Photoluminescence from In0.5Ga0.5As/GaP quantum dots coupled to photonic crystal cavities

We demonstrate room temperature visible wavelength photoluminescence from In0.5Ga0.5As quantum dots embedded in a GaP membrane. Time-resolved above band photoluminescence measurements of quantum dot emission show a biexpontential decay with lifetimes of ~200 ps. We fabricate photonic crystal cavities which provide enhanced outcoupling of quantum dot emission, allowing the observation of narrow lines indicative of single quantum dot emission. This materials system is compatible with monolithic integration on Si, and is promising for high efficiency detection of single quantum dot emission as well as optoelectronic devices emitting at visible wavelengths

Psycho-Demographic Determinants of Young Consumers’ Intention towards Purchasing Counterfeit Apparel in a U.S. Counterfeit Capital

The purpose of this study was to examine key psycho-demographic determinants that influenced consumers’ attitude and purchase intention of counterfeit apparel. Using a survey method, a convenience and purposeful sample of 118 young consumers in Los Angeles County was used for this study. From the series of multiple regressions, we found that none of the six personality traits (integrity, materialism, novelty seeking, personal gratification, status consumption, and value consciousness) played a significant role of conforming the participants’ attitudes towards counterfeit apparel. However, the two personality traits (value consciousness and integrity) along with the two demographic variables (gender and income) played a significant role for their intention of purchasing counterfeit apparel, which are the interesting findings of this study. Limitations and implications were also presented for future studies

Holistic Integration of Product Attributes with Consumer Behavioral Aspects for the Use of Wearable Technology

The use of wearable technology is rapidly increasing to meet diverse consumer needs and desires. To design, develop, and produce a successful product embedding wearable technology, it is crucial to know consumers’ preferences, expectations, and needs, which enables industry professionals to predict consumers’ attitudes towards the wearables and their purchase intentions. The purpose of this study is to propose a holistic framework, embedding various concepts (e.g., intrinsic and extrinsic attributes) that should be considered when conducting study on consumers’ purchase intention towards the use of wearables. Various models related to the consumer behavior and product design and development have been examined and used to develop this proposed framework, which can assist product designers, developers, manufacturers, and merchandisers to identify the essential product attributes, consumers’ needs and expectations of wearables and let them have a more precise and successful product design and development based on the target consumers’ needs

Range reduction using fixed points

National audienceThe efficiency of sBB depends on many parameters, among which the width of the variable ranges at each node. The fastest range reduction algorithm is called Feasibility-Based Bounds Tightening (FBBT) : it is an iterative procedure that propagates bounds up and down the expression trees [1] representing the constraints in (1), tightening them by using the constraint bounds (-?, 0]. Depending on the instance, and even limited to linear constraints only, FBBT may not converge finitely to its limit point. Tolerance-based termination criteria yield finite termination but, in general, in unbounded time (for every time bound, there is an instance exceeding it). So, although the FBBT is practically fast, its theoretical worst-case complexity status is far from satisfactory

On feasibility based bounds tightening

http://www.optimization-online.org/DB_HTML/2012/01/3325.htmlMathematical programming problems involving nonconvexities are usually solved to optimality using a (spatial) Branch-and-Bound algorithm. Algorithmic e?ciency depends on many factors, among which the widths of the bounding box for the problem variables at each Branch-and-Bound node naturally plays a critical role. The practically fastest box-tightening algorithm is known as FBBT (Feasibility-Based Bounds Tightening): an iterative procedure to tighten the variable ranges. Depending on the instance, FBBT may not converge ?nitely to its limit ranges, even in the case of linear constraints. Tolerance-based termination criteria yield ?nite termination, but not in worstcase polynomial-time. We model FBBT by using ?xed-point equations in terms of the variable bounding box, and we treat these equations as constraints of an auxiliary mathematical program. We demonstrate that the auxiliary mathematical problem is a linear program, which can of course be solved in polynomial time. We demonstrate the usefulness of our approach by improving an existing Branch-and-Bound implementation. global optimization, MINLP, spatial Branch-and-Bound, range reduction