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1.
Flow shop rescheduling problem under rush orders 总被引：1，自引：0，他引：1
INTRODUCTION Rescheduling problem in manufacturing system is considered as a particularly hard combinatorial optimization problem,closely related with uncer-tainty caused by exterior business environment and interior production conditions.Production resched-uling is a common practice in manufacturing compa-nies all over the world.Four sources of production disturbances have been identified:(1)incorrect work;(2)machine breakdowns;(3)rework due to quality problem;and(4)rush orders(Rangsarit… 相似文献
2.
利用铜仁市6个气象站1970年～2010年月平均气温、年平均气温资料,采用线性拟合法、Mann-Kendall 突变检验法等方法对铜仁市近40年的气温变化特征进行分析。结果表明：1970年～2010年铜仁市的气温呈现明显的上升趋势,其中德江站增幅最高,松桃站增幅最低;通过Mann-Kendall分析,近40年铜仁市年平均气温出现突变,显著突变点在1998年。 相似文献
3.
Yan-qin Huang Ying Yuan Wei-ting Ge Han-guang Hu Su-zhan Zhang Shu Zheng 《Journal of Zhejiang University. Science. B》2010,11(9):647-653
Objective
The purpose of this study was to determine the unique and universal features of microsatellite instability-high (MSI-H) colorectal cancer (CRC) and MSI-H gastric cancer (GC) in the Chinese population. 相似文献4.
李晓虹 《广播电视大学学报》2005,4(3):1-4
20世纪散文中，乡土散文始终占有重要位置，现当代作家创作的乡土散文有共同的内在品格，也有不断生成变化的不同的因素。首先，在写作乡村题材的作品时，他们都已离开乡村，出走造成了压力和精神张力。现代乡土散文作家是在承认“乡下人”立场的前提下时时进行精神回望的：其次，就作家笔下的乡村图景而言，现代作家的描写是丰富而复杂的，但都抱有一种悲剧情怀，当代乡村散文经历了从诗意赞美到多种情调共存的过程；再次，现当代都有一些作家有意在乡村描写中寄寓自己的生命理想，表现了具有形上意义的家园之感。 相似文献
5.
Sun Jie Huang He Zhu Yuan-yuan Lan Jian-ping Li Jing-yuan Lai Xiao-yu Yu Jian 《Journal of Zhejiang University. Science. B》2005,6(12):1141-1147
Objective: Detecting the expression and mutation of human telomeric repeat binding factor (hTRF1) in 10 malignant hematopoietic cell line cells on the base of determining its genomic structure and its four pseudogenes
to clarify if hTRF1 mutation is one of the factors of the activation of telomerase. Methods: hTRF1cDNA sequences were obtained from GenBank, its genome structure and pseudogenes were forecasted by BLAST and other biology
information programs and then testified by sequencing. Real-time RT-PCR was used to detect the expression of hTRF1mRNA in 10 cell line cells, including myelogenous leukemia cell lines K562, HL-60, U-937, NB4, THP-1, HEL and Dami; lymphoblastic
leukemia cell lines 6T-CEM, Jurkat and Raji. Telomerase activities of cells were detected by using telomeric repeat amplification
(TRAP)-ELISA protocol. PCR and sequencing were used to detect mutation of each exon of hTRF1 in 10 cell line cells. Results: hTRF1 gene, mapped to 8q13, was divided into 10 exons and spans 38.6 kb. Four processed pseudogenes of hTRF1 located on chromosome 13, 18, 21 and X respectively, was named as ψhTRF1-13, ψhTRF1-18, ψhTRF1-21 and ψhTRF1-X respectively. All cell line cells showed positive telomerase activity. The expression of hTRF1 was significantly lower in malignant hematopoietic cell lines cells (0.0338, 0.0108:_0.0749) than in normal mononuclear cells
(0.0493, 0.0369:_0.128) (P=0.004). But no significant mutation was found in all exons of hTRF1 in 10 cell line cells. Four variants were found in part of intron 1, 2 and 8 of hTRF1. Their infection on gene function is unknown and needs further studies. Conclusion: hTRF1 mutation is probably not one of the main factors for telomerase activation in malignant hematopoietic disease.
Project supported by the National Basic Research Program (973) of China (No. 2002CB713700) and the National Natural Science
Foundation of China (No. 39870339) 相似文献
6.
7.
王中华 《辽宁科技学院学报》2009,11(1):19-20
文章设计了一个求解包装问题的演化算法,在演化算法中采用了行之有效的个体编码方案、选择策略、杂交算子及变异算子,并通过实验进行算法性能的验证和分析。实验结果表明,该算法能够在很短的时间内找到包装问题的近似最优解。 相似文献
8.
Yu-hua Liang Xiao-ling Chen Zhong-sheng Yu Chun-yue Chen Sheng Bi Lian-gen Mao Bo-lin Zhou Xian-ning Zhang 《Journal of Zhejiang University. Science. B》2009,10(1):29-34
Spinal muscular atrophy (SMA) is a disorder characterized by degeneration of lower motor neurons and occasionally bulbar motor
neurons leading to progressive limb and trunk paralysis as well as muscular atrophy. Three types of SMA are recognized depending
on the age of onset, the maximum muscular activity achieved, and survivorship: SMA1, SMA2, and SMA3. The survival of motor
neuron (SMN) gene has been identified as an SMA determining gene, whereas the neuronal apoptosis inhibitory protein (NAIP) gene is considered to be a modifying factor of the severity of SMA. The main objective of this study was to analyze the
deletion of SMN1 and NAIP genes in southern Chinese children with SMA. Here, polymerase chain reaction (PCR) combined with restriction fragment length
polymorphism (RFLP) was performed to detect the deletion of both exon 7 and exon 8 of SMN1 and exon 5 of NAIP in 62 southern Chinese children with strongly suspected clinical symptoms of SMA. All the 32 SMA1 patients and 76% (13/17)
of SMA2 patients showed homozygous deletions for exon 7 and exon 8, and all the 13 SMA3 patients showed single deletion of
SMN1 exon 7 along with 24% (4/17) of SMA2 patients. Eleven out of 32 (34%) SMA1 patients showed NAIP deletion, and none of SMA2 and SMA3 patients was found to have NAIP deletion. The findings of homozygous deletions of exon 7 and/or exon 8 of SMN1 gene confirmed the diagnosis of SMA, and suggested that the deletion of SMN1 exon 7 is a major cause of SMA in southern Chinese children, and that the NAIP gene may be a modifying factor for disease severity of SMA1. The molecular diagnosis system based on PCR-RFLP analysis can
conveniently be applied in the clinical testing, genetic counseling, prenatal diagnosis and preimplantation genetic diagnosis
of SMA.
Project supported by the National Natural Science Foundation of China (No. J0710043), and the Natural Science Foundation of
Zhejiang Province (No. 2007C33049), China 相似文献
9.
Morphological and biochemical responses of Oryza sativa L. (cultivar MR219) to ion beam irradiation 总被引：1，自引：0，他引：1
Anna Pick Kiong Ling Ying Chian Ung Sobri Hussein Abdul Rahim Harun Atsushi Tanaka Hase Yoshihiro 《Journal of Zhejiang University. Science. B》2013,14(12):1132-1143
Objective
Heavy ion beam, which has emerged as a new mutagen in the mutation breeding of crops and ornamental plants, is expected to result in the induction of novel mutations. This study investigates the morphological and biochemical responses of Oryza sativa toward different doses of carbon ion beam irradiation.Methods
In this study, the dry seeds of O. sativa were irradiated at 0, 20, 40, 60, 80, 100, and 120 Gy, followed by in-vitro germination under controlled conditions. Morphological and biochemical studies were conducted to investigate the morphological and physiological responses of O. sativa towards ion beam irradiation.Results
The study demonstrated that low doses (10 Gy) of ion beam have a stimulating effect on the height, root length, and fresh weight of the plantlets but not on the number of leaves. Meanwhile, doses higher than 10 Gy caused reductions in all the morphological parameters studied as compared to the control samples. The highest total soluble protein content [(2.11±0.47) mg/g FW] was observed in plantlets irradiated at 20 Gy. All irradiated plantlets were found to have 0.85% to 58.32% higher specific activity of peroxidase as compared to the control samples. The present study also revealed that low doses of ion beam (10 and 20 Gy) had negligible effect on the total chlorophyll content of O. sativa plantlets while 40 Gy had a stimulating effect on the chlorophyll content. Plantlets irradiated between 40 to 120 Gy were shown to be 0.38% to 9.98% higher in total soluble nitrogen content which, however, was not significantly different from the control samples.Conclusions
Carbon ion beam irradiation administered at low to moderate doses of 10 to 40 Gy may induce O. sativa mutants with superior characteristics. 相似文献10.
Feng-wei Song Bin-bin Chen Zhao-hui Sun Li-ping Wu Su-juan Zhao Qi Miao Xia-jing Tang 《Journal of Zhejiang University. Science. B》2013,14(6):479-486