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Uncertainties on the Luminescence Ages and Anomalous Fading

It is well known that some minerals give underestimated luminescence ages due to anomalous fading. The anomalous fading follows a logarithmic decay law characterized by its slope, the socalled fading rate or g-value. Using the fading rate, Huntley and Lamothe (2001) suggested some correction for the fading underestimation of young samples (<40-50 ka). For polymineral fine grains, we observe a fading rate of 0-4%/decade for TL and BL-OSL and 4-6%/decade for IR-OSL. Extending the laboratory observation to archaeological age, the underestimation on the age for 10 ka is estimated to a mean of 5% for TL, 10% for BL-OSL and 45% for IR-OSL. Due to the non-linearity of the Huntley and Lamothe's fading correction, the contribution of the fading to the total uncertainty is estimated by a Monte-Carlo simulation. The inference on dating shows that the uncertainty on the anomalous fading can be a significant term of the combined uncertainty on the age, even for low fading rates.

Introduction Modern radiotherapy techniques such as intensity modulated radiotherapy (IMRT), volumetric modulated arch therapy (VMAT) and image guided adaptive brachytherapy (IGABT) enable delivery of high doses to the target volume without escalating dose to organs at risk (OAR), offering the possibility of better local control while preserving good quality of life. 1 , 2 Highly conformal radiation techniques and sharp dose falloff make the accuracy and precision of every step in treatment planning and delivery extremely important. Uncertainties in the process

Abstract

The gripper finger design is a recurring problem in many robotic grasping platforms used in industry. The task of switching the gripper configuration to accommodate for a new batch of objects typically requires engineering expertise, and is a lengthy and costly iterative trial-and-error process. One of the open challenges is the need for the gripper to compensate for uncertainties inherent to the workcell, e.g. due to errors in calibration, inaccurate pose estimation from the vision system, or object deformation. In this paper, we present an analysis of gripper uncertainty compensating capabilities in a sample industrial object grasping scenario for a finger that was designed using an automated simulation-based geometry optimization method (, ). We test the developed gripper with a set of grasps subjected to structured perturbation in a simulation environment and in the real-world setting. We provide a comparison of the data obtained by using both of these approaches. We argue that the strong correspondence observed in results validates the use of dynamic simulation for the gripper finger design and optimization.

8. References 1. Oberkampf, W.L., Helton J.C., Joslyn C.A., Wojtkiewicz S.F., Ferson S.: Challenge Problems: Uncertainty in System Response Given Uncertain Parameters, Reliability Engineering and System Safety, vol. 85, no. 1-3, 2004. 2. Utkin L.V., Coolen F.: Imprecise reliability: An introductory overview. In: Intelligence in Reliability Engineering. Ed. by G. Levitin. Springer Berlin Heidelberg, 2007. 3. Coit D., Jin T., Wattanapong Sakorn N.: System optimization with Component Reliability estimation uncertainty: A multi-criteria Approach, IEEE Transactions on

REFERENCES Beven, K., 2007. Towards integrated environmental models of everywhere: Uncertainty, data and modelling as a learning process. Hydrol. Earth Syst. Sci., 11, 460–467. Beven, K.J., Binley, A.M., 1992. The future of distributed models: Model calibration and uncertainty prediction. Hydrological Processes, 6, 279–298. Campos, J.N.B., Souza Filho, F.A., Lima, H.V.C., 2014. Risks and uncertainties in reservoir yield in highly variable intermittent rivers: Case of the Castanhão Reservoir in semi-arid Brazil. Hydrological Sciences Journal, 59, 6, 1184

, Proceedings of the 11th IFToMM World Congress on the Theory of Machines and Mechanisms, Tianjin, China , pp. 1209-1213. Chablat, D., Wenger, P. and Merlet, J.-P. (2002). Workspace analysis of the Orthoglide using interval analysis, Advances in Robot Kinematics, Caldes de Malavalla, Spain , pp. 397-406. Clerentin, A., Delahoche, L., Brassart, E. and Izri, S. (2003). Imprecision and uncertainty quantification for the problem of mobile robot localization, Proceedings of the Performance Metrics for Intelligent Systems Workshop, Gaithersburg, MD, USA . Daney, D., Andreff, N

Abstract

In large-scale power systems, the wide-area damping controller (WADC) using remote input signals is an effective device that can be applied to deal with poor inter-area oscillation damping. However, its control effect will be degraded by communication uncertainties such as variable time delays in both input and output sides of WADC, partial and complete communication failures. This paper focuses on a new WADC design by regarding communication uncertainties. Such uncertainties are mathematically formulated and analyzed in order to signify its impact on the oscillatory stability. The signal restoration of input and output pairs of WADC is proposed to alleviate an adverse effect of communication uncertainties. Simulation study in an IEEE 50-machine 145-bus test system elucidates that the proposed WADC is superior to that of the conventional WADC without considering communication uncertainties in both performance and robustness.

Abstract

Radio Frequency Identification (RFID) is still a relatively new technology for many manufacturing and logistics companies. These companies experience uncertainties about RFID implementation, so they take steps to mitigate them. This article presents multiple case studies to design a conceptual framework to mitigate such barriers. The goal of this research was to test propositions that companies: often are not convinced about the maturity and performance of RFID technology; perform typical actions to test uncertainties; and need proof of the benefits of RFID technology before implementation. It was demonstrated that companies conduct proof of RFID technology activities (demonstrations and reference visits) to test RFID performance. These are required to test the technology in operation. Conclusions of this research may serve RFID systems providers and end users of technology by facilitating a better understanding of decision making processes during early phases of RFID implementation.

-628. Utkin, V. I. (1992). Sliding Modes in Control and Optimization , Springer-Verlag, Berlin. Utkin, V. I. and Shi, J. (1996). Integral sliding mode in systems operating under uncertainty conditions, Proceedings of the 35th Conference on Decision and Control, Kobe, Japan , pp. 4591-4596. Wang, L. X. (1997). A Course in Fuzzy Systems and Control , Prentice Hall, Englewood Cliffs, NJ. Xia, Y. and Jia, Y. (2003). Robust sliding mode control design of uncertain time-delay systems: An LMI approach, IEEE Transactions on Automatic Control   48 (6): 624-628.

necessary to use probabilistic approaches to provide reliable design of the structure. In fact, the spatial variability of soils is a major source of SSI problems and the dynamic SSI problem should be modelled into a stochastic from word. [ 9 , 10 , 11 ] However, to what extent can uncertainty in soil parameters affect the structure response to address the SSI problem? The response of a structure to a seismic excitation might increase or decrease depending on the characteristics of the ground motion and dynamic properties of the structure and the underlying soil. [ 3