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This study aims to provide a flexible and cost-effective solution of 3D heterogeneous integration for applications such as micro-electro-mechanical system (MEMS) applications and smart sensor systems.

A novel 3D system-in-package (SiP) based on stacked silicon submount technology was successfully developed and well-demonstrated by the fabrication and assembly process of a selected smart lighting module.

The stacked module consists of multiple layers of silicon submounts which can be designed and fabricated in parallel. The bonding and interconnecting process is quite simple and does not require complicated equipment. The 3D stacking design offers higher silicon efficiency and miniaturized package form factor. The submount wafer can be assembled and tested at the wafer level, thus reducing the cost and improving the yield.

The embedding design presented in this paper is applicable for modules with limited number of passives. When it comes to cases with more passive devices, new process needs to be developed to achieve fast, inexpensive and reliable assembly.

The presented 3D SiP design is novel for applications such as smart lighting, Internet of Things, MEMS systems, etc.

Properly planned road illumination systems are collectively a public wealth and the commissioning of such systems may require extensive planning, simulation and testing. The purpose of this simulative work is to offer a simple approach to facilitate luminance-based road lighting calculations that can be easier to comprehend and apply to practical designing problems when compared to complex multi-objective algorithms and other convoluted simulative techniques.

Road illumination systems were photometrically simulated with a created model in a validated software platform for specified system design configurations involving high-pressure sodium (HPS) and light-emitting diode (LED) luminaires. Multiple regression analyses were conducted with the simulatively obtained data set to propound a linear model of estimating average luminance, overall uniformity of luminance and energy efficiency of lighting installations, and the simulatively obtained data set was used to explore luminaire power–road surface average luminance characteristics for common geometric design configurations involving HPS and LED luminaires, and four categories of road surfaces.

The six linear equations of the propounded linear model were found to be well-fitted with their corresponding observation sets. Moreover, it was found that the luminaire power–road surface average luminance characteristics were well-fitted with linear trendlines and the increment in road surface average luminance level per watt increment of luminaire power was marginally higher for LEDs.

This neoteric approach of estimating road surface luminance parameters and energy efficiency of lighting installations, and the compendia of luminaire power–road surface average luminance characteristics offer new insights that can prove to be very useful for practical purposes.

The purpose of this paper is to use a series of disruptive innovations in the 150‐year history of the US lighting industry to test whether two key innovation management theories retain their explanatory power as market structures change.

Historical case studies of four successive disruptive lighting innovations are used: incandescent light bulbs, fluorescent light bulbs, compact fluorescent light bulbs (CFBs) and light emitting diodes (LEDs). Descriptions of each innovation include the new technologies, the evolving market structures, and how the innovating companies managed their risks during the transitions.

This paper finds that two contemporary theories on absorptive capacity and disruptive innovations retain validity and remain broadly applicable even as market structures change overtime from oligopoly and cartel to free market competition.

By juxtaposing historic incandescent and fluorescent bulb innovations in constrained market conditions with modern CFB and LED innovations in free market conditions, this paper expands understanding of the lighting history to include the past two decades. It also expands the applicability of innovation theories by showing that they apply to various and changing market structures.

An interdisciplinary body of literature has focused on the role of lighting in mitigating patient and employee stress and error-producing conditions in hospital settings. The purpose of this study is to explore how a new circadian lighting system installed in a small pharmacy unit with no penetration of natural light is experienced by staff. Psychosocial variables, such as affective organizational commitment, perceived productivity, well-being, and satisfaction with the physical work environment, were measured to further a line of inquiry that may help facilities managers and hospital administrators make optimal choices when purchasing lighting and commissioning retrofits.

Post-occupancy evaluation; mixed methods survey design.

While affective organizational commitment, perceived productivity, well-being and satisfaction with the physical work environment were experienced, to some extent, by employees, low average responses about whether the setting had improved, as the circadian lighting had been installed suggest that the retrofit did not affect them as positively as expected. Counter to the intention of the installation, participants did not perceive the circadian lighting as having strongly improved their levels of stress, concentration, mood or fatigue at work.

More research on simulated daylighting should be done to optimize occupant responses to lighting retrofits in hospitals. This case study supports recommendations to measure relevant psychosocial variables before and after a design change. Similarly, sized units within hospitals and health care facilities that possess analogous dimensions and design constraints concerning a lack of daylight penetration will benefit from this study’s mixed methods, results and interpretations.

This chapter examines what the hospitality sector can do to reduce its own carbon footprint as well as that of its guests. In particular, it addresses the issue of lighting and certain consumer-oriented products used in hotels and other public places by examining solutions designed to reduce carbon emissions, cut operating costs, and create a pleasant ambience. These moves toward a low carbon experience for both business and leisure tourists are set against the stipulations of current legislation, barriers to change, as well as international initiatives to make travel greener.

Thermal behavior of light-emitting diode (LED) device under different operating conditions must be known to enhance its reliability and efficiency in various applications. The purpose of this study is to report the influence of input current and ambient temperature on thermal resistance of InGaAlP low-power surface-mount device (SMD) LED.

Thermal parameters of the LED were measured using thermal transient measurement via Thermal Transient Tester (T3Ster). The experimental results were validated using computational fluid dynamics (CFD) software.

As input current increases from 50 to 90 mA at 25°C, the relative increase in LED package (ΔR_thJS) and total thermal resistance (ΔR_thJA) is about 10 and 4 per cent, respectively. In addition, at 50 mA and ambient temperature from 25 to 65°C, the ΔR_thJS and ΔR_thJA are roughly 28 and 22 per cent, respectively. A good agreement between simulation and experiment results of junction temperature.

Most of previous studies have focused on thermal management of high-power LEDs. There were no studies on thermal analysis of low-power SMD LED so far. This work will help in predicting the thermal performance of low-power LEDs in solid-state lighting applications.

The purpose of this paper is to present a new method of measuring thermal resistance of power light-emitting diodes (LEDs). Properties of power LEDs strongly depend on their internal temperature. The value of this temperature depends on the cooling conditions characterized by thermal resistance.

The new method of measuring the value of this parameter belongs to the group of electric methods. In this method, the problem of estimating the value of electrical power converted into light is solved. By comparing the values of the case temperature obtained for the LED operating in the forward mode and the reverse-breakdown mode, the thermal power is estimated. On the basis of the measured value of the thermally sensitive parameter (the LED forward voltage) and the estimated value of the thermal power, thermal resistance is calculated.

The elaborated method was used to measure thermal resistance of the selected types of power LEDs operating at different cooling conditions. The correctness of the elaborated measurement method was proved by comparing the results of measurements obtained with the use of the new method and the infrared method.

On the basis of the obtained results of measurements and the catalog data of the tested diodes, the dependence of the measurement error of thermal resistance of the LED on its luminous efficiency is discussed.

The new measurement method is easy to use and more accurate than the classical method of thermal resistance measurement of the diode.

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 inappropriate lighting methods can have irreversible effects on artworks available in museums and exhibitions. Several factors affect the choice of the lighting system in the museums. By surveying all possible elements, this paper aims to propose a sustainability-based solution, as it relates to the development of artwork conservation, visual perception and energy efficiency during operation and maintenance (O&M).

The paper elicits optimal solutions out of the method presented based on functions and expert opinion to improve lighting quality in existing museums. To study the optimization, the energy consumption and life cycle cost (LCC) in both the proposed lighting and the existing lighting system are compared using HoneyBee and LadyBug plugins in GrassHopper, as well as BLCC5 energy cost estimation software.

The results indicated a practical method to select the most suitable solution for museum lighting. By applying the proposed solutions obtained from the case study, a significant reduction in energy consumption and LCC were achieved. Besides, greenhouse gases were remarkably decreased.

Providing the proper lighting systems for each museum is the issue that is given special attention during the facilities management. The quality of the lighting, energy consumption and costs are analyzed by the simulation software. It is recommended that the validity considerations of the practice are examined.

The present study tried to present an optimal method to choose the best lighting system by the simultaneous utilization of theoretical and practical aspects. The functional model is also introduced for performing the most effective method to enhance the lighting techniques in the art museums.

The purpose of this paper is to present an electrothermal model of the module containing power light emitting diodes (LEDs) situated on a common base.

The electrothermal model of this device, which takes into account both self-heating and mutual thermal coupling between the diodes situated in this module, is described.

The correctness of the presented model is verified experimentally, and a good agreement of the calculated and measured optical and thermal characteristics of the considered module is obtained.

The presented model can be used for different structures of the LED module, but electrical inertia in the diodes is omitted.

The presented model was used to calculate electrical, thermal and optical waveforms of the module OSPR3XW1 containing three power LED situated on the common base.

The presented model takes into account thermal inertia in the considered LED module and its cooling systems with mutual thermal coupling between all the diodes situated in the same module.