Illinois Institute of Technology

About: Illinois Institute of Technology is a education organization based out in Chicago, Illinois, United States. It is known for research contribution in the topics: Electric power system & Wireless network. The organization has 10188 authors who have published 21062 publications receiving 554178 citations. The organization is also known as: IIT & Illinois Tech.

Efficacy of two behavioral treatment programs for comorbid geriatric insomnia

Abstract: Older adults with comorbid insomnia and medical illness have been excluded from behavioral treatment research, but recent evidence suggested that such treatments would be effective with this population. In this study, 38 older adults with comorbid insomnia were randomized to 1 of 3 conditions: classroom cognitive-behavioral treatment (CBT), home-based audio relaxation treatment (HART), or delayed-treatment control. Compared to the control group, the CBT group had significant changes in 5 of 7 self-report measures of sleep at the 4-month follow-up. The HART group obtained significant outcomes on 3 of 7 measures. Wrist actigraphy measures and secondary-outcome measures did not yield significant findings for either treatment. Clinically significant changes at follow-up were obtained for 54% of patients in CBT, 35% in HART, and 6% in the control group when treatment dropouts were included. Although not as effective as in-person CBT, home interventions may have utility as a first-line, low-cost treatment.

Power-Electronics-Enabled Autonomous Power Systems: Architecture and Technical Routes

Abstract: Power systems are going through a paradigm change from centralized generation to distributed generation and further on to smart grids. In this paper, it is shown that future power systems will be power electronics based, instead of electric machines based, with a huge number of incompatible players and that the fundamental challenge behind this paradigm change is how to make sure these players could work together and maintain system stability. Then, a lateral architecture based on the synchronization mechanism of synchronous machines (SM), which has underpinned the growth and operation of power systems for over 100 years, is proposed to unify the integration and interaction of these players with the grid by operating power electronic converters to behave like virtual synchronous machines (VSM), which are coined cyber synchronous machines (CSM) here. Thus, all the suppliers and the majority of loads can follow the same mechanism to regulate system stability. This paves the way for autonomous operation of future power systems. Moreover, two technical routes, one based on the synchronverter technology and the other based on the robust droop control technology, are proposed to implement the architecture. Real-time simulation results are presented to illustrate the operation of such a system.

The impact of blood shear rate on arterial thrombus formation

Abstract: The shear rate and corresponding shear stress have impacts on arterial thrombus formation. In particular, the effects of increasing concentration of platelets at the vessel wall and activation of platelets at this site increase the growth and stability of the thrombi which may result in a fatal narrowing of the arterial lumen. The efficacy of many antithrombotic agents is shear dependent as well. It is apparent that there is a need for a point-of-care device to rapidly monitor the risk for arterial thrombosis and to optimize antithrombotic therapy in vitro. The present review focuses on the essential role of shear rate on arterial thrombus formation in native human blood drawn directly from an antecubital vein.

Energy Efficient TDMA Sleep Scheduling in Wireless Sensor Networks

Abstract: Sleep scheduling is a widely used mechanism in wireless sensor networks (WSNs) to reduce the energy consumption since it can save the energy wastage caused by the idle listening state. In a traditional sleep scheduling, however, sensors have to start up numerous times in a period, and thus consume extra energy due to the state transitions. The objective of this paper is to design an energy efficient sleep scheduling for low data-rate WSNs, where sensors not only consume different amounts of energy in different states (transmit, receive, idle and sleep), but also consume energy for state transitions. We use TDMA as the MAC layer protocol, because it has the advantages of avoiding collisions, idle listening and overhearing. We first propose a novel interference-free TDMA sleep scheduling problem called contiguous link scheduling, which assigns sensors with consecutive time slots to reduce the frequency of state transitions. To tackle this problem, we then present efficient centralized and distributed algorithms that use time slots at most a constant factor of the optimum. The simulation studies corroborate the theoretical results, and show the efficiency of our proposed algorithms.

ZHT: A Light-Weight Reliable Persistent Dynamic Scalable Zero-Hop Distributed Hash Table

Abstract: This paper presents ZHT, a zero-hop distributed hash table, which has been tuned for the requirements of high-end computing systems. ZHT aims to be a building block for future distributed systems, such as parallel and distributed file systems, distributed job management systems, and parallel programming systems. The goals of ZHT are delivering high availability, good fault tolerance, high throughput, and low latencies, at extreme scales of millions of nodes. ZHT has some important properties, such as being light-weight, dynamically allowing nodes join and leave, fault tolerant through replication, persistent, scalable, and supporting unconventional operations such as append (providing lock-free concurrent key/value modifications) in addition to insert/lookup/remove. We have evaluated ZHT's performance under a variety of systems, ranging from a Linux cluster with 512-cores, to an IBM Blue Gene/P supercomputer with 160K-cores. Using micro-benchmarks, we scaled ZHT up to 32K-cores with latencies of only 1.1ms and 18M operations/sec throughput. This work provides three real systems that have integrated with ZHT, and evaluate them at modest scales. 1) ZHT was used in the FusionFS distributed file system to deliver distributed meta-data management at over 60K operations (e.g. file create) per second at 2K-core scales. 2) ZHT was used in the IStore, an information dispersal algorithm enabled distributed object storage system, to manage chunk locations, delivering more than 500 chunks/sec at 32-nodes scales. 3) ZHT was also used as a building block to MATRIX, a distributed job scheduling system, delivering 5000 jobs/sec throughputs at 2K-core scales. We compared ZHT against other distributed hash tables and key/value stores and found it offers superior performance for the features and portability it supports.