Least-squares fit of a linear combination of functions

We propose that given a data-set $S=\{(x_i,y_i)/i=1,2,{\dots}n\}$ and real-valued functions $\{f_\alpha(x)/\alpha=1,2,{\dots}m\},$ the least-squares fit vector $A=\{a_\alpha\}$ for $y=\sum_\alpha a_{\alpha}f_\alpha(x)$ is $A = (F^TF)^{-1}F^TY$ where $[F_{i\alpha}]=[f_\alpha(x_i)].$ We test this formalism by deriving the algebraic expressions of the regression coefficients in $y = ax + b$ and in $y = ax^2 + bx + c.$ As a practical application, we successfully arrive at the coefficients in the semi-empirical mass formula of nuclear physics. The formalism is {\it generic} - it has the potential of being applicable to any {\it type} of $\{x_i\}$ as long as there exist appropriate $\{f_\alpha\}.$ The method can be exploited with a CAS or an object-oriented language and is excellently suitable for parallel-processing

Integrating sustainable supply chain practices with operational performance: An exploratory study of Chinese SMEs

With growing regulatory and market pressure to implement green practices, SMEs are facing enormous challenges to simultaneously improve operational and green performances of their supply chains. The paper aims to understand the green practices adopted by Chinese SMEs in the packaging sector in order to assess the impact of these practices in improving the operational performance. Case study-based research methodology is adopted and semi-structured interviews are conducted to collect data from seven SMEs in this study. Both in-case and cross-case analyses are performed to understand the green practices being adopted with the focus on improving the operational performance. The findings of this study indicate that although most SMEs understand the importance of green practices, they have limited knowledge to integrate these practices to improve operational performance. Integration and alignment of green activities with the operational improvement measures are identified as critical factors to develop an efficient green supply chain

Baryogenesis from Primordial Blackholes after Electroweak Phase Transition

Incorporating a realistic model for accretion of ultra-relativistic particles by primordial blackholes (PBHs), we study the evolution of an Einstein-de Sitter universe consisting of PBHs embedded in a thermal bath from the epoch $\sim 10^{-33}$ sec to $\sim 5\times 10^{-9}$ sec. In this paper we use Barrow et al's ansatz to model blackhole evaporation in which the modified Hawking temperature goes to zero in the limit of the blackhole attaining a relic state with mass $\sim m_{pl}$. Both single mass PBH case as well as the case in which blackhole masses are distributed in the range $8\times 10^2 - 3\times 10^5$ gm have been considered in our analysis. Blackholes with mass larger than $\sim 10^5$ gm appear to survive beyond the electroweak phase transition and, therefore, successfully manage to create baryon excess via $X-\bar X$ emissions, averting the baryon number wash-out due to sphalerons. In this scenario, we find that the contribution to the baryon-to-entropy ratio by PBHs of initial mass $m$ is given by $\sim \epsilon \zeta (m/1 {gm})^{-1}$, where $\epsilon$ and $\zeta$ are the CP-violating parameter and the initial mass fraction of the PBHs, respectively. For $\epsilon$ larger than $\sim 10^{-4}$, the observed matter-antimatter asymmetry in the universe can be attributed to the evaporation of PBHs.Comment: Latex2e file with seven figures included as postscript file

Investigating innovation capability and organizational performance in service firms

In the service firm, innovation capability influences both financial and nonfinancial performance. It is crucial for businesses to address key challenges anticipated by the changes in socioeconomic and environmental issues. Innovation capability is largely seen as a vital source for generating sustainable competitive advantage. This article investigates the determinants of innovation capability and their relationship with organizational performance in the Jordanian banking sector

Modifier Based Enhancement in Physical and Chemical Properties of Bitumen

Bitumen is used worldwide in the construction of flexible pavements and because of its wide applicability its performance is needed to be improved in all regards like, Chemical, and thermal stability, fatigue life, moisture susceptibility, mechanical strength, temperature susceptibility, rutting resistance, ageing resistance, tensile strength, viscosity, stiffness etc. In this connection, researchers have used various modifiers to improve the pavement performance. The present paper provides a brief review of different modifiers in road making industry. Some popular polymer modifiers like low density polythene, high density polythene, polypropylene, ethyl vinyl acetate, styrene butadiene styrene and industrial waste are reviewed in terms of their role in bitumen modification. It also discusses enhancement in properties of bitumen after modification in order to improve properties of pavement. Through the reviewed literature, it is found that the addition of the polymers to bitumen tends to enhance fatigue and cracking resistance mainly. The future development and recommendation in modifiers for bitumen modification are also suggested in the end.</jats:p