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In the paper, an improved link adaptation scheme is proposed for theWiMedia MB-OFDM UWB system, in which quality of service (QoS) support is provided. The proposed scheme consists of three functional blocks: link quality indicator (LQI) calculator, frame error rate (FER)estimator, and transmitter (TX) parameter selector. Instead of using the average receive SNR (ASNR) as LQI, a new LQI metric is definedbased on a union bound analysis to capture the effects of both pathloss and frequency selectivity of an instantaneous UWB channel. Howto calculate LQI for each rate mode is investigated by analyzing the distribution of soft bit information. With the calculated LQI, theFER performance of each rate mode can be accurately estimated witha look-up table method, which is suitable for practical implementation. Using the estimated FERs, TX parameter selector can optimize TXrate mode to improve the communication throughput under QoS constraints. It is shown the proposed scheme can significantly improve the throughput while maintaining the required QoS compared to conventional ASNR based link adaptation schemes.

Lighting is a major part of energy consumption in buildings. Lighting systems will thus be one of the important component systems of a smart grid for dynamic load management services like demand response.In the scenario considered in this paper, under a demand response request, lighting systems in a building react by executing dimming control based on their load shedding flexibilities. Load shedding flexibility reflects the amount of power reduction that can be achievedby an individual controller without violating minimum illumination requirements of occupants in that area. We consider different methodsfor distributing load reduction across multiple controllers employing their respective load shedding flexibilities.

In this paper, we study the transmission strategy in a two-way relaychannel. In particular, we propose a new class of log_M1 (M_2)-MA (multi-access) block relay protocols where an M_1-ary modulation is used in the MA phase, and an M_2-ary in the broadcast phase. Lower-order (e.g., BPSK) and higher-order (e.g., 16-QAM, 32-PSK)modulations are used respectively for the multi-access phase and thebroadcast phase, in contrast to the conventional method of using the same modulation type (of either higher or lower order) throughout.To achieve this, the relay buffers the received symbols from consecutive multi-access phases and performs signal combining in conjunction with the decode-and-forward protocol. We derive the theoretical performance bounds for the Rayleigh fading channels and closed formsfor the AWGN channels. Numerical results confirm the advantages of the proposed scheme with an improved throughput in lower signal-to-noise ratio range.

A Simultaneous Non-contrast Angiography and intraPlaque hemorrhage (SNAP) MR imaging technique was proposed to detect both luminal stenosis and hemorrhage in atherosclerosis patients in a single scan. 13patients with diagnosed carotid atherosclerotic plaque were recruited after informed consent. All scans were performed on a 3T MR imaging system with SNAP, 2D time-of-flight (TOF) and magnetization-prepared 3D rapid acquisition gradient echo (MP-RAGE) sequences. The SNAPsequence utilized a phase sensitive acquisition, and was designed toprovide positive signals corresponding to intraplaque hemorrhage (IPH) and negative signals corresponding to lumen. SNAP images were compared to TOF images to validate lumen area measurements using linear mixed models and the intraclass correlation coefficient (ICC). IPHidentification accuracy was evaluated by comparing to MP-RAGE images using Cohen’s Kappa. Diagnostic quality SNAP images were generatedfrom all subjects. Quantitatively, the lumen area measurements by SNAP were strongly correlated (ICC=0.96, p<0.001) with those measuredby TOF. For IPH detection, strong agreement (&#954;=0.82, p<0.001)was also identified between SNAP and MP-RAGE images. The SNAP technique was proposed and validated to reliably detect in a single acquisition both luminal size and intraplaque hemorrhage in the patients with carotid atherosclerosis.

Medical Body Area Network (MBAN) technology provides a promising solution to improve patient care outcomes and lower healthcare costs. However, the current spectrum allocation cannot cater to increasing MBAN applications. Therefore, U.S., as well as other regions, have already been considering allocating a new spectrum for MBAN applications. In this paper we study a joint MBAN regulation proposal developed by Philips Healthcare, GE Healthcare, and AFTRCC that was recently presented to the FCC for the U.S. MBAN spectrum regulation. A brief summary of the joint proposal is firstly presented. Then the technical rationale behind the proposed parameters, such as frequency band selection, emission bandwidth limit, and transmission power limit, is discussed in detail. Link budget analysis and MBAN coexistencesimulations are given to demonstrate that the proposed solution canaddress the requirements of MBAN application.

GSD1a, the most prevalent type among the glycogen storage disease families, is caused by an inherited glycogen-6-phosphatase gene defectresulting in an impaired glycogen to glucose conversion pathway. Strict dietary management continues to be the only treatment for GSD1apatients. Recently, the advent of targeted ultrasound mediated delivery (USMD) of pDNA to the liver of GSD1a patients in conjunction with microbubbles may provide an alternative treatment option. As thesuccess of USMD of agents is largely dependent on the accessibilityof the targeted tissue by the ultrasound beam, there is a need to quantitatively determine this parameter. For this reason, this study focused on determining the acoustically accessible liver volume in GSD1a patients using transducer models of various apertures and focallengths using suitable CT and MRI datasets, following a geometry-driven approach. Results show that GSD1a patients generally have a larger acoustic accessible liver volume compared to a normal patient group for a given transducer geometry, and that transducers with a smaller aperture and longer focal length would be better suited for these applications. This data is a necessary initial design criterion for ultrasound mediated delivery systems for liver applications in general, and USMD pDNA delivery systems to the liver for GSD1a patientsin particular.

Glycogen storage disease type Ia (GSDIa) is caused by an inherited single-gene defect resulting in an impaired glycogen to glucose conversion pathway. Targeted ultrasound mediated delivery (USMD) of plasmid DNA to liver in conjunction with microbubbles may provide a potential treatment for GSDIa patients. As the success of USMD treatmentsis largely dependent on the accessibility of the targeted tissue bythe focused ultrasound beam, this study presents a quantitative approach to determine the acoustically accessible liver volume in GSDIapatients. Models of focused ultrasound beam profiles for transducers of varying aperture and focal lengths were applied to abdomen models reconstructed from suitable CT and MRI images. Transducer manipulations (simulating USMD treatment procedures) were implemented via transducer translations and 2D rotations with the intent of targetingand exposing the entire liver to ultrasound. Results indicate thatacoustically accessible liver volumes can be as large as 60% of theentire liver volume for GSDIa patients and on average 3 times largercompared to a normal group due to GSDIa patients’ increased liver size. Detailed descriptions of the evaluation algorithm, transducer-and abdomen models will be presented, together with implications forUSMD treatments of GSDIa patients and transducer designs for USMD applications.

Providing the right amount of light where and when it is needed is an opportunity to transform today’s cities into smart and livable urban spaces. New technologies are being introduced, such are adaptivecontrols and outdoor lighting networks, which can deliver energy andcost savings through adaptive lighting and streamlined maintenance.However, the full market potential for such systems has not been achieved. A number of issues have been hampering the market, from lackof clarity in adaptive lighting regulations, to system interoperability, cost and complexity issues. Standards and recommended practices that drive regulation on adaptive lighting are paramount to clearing the way to large scale deployment of intelligent and energy efficient lighting. Existing recommended practices do not explicitly address adaptive lighting requirements. In the area of communication technologies, the lighting industry has been trying to leverage existing standards, such as Internet protocols (TCP/UDP, IP) and connectivity standards (wireless and power line). However, the diversity of approaches in applying them has resulted in incompatible solutions atmultiple levels. On the other hand, it should be recognized that thetotal solution typically requires customizations to address problems beyond what is defined in existing connectivity standards. Therefore, there is a clear need for a balanced approach where standards can be developed to bring immediate value to customers by leveraging mature technologies, while leaving room for innovation.