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The Ottoman cultural legacy in Algeria is made up of a diverse range of architectural structures. The Algerian government strategy in connection with the Ottoman old buildings is to restore them into museums. This study will attempt to present a contrastive analysis between two old palaces being under restoration (refurbishment), and the goal is to propose a museum route by calculating the ambiance aimed at circulating the rooms by visitors.

The authors analyzed the architectural components of the various entities by observing in situ and taking measurements for a single case study to get a sense of the results for the mid-season (spring and fall). The configuration was next evaluated by modeling the space syntax and combining it with a simulation of daylight luminance, for the period when the authors could not make measurements on-site. The ultimate goal is to combine these findings to suggest the ideal in-route for the future museum.

This research allowed the authors to propose a museum itinerary adapted to the new vocation of the palaces, which considers the daylight as an element of composition in the spaces of circulation.

The paper proposes solutions to a flow management problem encountered in several similar palaces converted into museums.

The study aims to raise questions on the museum, and to preserve such heritage from neglect by giving it a new life more adapted to the needs of the Algerian society.

The authors believe that this contribution will be a creative solution for issues related to the operation of palaces that have been converted into museums.

One major problem in the lighting industry is the thermal management of the devices. Handling of thermal resistance from solder point to the ambiance of the light-emitting diode (LED) package is linked to the external thermal management that includes a selection of the cooling mode, design of heatsink/substrate and thermal interface material (TIM). Among the significant factors that increase the light output of the of the LED system are efficient substrate and TIM. In this work, the influence of TIM on the luminous flux performance of commercial indium gallium aluminium phosphide (InGaAlP) low-power (LP) LEDs was investigated.

One batch of LEDs was mounted directly onto substrates which were glass-reinforced epoxy (FR4) and aluminium-based metal-core printed circuit boards (MCPCBs) with a dielectric layer of different thermal conductivities. Another batch of LEDs was prepared in a similar way, but a layer of TIM was embedded between the LED package and substrate. The TIMs were thermally conductive epoxy (TCE) and thermally conductive adhesive (TCA). The LED parameters were measured by using the integrated system of thermal transient tester (T3Ster) and thermal-radiometric characterization of LEDs at various input currents.

With the employment of TIM, the authors found that the LED’s maximum luminous flux was significantly higher than the value mentioned in the LED datasheet, and that a significant reduction in thermal resistance and junction temperature was revealed. The results showed that for a system with low thermal resistance, the maximum luminous flux appeared to occur at a higher power level. It was found that the maximum luminous flux was 24.10, 28.40 and 36.00 lm for the LEDs mounted on the FR4 and two MCPCBs, respectively. After TCA application on the LEDs, the maximum luminous flux values were 32.70, 36.60 and 37.60 lm for the FR4 and MCPCBs, respectively. Moreover, the findings demonstrated that the performance of the LED mounted on the FR4 substrate was more affected by the employment of the TIM than that of MCPCBs.

One of the major problems in the lighting industry is the thermal management of the device. In many low-power LED applications, the air gap between the two solder pads is not filled up. Heat flow is restricted by the air gap leading to thermal build-up and higher thermal resistance resulting in lower maximum luminous flux. Among the significant factors that increase the light output of the LED system are efficient substrate and TIM.

The findings in this work can be used as a method to improve thermal management of LP LEDs by applying thermal interface materials that can offer more efficient and brighter LP LEDs. Using aluminium-based substrates can also offer similar benefits.

Users of LP LEDs can benefit from the findings in this work. Brighter automotive lighting (signalling and backlighting) can be achieved, and better automotive lighting can offer better safety for the people on the street, especially during raining and foggy weather. User can also use a lower LED power rating to achieve similar brightness level with LED with higher power rating.

Better thermal management of commercial LP LEDs was achieved with the employment of thermal interface materials resulting in lower thermal resistance, lower junction temperature and brighter LEDs.

Thermal management of high-power (HP) light-emitting diodes (LEDs) is an essential issue. Junction temperature (T_J) and thermal resistance (R_th) are critical parameters in evaluating LEDs thermal management and reliability. The purpose of this paper is to study thermal and optical characteristics of ThinGaN (UX:3) white LED mounted on SinkPAD by three types of solder paste (SP): No-Clean SAC305 (SP1), Water-Washable SAC305 (SP2) and No-Clean Sn42/Bi57.6/Ag0.4 (SP3).

Thermal transient tester (T3Ster) machine is used to determine T_J and total thermal resistance (R_th–JA). In addition, the LED’s optical properties are measured via thermal and radiometric characterization of power LEDs (TeraLED) system. The LED is mounted on SinkPAD using SP1, SP2 and SP3 by stencil printing to control a thickness of SP and reflow soldering oven to minimize the number of voids. The LED with SP1, SP2 and SP3 is tested at various input currents and ambient temperatures.

The results indicate that at high input current, which equals to 1,200 mA, R_th–JA and T_J, respectively, are reduced by 30 and 17 per cent between SP1 and SP2. At same current value, R_th–JA and T_J are minimized by 42 and 25 per cent between SP1 and SP3, respectively. In addition, at an ambient temperature of 85°C, R_th–JA and T_J are decreased by 34 and 7 per cent between SP1 and SP2, respectively. Similarly, the reduction in R_th–JA and T_J between SP1 and SP3 is 44 and 10 per cent, respectively. Luminous flux, luminous efficacy and color shift of the LED with the three types of SPs are compared and discussed. It is found that the SP1 improves the chromatic properties of the LED by increasing the overall light efficiency and decreasing the color shift.

Thermal and optical performance of ThinGaN LEDs mounted on SinkPAD via three types of SPs is compared. This investigation can assist the research on thermal management of HP ThinGaN-based LEDs.

The purpose of this paper is to investigate how electronic components can be utilized and integrated into polymeric optical fibre (POF) textiles to refine the design aesthetic, tactile quality and initiate the interaction of textiles with the users; and to study the design process of interactive products by using a novel design process model.

Fashion and textile design methods, textile technology are used in combination with modern technologies such as laser engraving, sensing, short-distance communication technology, throughout the entire process of development of interactive photonics creations.

The results of evaluation indicate that the engineered prototypes can enhance the interactive function of interior furnishing. The usability of interactive POF cushions is optimized by innovative design methods considering both design and technology.

This research explores to combine knowledge from different disciplines, including textile, electronics, sensor and laser to create interactive soft furnishings. The inter-disciplinary research provides a new perspective on how POF fabric can be utilized as a new media to change the way people interact with their living surroundings. The interior soft furnishings are no longer unresponsive to people, but can react to them, adapt to their behaviors, change color according to their preferences and therefore merge into our daily life. The developed prototypes reshape interior soft furnishing, and therefore have both theoretical and practical significance.

Proper thermal management is a key to improve the efficiency and reliability of light-emitting diodes (LEDs). This paper aims to report the influence of applying thermally conductive materials on thermal performance of indium gallium aluminum phosphide (InGaAlP)-based thin-film surface-mounted device (SMD) LED.

The LED thermal and optical parameters were determined using the combination of thermal transient tester (T3Ster) and thermal and radiometric characterization of power LEDs (TeraLED) instruments. The LED was mounted on FR4, 2W and 5W aluminum (Al) package substrates. Measurements were carried out by setting different boundary conditions: air between LED package and substrate and using thermally conductive epoxy (TIM A) and adhesive (TIM B) of thermal conductivity 1.67 and 1.78 W/mK, respectively.

For LED mounted on FR4 package, the total real thermal resistance is improved because of TIM B by 6 and 9 per cent at 50 and 100 mA, respectively. Likewise, the relative decrease in total thermal resistance of LED on 2W Al package is about 9 and 11 per cent. As well, for LED mounted on 5W Al package, the total real thermal resistance is reduced by 2 and 4 per cent.

No much work can be found in the literature on thermal interface material effects on thermal performance of low-power SMD LED. This work can assist in thermal management of low-power LEDs.

An indoor office space should not only provide adequate illuminance on horizontal planes but also cater to the physiological and psychological requirements of the occupants. This paper aims to describe a lighting simulation-based work conducted in Kolkata, India which modeled an indoor office to investigate the effects of variation in room surface reflectance combinations on user perception, mean room surface exitance (MRSE), average horizontal illuminance and overall uniformity of horizontal illuminance.

A fluorescent illumination system–based office space was modeled and retrofitted with tubular LED lamps in DIALux. Simulations were conducted for 16 different room surface reflectance combinations and a five-point Likert scale-type survey questionnaire was formulated to conduct a survey with 32 test subjects to assess the subjective preferability of each resultant light scene.

Simulation results demonstrate that the relationship between average horizontal illuminance and MRSE as well as between average horizontal illuminance and overall uniformity of horizontal illuminance, was statistically significant (p < 0.001). In the conducted survey, the resultant light scene arising out of the reflectance combination of wall:ceiling:floor = 60%:90%:20% was the most well-received one with 187 convinced agreements (“agree” and “strongly agree” responses).

This work found strong linear correlation between average horizontal illuminance and MRSE and between average horizontal illuminance and overall uniformity. A five-point Likert scale-type survey questionnaire with seven questions was formulated and validated with 32 test subjects (Cronbach’s alpha > 0.9295), which showed that the wall:ceiling:floor reflectance combination of 60%:90%:20% was the most favored choice.

The responsibilities of the employer/facilities manager in today′s “commercial” world are extensive when considering the wellbeing of staff and the economic working of the office/building. One element of this tangled web is lighting. The recent publication by the Chartered Institute of Building Services Engineers (the professional body), Lighting Guide No. LG7, Office Lighting (1993), is an invaluable compendium in guiding professional “lighters” and the non‐expert in design standards. The guide is particularly useful not only in considering good practice, but also in identifying subjects where the employer is possibly vulnerable with respect to recent EEC legislation and health and safety requirements for satisfactory VDU operations working; and emergency lighting, among others. Examines the contents of LG7, highlighting areas of particular interest and likely concerns to the inquisitive facilities manager.

Compiled by K.G.B. Bakewell covering the following journals published by MCB University Press: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.

Index by subjects, compiled by K.G.B. Bakewell covering the following journals: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.

Compiled by K.G.B. Bakewell covering the following journals published by MCB University Press: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.