Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Qinghai-Tibet Plateau is important ecological security barrier of China and even Asia, and one of biodiversity conservation hotspots. Ensuring ecological security and protecting biodiversity are key tasks of ecological protection in Qinghai-Tibet Plateau. In Qinghai-Tibet Plateau, wildlife is very rich but there are many threatened species. During past 15 years, ecosystem pattern is stable, and ecosystem quality generally elevates in Qinghai-Tibet Plateau. Correspondingly, water retention, soil retention, and sandstorm prevention are improved and the trend of ecological degradation is suppressed. The construction of natural reserves and the implementation of ecological protection projects in Qinghai-Tibet Plateau contribute to the improvement of ecological security barrier function. However, due to the impacts of warm-wet tendency and human activities, Qinghai-Tibet Plateau is facing a series of ecological degradation risks, including frozen soil area withering, marsh reduction, wildlife habitat degradation, alien invasion, and ecosystem degradation. To further protect Qinghai-Tibet Plateau’s ecological security barrier, the following measures could be taken, namely, optimizing spatial pattern of natural protected area, establishing natural protected area system mainly based on national park group, and implementing ecological protection and restoration projects.
Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究妊娠后期能量饲喂水平对母猪繁殖性能和血脂代谢相关指标的影响。选用长白×大白杂交经产妊娠母猪48头，于妊娠第85天开始按照体重和胎次随机分为低、中等、高和极高4种不同能量饲喂水平组（n=12），4组能量饲喂水平分别为1.12、1.32、1.52和1.72倍维持代谢能需要量，并分别命名为1.12M、1.32M、1.52M和1.72M组。试验饲粮为玉米-豆粕型饲粮，代谢能（ME）为13.38 MJ/kg，粗蛋白质（CP）含量为15.09%。中等能量饲喂水平参照NRC（2012）妊娠母猪有效代谢能推荐值，低、高、极高能量饲喂水平在此基础上分别减少15%、增加15%和增加30%。1.12M、1.32M、1.52M和1.72M组母猪的日采食量分别为2.17、2.56、2.94和3.33 kg/d，代谢能摄入量分别为29.10、34.23、39.37、44.50 MJ/d。试验期为23 d。结果显示：随着妊娠后期能量饲喂水平的增加，哺乳母猪的平均日采食量显著下降（P<0.05）。妊娠100 d时，随着能量饲喂水平的增加，母猪血清总胆固醇和低密度脂蛋白浓度线性升高（P<0.05），血清总胆固醇、甘油三酯和高密度脂蛋白浓度二次升高（P<0.05）。在妊娠后期，母猪血清总胆固醇浓度随着妊娠时间的延长而显著降低（P<0.05）；血清高密度脂蛋白和低密度脂蛋白浓度在妊娠107 d时显著低于妊娠100和85 d时（P<0.05）；血清甘油三酯浓度在妊娠100 d时显著高于妊娠85、107 d时（P<0.05），且妊娠107 d时显著高于妊娠85 d时（P<0.05）。由此可见，妊娠后期增加能量饲喂水平可降低母猪哺乳期的采食量；妊娠后期母猪血脂处于生理较高水平，在此基础上增加能量饲喂水平可进一步引起血清甘油三酯、高密度脂蛋白、低密度脂蛋白和总胆固醇浓度升高。
Subjects: Biology >> Zoology submitted time 2018-12-20 Cooperative journals: 《动物营养学报》
Abstract：机体各组织氨基酸代谢过程中产生的氨及肠道微生物分解生成的氨吸收均可进入血液，形成血氨。血氨浓度过高会严重危害动物健康，已逐渐成为畜牧业关注的问题。本文综述了血氨的代谢特性及对动物健康的影响，以为畜牧业实际生产中血氨的检测提供数据参考。
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-08-13 Cooperative journals: 《计算机应用研究》
Abstract： This paper proposed a storage format HMEC (Hybrid Multiple ELL and CSR) of sparse matrix to solve large sparse linear equations on GPU. Firstly, we optimized the storage structure of the coefficient matrix by reordering. Secondly, we stored the coefficient matrix in a certain scale block. Then we adopt an approach by combining ELL and CSR storage format to adapt to different characteristics of blocks. At last, we took Bi-Conjugate Gradient Stabilized (BICGStab) and Conjugate Gradient (CG) iterative methods to solve large sparse linear systems, they are respectively preconditioned by incomplete-LU and incomplete-Cholesky factorization for asymmetric and symmetric positive definite linear matrices. Experiments show that comparing the way by storing sparse matrices in HMEC format with other ways by storing in the common storage format, the acceleration of the best available we can get are 31.89% and 17.50%.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-05-18 Cooperative journals: 《计算机应用研究》
Abstract： For the parallel machine scheduling with controllable processing times (PMS-CPT) , this paper proposed a scheduling problem for optimizing tardiness and energy cost. First, this article developed an integer linear programming (ILP) model for the proposed scheduling problem in order to facilitate the CPLEX solver. Second, this paper established a hybrid teaching-learning-based optimization (HTLBO) algorithm to quickly obtain satisfactory solutions. This algorithm adopted a new coding and decoding method according to the nature of the proposed parallel machine scheduling problem, which overcame the weakness of standard teaching-learning-based optimization algorithm that could not be directly applied to discrete problems. Meanwhile, a local optimizer was proposed based on variable neighborhood search (VNS) , which aimed to enhance the performance of the hybrid algorithm. Finally, the simulations were conducted to solve instances of PMS-CPT. The experimental results demonstrate the feasibility and validity of the proposed ILP model and hybrid algorithm.
Subjects: Biology >> Zoology submitted time 2017-10-10 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究低蛋白质饲粮添加α–酮戊二酸(α-ketoglutarate，AKG)对生长猪氮以及钙、磷代谢的影响。试验选用初始体重为（34.98±2.18） kg的健康三元杂交（杜×长×大）猪18头，按体重相近、性别比例相同原则随机分为3组，每组6个重复，每个重复1头。各组AKG的添加水平分别为0（对照组）、1%和2%。先进行为期14 d的饲养试验，观察生长性能；然后进行消化代谢试验，试验期为7 d，前5 d为预试期，后2 d为粪尿收集期（全收粪法）。结果表明：1）1%AKG添加组有改善35～45 kg生长猪生长性能的趋势，具体表现为提高平均日增重（P=0.194 2）和平均日采食量（P=0.258 3），降低料重比（P=0.419 7）。2）随着AKG添加水平提高，尿氮含量有下降趋势（P=0.143 2），粪氮、总氮含量及总氮排放率极显著降低（P0.05）。由此可见，在35～45 kg的生长猪饲粮中添加1%～2%AKG可有效降低机体氮、钙、磷排放，提高氮及钙、磷的利用率和日增重。
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