We consider in this paper fault-tolerant mixed-criticality scheduling, where heterogeneous safety guarantees must be provided to functionalities (tasks) of varying criticalities (im-portances). We model explicitly the...
详细信息
ISBN:
(纸本)9781479930173
We consider in this paper fault-tolerant mixed-criticality scheduling, where heterogeneous safety guarantees must be provided to functionalities (tasks) of varying criticalities (im-portances). We model explicitly the safety requirements for tasks of different criticalities according to safety standards, assuming hardware transient faults. We further provide analysis techniques to bound the effects of task killing and service degradation on the system safety and schedulability. Based on our model and analysis, we show that our problem can be converted to a conventional mixed-criticality schedul-ing problem. Thus, we broaden the scope of applicability of the conventional mixed-criticality scheduling techniques. Our proposed techniques are validated with a realistic flight management system application and extensive simulations. Copyright 2014 ACM.
End-to-end transport protocols perform poorly in mobile environments, primarily due to the frequent route breaks induced by node mobility. We present a framework for hop-by-hop transport protocols and propose a new re...
详细信息
Mathematical modeling for gene regulative networks (GRNs) provides an effective tool for hypothesis testing in biology. A necessary step in setting up such models is the estimation of model parameters, i.e., an optimi...
详细信息
ISBN:
(纸本)9781605583259
Mathematical modeling for gene regulative networks (GRNs) provides an effective tool for hypothesis testing in biology. A necessary step in setting up such models is the estimation of model parameters, i.e., an optimization process during which the difference between model output and given experimental data is minimized. This parameter estimation step is often difficult, especially for larger systems due to often incomplete quantitative data, the large size of the parameter space, and non-linearities in system behavior. Addressing the task of parameter estimation, we investigate the influence multiobjectivization can have on the optimization process. On the example of an established model for the segment polarity GRN in Drosophila, we test different multiobjectivization scenarios compared to a singleobjective function proposed earlier for the parameter optimization of the segment polarity network model. Since, instead of a single optimal parameter setting, a set of optimal parameter settings exists for this GRN, the comparison of the different optimization scenarios focuses on the capabilities of the different scenarios to identify optimal parameter settings showing good diversity in the parameter space. By embedding the objective functions in an evolutionary algorithm (EA), we show the superiority of the multiobjective approaches in exploring the model's parameter space. Copyright 2009 ACM.
Multiobjective optimization in general aims at learning about the problem at hand. Usually the focus lies on objective space properties such as the front shape and the distribution of optimal solutions. However, struc...
详细信息
ISBN:
(纸本)9781450300728
Multiobjective optimization in general aims at learning about the problem at hand. Usually the focus lies on objective space properties such as the front shape and the distribution of optimal solutions. However, structural characteristics in the decision space can also provide valuable insights. In certain applications, it may even be more important to find a structurally diverse set of close-to-optimal solutions than to identify a set of optimal but structurally similar solutions. Accordingly, multiobjective optimizers are required that are capable of considering both the objective space quality of a Pareto-set approximation and its diversity in the decision space. Although NSGA, one of the first multiobjective evolutionary algorithms, explicitly considered decision space diversity, only a few other studies address that issue. It therefore is an open research question how modern multiobjective evolutionary algorithms can be adapted to search for structurally diverse high-quality Pareto-set approximations. To this end we propose an approach to integrate decision space diversity into hypervolume-based multiobjective search. We present a modified hypervolume indicator and integrate it into an evolutionary algorithm. The proof-of-principle results show the potential of the approach and indicate further research directions for structure-oriented multiobjective search. Copyright 2010 ACM.
Nowadays, the reliability and performance of modern embedded multi-processor systems is threaten by the everincreasing power densities in integrated circuits, and a new additional goal of software synthesis is to redu...
详细信息
The transmission matrix method is used to analyze the influence of incident light on coupled resonators. Two different types of incident light on the same coupled resonator geometry are shown to lead to different syst...
详细信息
The transmission matrix method is used to analyze the influence of incident light on coupled resonators. Two different types of incident light on the same coupled resonator geometry are shown to lead to different system transmission features. The EIT-like phenomenon occurs in the type I case with the transmission being symmetric around the zero-single-pass-phase-shift frequency. In the type Ⅱcase the resonant frequency has a blue shift corresponding to the increasing coupling strength between the two ring resonators. Also, the critical-coupling-like condition exists in the type Ⅱconfiguration to maintain the zero-single pass-phase-shift frequency. The incident light, as well as the geometry, partially determine the mode interference in the coupled ring resonator system.
The tapered asymmetric directional coupler has the potential to realize high fabrication tolerance and high transmission efficiency on-chip mode multiplexer. However, the geometry parameter selection of tapered struct...
详细信息
The tapered asymmetric directional coupler has the potential to realize high fabrication tolerance and high transmission efficiency on-chip mode multiplexer. However, the geometry parameter selection of tapered structure remains empirical. In this paper, we propose a design method for the tapered structure based on genetic algorithm. Combined with the adjusted coupling equations and interpolation method, lowtime-cost optimization can be realized. Three mode multiplexers(TE0&TE1, TE0&TE2 and TE0&TE5)are designed by our method. According to simulation results, the insertion loss of the designed devices is lower than 1.8 dB and the crosstalk is lower than-15 dB when the fabrication error is within required range(±10 nm for TE0&TE2 and TE0&TE5, and ±20 nm for TE0&TE1) in the bandwidth of 1.5–1.6 μm. In addition, the entire optimization process takes only 2 h for each device, which is around the time cost of a single 3 D simulation.
The impact of mobility on the link and route lifetimes in ad hoc networks is of major importance for the design of efficient MAC and network layer protocols. Up to now, no real-life measurements were used to study the...
详细信息
ISBN:
(纸本)1595933603
The impact of mobility on the link and route lifetimes in ad hoc networks is of major importance for the design of efficient MAC and network layer protocols. Up to now, no real-life measurements were used to study the effect of node mobility on link and route lifetime distributions. In this paper, we present data gathered from a real network of 20 test users and analyze it with regard to link and route lifetime distributions. Besides link breakage due to node mobility, links might also break due to diverse sources of interference or packet collisions. We develop a statistical framework to distinguish between the mobility and interference or collision errors. With this framework, we are able to determine and analyze the lifetime distributions for both error types separately. We use this framework together with our measurements to validate two commonly used stochastic mobility models including the random waypoint and the random reference group mobility model. The results show that the distributions of the two stochastic mobility models match very closely the empirical link lifetime distribution. Copyright 2006 ACM.
A common multi-core pattern consists of processors communicating through shared, multi-banked on-chip memory. Two approaches exist: Interleaved address mapping, which spreads consecutive data over all banks, and conti...
详细信息
This paper analyzes the characteristics of a multi-hop 802.11b mobile ad hoc network. We present data gathered from a mobile network of 20 devices carried by test users over 5 days in an indoor environment. The data i...
详细信息
暂无评论