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PSP full helicopter Out ground effect
No full textThis data contains results file of the PSP rotor with fuselage for out of ground effec
Commodity reference price transparency: conceptualization, measurement instrument development, and influence on commodity price management.
Get PDFCommodity reference price (CRP) is potentially an important commodity price
management influencing factor. However, despite its importance, it remains
under-researched and poorly understood. Anchored in contingency theory and
building on previous studies, this study (a) conceptualizes CRP contingency as
CRP transparency, (b) creates a CRP transparency index as a tool for classifying
and evaluating CRP, and (c) demonstrates the CRP transparency impact on CRP
functions and CPM practices.
Intuitive and interpretive literature reviews are combined with nine directed expert
interviews to uncover the CRP transparency attributes. Subsequently, 111
interviews with purchasing managers explore a purposive sample of 22 CRP to
construct and populate the CRP transparency index and to explore its theoretical
and practical relevance, in particular, how individual CRP transparency levels
shape CRP functions and impact the availability, choice and performance of
commodity price management practices.
The main contributions of this thesis to theory are (a) conceptualizing CRP
transparency as a multi-dimensional construct composed of four measured
attributes: accuracy, completeness, publication frequency, and methodology, (b)
operationalizing these measured attributes into five transparency levels, (c)
constructing CRP transparency index divided into five distinct and meaningful
levels following a geological metaphor: black hole, opaque, translucent,
transparent, dazzle. From a practitioner standpoint, this thesis provides
actionable insights into (i) CRP transparency assessment and comparison with
alternative CRP, (ii) how CRP transparency shapes the commodity price
management practices and CRP functions and, (iii) offers an empirical toolbox
for assessing, comparing, and configuring CRP to regulators and CRP issuers.PhD in Leadership and Managemen
Understanding the joint impacts of soil architecture and microbial dynamics on soil functions: insights derived from microscale models
Get PDFOver the last decades, a new generation of microscale models has been developed to simulate soil microbial activity. An earlier article (Pot et al., 2021) presented a detailed review of the description of soil architecture and microbial dynamics in these models. In the present article, we summarise the main results obtained by these models according to six model outputs: growth and spatial organisation of microbial colonies, soil hydraulic conductivity, coexistence and trophic interactions of microorganisms, temporal dynamics of the amount of solid and dissolved organic matter in soil and, microbial production of CO2. For each of these outputs, we draw particular attention to the respective roles of soil architecture and microbial dynamics, and we report how microscale models allow for disentangling and quantifying them. We finally discuss limitations and future directions of microscale models in combination with the on-going development of high-performance imaging tools revealing the spatial heterogeneity of the actors of soil microbial activity.Natural Environment Research Council (NERC): NE/P014208/1; NE/S004920/1.European Journal of Soil Scienc
Efficacy of bioadmendments in reducing the influence of salinity on the bioremediation of oil-contaminated soil
Get PDFThis study aimed to investigate the potential of three bioamendments (rice husk biochar, wheat straw biochar, and spent mushroom compost) to enhance microbial degradation of crude oil in saline soil. A soil microcosm experiment was conducted, comparing the response of soil microorganisms to crude oil under saline (1 % NaCl) and non-saline conditions. The soils were amended with different bioamendments at varying concentrations (2.5 % or 5 %), and degradation rates were monitored over a 120-day period at 20 °C. The results showed that the bioamendments significantly influenced the degradation of total petroleum hydrocarbons (TPH) in both non-saline and saline soils by 67 % and 18 % respectively. Non-saline soils exhibited approximately four times higher TPH biodegradation compared to saline soils. Among the bioamendments, rice husk biochar and spent mushroom compost had the greatest impact on biodegradation in saline soil, while wheat straw and rice husk biochar combined with spent mushroom compost showed the most significant effects in non-saline soil. The study also revealed that the bioamendments facilitated changes in the microbial community structure, particularly in the treatments with rice husk biochar and wheat straw biochar. Actinomycetes and fungi were found to be more tolerant to soil salinity, especially in the treatments with rice husk biochar and wheat straw biochar. Additionally, the production of CO2, indicating microbial activity, was highest (56 % and 60 %) in the treatments combining rice husk biochar or wheat straw biochar with spent mushroom compost in non-saline soil, while in saline soil rice husk biochar treatment (50 %) was the highest. Overall, this research demonstrates that the application of bioamendments, particularly rice husk biochar and wheat straw biochar combined with spent mushroom compost, can effectively enhance the biodegradation of crude oil in saline soil. These findings highlight the potential of such bioamendments as green and sustainable solutions for soil pollution, especially in the context of climate change-induced impacts on high-salinity soils, including coastal soils
Propulsion integration study of civil aero-engine nacelles
Get PDFIt is envisaged that future civil aero-engines will operate with ultra-high bypass ratios to reduce the specific fuel consumption. To achieve the expected benefits from the new engine cycles, these new powerplants may mount compact nacelles. For these new configurations the aerodynamic coupling between the powerplant and the airframe may increase. For this reason, it is required to quantify and further understand the effects of aircraft integration for compact aero-engine nacelles. This study provides an insight of the changes in flow aerodynamics as well as quantification of the most relevant performance metrics of the powerplant, airframe and the combined aircraft system across a range of different installation positions. Relative to a conventional architecture, there is an aerodynamic benefit in net vehicle force of about 1.2% for a compact powerplant when installed in forward positions. This is the same improvement that was identified when the aero-engine nacelles were in isolation. However, for close-coupled installation positions, the aerodynamic benefit in net vehicle force erodes to 0.44% due to the larger effects of aircraft integration on compact nacelles.The Aeronautical Journa
Birth of dairy 4.0: opportunities and challenges in adoption of fourth industrial revolution technologies in the production of milk and its derivative
Get PDFEmbracing innovation and emerging technologies is becoming increasingly important to address the current global challenges facing many food industry sectors, including the dairy industry. Growing literature shows that the adoption of technologies of the fourth industrial revolution (named Industry 4.0) has promising potential to bring about breakthroughs and new insights and unlock advancement opportunities in many areas of the food manufacturing sector. This article discusses the current knowledge and recent trends and progress on the application of Industry 4.0 innovations in the dairy industry. First, the “Dairy 4.0” concept, inspired by Industry 4.0, is introduced and its enabling technologies are determined. Second, relevant examples of the use of Dairy 4.0 technologies in milk and its derived products are presented. Finally, conclusions and future perspectives are given. The results revealed that robotics, 3D printing, Artificial Intelligence, the Internet of Things, Big Data, and blockchain are the main enabling technologies of Dairy 4.0. These advanced technologies are being progressively adopted in the dairy sector, from farm to table, making significant and profound changes in the production of milk, cheese, and other dairy products. It is expected that, in the near future, new digital innovations will emerge, and greater implementations of Dairy 4.0 technologies is likely to be achieved, leading to more automation and optimization of this dynamic food sector.Current Research in Food Scienc
Effect of inter layer cold work on 2024 aluminium alloy produced by wire directed energy deposition
Get PDFAluminium copper magnesium alloys are widely used in the aerospace sector. Wire-based Directed Energy Deposition could replace conventional manufacturing routes to build large and semi-complex components for this industry if high mechanical performance can be achieved in the deposit.
The scope of this study was to assess the effect of inter-pass rolling on a 2024 aluminium alloy wire-based DED built structure and to investigate the impact of cold work during the deposition process on the microstructure and mechanical performances. The 2024 aluminium alloy was deposited using two variants of gas metal arc process, and the effects of the deposition process, cold work and heat treatment were studied using macro and microstructural observations, hardness measurement and tensile tests. The material response to inter-pass rolling and the formation of rolling defects was found to depend on the deposition process variant and bead geometry. While a significant strengthening of the deposit was observed with one process, only a drastic reduction of defects was observed with the second. It was also found that the application of cold work and heat treatment led to lowering of anisotropy and higher ductility when compared with heat-treated deposit without any inter-pass rolling.Materials Science and Engineering:
Stability and hazard properties of improvised nitrocellulose
Get PDFNitrocellulose is a vulnerable and sensitive energetic material that can easily be manufactured from ordinary household chemicals and used for illicit purposes. Hazards of this material can lead to incidents resulting from unplanned initiation in manufacturing, storage or handling. Thermal stability and hazard data for so-called improvised nitrocellulose (IN) are crucial to formulate guidance for storage and handling of such materials recovered from illegal possession. This study focused on the energy content, stability and safety properties of IN. The energy contents increase linearly with nitrogen contents of IN. Improvised nitrocellulose showed a similar sensitivity to impact and electrostatic discharge, but vacuum stability testing demonstrated more gas release (2.8–3.4 cm3 g−1) compared to commercial NC (1.7 cm3 g−1). Chemiluminescence analysis established activation energies for hydrolytic and thermolytic decomposition to be 36 and ~93 kJ mol-1, respectively. Results suggest that NC samples recovered from improvised devices or illegal possession should be handled with special care.Journal of Energetic Material
Fact-based nutrition for infants and lactating mothers – The NUTRISHIELD study
Get PDFBackground: Human milk (HM) is the ideal source of nutrients for infants. Its composition is highly variable according to the infant’s needs. When not enough own mother’s milk (OMM) is available, the administration of pasteurized donor human milk (DHM) is considered a suitable alternative for preterm infants. This study protocol describes the NUTRISHIELD clinical study. The aim of this study is to evaluate the influence of diet, lifestyle habits, psychological stress, and pasteurization on the milk composition, and how it modulates infant’s growth, health, and development.
Methods and design: NUTRISHIELD is a prospective mother-infant birth cohort in the Spanish-Mediterranean area including three groups: preterm infants <32 weeks of gestation (i) exclusively receiving OMM, and (ii) exclusively receiving DHM, and (iii) term infants exclusively receiving OMM, as well as their mothers. Biological samples and nutritional, clinical, and anthropometric characteristics are collected at six time points covering the period from birth and until six months of infant’s age. The genotype, metabolome, and microbiota as well as the HM composition (i.e., macronutrients, fatty acids, vitamins, human milk oligosaccharides, and steroids) are characterized. Portable sensor prototypes for the analysis of HM and urine are benchmarked. Additionally, maternal psychosocial status is measured at the beginning of the study and at month six, including social support, family functioning, perceived stress, anxiety, and depression symptoms, and traumatic life events. Mother-infant postpartum bonding and parental stress are also examined. At six months, infant neurodevelopment scales are applied. Mother’s concerns and attitudes to breastfeeding are also registered through a specific questionnaire.
Discussion: NUTRISHIELD provides an in-depth longitudinal study of the mother-infant-microbiota triad combining multiple biological matrices, newly developed analytical methods, and ad-hoc designed sensor prototypes with a wide range of clinical outcome measures. Data obtained from this study will be used to train a machine-learning algorithm for providing dietary advice to lactating mothers and will be implemented in a user-friendly platform based on a combination of user-provided information and biomarker analysis. A better understanding of the factors affecting milk’s composition, together with the health implications for infants plays an important role in developing improved strategies of nutraceutical management in infant care.Frontiers in Pediatric
A review on the pollution assessment of hazardous materials and the resultant biorefinery products in Palm oil mill effluent
Get PDFThe voluminous nature of POME is directly associated with environmental hazards and could be turned into biorefinery products. The POME, rich in BOD, COD, and oil and grease, with few hazardous materials such as siloxanes, fatty acid methyl ester, and phenolic compounds may significantly increase the risk of violating the effluent quality standards. Recently, the application of chemical and biological risk assessment that can use electrochemical sensors and microalgae-like species has gained paramount attention towards its remediation. This review describes the existing risk assessment for POME and recommends a novel assessment approach using fish species including invasive ones as suitable for identifying the toxicants. Various physico-chemical and biological treatments such as adsorption, coagulation-flocculation, photo-oxidation, solar-assisted extraction, anaerobic digestion, integrated anaerobic-aerobic, and microalgae cultivation has been investigated. This paper offers an overview of anaerobic technologies, with particular emphasis on advanced bioreactors and their prospects for industrial-level applications. To illustrate, palmitic acid and oleic acid, the precursors of fatty acid methyl ester found in POME pave the way to produce biodiesel with 91.45%. Although there are some challenges in attaining production at an economic scale, this review offers some opportunities that could help in overcoming these challenges.Environmental Pollutio