Adaptive Quality of Service Control in Distributed Real-Time Embedded Systems

An increasing number of distributed real-time embedded systems face the critical challenge of providing Quality of Service (QoS) guarantees in open and unpredictable environments. For example, such systems often need to enforce CPU utilization bounds on multiple processors in order to avoid overload and meet end-to-end dead-lines, even when task execution times deviate significantly from their estimated values or change dynamically at run-time. This dissertation presents an adaptive QoS control framework which includes a set of control design methodologies to provide robust QoS assurance for systems at different scales. To demonstrate its effectiveness, we have applied the framework to the end-to-end CPU utilization control problem for a common class of distributed real-time embedded systems with end-to-end tasks. We formulate the utilization control problem as a constrained multi-input-multi-output control model. We then present a centralized control algorithm for small or medium size systems, and a decentralized control algorithm for large-scale systems. Both algorithms are designed systematically based on model predictive control theory to dynamically enforce desired utilizations. We also introduce novel task allocation algorithms to ensure that the system is controllable and feasible for utilization control. Furthermore, we integrate our control algorithms with fault-tolerance mechanisms as an effective way to develop robust middleware systems, which maintain both system reliability and real-time performance even when the system is in face of malicious external resource contentions and permanent processor failures. Both control analysis and extensive experiments demonstrate that our control algorithms and middleware systems can achieve robust utilization guarantees. The control framework has also been successfully applied to other distributed real-time applications such as end-to-end delay control in real-time image transmission. Our results show that adaptive QoS control middleware is a step towards self-managing, self-healing and self-tuning distributed computing platform

Political Legitimacy Under the Sociology of Law: Based on the Evolution of Political Legitimacy in the West

The concept of legitimacy changes with time and locations. This article concludes that the political legitimacy under the sociology of law is consistent with the degree of social equality and justice behind the scene by comparing the political legitimacy under the sociology of law during the time of German scholar Max Weber and American scholars Seymour Lipset and John Rawls. Through comparisons between the industrial and post-industrial societies, it is found that the interpretation of political legitimacy is heavily based on the needs of social development at that time, evolving from the legitimacy of individual actions, procedural legitimacy, and lastly, substantive legitimacy

Efficient Wideband DoA Estimation with a Robust Iterative Method for Uniform Circular Arrays

Direction-of-arrival (DoA) is a critical parameter in wireless channel estimation. With the ever-increasing requirement of high data rate and ubiquitous devices in wireless communication systems, effective wideband DoA estimation is desirable. In this paper, an iterative coherent signal-subspace method including three main steps in each iteration is proposed for wideband two-dimensional (2D) DoA estimation with a uniform circular array. The first step selects partial frequency points for the subsequent focusing process. The second step performs the focusing process, where the angle intervals are designed to generate focusing matrices with robustness, and the signal-subspaces at the selected frequency points are focused into a reference frequency. The third step estimates DoAs with the multiple signal classification (MUSIC) algorithm, where the range of the MUSIC spatial spectrum is constrained by the aforementioned angle intervals. The key parameters of the proposed method in the current iteration are adjusted based on the estimation results in the previous iterations. Besides, the Cram\'er-Rao bound of the investigated scenario of DoA estimation is derived as a performance benchmark, based on which the guidelines for practical application are provided. The simulation results indicate the proposed method enjoys better estimation performance and preferable efficiency when compared with the benchmark methods

Deciding Fast and Slow in Risk Decision Making: An Experimental Study

The current study presents findings of an experiment. Response time was used to investigate fast deciders’ (FD) and slow deciders’ (SD) behavioral differences. SDs were found to be more cognitive than FDs and this could induce an increase in average response time. Both FDs and SDs showed aversion to extreme options, but they behaved differently with option ‘S’ being “safer” among groups. Moreover, FDs responded more instinctively to negative feedbacks

DEUCON: Distributed End-to-End Utilization Control for Real-Time Systems

This paper presents the Distributed End-to-end Utiization CONtrol (DEUCON) algorithm. DEUCON can dynamically enforce desired CPU utilizations on all processors in a dis-tributed real-time system despite uncertainties in the system workload. In contrast to earlier centralized control schemes, DEUCON is a distributed control algorithm that is system-atically designed based on the Distributed Model Predictive Control theory. We decompose the global multi-processor utilization control problem into a set of localized subprob-lems, and design a peer-to-peer control structure where each local controller only needs to coordinate with a small number of neighbor processors. DEUCON can provide utilization guarantees similar to a centralized control algorithm, while significantly reducing the per-controller run-time overhead in terms of both computation and communication. Further-more, it can tolerate considerable network delay and indi-vidual processor failures. Consequently, DEUCON can pro-vide scalable and robust utilization control services for large distributed real-time systems that operate in unpredictable environments

Optimatization of sample points for monitoring arable land quality by simulated annealing while considering spatial variations

This presentation was given as part of the GIS Day@KU symposium on November 16, 2016. For more information about GIS Day@KU activities, please see http://gis.ku.edu/gisday/2016/.Arable land is the basis of food production, the most valuable input in agricultural production, and an important factor in sustainable agricultural development and national food security. In China, the reduction and degradation of arable land due to industrialization and urbanization has gradually emerged as one of the most prominen challenges. In this context, the long-term dynamic monitoring of arable land quality becomes important for protecting arable land resources. However, little consideration has been given to optimizing sample points number and layout in previous monitoring studies on arable land quality. When considering the optimization of sample points, various strategies are needed, depending on the indicators. In addition, the distributio of soil properties displays spatial variations. However, existing sampling studies have paid little attention to spatial variations during scenarios with multiple indicators.Therefore, it is necessary to further investigate how to improve the efficiency and accuracy of arable land quality monitoring and evaluation by optimizing the number and layout of sample points when there are spatial variations in multiple indicators.Platinum Sponsors: KU Department of Geography and Atmospheric Science. Gold Sponsors: Enertech, KU Environmental Studies Program, KU Libraries. Silver Sponsors: Douglas County, Kansas, KansasView, State of Kansas Data Access & Support Center (DASC) and the KU Center for Global and International Studies

REGULATION OF HYPOTHALAMIC POMC EXPRESSION BY MECP2 AND ITS CONTRIBUTION TO LEPTIN RESISTANCE

Ph.DDOCTOR OF PHILOSOPH

Decomposing the Growth of US Wine Exports to China into Scale, Competitive, and Second-order Effects

The study aims at investigating the reason for the growth of US wine exports to China through utilizing CMS (Constant Market Share Analysis) model decomposed into three effects: scale, competitive and second-order effect. The result shows that the increasing demand of Chinese market is the key factor for the growth of US wine exports to China; at the same time, it also indicates that the product competitiveness of US wine is declining, while market distribution channels are lacking. The phenomenon of the increase of Chinese market for importing American wine can be attributed to the growing Chinese wine market, the growth of economy in China and the increasing income of Chinese people, as well as the trade policy after China joining in WTO

Shear dispersion in the thermocline and the saline intrusion

Over the mid-Atlantic shelf of the North America, there is a pronounced shoreward intrusion of the saltier slope water along the seasonal thermocline, whose genesis remains unexplained. Taking note of the observed broad-band baroclinic motion, we postulate that it may propel the saline intrusion via the shear dispersion. Through an analytical model, we first examine the shear-induced isopycnal diffusivity ("shear diffusivity" for short) associated with the monochromatic forcing, which underscores its varied even anti-diffusive short-term behavior and the ineffectiveness of the internal tides in driving the shear dispersion. We then derive the spectral representation of the long-term "canonical" shear diffusivity, which is found to be the baroclinic power band-passed by a diffusivity window in the log-frequency space. Since the baroclinic power spectrum typically plateaus in the low-frequency band spanned by the diffusivity window, canonical shear diffusivity is simply 1/8 of this low-frequency plateau — independent of the uncertain diapycnal diffusivity. Applied to the mid-Atlantic shelf, this canonical shear diffusivity is about 20 m2 s−1, which is sufficient to account for the observed tracer dispersion or saline intrusion in the thermocline