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1.
In the problem ofparts feeding we are given a class of feasible operations for reorienting a part, and we are asked to find a fixed sequence of these operations which is guaranteed to bring the part into a known goal orientation from any possible initial orientation. Goldberg addressed this problem in [2], and showed that, for planar polygonal parts, there is always a sequence of simple operations which can be performed by a simple parallel-jaw gripper, which is guaranteed to orient the part (up to symmetry) without the use of any sensor information; he also conjectured thatO(n) steps are sufficient.In this paper we prove Goldberg's conjecture by explicitly constructing plans of at most2n – 1 steps for orienting polygonal parts in this model. We also give a lower bound on the number of steps required for such plans to show that this upper bound is tight.Finally, we extend these results to the problem ofdistinguishing among a finite set of parts using minimal sensing. Specifically, we assume that we are given a set of known polygonal parts, and a parallel-jaw gripper able to sense the distance between its jaws upon closure. We construct a simple oblivious plan of linear complexity which, when presented with a polygonal part, determines the index of this part.This research was supported in part by the NSF under Grant CCR-9207422, and by a Zumberge Fellowship. A preliminary version of this paper appeared in theProceedings of the Fourth Canadian Conference on Computational Geometry [1]. 相似文献
2.
目前主流的网络安全防护体系是外嵌的,安全体系与业务体系分离,安全产品相互孤立,在防护能力上难以高效应对越来越复杂的网络安全挑战。网络安全从外向内进行强基,势在必行。将网络安全的业务场景归纳为组织、厂商、监管和威胁四方视角,各视角具有不同的业务目标。从四方视角的共性和个性出发,系统性归纳网络安全生态的能力需求,提出内禀安全方法论。内禀安全能力是指ICT组件原生支撑监测、防护和溯源等安全功能的能力。内禀安全能力对网络安全具有基础支撑作用,本身不是最终的安全功能实现,与现有的“内生安全”“内设安全”等方法论所针对的问题不同。内禀安全强调网络组件内在的安全赋能禀赋,有两种方式可以发掘这种禀赋,一是通过先天安全能力激活,二是外嵌能力内化,对外在逻辑上表现出自体免疫。此类组件的优势之一在于业务与安全的内聚,能够透明化感知安全态势、定制化配置安全策略、贴身化执行安全保护;优势之二在于将业务功能与安全功能进行合并封装,简化整体工程架构,降低网络管理复杂度。进一步提出了内禀安全支撑能力框架,对符合内禀安全理念的安全能力进行归纳和枚举,将安全支撑能力分为采集、认知、执行、协同和弹复5类,并进一步介绍各类能力的子类型和基础ICT技术。基于该框架,介绍了典型安全业务场景在内禀安全理念下的增强实现。 相似文献
3.
F. Hooshmand Khaligh 《国际生产研究杂志》2016,54(2):579-590
In this study, a multistage stochastic programming (SP) model is presented for a variant of single-vehicle routing problem with stochastic demands from a dynamic viewpoint. It is assumed that the actual demand of a customer becomes known only when the customer is visited. This problem falls into the category of SP with endogenous uncertainty and hence, the scenario tree is decision-dependent. Therefore, nonanticipativity of decisions is ensured by conditional constraints making up a large portion of total constraints. Thus, a novel approach is proposed that considerably reduces the problem size without any effect on the solution space. Computational results on some test problems are reported. 相似文献
4.
Personalized Cancer Immunotherapy: Personalized Cancer Immunotherapy via Transporting Endogenous Tumor Antigens to Lymph Nodes Mediated by Nano Fe3O4 (Small 38/2018)
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5.
Personalized Cancer Immunotherapy via Transporting Endogenous Tumor Antigens to Lymph Nodes Mediated by Nano Fe3O4
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Binghua Wang Jingyi An Huifang Zhang Shudong Zhang Huijuan Zhang Lei Wang Hongling Zhang Zhenzhong Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(38)
While immunotherapy has a tremendous clinical potential to combat cancer, immune responses generated by conventional cancer immunotherapy remain not enough to completely eliminate tumors, mainly due to the tumor's immunosuppressive microenvironment and heterogeneity of tumor immunogenicity. To improve antitumor immune responses and realize personalized immunotherapy, in this report, endogenous tumor antigens (ETAs) that dynamically present on tumor cells are transported to lymph nodes (LNs). Based on the hypothesis that nano Fe3O4 (≈10 nm) could serve as the nanocarrier for transporting ETAs from the tumor to LNs, we wondrously find that Fe3O4 has a tremendous potential to improve cancer immunotherapy, because of its excellent protein‐captured efficiency and LNs‐targeted ability. To ensure the optimal ETAs‐bound efficiency of Fe3O4, a core–shell formulation (denoted as Ce6/Fe3O4‐L) is developed and specific release of Fe3O4 in tumor is enabled. These findings provide a simple and general strategy for boosting cytotoxic T‐cell response and realizing personalized cancer immunotherapy simultaneously. 相似文献
6.
针对高职教育存在不能满足社会人才需求的状况,在分析高职教育自身原因基础上,提出以就业为导向的教学改革思想。以就业为导向的教学,是高职教育追求的目标,是实现人才培养与学生"零距离就业"的根本途径。结合我校近几年软件人才培养模式,总结经验,提出新的以就业为导向培养学生综合能力的教学改革思路,实践证明该教学改革有很好的发展前景。 相似文献
7.
随着“委托-代理”的公司经营模式兴起,关于高管激励机制与绩效之间相关关系的研究应运而生.文中在单一方程模型与联立方程模型基础上,运用Eviews软件对陕西省上市公司的数据进行处理,并采用经济附加值(EconomicValueAdded,EVA)作为衡量企业经营绩效的指标,从内生性的视角研究上市公司高管激励机制与绩效之间的关系.结果表明高管激励机制与绩效之间不但存在着正相关关系,而且两者之间存在内生性关系.而对于两者的相互作用机理方面还需要进一步研究. 相似文献
8.
为了研究厌氧-好氧工艺处理垃圾渗滤液的脱氮性能,采用ASBR联合脉冲进水SBR(脉冲SBR)处理高氨氮实际垃圾渗滤液。ASBR的水力停留时间为2d;中间水箱调节脉冲SBR的进水C/N(3~5)和NH4+-N浓度;脉冲SBR采用3次等量进水模式,运行周期分为4个缺氧段和3个好氧段,不投加外碳源,缺氧4利用污泥内碳源进行反硝化。结果表明,串联运行时期(157d)系统获得了高效的脱氮性能。ASBR进水COD为7 338~10 445mg.L-1,去除率在83%以上;脉冲SBR进水NH4+-N浓度分4个阶段逐步提高至912.0±41.7mg.L-1,总氮(TN)去除率在90%以上,出水总氮小于40mg.L-1;系统COD和总氮去除率分别在87%和97%以上。单个缺氧4进程内的内源反硝化速率(DNR)会由快变慢,而其平均理论内源反硝化速率(TDNRm)达到了1.531mgN.h-1.gMLVSS-1。在不使用物化预处理和不投加外碳源的情况下实现了对渗滤液的深度脱氮。 相似文献
9.
Halari Rozmin; Hines Melissa; Kumari Veena; Mehrotra Ravi; Wheeler Mike; Ng Virginia; Sharma Tonmoy 《Canadian Metallurgical Quarterly》2005,119(1):104
Sexually dimorphic cognitive performance in men (n=42) and women (n=42) was related to testosterone, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone binding globulin, measured in 10-ml blood samples collected between 0900 and 1030 and, among women, during the follicular phase of the menstrual cycle. Significant sex differences favored men on spatial tasks (Mental Rotation and Judgment of Line Orientation) and on an inhibition task and favored women on a verbal task (category fluency). However, there were no significant relationships between any of the hormones and cognitive performance, suggesting that there are few, if any, consistent, substantial relationships between endogenous, nonfluctuating levels of gonadal hormones or gonadotropins and these cognitive abilities in men or women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
The authors propose that there are 2 different mechanisms whereby spatial cues capture attention. The voluntary mechanism is the strategic allocation of perceptual resources to the location most likely to contain the target. The involuntary mechanism is a reflexive orienting response that occurs even when the spatial cue does not indicate the probable target location. Voluntary attention enhances the perceptual representation of the stimulus in the cued location relative to other locations. Hence, voluntary attention affects performance in experiments designed around both accuracy and reaction time. Involuntary attention affects a decision as to which location should be responded to. Because involuntary attention does not change the perceptual representation, it affects performance in reaction time experiments but not accuracy experiments. The authors obtained this pattern of results in 4 different versions of the spatial cuing paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献