• Journal of Power Electronics
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• 제14권6호
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• pp.1243-1253
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• 2014

The phase inductance of a switch reluctance motor (SRM) is significantly nonlinear. With different saturation conditions, the phase inductance shape is clearly changed. This study focuses on the relationship between coefficient and current in an inductance model with ignored harmonics above the order of 3. A position estimation method based on the variable coefficient inductance model is proposed in this paper. A four-quadrant sensorless control system of the SRM drive is constructed based on the relationship between variable coefficient inductance and rotor position. The proposed algorithms are implemented in an experimental SRM test setup. Experimental results show that the proposed method estimates position accurately in operating two/four-quadrants. The entire system also has good static and dynamic performance.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 The 8th Asian Symposium on Precision Forging ASPF
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• pp.133-137
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• 2003

In this paper presented the net forging technology of planetary gear after much experiment and analysis, technology of two forging processes after billet being one -time heated, and cold net forging was adopted to ensure the gear forming quality. In the process of die producing, electrical rod NC cutting technology was used .the test and application has proved the net forging gear has reached higher quality and met the requirement of design. The net forging gear technology had been put into production.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권5호
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• pp.2003-2021
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• 2020

Today's computer systems are widely integrated with CPU and GPU to achieve considerable performance, but energy consumption of such system directly affects operational cost, maintainability and environmental problem, which has been aroused wide concern by researchers, computer architects, and developers. To cope with energy problem, we propose a task-scheduling framework to reduce energy under performance constraint by rationally allocating the tasks across the CPU and GPU. The framework first collects the estimated energy consumption of programs and performance information. Next, we use above information to formalize the scheduling problem as the 0-1 knapsack problem. Then, we elaborate our experiment on typical platform to verify proposed scheduling framework. The experimental results show that our proposed algorithm saves 14.97% energy compared with that of the time-oriented policy and yields 37.23% performance improvement than that of energy-oriented scheme on average.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1589-1593
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• 2012

Objective: To investigate liver fibrosis, TGF-${\beta}1$ levels and curative effects on hepatocellular carcinoma (HCC) with small and conventional dose perfusion chemotherapy by transcatheter arterial chemo embolization (TACE). Methods: Thirty-six hepatocellular carcinoma patients not indicated for surgical resection underwent super-selective transcatheter arterial chemoembolization, divided into small dose (n=15) and conventional dose (n=21) chemotherapy groups. Results: With conventional doses, four indices of liver fibrosis focusing on hyaluronate acide (HA), human procollagen type-III (hPC-III), collagen type-Ⅳ (Ⅳ-C) and transforming growth factor-${\beta}l$ (TGF-${\beta}1$) were obviously increased postoperative compared with preoperative (P<0.01); in contrast, with small doses there were no significant differences except for TGF-${\beta}1$. Five year survival demonstrated no significant differences between the two groups (P>0.05). Conclusion: To hepatocellular carcinoma patients treated by TACE, reducing doses of chemotherapy drugs can reduce progress of liver fibrosis, without impacting on five year survival.

• Journal of Power Electronics
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• 제13권4호
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• pp.719-728
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• 2013

A novel hybrid active power filter (NHAPF) that can be adopted in high-voltage systems is proposed in this paper. The topological structure and filtering principle of the compensating system is provided and analyzed, respectively. Different controlling strategies are also presented to select the suitable strategy for the compensation system. Based on the selected strategy, the harmonic suppression function is used to analyze the influence of system parameters on the compensating system with MATLAB. Moreover, parameters in the injection branch are designed and analyzed. The performance of the proposed NHAPF in harmonic suppression and reactive power compensation is simulated with PSim. Thereafter, the overall control method is proposed. Simulation analysis and real experiments show that the proposed NHAPF exhibits good harmonic suppression and reactive power compensation. The proposed compensated system is based on the three-phase four-switch inverter, which is inexpensive, and the control method is verified for validity and effectiveness.

• 지질공학
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• 제25권3호
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• pp.323-329
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• 2015

Shale gas reserves in China are large, although shale gas production is still in its infancy. This paper reviews Chinese national policies and guidelines related to shale gas development, in particular those related to recent progress in the development of shale gas reserves in Sichuan Province and Chongqing since February 2015. In addition, three large-scale R&D projects related to shale gas development, funded by the Government of China, are introduced, and the scope of the work in each project is described.

• Journal of Ginseng Research
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• 제38권4호
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• pp.227-232
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• 2014

Jilin Province is one of the principal production bases of traditional Chinese medicine (TCM) in China with its typical preponderance in TCM resources, research and development power, and industrialization capacity. The province has 2,790 species of TCM materials in total. Over 20% of the TCM materials in common use are from Jilin Province. The province has established 36 good agricultural practice bases for 22 typical TCMs. The overall situation, in terms of collection, processing, and preparation, and the implementation of good agricultural practice of TCM materials in Jilin Province are summarized.

• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.246-248
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• 2013

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.272-273
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• 2006

A new process of pulsed electric current sintering was developed. It combines compaction with activated sintering effectively and can manufacture bulky nano-crystalline materials very quickly. A nano-structured steel is obtained with high relative density and hardness by this process. The average grain size of iron matrix is 58nm and the carbide particulate size is less than 100 nm. The densification temperature of ball-milled powders is approximately $200^{\circ}C$ lower than that of blended powders. When the sintering temperature increases, the density of as-sintered specimen increases but the hardness of as-sintered specimen first increases and then decreases.

• Nuclear Engineering and Technology
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• 제51권3호
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• pp.769-775
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• 2019

The tensile strength of irradiated 3C-SiC, SiC with artificial point defects, SiC with symmetric tilt grain boundaries (GBs), irradiated SiC with GBs are investigated using molecular dynamics simulations at 300 K. For an irradiated SiC sample, the tensile strength decreases with the increase of irradiation dose. The Young's modulus decreases with the increase of irradiation dose which agrees well with experiment and simulation data. For artificial point defects, the designed point defects dramatically decrease the tensile strength of SiC at low concentration. Among the point defects studied in this work, the vacancies drop the strength the most seriously. SiC symmetric tilt GBs decrease the tensile strength of pure SiC. Under irradiated condition, the tensile strengths of all SiC samples with grain boundaries decrease and converge to certain value because the structures become amorphous and the grain boundaries disappear after high dose irradiation.