在人机协作领域,模仿学习是广泛使用的机器人编程方法。在机器人对运动轨迹进行技能学习过程中,针对基于动态运动基元方法(dynamic movement primitives,DMP)只能从单条示教轨迹建模动作的局限性,提出了一种新的将高斯混合模型(gaussian...在人机协作领域,模仿学习是广泛使用的机器人编程方法。在机器人对运动轨迹进行技能学习过程中,针对基于动态运动基元方法(dynamic movement primitives,DMP)只能从单条示教轨迹建模动作的局限性,提出了一种新的将高斯混合模型(gaussian mixture model,GMM)、高斯混合回归(gaussian mixture regression,GMR)和改进的DMP三者相结合的运动轨迹模仿学习方法。该方法先将高斯噪声引入示教轨迹,消除由于示教数据中不可避免存在噪声等不平滑特征带来的不利影响;然后,为了减少单条示教轨迹的不确定性带来的动作建模误差,采用GMM从多条示教轨迹中对运动特征进行编码,使用GMR进行概率轨迹回归;其次,利用改进的DMP算法将轨迹进行泛化,提高机器人技能学习的适应性;最后,通过手写字母轨迹和协作机器人拖动轨迹技能学习试验验证了所提算法的有效性。展开更多
采用分子模拟方法研究氯化钠-光卤石反浮选体系中捕收剂十二烷基吗啉(DMP)选择性吸附氯化钠的机理.用Material Studio 4.0软件和COMPASS分子力场方法建立了DMP在氯化钠和光卤石两种矿物表面的吸附模型,并进行动力学模拟和能量优化,确立...采用分子模拟方法研究氯化钠-光卤石反浮选体系中捕收剂十二烷基吗啉(DMP)选择性吸附氯化钠的机理.用Material Studio 4.0软件和COMPASS分子力场方法建立了DMP在氯化钠和光卤石两种矿物表面的吸附模型,并进行动力学模拟和能量优化,确立了DMP在两种矿物表面的最佳吸附构型.结果表明,DMP分子通过其官能团中的O、N原子与氯化钠界面水结构中的H原子之间的氢键作用吸附在氯化钠表面,吸附作用能为-119.49kJ·mol-1,而光卤石界面水结构不能保持稳定排列,致使DMP直接作用在光卤石表面,吸附能为-37.97kJ·mol-1,在两种矿物共存体系中,这种吸附能差异导致了DMP在氯化钠表面的选择性吸附.展开更多
Participation of Pseudomonas putida-derived methyl phenol（dmp） operon and Dmp R protein in the biodegradation of phenol or other harmful, organic, toxic pollutants was investigated at a molecular level. Documentatio...Participation of Pseudomonas putida-derived methyl phenol（dmp） operon and Dmp R protein in the biodegradation of phenol or other harmful, organic, toxic pollutants was investigated at a molecular level. Documentation documents that P. putida has Dmp R protein which positively regulates dmp operon in the presence of inducers; like phenols. From the operon,phenol hydroxylase encoded by dmp N gene, participates in degrading phenols after dmp operon is expressed. For the purpose, the 3-D models of the four domains from Dmp R protein and of the DNA sequences from the two Upstream Activation Sequences（UAS）present at the promoter region of the operon were demonstrated using discrete molecular modeling techniques. The best modeled structures satisfying their stereo-chemical properties were selected in each of the cases. To stabilize the individual structures, energy optimization was performed. In the presence of inducers, probable interactions among domains and then the two independent DNA structures with the fourth domain were perused by manifold molecular docking simulations. The complex structures were made to be stable by minimizing their overall energy. Responsible amino acid residues, nucleotide bases and binding patterns for the biodegradation, were examined. In the presence of the inducers, the biodegradation process is initiated by the interaction of phe50 from the first protein domain with the inducers. Only after the interaction of the last domain with the DNA sequences individually, the operon is expressed. This novel residue level study is paramount for initiating transcription in the operon; thereby leading to expression of phenol hydroxylase followed by phenol biodegradation.展开更多
文摘采用分子模拟方法研究氯化钠-光卤石反浮选体系中捕收剂十二烷基吗啉(DMP)选择性吸附氯化钠的机理.用Material Studio 4.0软件和COMPASS分子力场方法建立了DMP在氯化钠和光卤石两种矿物表面的吸附模型,并进行动力学模拟和能量优化,确立了DMP在两种矿物表面的最佳吸附构型.结果表明,DMP分子通过其官能团中的O、N原子与氯化钠界面水结构中的H原子之间的氢键作用吸附在氯化钠表面,吸附作用能为-119.49kJ·mol-1,而光卤石界面水结构不能保持稳定排列,致使DMP直接作用在光卤石表面,吸附能为-37.97kJ·mol-1,在两种矿物共存体系中,这种吸附能差异导致了DMP在氯化钠表面的选择性吸附.
基金deeply indebted to DST-PURSE program 2012–2015 going on in Department of Biochemistry and Biophysics, University of Kalyani for providing different equipments and essential infrastructural supportDeep gratitude is extended to DBT sponsored Bioinformatics Infrastructure Facility in the Department of Biochemistry and Biophysics, University of Kalyani for the necessary support
文摘Participation of Pseudomonas putida-derived methyl phenol（dmp） operon and Dmp R protein in the biodegradation of phenol or other harmful, organic, toxic pollutants was investigated at a molecular level. Documentation documents that P. putida has Dmp R protein which positively regulates dmp operon in the presence of inducers; like phenols. From the operon,phenol hydroxylase encoded by dmp N gene, participates in degrading phenols after dmp operon is expressed. For the purpose, the 3-D models of the four domains from Dmp R protein and of the DNA sequences from the two Upstream Activation Sequences（UAS）present at the promoter region of the operon were demonstrated using discrete molecular modeling techniques. The best modeled structures satisfying their stereo-chemical properties were selected in each of the cases. To stabilize the individual structures, energy optimization was performed. In the presence of inducers, probable interactions among domains and then the two independent DNA structures with the fourth domain were perused by manifold molecular docking simulations. The complex structures were made to be stable by minimizing their overall energy. Responsible amino acid residues, nucleotide bases and binding patterns for the biodegradation, were examined. In the presence of the inducers, the biodegradation process is initiated by the interaction of phe50 from the first protein domain with the inducers. Only after the interaction of the last domain with the DNA sequences individually, the operon is expressed. This novel residue level study is paramount for initiating transcription in the operon; thereby leading to expression of phenol hydroxylase followed by phenol biodegradation.
