA concentration in the solvents were expected to be very effective in dissolving hard tube sheet sludge piles. The linear polarization (LP) method was also suitable to monitor the changes of corrosion rates and process conditions such as venting. 相似文献
43.
Laparoscopically assisted vaginal hysterectomy 总被引:1,自引:0,他引:1
OBJECTIVE: To report our experience with laparoscopically assisted vaginal hysterectomy (LAVH) and evaluate the advantages of LAVH. STUDY DESIGN: From January 1991 to August 1992, 176 LAVHs were performed at the Department of Obstetrics and Gynecology, College of Medicine, Chung-Ang University, Seoul, Korea. The indications for LAVH, based on the preoperative diagnosis, were uterine myomas, dysmenorrhea, chronic pelvic inflammatory disease or pelvic pain, dysfunctional uterine bleeding and cervical intraepithelial neoplasia (in order of frequency). RESULTS: Patients had concomitant procedures, including incidental appendectomy, posterior wall repair, pelvic adhesiolysis and salpingo-oophorectomy. Bipolar forceps were used to compress and desiccate vessels. The Nd-YAG laser, scissors and/or unipolar electrode were used for tissue division, excision of adhesions and cutting. The intraoperative complications were bladder perforation, massive hemorrhage and inferior epigastric vessel injury (one case each). The postoperative complications were infection, voiding difficulty, febrile morbidity, pelvic abscess, incisional hernia, vaginal vault bleeding and peroneal nerve palsy (one case each). CONCLUSION: Hysterectomy can be safely performed vaginally assisted by operative laparoscopy by well-trained laparoscopists, resulting in reduced surgical morbidity, blood loss, postoperative discomfort, recovery time and hospitalization. 相似文献
44.
Characteristic Analysis of Interior Permanent-Magnet Synchronous Motor in Electrohydraulic Power Steering Systems 总被引:1,自引:0,他引:1
Jin Hur 《Industrial Electronics, IEEE Transactions on》2008,55(6):2316-2323
This paper presents design and analysis results of a 2.6-kW interior permanent-magnet synchronous motor developed for an electrohydraulic power steering system. The motor was designed by using the proposed equivalent magnetic circuit model in consideration with a core loss. To analyze motor characteristics by using the equivalent magnetic circuit model, inductance and iron-loss resistance, which are affected critically by magnetic saturation, are obtained by using finite-element analysis. Finally, motor characteristics such as armature current, torque, and efficiency are calculated by the equivalent magnetic circuit model and verified by experimental results. 相似文献
45.
A. Vapirev J. Deca G. Lapenta S. Markidis I. Hur J.‐L. Cambier 《Concurrency and Computation》2015,27(3):581-593
We present initial comparison performance results for Intel many integrated core (MIC), Sandy Bridge (SB), and graphical processing unit (GPU). A 1D explicit electrostatic particle‐in‐cell code is used to simulate a two‐stream instability in plasma. We compare the computation times for various number of cores/threads and compiler options. The parallelization is implemented via OpenMP with a maximum thread number of 128. Parallelization and vectorization on the GPU is achieved with modifying the code syntax for compatibility with CUDA. We assess the speedup due to various auto‐vectorization and optimization level compiler options. Our results show that the MIC is several times slower than SB for a single thread, and it becomes faster than SB when the number of cores increases with vectorization switched on. The compute times for the GPU are consistently about six to seven times faster than the ones for MIC. Compared with SB, the GPU is about two times faster for a single thread and about an order of magnitude faster for 128 threads. The net speedup, however, for MIC and GPU are almost the same. An initial attempt to offload parts of the code to the MIC coprocessor shows that there is an optimal number of threads where the speedup reaches a maximum. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
46.
Un Jeong Kim Sun Il Kim Sungwoo Hwang Jaehyun Hur 《Journal of Materials Science》2014,49(24):8328-8334
We present a novel method for fabricating two-dimensional arrays of zinc oxide (ZnO) nanorod patterns. Vertically aligned ZnO nanostructure patterns were synthesized by hydrothermal growth on a two-dimensional seed layer pattern formed by atomic layer deposition. Various characteristics of ZnO seed films were experimentally studied in order to optimize the fabrication of ZnO rod structures in terms of their uniformity and vertical alignment on the two-dimensional-patterned surfaces. Using these ZnO structures as hierarchical electrodes, we demonstrate that localized electric fields in the proximity of ZnO rod patterns can be used for periodic alignment of liquid crystal molecules, resulting in the optical diffraction grating effect. Process conditions for creating ZnO rod patterns that best enhance diffraction efficiency are further discussed. The current study is the first demonstration of hierarchical ZnO rod patterns as electrodes for optical modulation of a medium. We believe this will be beneficial for future optical applications. 相似文献
47.
Junbeom Hur 《Wireless Networks》2011,17(5):1235-1249
Distributed sensor networks are becoming a robust solution that allows users to directly access data generated by individual
sensors. In many practical scenarios, fine-grained access control is a pivotal security requirement to enhance usability and
protect sensitive sensor information from unauthorized access. Recently, there have been proposed many schemes to adapt public
key cryptosystems into sensor systems consisting of high-end sensor nodes in order to enforce security policy efficiently.
However, the drawback of these approaches is that the complexity of computation increases linear to the expressiveness of
the access policy. Key-policy attribute-based encryption is a promising cryptographic solution to enforce fine-grained access
policies on the sensor data. However, the problem of applying it to distributed sensor networks introduces several challenges
with regard to the attribute and user revocation. In this paper, we propose an access control scheme using KP-ABE with efficient
attribute and user revocation capability for distributed sensor networks that are composed of high-end sensor devices. They
can be achieved by the proxy encryption mechanism which takes advantage of attribute-based encryption and selective group
key distribution. The analysis results indicate that the proposed scheme achieves efficient user access control while requiring
the same computation overhead at each sensor as the previous schemes. 相似文献
48.
Characterization of spectral responses of humic substances upon UV irradiation using two-dimensional correlation spectroscopy 总被引:1,自引:0,他引:1
The spectral responses of a leaf litter derived humic substance (LLHS) and Suwannee River fulvic acid (SRFA) upon ultraviolet (UV) A irradiation were characterized using two-dimensional correlation spectroscopy (2D-COS) based on the absorption and the synchronous fluorescence spectra at different irradiation times. A 12 day irradiation on the humic substances (HS) resulted in higher reduction of the absorbance relative to the dissolved organic carbon concentration, suggesting that aromatic chromophores were preferentially oxidized and/or non UV-absorbing compounds were generated by the photobleaching. Synchronous fluorescence spectra revealed the preferential removal of fulvic-like and humic-like fluorophores and delayed response of protein-like fluorescence upon the irradiation. The spectral features at long wavelengths (>430 nm) appear to be affected by intra-molecular interactions of the individual chromophores associated with shorter wavelengths. Absorption-based 2D-COS demonstrated that there are three types of absorption bands for the two HS, which changed sequentially in the order of 290-400 nm → 200-250 nm → 250-290 nm. In addition, two or three distinctive fluorescence bands in response to the irradiation were identified from 2D-COS. The sequential orders and the associated wavelength bands were possibly explained by the irradiation wavelengths and the differences between direct and indirect photochemical reactions. The interpretation of the 2D-COS results was very consistent with the kinetic rate constants individually calculated at several discrete wavelengths. Our study demonstrated that 2D-COS could be used as a powerful tool in identifying distinctive bands of HS that have dissimilar behavior and the associated sequential orders by visualizing the spectral changes at continuous wavelengths. 相似文献
49.
Three‐Dimensional Branched Nanowire Heterostructures as Efficient Light‐Extraction Layer in Light‐Emitting Diodes
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Byeong Uk Ye Buem Joon Kim Joonmo Park Hu Young Jeong Jae Yong Park Jong Kyu Kim Jin‐Hoe Hur Myung Hwa Kim Jong‐Lam Lee Jeong Min Baik 《Advanced functional materials》2014,24(22):3384-3391
A facile method to fabricate three‐dimensional branched ZnO/MgO nanowire heterostructures and their application as the efficient light‐extraction layer in light‐emitting diodes are reported. The branched MgO nanowires are produced on the hydrothermally‐grown ZnO nanowires with a small tapering angle towards the tip (≈6°), by the oblique angle flux incidence of MgO. The structural evolution during the growth verifies the formation of the MgO nanoscale islands with strong (111) preferred orientation on very thin (5–7 nm) MgO (110) layer. The MgO nanobranches, then grown on the islands, are polycrystalline consisting of many grains oriented in specific directions of <200> and <220>, supported by the nucleation theory. The LEDs with the branched ZnO/MgO nanowire arrays show a remarkable enhancement in the light output power by 21% compared with that of LEDs with pristine ZnO nanowires. Theoretical calculations using a finite‐difference time‐domain method reveal that the nanostructure is very effective in breaking the wave‐guiding mode inside the ZnO nanowires, extracting more light especially in radial direction through the MgO nanobranches. 相似文献
50.
A case study on detection and sizing of defects in steam generator tubes using eddy current testing 总被引:1,自引:0,他引:1
Eddy current testing (ECT) method is widely used to detect various types of defects occurring in nuclear steam generator tubes. Therefore, the reliability of its detection and sizing accuracy for defects should be validated. For this purpose, two tubes with defect signals were pulled from an operating steam generator and destructively examined. The defect type was a circumferential crack for one tube and an intergranular attack (IGA) for the other tube. The plus point coil probe showed a better capability to detect and size both a circumferential crack and a volumetric IGA than pancake and bobbin coil probe. The destructive results are correlated with the ECT results obtained during the in-service inspection. 相似文献