474: lighting and thermal performance of innovative shading devices: new insights into their aesthetics and control in a Mediterranean climate

With a view towards minimising energy demand for cooling and artificial lighting in buildings, this paper evaluates innovative shading devices and how they can balance a generous degree of control mastering seasonal natural light with thermal gains in a typical Mediterranean climate such as Malta. The study evaluates the potential success (or failure) of such shading devices, from both their aesthetic and functional perspectives, as part of a passive design strategy adopted by the architect. Through environmental design and solar geometry, experimental simulations were generated in architectural science modelling software package Ecotect© developed by Andrew Marsh. Moreover a novel computer model termed Solar Control© was developed by the authors in order to assist architects at an early stage during design.peer-reviewe

BYU Passive Inspection CubeSats (PICS)

The BYU Passive Inspection CubeSat (PICS) is the first stage of a series of technology demonstration missions for spacecraft capable of performing inspection, maintenance and assembly on another spacecraft. PICS will demonstrate ultrafast booting and power-up operation of system electronics and the low-risk inspection of the exterior of a spacecraft by a passive, inexpensive flyaway probe. Two flight systems deployed simultaneously will enable the collection of image data from each other as well as the parent spacecraft. Both units include spherical imaging capability using a camera on each face of the 10 cm cube so that attitude control is not required, which simplifies the system

MoonWalker, a Lower Limb Exoskeleton able to Sustain Bodyweight using a Passive Force Balancer

Abstract-This paper presents MoonWalker, a lower limb exoskeleton able to sustain part of a user's bodyweight. This orthosis can be used for rehabilitation, to help people having weak legs, or to help those suffering from a broken leg, to walk. It can also be used as an assistive device helping people carrying heavy loads. Its main characteristic is that a passive force balancer provides the force to sustain bodyweight. An actuator is also required, but is used only to shift that force the same side as the leg in stance. Consequently, MoonWalker requires very low energy to work on flat terrains. That motor can provide also a part of the energy to climb stairs or slopes. We believe that this approach can help improving energetic autonomy of lower limb exoskeletons

VOLTAGE-CONTROLLED SMALL SIGNAL ANALYSIS OF REAL SPACE TRANSFER TRANSISTOR

The research of determining the small signal equivalent circuit of the real space transfer (RST) transistor is investigated in this work. We propose a voltage-controlled mode model, called parameter extraction, to describe the performance of RST transistors at high frequency range. Besides, we also employ the value-determined model to simulate the microwave characteristics of RST and the theoretical and experimental results are compared. The influence of variables of RF performance is analyzed and theoretical results show that the cut-off frequency ( f T ) is mainly affected by the leakage resistances and the dimension of metal contact, but the maximum available gain frequency, f max , is dependent on contact resistances

INSUFFICIENCIES OF THE SINGLE EXPONENTIAL MODEL AND EFFICIENCY OF THE DOUBLE EXPONENTIAL MODEL IN TIlE OPTIMIZATION OF SOLAR CELLS EFFICIENCY

Single and double exponential models are confronted to determine the most adapted model for optimization of solar cells efficiency. It is shown that the single exponential model (SEM) presents some insufficiencies for efficiency optimization. The interest of the double exponential model to optimize the efficiency and to achieve an adequate simulation of the operation of solar cells is demonstrated by means of I-V characteristics plotting

FLAT TYPE THICK FILM INDUCTIVE SENSORS

Two thick film flat-type inductive sensors are described and tested for distance and profile measurement. The first one is a single-layer spiral while the second one is a multi-layer structure consisting of ten spirals one over the other. The paper describes their geometric configurations together with their simulated magnetic fields and it reports the results from the characterization test i.e. the series-equivalent circuit parameters, the sensitivity and the cross-sensitivity to temperature. An experimental analysis of the sensitivity suggests that optimized values are obtained by an appropriate choice of the working frequency. The sensors are shielded against e.m. noise coming from the nonsensitive area. Moreover, two sensors have been tested in the laboratory using the single layer as a distance sensor and the multi-layer as a transducer for the measurement of a metallic object profile. The results of the tests show a maximum sensitivity of 14 mV=mm and a resolution of 0.6 mm for the single layer, while the multi layer one reconstructs the profile with an axial resolution of a few microns and a lateral resolution better than 200 mm

Occupant satisfaction in post-refurbishment of historic buildings : baroque case studies in Valletta, Malta

This paper evaluates occupants’ subjective response to controlled architectural interventions in listed historic buildings, as part of a comprehensive plan to restore, rehabilitate and re-use the edifice. The overall strategy was to monitor a series of historic buildings, which typically represent the same period, namely 16th century architecture, depicting the Baroque period in Malta’s World Heritage Capital, Valletta. Such buildings often had discrete traditional physical features, such as ventilation stacks through their thick massive walls and an open courtyard, generating the typical introvert planning. These assisted the acclimatisation of their indoor spaces. Interventions were limited to exposing their thermal mass and re-activating the original features. The buildings were partially assessed for their thermal performance through a post-occupancy survey (POS), based on subjective evidence. Questionnaires and structured interviews were conducted with office staff, two years after entering the commissioned refurbished buildings. Results indicated that the revival of modest passive design solutions was effective in attaining comfort levels today, thus reducing the dependence on energy guzzling modern environmental control systems. This suggests that such featurerevealing interventions can be easily adapted to other similar historic buildings offered for refurbishment, thus achieving energy efficiency all round, also reducing their overall carbon footprint.peer-reviewe

DEPENDENCE ON THE PARTIAL PRESSURE OF OXYGEN ON THE SHIFT IN THE ENERGY BAND-GAP OF CdO THIN FILMS IN THE VISIBLE REGION

In this paper, the dependence on the partial pressure of oxygen of the shift in the energy band-gap of CdO thin films for the visible region is investigated from the theoretical point of view on an experimental basis. In our analysis, the role played by the dependence of the carrier density upon the above pressure is emphasized

SIMILARITY CRITERIA OF EHF PHYSICAL MODEL OF LONG DISTANCE TRANSMISSION LINE WITH PLATE PHASES

Carson's equations for computation o

SOME INVESTIGATIONS ON THE ANISOTROPY OF THE CHEMICAL ETCHING OF (h k 0) AND (h h l) SILICON PLATES IN A NaOH 35% SOLUTION. PART III: DETERMINATION OF A DATABASE FOR THE SIMULATOR TENSOSIM AND PREDICTION OF 2D ETCHING SHAPES

The simulation of 2D etching shapes such as surface profiles and out-of-roundness profiles related to various (h k 0) and (h h l) silicon plates or cross-sections is studied. The theoretical basis of the simulation is presented. The database for the simulator TENSOSIM is determined from a systematic analysis of experimental 2D etching shapes. Emphasis is placed on difficulties encountered in the determination procedure. Theoretical 2D etching shapes are compared with experimental shapes. A correlation between polar plots of the dissolution slowness and corresponding theoretical shapes is established. So we can conclude that the accuracy of the proposed database is sufficient for the simulation of 2D etching shapes