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      • KCI등재

        SINGLE-MACHINE SCHEDULING PROBLEMS WITH AN AGING EFFECT

        Zhao, Chuan-Li,Tang, Heng-Yong 한국전산응용수학회 2007 Journal of applied mathematics & informatics Vol.25 No.1

        This paper considers single machine scheduling problems where the processing time of a job increases as a function of its position in the sequence. In this model, the later a given job is scheduled in the sequence, the longer its processing time. It is shown that the optimal schedule may be very different from that of the classical version of the problem. We introduce polynomial solutions for the makespan minimization problem, the sum of completion times minimization problem and the sum of earliness penalties minimization problem. For two resource constrained problems, based on the analysis of the problems, the optimal resource allocation methods are presented, respectively.

      • KCI등재

        Stochastic single machine scheduling with weighted quadratic early-tardy penalties

        Chuan-li Zhao,Heng-yong Tang 한국전산응용수학회 2008 Journal of applied mathematics & informatics Vol.26 No.5

        The problem of scheduling n jobs on a single machine is considered when the machine is subject to stochastic breakdowns. The objective is to minimize the weighted squared deviation of job completion times from a common due date. Two versions of the problem are addressed. In the first one the common due date is a given constant,whereas in the second one the common due date is a decision variable. In each case, a general form of deterministic equivalent of the stochastic scheduling problem is obtained when the counting process N(t) related to the machine uptimes is a Poisson process. It is proved that an optimal schedule must be V-shaped in terms of weighted processing time when the agreeable weight condition is satisfied. Based on the V-shape property, two dynamic programming algorithms are proposed to solve both versions of the problem.

      • KCI등재

        STOCHASTIC SINGLE MACHINE SCHEDULING WITH WEIGHTED QUADRATIC EARLY-TARDY PENALTIES

        Zhao, Chuan-Li,Tang, Heng-Yong Korean Society of Computational and Applied Mathem 2008 Journal of applied mathematics & informatics Vol.26 No.5

        The problem of scheduling n jobs on a single machine is considered when the machine is subject to stochastic breakdowns. The objective is to minimize the weighted squared deviation of job completion times from a common due date. Two versions of the problem are addressed. In the first one the common due date is a given constant, whereas in the second one the common due date is a decision variable. In each case, a general form of deterministic equivalent of the stochastic scheduling problem is obtained when the counting process N(t) related to the machine uptimes is a Poisson process. It is proved that an optimal schedule must be V-shaped in terms of weighted processing time when the agreeable weight condition is satisfied. Based on the V-shape property, two dynamic programming algorithms are proposed to solve both versions of the problem.

      • KCI등재
      • Roles of mTOR and p-mTOR in Gastrointestinal Stromal Tumors

        Li, Jun-Chuan,Zhu, Hong-Yu,Chen, Ting-Xuan,Zou, Lan-Ying,Wang, Xiao-Yan,Zhao, Hui-Chuan,Xu, Jun Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

        Objective: This study aimed to examine the relationship between expression of mammal target of rapamycin (mTOR) and phosphorylation of mTOR (p-mTOR) protein in the PI3K/Akt/mTOR signaling pathways in gastrointestinal stromal tumors and relatiuonships with clinical factors. Methods: Immunohistochemistry was used to detect the expression of the associated proteins mTOR, p-mTOR, and phosphorylation of the tumor suppressor genes PTEN, P27, VEGF, and EGFR in 40 cases of gastrointestinal stromal tumors, with division into a very low and low risk group as well as a moderate and high risk group. Results: The positive rate of mTOR and p-mTOR was significantly increased in the moderate and high risk group compared with the very low and low risk group. The difference was statistically significant (P<0.05). When grouped according to size, the positive mTOR expression rate exhibited a statistical difference (P<0.05), which was significantly increased in the group of tumors larger than 5 cm. The difference in the positive mTOR and p-mTOR expression rate exhibit no statistical significance among the PTEN, P27, VEGF, and EGFR expression subgroups (P>0.05). Conclusion: The different expressions of mTOR and p-mTOR in the signal transduction pathway of gastrointestinal stromal tumor in the different degree-of-risk groups suggested that the mTOR and p-mTOR of the signal transduction pathway serve an important function in the occurrence and development of gastrointestinal stromal tumors.

      • KCI등재

        Weight Gain in Pregnancy, Maternal Age and Gestational Age in Relation to Fetal Macrosomia

        ( Yi Li ),( Qi-fei Liu ),( Dan Zhang ),( Ying Shen ),( Kui Ye ),( Han-lin Lai ),( Hai-qing Wang ),( Chuan-lai Hu ),( Qi-hong Zhao ),( Li Li ) 한국임상영양학회 2015 Clinical Nutrition Research Vol.4 No.2

        To investigate the possible risk factors related to macrosomia. Pregnant women and their newborns (n = 1041) were recruited from a cohort study in Maternal and Child Care Center of Hefei from January 2011 to July 2012. Questionnaires were applied to collect the demographic data besides the medical records. Detailed health records of the entire pregnancy were obtained using retrospective study. Meanwhile the data of neonatal outcomes was prospectively tracked. Associations between exposure risk factors and macrosomia were analyzed using Pearson’s chi squared test. Logistic regression models were used to assess the independent association between these potential predictors and macrosomia. The incidence of macrosomia of this cohort was 11.24% of which male: female = 2.55:1. Male incidence (8.07%) of macrosomia was higher than female (3.17%), p < 0.001. Body mass index (BMI) before pregnancy (pre-BMI), maternal height, parity were not independently associated with macrosomia; multiple logistic regression analysis indicated that macrosomia was mainly independently associated with weight gain in pregnancy (OR=1.14,95% CI [1.10-1.19]), maternal age (OR = 1.09,95% CI [1.03-1.15]) and gestational age (OR = 1.62,95% CI [1.31-1.99]), respectively. Our findings indicate that weight gain in pregnancy, maternal age and gestational age should be considered as independent risk factors for macrosomia.

      • Thin TiOxlayer as a voltage divider layer located at the quasi-Ohmic junction in the Pt/Ta2O5/Ta resistance switching memory

        Li, Xiang Yuan,Shao, Xing Long,Wang, Yi Chuan,Jiang, Hao,Hwang, Cheol Seong,Zhao, Jin Shi Royal Society of Chemistry 2017 Nanoscale Vol.9 No.6

        <P>Ta2O5 has been an appealing contender for the resistance switching random access memory (ReRAM). The resistance switching (RS) in this material is induced by the repeated formation and rupture of the conducting filaments (CFs) in the oxide layer, which are accompanied by the almost inevitable randomness of the switching parameters. In this work, a 1 to 2 nm-thick Ti layer was deposited on the 10 nm-thick Ta2O5 RS layer, which greatly improved the RS performances, including the much-improved switching uniformity. The Ti metal layer was naturally oxidized to TiOx (x < 2) and played the role of a series resistor, whose resistance value was comparable to the on-state resistance of the Ta2O5 RS layer. The series resistor TiOx efficiently suppressed the adverse effects of the voltage (or current) overshooting at the moment of switching by the appropriate voltage partake effect, which increased the controllability of the CF formation and rupture. The switching cycle endurance was increased by two orders of magnitude even during the severe current-voltage sweep tests compared with the samples without the thin TiOx layer. The Ti deposition did not induce any significant overhead to the fabrication process, making the process highly promising for the mass production of a reliable ReRAM.</P>

      • KCI등재

        Expression and Purification of a Functional Recombinant Aspartate Aminotransferase (AST) from Escherichia coli

        ( Li Hui Zou ),( Hai Jian Zhao ),( Dag Uang Wang ),( Meng Wang ),( Chuan Bao Zhang ),( Fei Xiao ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.7

        Aspartate aminotransferase (AST; E.C. 2.6.1.1), a vitamin B6-dependent enzyme, preferentially promotes the mutual transformation of aspartate and α-ketoglutarate to oxaloacetate and glutamate. It plays a key role in amino acid metabolism and has been widely recommended as a biomarker of liver and heart damage. Our study aimed to evaluate the extensive preparation of AST and its application in quality control in clinical laboratories. We describe a scheme to express and purify the 6His-AST fusion protein. An optimized sequence coding AST was synthesized and transformed into Escherichia coli BL21 (DE3) strain for protein expression. Ideally, the fusion protein has a volumetric productivity achieving 900 mg/l cultures. After affinity chromatography, the enzyme activity of purified AST reached 150,000 U/L. Commutability assessment between the engineered AST and standard AST from Roche suggested that the engineered AST was the better candidate for the reference material. Moreover, the AST showed high stability during long-term storage at -20ºC. In conclusion, the highly soluble 6His-tagged AST can become a convenient tool for supplying a much better and cheaper standard or reference material for the clinical laboratory.

      • KCI등재

        Effect of Crystal Structure and Hydrogen Bond of Thermoplastic Oxidized Starch on Manufacturing of Starch-Based Biomass Composite

        Chuan-Wei Zhang,Fang-Yi Li,Jianfeng Li,Qi Xie,Jie Xu,An-Fu Guo,Cheng-Zhao Wang 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.5 No.3

        Starch-based biomass composites were prepared with starch and plant fiber. In order to improve the properties of the compos ites, oxidized starches (OS) were prepared using hydroxyl peroxide as oxidizer, then glycerol was added into OS as plasticizer to produce thermoplastic oxidized starches (TPOS). Crystal structure, hydrogen bonds of TPOS were researched to gain comprehensive views on the mechanism of the property differences between the starch-based composites with native starch, OS and TPOS. The changes of crystal structure were analyzed by X-ray diffraction analysis. Starch intermolecular hydroxyl changes were investigated using the method of infrared spectrum analysis. It was found that the new hydrogen bonds were formed between the plasticizer, oxidizer and starch, and the starch intermolecular bonding force was weakened. The structure of starch crystallization was destructed in TPOS. Differential scanning calorimetry showed that cross reaction with oxidization and plasticization changed the crystal structure, glass transition process was not observed in TPOS. The tensile and compressive strengths of composite based on TPOS were improved greatly and mechanical properties were not weakened obviously with water content increased. All the results indicated that TPOS could improve the properties of starch-based composites.

      • KCI등재

        Numerical calculation and optimization designs in engine cooling water pump

        Li Wei,Wang Chuan,Shi Weidong,Zhao Xiaofan,Yang Yongfei,Pei Bing 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.5

        The cavitation damage in the Engine cooling water pump (ECWP) is the key factor that shortens the lifespan of automobile cooling systems, and causes vibration and noise. To improve cavitation performance and external characteristics of ECWP, three optimized models were designed on the basis of WP7 diesel ECWP. The whole flow fields in three models and the prototype pump were numerically simulated, employing the time averaged Navier-Stokes equation, the standard k-ε turbulent model and Zwart-Gerber-Belamri multiphase flow model by ANSYS-CFX software. Pressure distribution, turbulent kinetic energy distribution, bubble volume fraction distribution, external characteristics and cavitation performance of the prototype pump and optimized models were compared and analyzed. The results show that the external characteristics and cavitation performance of the optimized models are significantly better than that in the prototype pump. Through decreasing the inlet blade angle and wrap angle, extending the blade to inlets and extending a certain inclination in the blade, shock loss in blade inlet was reduced and so, the performance of pump will be improved. The flow condition at blade inlet will also be improved greatly, which in turn improves cavitation performance. When reducing the quantity of blades, the excretion coefficient will drop, flow area of blade inlet becomes bigger, but head has a little drop. And the pump optimized by reducing the quantity of blades has the optimal cavitation performance among three optimized models. With the decrease of impeller diameter, the absolute pressure in the critical cavitation point becomes bigger, the inlet bubble volume fraction at the same absolute pressure increases while cavitation performance gets worse. The obtained numerical results were compared with the experimental ones, and the outcome showed the same tendency between the two along with acceptable error.

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