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871.
Sagar Kafle Ranjan Parajuli Seung Hee Euh Kwang Cheol Oh Yun Sung Choi Kshitij Adhikari 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(1):149-153
Nepal, a country rich in biomass, still does not have any commercial pellet production plants and is wasting large amounts of agricultural crop residue. The current study showed that about 5.61 million tonnes (Mt) of biomass in the form of pellets are potentially available from agricultural crop residues. The brick and cement industries could use these agro-pellets. Co-firing of pellets in such industries could play an important role in reducing the import volume of coal and minimize the related environmental loadings. 相似文献
872.
Choi Jae-Suk Park Sun-Mee Kim Young Hun Oh Sang Cheol Lim Eun Seo Hong Yong-Ki Kim Mi-Ryung 《Food science and biotechnology》2016,25(5):1469-1476
Food Science and Biotechnology - This survey was performed to estimate the levels of pathogenic microorganisms, antibiotic residues, and heavy metals in seven Korean freshwater aquaculture species... 相似文献
873.
Park Soo-Yun Lee So Young Yang Jung Wook Lee Joon-Seol Oh Sung-Dug Oh Seonwoo Lee Si Myung Lim Myung-Ho Park Soon Ki Jang Jae-Seon Cho Hyun Suk Yeo Yunsoo 《Food science and biotechnology》2016,25(1):283-291
Food Science and Biotechnology - We determined the phytochemical diversity, including carotenoids, flavonoids, anthocyanins, and phenolic acids, in sweet potatoes (Ipomoea batatas L.) with... 相似文献
874.
Jang Jin Ho Seo Ji Yeon Oh Jisun Kim Jae-Sik Kim Eun-Jeong Kim Jong-Sang 《Food science and biotechnology》2016,25(3):905-909
Food Science and Biotechnology - In this study, we attempted to develop fruit-based functional juice with anti-inflammatory activity for consumers living under heavy air pollution. At first, four... 相似文献
875.
M. alba L. is a valuable nutraceutical plant rich in potential bioactive compounds with promising anti-gouty arthritis. Here, we have explored bioactives, signaling pathways, and key proteins underlying the anti-gout activity of M. alba L. leaves for the first-time utilizing network pharmacology. Bioactives in M. alba L. leaves were detected through GC-MS (Gas Chromatography-Mass Spectrum) analysis and filtered by Lipinski’s rule. Target proteins connected to the filtered compounds and gout were selected from public databases. The overlapping target proteins between bioactives-interacted target proteins and gout-targeted proteins were identified using a Venn diagram. Bioactives-Proteins interactive networking for gout was analyzed to identify potential ligand-target and visualized the rich factor on the R package via the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway on STRING. Finally, a molecular docking test (MDT) between bioactives and target proteins was analyzed via AutoDock Vina. Gene Set Enrichment Analysis (GSEA) demonstrated that mechanisms of M. alba L. leaves against gout were connected to 17 signaling pathways on 26 compounds. AKT1 (AKT Serine/Threonine Kinase 1), γ-Tocopherol, and RAS signaling pathway were selected as a hub target, a key bioactive, and a hub signaling pathway, respectively. Furthermore, three main compounds (γ-Tocopherol, 4-Dehydroxy-N-(4,5-methylenedioxy-2-nitrobenzylidene) tyramine, and Lanosterol acetate) and three key target proteins—AKT1, PRKCA, and PLA2G2A associated with the RAS signaling pathway were noted for their highest affinity on MDT. The identified three key bioactives in M. alba L. leaves might contribute to recovering gouty condition by inactivating the RAS signaling pathway. 相似文献
876.
Jin-Heon Oh Hae-Eun Jung Jong-sub Lee Kee-Joe Lim Hyun-Hoo Kim Boo-Hyung Ryu Dae-Hee Park 《Journal of Electroceramics》2009,22(1-3):150-155
We propose an ultrasonic motor of high torque with a new configuration for application in automobiles. The newly designed stator is a two sided vibrator consisting of a toothed metal disk with a piezoelectric ceramic ring bonded on both faces of the disk which generates a flexural traveling wave along the circumference of disk. In this configuration, the displacement on the surface of stator may not be confined. It also produces a large vibrating force and amplitude because the vibrator is sandwiched by two piezoelectric plates. It is possible to increase the torque by improving the vibration characteristics. We used the finite element method to compute the vibration mode of the motor of diameter 48 mm. A sixth mode was chosen as the operation mode with a resonance frequency of about 73 kHz. We fabricated a prototype according to this design and measured its performance. The performance measurement of the prototype motor showed that its stall torque was about 1.8 Nm and efficiency was 37% at 60% of the maximum torque. Compared to a conventional motor which employed a single sided piezoelectric vibrator of the same outer diameter, we obtained, with this prototype, a maximum torque of about twice as great. The motor may be useful to apply as an actuator in a mobile car. 相似文献
877.
Yong-Joon Choi Min-Cheol Lee 《International Journal of Precision Engineering and Manufacturing》2009,10(2):53-61
The objective of this study is to develop a coiling process simulator that can be used to test suggested coiling control algorithms,
and thereby improve overall coiling performance. To accomplish this, a thorough study of the pinching and coiling mechanism
of the downcoiler has been carried out, and then used to derive an appropriate mathematical model. An additional torque compensation
algorithm is proposed to improve the shape of the strip to be coiled. The simulation environment permits the coiling process
to be estimated offline, using the actual system parameters necessary for successful coiling. These parameters include strip
tension, pinch roll force, and driving motor power for pinching and coiling. For effective coiling control, the additional
compensated torque algorithm can be used to reduce the irregular shape of the loose coil that sometimes arises from insufficient
coiling torque. In order to evaluate the performance and practicality of both the developed software and the proposed coiling
control algorithm, experiments were conducted using the downcoiler in the No. 2 Hot Strip Mill at Pohang Works, where coiling
operations are normally carried out at high strip tension compared to other downcoilers. The simulations and experimental
results show that the set-up value for the unit tension can actually be lowered, which could lead to significant improvement
in coiling strip quality, as well as reduced power consumption. In addition, a test coiling operation with the additional
torque compensation algorithm resulted in even more effective coiling and a reduction in bad telescope quality of the coiled
strip. 相似文献
878.
Young-Sam Ham Dong-Hyong Lee Seok-Jin Kwon Won-Hee You Taek-Yul Oh 《International Journal of Precision Engineering and Manufacturing》2009,10(1):35-39
Oscillatory wheel load fluctuation of considerable amplitude is always observed in railway cars traveling at high speed. This
paper describes a continuous method for measuring the derailment coefficient and the forces between the wheel and rail. The
acceleration measured on the axle box indicates that the frequency of this fluctuation can be as high as 70 Hz. Continuous
measurement of wheel load using conventional methods is not possible due to this high frequency phenomenon. We have developed
a new method for continuous measurement of these forces and the derailment coefficient using two pairs of strain gauge bridges
with output phases shifted by 90°, and summing their outputs with a weighting function. This method works for measuring the
forces between wheel and rail at high frequencies. 相似文献
879.
880.
It is critical to facilitate business partners to be seamlessly interoperable with each other as the network-centric manufacturing (NCM) paradigm becomes a major trend in today's manufacturing environment. In this work, we propose a semantic e-Kanban inventory system where a semantic gateway is acting as a mapping hub to enable heterogeneous messages to be seamlessly exchanged between business partners on demand. The semantic gateway uses reasoning rules to map business partners’ proprietary data schemas and provides interoperability required for NCM. To observe the network dynamics of our proposed system, a discrete time dynamic model is built and shows its growth to a scale-free network with a convergence rate depending on the initial connectivity of the semantic gateway and preferential attachment parameters. To analyse the proposed system from an economic perspective, analytical and numerical studies are conducted showing that it has enough potential to reduce supply chain costs in comparison to those of the traditional approach. Finally, this study attempts to address the cost-sharing issue encountered when multiple partners are direct beneficiaries of the efficiency gain through a joint network-centric capability, but it is questionable who should pay for the capability implementation. The cost-sharing issue must be investigated because most network-centric capabilities would not be economically or technically feasible for an individual company to achieve. 相似文献