Sudden Death due to Diseases of the Adrenal Glands and Paraganglia

Coroners and pathologists commonly evaluate unexpected deaths due to diseases of the adrenal glands and paraganglia, which are, unfortunately, not rare in their totality. Although cardiac causes are the main cause of sudden death, endocrine conditions can produce sudden, unexpected deaths that need further investigation, especially in younger patients. This chapter focuses on the issue of sudden death due to diseases involving adrenal glands and paraganglia. The main causes of sudden death due to adrenal gland pathology will be examined, paying particular attention to the pathophysiology of sudden death, macroscopic and microscopic characteristics and their correlation with clinical features. These issues are of great interest, especially considering the clinical impact of sudden death and its rarity among patients with adrenal gland diseases. The forensic pathologist’s examination is extremely important in determining the cause of death and findings not clinically observable and can contribute to the improvement of the clinical and surgical approach in treating such patients

Dynamic power management for portable systems

Portable systems require long battery lifetime while still delivering high performance. Dynamic power management (DPM) policies trade off the performance for the power consumption at the system level in portable devices. In this work we present the time-indexed SMDP model (TISMDP) that we use to derive optimal policy for DPM in portable systems. TISMDP model is needed to handle the non-exponential user request interarrival times we observed in practice. We use our policy to control power consumption on three different devices: the SmartBadge portable device [18], the Sony Vaio laptop hard disk and WLAN card. Simulation results show large savings for all three devices when using our algorithm. In addition, we measured the power consumption and performance of our algorithm and compared it with other DPM algorithms for laptop hard disk and WLAN card. The algorithm based on our TISMDP model has 1.7 times less power consumption as compared to the default Windows timeout policy for the hard disk and three times less power consumption as compared to the default algorithm for the WLAN card

Abstract

low-power, operating system, application driven In this report we present an energy efficient implementation of a commercial-strength operating system (ECOS) running on a reallife hardware platform (HP SmartBadge IV). We integrate into the OS a power manager module that cooperates with the applications and power-aware device drivers through a set of APIs. The power manager makes decisions on power states of various system components, and sets processor clock frequency dynamically. We tested our RTOS implementation in single and multiple task environments. We used typical streaming multimedia applications that exploit wireless network and audio resources. Measurements obtained on MP3 audio decoder and other signal processing algorithms show that the whole system energy can be reduced by more than 50 % with no effect on performance when using our extensions to the operating system

Energy-Efficient Design of Battery-Powered Embedded Systems

Energy-efficient design of battery-powered systems demands optimizations in both hardware and software. We present a modular approach for enhancing instruction level simulators with cycle-accurate simulation of energy dissipation in embedded systems. Our methodology has tightly coupled component models thus making our approach more accurate. Performance and energy computed by our simulator are within a 5% tolerance of hardware measurements on the SmartBadge [2]. We show how the simulation methodology can be used for hardware design exploration aimed at enhancing the SmartBadge with realtime MPEG video feature. In addition, we present a profiler that relates energy consumption to the source code. Using the profiler we can quickly and easily redesign the MP3 audio decoder software to run in real time on the SmartBadge with low energy consumption. Performance increase of 92% and energy consumption decrease of 77% over the original executable specification have been achieved. Keywords--- low-power-design, system-level, performancetradeoffs, power-consumption-model I

Event-Driven Power Management of Portable Systems

The policy optimization problem for dynamic power management has received considerable attention in the recent past. We formulate policy optimization as a constrained optimization problem on continuous-time SemiMarkov decision processes (SMDP). SMDPs generalize the stochastic optimization approach based on discrete-time Markov decision processes (DTMDP) presented in the earlier work by relaxing two limiting assumptions. In SMDPs, decisions are made at each event occurrence instead of at each discrete time interval as in DTMDP, thus saving power and giving higher performance. In addition, SMDPs can have general inter-state transition time distributions, allowing for greater generality and accuracy in modeling reallife systems where transition times between power states are not geometrically distributed

Cycle-Accurate Simulation of Energy Consumption in Embedded Systems

This paper presents a methodology for cycle-accurate simulation of energy dissipation in embedded systems. The ARM Ltd. [1] instruction-level cycle-accurate simulator is extended with energy models for the processor, the L2 cache, the memory, the interconnect and the DC-DC converter. A SmartBadge, which can be seen as an embedded system consisting of StrongARM-1100 processor, memory and the DCDC converter, is used to evaluate the methodology with the Dhrystone benchmark. We compared performance and energy computed by our simulator with measurements in hardware and found them in agreement within a 5% tolerance. The simulation methodology was applied to design exploration for enhancing a SmartBadge with real-time MPEG feature

Dynamic Power Management for Portable Systems

Portable systems require long battery lifetime while still delivering high performance. Dynamic power management (DPM) policies trade off the performance for the power consumption at the system level in portable devices. In this work we present the time-indexed SMDP model (TISMDP) that we use to derive optimal policy for DPM in portable systems. TISMDP model is needed to handle the nonexponential user request interarrival times we observed in practice. We use our policy to control power consumption on three different devices: the SmartBadge portable device [18], the SonyVaio laptop hard disk and WLAN card. Simulation results show large savings for all three devices when using our algorithm. In addition, we measured the power consumption and performance of our algorithm and compared it with other DPM algorithms for laptop hard disk and WLAN card. The algorithm based on our TISMDP model has 1.7 times less power consumption as compared to the default Windows timeout policy for the hard disk and three times less power consumption as compared to the default algorithm for the WLAN card