Development of Conceptual Motivation Framework to Enhance Construction Labour Productivity in the UK

Motivation is essential because labour performance depends on motivation. The study presents vital motivation factors influencing labour productivity and the relationship between social compliance, motivation, and productivity for decision-making. The construction industry in the U.K. is to become the largest construction market by 2030. However, construction productivity in the U.K. is low relative to other industries, resulting in a skilled labour shortage and low productivity growth. Hence, the opportunities for research to improve productivity in constructing for the future through motivation by social compliance. The study conducts a critical literature review of 32 significant motivation and productivity articles from construction and other industries in an online database to identify 31 factors. The findings indicate that motivation mediates social compliance and productivity. The study developed a conceptual motivation framework that indicates a positive relationship with motivation, social compliance, and productivity. The next stage is empirically testing the framework on sites

Leptogenesis from Soft Supersymmetry Breaking (Soft Leptogenesis)

Soft leptogenesis is a scenario in which the cosmic baryon asymmetry is produced from a lepton asymmetry generated in the decays of heavy sneutrinos (the partners of the singlet neutrinos of the seesaw) and where the relevant sources of CP violation are the complex phases of soft supersymmetry-breaking terms. We explain the motivations for soft leptogenesis, and review its basic ingredients: the different CP-violating contributions, the crucial role played by thermal corrections, and the enhancement of the efficiency from lepton flavour effects. We also discuss the high temperature regime $T > 10^7$ GeV in which the cosmic baryon asymmetry originates from an initial asymmetry of an anomalous $R$-charge, and soft leptogenesis reembodies in $R$-genesis.Comment: References updated. Some minor corrections to match the published versio

High energy spin excitations in YBa_2 Cu_3 O_{6.5}

Inelastic neutron scattering has been used to obtain a comprehensive description of the absolute dynamical spin susceptibility $\chi'' (q,\omega)$ of the underdoped superconducting cuprate YBa_2 Cu_3 O_{6.5} ($T_c = 52 K$) over a wide range of energies and temperatures ($2 meV \leq \hbar \omega \leq 120 meV$ and $5K \leq T \leq 200K$). Spin excitations of two different symmetries (even and odd under exchange of two adjacent CuO_2 layers) are observed which, surprisingly, are characterized by different temperature dependences. The excitations show dispersive behavior at high energies.Comment: 15 pages, 5 figure

Development of Conceptual Motivational Framework to Improve Construction Labour Productivity in the U.K.

The theoretical study presents vital motivational factors influencing labour productivity and understanding the relationship between motivation, social compliance, and labour productivity for decision-making. Labour motivation is essential because the quality of labour performance depends upon motivation. Labour who put forth more effort makes a big difference in company productivity. The construction industry in the U.K. is to become Europe’s largest construction market by 2030. However, the trend of construction industry productivity in the U.K. has been low relative to other industries resulting in a skilled labour shortage, project delays, high construction costs, and low productivity growth as foreign migrants execute most projects. The U.K. serves as a security for the concerns of Middle Eastern and other war-torn countries, including the effects of the Ukraine war. It is the largest market for U.S.A. service exports, thus accepting more migrants. Therefore, demands for housing projects are ever-increasing, leading to a rise in construction projects that present opportunities for research to improve productivity through motivation by enhancing social compliance. The findings indicate that motivation mediates social compliance and labour productivity and that the essential way to motivate labour is by upholding social compliance. The present study conducts a comprehensive literature review to identify motivational factors influencing labour productivity. The findings developed a conceptual motivational framework that indicates a positive relationship between motivation, social compliance, and labour productivity. The next level is to test the framework on construction sites empirically through pragmatism philosophy with quantitative and qualitative approaches

Quantum Impurities and the Neutron Resonance Peak in YBa2Cu3O7{\bf YBa_2 Cu_3 O_7}: Ni versus Zn

The influence of magnetic (S=1) and nonmagnetic (S=0) impurities on the spin dynamics of an optimally doped high temperature superconductor is compared in two samples with almost identical superconducting transition temperatures: YBa$_2$(Cu$_{0.97}$Ni$_{0.03}$)$_3$O$_7$ (T$_c$=80 K) and YBa$_2$(Cu$_{0.99}$Zn$_{0.01}$)$_3$O$_7$ (T$_c$=78 K). In the Ni-substituted system, the magnetic resonance peak (which is observed at E$_r \simeq$40 meV in the pure system) shifts to lower energy with a preserved E$_r$/T$_c$ ratio while the shift is much smaller upon Zn substitution. By contrast Zn, but not Ni, restores significant spin fluctuations around 40 meV in the normal state. These observations are discussed in the light of models proposed for the magnetic resonance peak.Comment: 3 figures, submitted to PR

Superconductivity-Induced Anomalies in the Spin Excitation Spectra of Underdoped YBa_2 Cu_3 O_{6+x}

Polarized and unpolarized neutron scattering has been used to determine the effect of superconductivity on the magnetic excitation spectra of YBa_2 Cu_3 O_{6.5} (T_c = 52K) and YBa_2 Cu_3 O_{6.7} (T_c = 67K). Pronounced enhancements of the spectral weight centered around 25 meV and 33 meV, respectively, are observed below T_c in both crystals, compensated predominantly by a loss of spectral weight at higher energies. The data provide important clues to the origin of the 40 meV magnetic resonance peak in YBa_2 Cu_3 O_7.Comment: LaTex, 4 pages, 4 ps figures. to appear in Phys. Rev. Let

On Measuring Condensate Fraction in Superconductors

An analysis of off-diagonal long-range order in superconductors shows that the spin-spin correlation function is significantly influenced by the order if the order parameter is anisotropic on a microscopic scale. Thus, magnetic neutron scattering can provide a direct measurement of the condensate fraction of a superconductor. It is also argued that recent measurements in high temperature superconductors come very close to achieving this goal.Comment: 4 pages, 1 eps figure, RevTex. A new possibility in the underdoped regime is added. Other corrections are mino

The scaling properties of exchange and correlation holes of the valence shell of second row atoms

We study the exchange and correlation hole of the valence shell of second row atoms using variational Monte Carlo techniques, especially correlated estimates, and norm-conserving pseudopotentials. The well-known scaling of the valence shell provides a tool to probe the behavior of exchange and correlation as a functional of the density and thus test models of density functional theory. The exchange hole shows an interesting competition between two scaling forms -- one caused by self-interaction and another that is approximately invariant under particle number, related to the known invariance of exchange under uniform scaling to high density and constant particle number. The correlation hole shows a scaling trend that is marked by the finite size of the atom relative to the radius of the hole. Both trends are well captured in the main by the Perdew-Burke-Ernzerhof generalized-gradient approximation model for the exchange-correlation hole and energy.Comment: 18 pages, 8 figure

Long-term efficacy of an education programme in improving adherence with continuous positive airway pressure treatment for obstructive sleep apnoea

This randomised controlled trial demonstrated that a motivational enhancement programme composed of a single interview and a follow-up phone call at the initiation of continuous positive airway pressure treatment can improve treatment adherence in subjects with obstructive sleep apnoea, even after 1 year, and lead to better health outcome in terms of reducing daytime sleepiness.published_or_final_versio

Finite-Size Studies on the SO(5) Symmetry of the Hubbard Model

We present numerical evidence for the approximate SO(5) symmetry of the Hubbard model on a 10 site cluster. Various dynamic correlation functions involving the $\pi$ operators, the generators of the SO(5) algebra, are studied using exact diagonalisation, and are found to possess sharp collective peaks. Our numerical results also lend support on the interpretation of the recent resonant neutron scattering peaks in the YBCO superconductors in terms of the Goldstone modes of the spontaneously broken SO(5) symmetry.Comment: 4 pages, Rev-Tex, includes 2 eps figure