Search results

The European cycle route network Eurovelo: challenges and opportunities for sustainable tourism

Resource-Efficient Image Buffer Architecture for Neighborhood Processors

Neighborhood image processing operations on Field Programmable Gate Array (FPGA) are considered as memory intensive operations. A large memory bandwidth is required to transfer the required pixel data from external memory to the processing unit. On-chip image buffers are employed to reduce this data transfer rate. Conventional image buffers, implemented either by using FPGA logic resources or embedded memories are resource inefficient. They exhaust the limited FPGA resources quickly. Consequently, hardware implementation of neighborhood operations becomes expensive, and integrating them in resource constrained devices becomes unfeasible. This paper presents a resource efficient FPGA based on-chip buffer architecture. The proposed architecture utilizes full capacity of a single Xilinx BlockRAM (BRAM36 primitive) for storing multiple rows of input image. To get multiple pixels/clock in a user defined scan order, an efficient duty-cycle based memory accessing technique is coupled with a customized addressing circuitry. This accessing technique exploits switching capabilities of BRAM to read 4 pixels in a single clock cycle without degrading system frequency. The addressing circuitry provides multiple pixels/clock in any user defined scan order to implement a wide range of neighborhood operations. With the saving of 83% BRAM resources, the buffer architecture operates at 278 MHz on Xilinx Artix-7 FPGA with an efficiency of 1.3 clock/pixel. It is thus capable to fulfill real time image processing requirements for HD image resolution (1080 × 1920) @103 fcps.

Optimization of protocols using neuromuscular electrical stimulation for paralyzed lower-limb muscles to increase energy expenditure in people with spinal cord injury

OBJECTIVE: To evaluate if using surface neuromuscular electrical stimulation (NMES) for paralyzed lower-limb muscles results in an increase in energy expenditure and if the number of activated muscles and duty cycle affect the potential increase.DESIGN: Cross-sectional study.RESULTS: Energy expenditure during all NMES protocols was significantly higher than the condition without NMES (1.2 ± 0.2 kcal/min), with the highest increase (+ 51%; +0.7 kcal/min, 95% CI: 0.3 - 1.2) for the protocol with more muscles activated and the duty cycle with a shorter rest period. A significant decrease in muscle contraction size during NMES was found with a longer stimulation time, more muscles activated or the duty cycle with a shorter rest period.CONCLUSION: Using NMES for paralyzed lower-limb muscles can significantly increase the energy expenditure compared to sitting without NMES with the highest increase for the protocol with more muscles activated and the duty cycle with a shorter rest period. Muscle fatigue occurred significantly with the more intense NMES protocols which might cause a lower energy expenditure in a longer protocol. Future studies should further optimize the NMES parameters and investigate the long-term effects of NMES on weight management in people with SCI.

(re)CYCLE Limburg

This booklet holds a collection of drawings, maps, schemes, collages, artistic impressions etc. which were made by students during an intense design moment in the project (re)CYCLE Limburg, which took place in December 2016. Students of Built Environment, Facility Management, Social Work and Health & Care cooperated in making designs and developing strategies for urban renewal in Kerkrade West (Province of Limburg, the Netherlands). The study focused on the importance of qualitative and shared public spaces. The local community (inhabitants, shopkeepers, entrepreneurs, municipality, housing corporation) was actively engaged by sharing knowledge and information, ideas and opinions. These reflections are part of the Limburg Action Lab (part of the Smart Urban Redesign Research Centre). It engages in research by design on innovative and tactical interventions in public space, that might enhance the identity, sustainability and socio-spatial structure of neighbourhoods.

Prolonged electrical stimulation-induced gluteal and hamstring muscle activation and sitting pressure in spinal cord injury: Effect of duty cycle

Abstract—Pressure ulcers (PUs) are highly prevalent in people with spinal cord injury (SCI). Electrical stimulation (ES) activates muscles and might reduce risk factors. Our objectives were to study and compare the effects of two duty cycles during 3 h of ES-induced gluteal and hamstring activation on interface pressure distribution in sitting individuals with SCI and study the usability of a newly developed electrode garment (ES shorts). Ten individuals with SCI participated in this study, in which two ES protocols with different duty cycles (1:1 s vs 1:4 s on-off) were applied in counterbalanced order using a custom-made garment with built-in electrodes. Outcome variables included interface pressure of the ischial tuberosities (ITs) and pressure gradient. A questionnaire was used to determine usability of the ES shorts. In both protocols, ES caused a significant decrease in average IT pressure compared with rest (no ES); on average, 35% for protocol 1:4 and 13% for protocol 1:1. The ES on-off duty cycle of protocol 1:4 showed less muscle fatigue. In general, participants scored the usability of the ES shorts as satisfactory. In this study, the application of ES resulted in a significant decrease in IT pressure. The ES on-off duty cycle of 1:4 s is recommended because of the less fatiguing effect. ES of the hamstrings and gluteal muscles might be a promising method in preventing PUs, but further study is needed.

In Situ Assessment of Uplink Duty Cycles for 4G and 5G Wireless Communications

In this presented study, we measured in situ the uplink duty cycles of a smartphone for 5G NR and 4G LTE for a total of six use cases covering voice, video, and data applications. The duty cycles were assessed at ten positions near a 4G and 5G base-station site in Belgium. For Twitch, VoLTE, and WhatsApp, the duty cycles ranged between 4% and 22% in time, both for 4G and 5G. For 5G NR, these duty cycles resulted in a higher UL-allotted time due to time division duplexing at the 3.7 GHz frequency band. Ping showed median duty cycles of 2% for 5G NR and 50% for 4G LTE. FTP upload and iPerf resulted in duty cycles close to 100%.