2,737 research outputs found
Materials Procurement Conceptual Framework for Minimising Waste in the Egyptian Construction Industry
The construction industry plays a crucial role in achieving the social and economic development of countries worldwide. However, construction projects are associated with materials waste, referred to as construction and demolition waste (CDW), generated at different stages of the construction process. In Egypt's particular case, the CDW problem has become a significant challenge, and the need to find sustainable solutions is overwhelming. Unfortunately, the Egyptian construction sector lacks a conceptual framework of materials procurement practices compounded by surrounding external factors of legislation, awareness measures, and culture & behaviour measures for CDW reduction (CDWR). Towards addressing the CDW problem, this study introduces a theoretical framework which was tested through a survey questionnaire distributed among a representative sample of Egyptian construction firms' total population. Through the survey questionnaire, this study was able to: (1) determine the current applicability and effectiveness levels of different CDWR factors’ components in the Egyptian construction sector; (2) examine the effect of different practices, legislation, culture & behaviour measures, and awareness measures on CDWR; and (3) develop and introduce a conceptual framework consisting of the CDWR factors along with their components. The overall contributions of this study include (1) presenting CDWR factors along with their components needed for overcoming the CDW problem in Egypt via a conceptual framework; (2) demonstrating the importance of waste-efficient materials procurement practices, a rarely explored research area, in tackling CDW problem; (3)
highlighting shortcomings in Egyptian CDWM legislation and the GPRS and proposing recommendations for their improvement; (4) encouraging more research on CDWM through waste-efficient materials procurement practices; and (5) promoting the application of the structural equation modelling (SEM) technique in the construction research domain in developing and introducing conceptual frameworks. Generally, a materials procurement conceptual framework to reduce CDW in the Egyptian construction sector is developed with recommendations and policy guidance for overcoming CDW problem in Egypt. While acknowledging issues of CDW can be country specific, it is expected that given the structural
similarity of African construction industry, findings from this study can be of benefits to other African countries other than Egypt contending CDWR issues
Quality of Governance, Corruption and Absolute Child Poverty in India
Mundle, Chakraborty, Chowdhury and Sikdar (2012) developed the first quality of governance (QoG) measures to assess the performance of India’s states. The present article builds on Mundle et al.’s (2012) framework by analyzing the relationship between their QoG measures and absolute child poverty in India. The empirical analysis also includes corruption indicators from Transparency International to test the relative importance of corruption and governance for combating child poverty. I combine macro (states) and micro data (children) with multilevel statistical models to achieve this task. A key finding is that governance has more explanatory power than corruption. Further, among Mundleetal.’s six measures, the BORDA measure performs consistently better and explains about 60 per cent of the between-states variation: one unit improvement in BORDA yields about 1 per cent decrease in absolute child poverty. The sensitivity of this inference is tested with regards to severe education, shelter and food deprivation
Synthesizing the Malthusian and Senian Approaches on Scarcity: A Realist Account
Food entitlement decline (FED) and food availability decline (FAD) are two approaches to explaining famines that have different policy implications. One focuses on the systemic level, whereas the other is concerned with the individual level. They therefore analyse relatively distinct causal mechanisms. Thus, an important question is whether these approaches can be reconciled. Another related question is how FAD- and FED-based explanations relate to classical Malthusian views about rapid food requirement increase (FRI). This paper analyses these questions and argues that these three approaches can indeed be reconciled within a single framework by outlining the causal sources of FAD, FED and FRI. This task requires, among other things, the separation of ontological categories and empirical measures. As a consequence of this argument, the paper suggests that there are only seven possible ontological combinations of how a famine situation can arise as a direct cause. Simultaneously, it maintains that there are virtually an infinite number of ways in which these combinations may act as indirect causes (rooted in economic, political and social conditions). The analysis is exemplified by the Bengal famine of 1943 because that famine is a well-known case. The wider research and policy applicability of this general account are discussed but have yet to be tested in relation to other scarcity cases (water, land, fish). This synthesis is made possible by the incorporation of critical realist interventions into economic theory.1. Introduction 2. Linking FAD, FED and FRI through a general framework for scarcity events 3. The 1943 Bengal famine: an example 4. A synchronic analysis of FAD, FED and FRI in the Bengal case 5. Discussion - further research and policy recommendations Frequently used acronyms Bibliograph
Thermodynamics of micellization of oppositely charged polymers
The complexation of oppositely charged colloidal objects is considered in
this paper as a thermodynamic micellization process where each kind of object
needs the others to micellize. This requirement gives rise to quantitatively
different behaviors than the so-called mixed-micellization where each specie
can micellize separately. A simple model of the grand potential for micelles is
proposed to corroborate the predictions of this general approach.Comment: 7 pages, 2 figures. Accepted for publication in Europhysics Letter
Phase operators, temporally stable phase states, mutually unbiased bases and exactly solvable quantum systems
We introduce a one-parameter generalized oscillator algebra A(k) (that covers
the case of the harmonic oscillator algebra) and discuss its finite- and
infinite-dimensional representations according to the sign of the parameter k.
We define an (Hamiltonian) operator associated with A(k) and examine the
degeneracies of its spectrum. For the finite (when k < 0) and the infinite
(when k > 0 or = 0) representations of A(k), we construct the associated phase
operators and build temporally stable phase states as eigenstates of the phase
operators. To overcome the difficulties related to the phase operator in the
infinite-dimensional case and to avoid the degeneracy problem for the
finite-dimensional case, we introduce a truncation procedure which generalizes
the one used by Pegg and Barnett for the harmonic oscillator. This yields a
truncated generalized oscillator algebra A(k,s), where s denotes the truncation
order. We construct two types of temporally stable states for A(k,s) (as
eigenstates of a phase operator and as eigenstates of a polynomial in the
generators of A(k,s)). Two applications are considered in this article. The
first concerns physical realizations of A(k) and A(k,s) in the context of
one-dimensional quantum systems with finite (Morse system) or infinite
(Poeschl-Teller system) discrete spectra. The second deals with mutually
unbiased bases used in quantum information.Comment: Accepted for publication in Journal of Physics A: Mathematical and
Theoretical as a pape
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