980 resultados para tender preparation process
Resumo:
Cost estimation process is undertaken to predict the total cost of the project. Studies indicate that one of the construction company failures in contracting is because of the uncertain, incorrect, and unrealistic cost estimation. Cost estimation process are heavily influenced by the complexity of the project, scale and scope of construction, market conditions, method of construction, site constraints, client’s financial position, buildability and the location of the project. However, there are other combinations factors that have not been studied thus far. Hence, this paper focuses on the review of other researchers’ findings in relation to cost estimation issues in the construction industry. Among the findings, it has been revealed that the cost estimation issues are related to accuracy, human factors, practical knowledge and insufficient cost data/information. The aim of this paper is to investigate these factors and determining other potential factors that may influence cost estimation process in the construction industry.
Resumo:
The possibility of winning the tender is subject to the cost estimation proposed by the contractors compared to the cost estimation prepared by the client’s representative. Studies indicated that one of the construction company failures in the tendering process is due to the uncertain, incorrect, and unrealistic cost estimation. Failure to provide a competitive cost estimation on time is the main reason the contractor is not successful in winning the tender, and will not be considered for the tender evaluation stage. The aim of this paper is to validate the key factors that affect the cost estimation activities in the tender preparation process. This paper describes the results of a pilot study, from a questionnaire survey on the factors that affect the cost estimation activities in the tender preparation process. The study shows the importance of all the factors in the cost estimation activities in the tender preparation process in terms of human factors, working culture, and information technology.
Resumo:
(EN)Disclosed are a WC/CNT, WC/CNT/Pt composite material and a preparation process therefor and use thereof. The WC/CNT/Pt composite material comprises mesoporous spherical tungsten carbide with a diameter of 1-5 microns, carbon nanotubes and platinum nano particles, with the carbon nanotubes growing on the surface of the mesoporous spherical tungsten carbide and expanding outward, and the platinum nano particles growing on the surfaces of the mesoporous spherical tungsten carbide and carbon nanotubes. The WC/CNT composite material comprises mesoporous spherical tungsten carbide with a diameter of 1-5 microns, and carbon nanotubes, with the carbon nanotubes growing on the surface of the mesoporous spherical tungsten carbide and expanding outward. The WC/CNT/Pt composite material of the present invention can be used as an electro-catalyst in a methanol flue battery, significantly improving the catalytic conversion rate and the service life of the catalyst. The WC/CNT composite material can be used as an electro-catalyst in the electro-reduction of a nitro aromatic compound, significantly improving the efficiency of organic electro-synthesis.
Resumo:
Disclosed are a WC/CNT, WC/CNT/Pt composite material and a preparation process therefor and use thereof. The WC/CNT/Pt composite material comprises mesoporous spherical tungsten carbide with a diameter of 1-5 microns, carbon nanotubes and platinum nano particles, with the carbon nanotubes growing on the surface of the mesoporous spherical tungsten carbide and expanding outward, and the platinum nano particles growing on the surfaces of the mesoporous spherical tungsten carbide and carbon nanotubes. The WC/CNT composite material comprises mesoporous spherical tungsten carbide with a diameter of 1-5 microns, and carbon nanotubes, with the carbon nanotubes growing on the surface of the mesoporous spherical tungsten carbide and expanding outward. The WC/CNT/Pt composite material of the present invention can be used as an electro-catalyst in a methanol flue battery, significantly improving the catalytic conversion rate and the service life of the catalyst. The WC/CNT composite material can be used as an electro-catalyst in the electro-reduction of a nitro aromatic compound, significantly improving the efficiency of organic electro-synthesis.
Resumo:
Disclosed are compounds of formulae (II) and (III), wherein R1 is other than hydrogen and the remaining substituents are as defined in the specification, processes for their preparation and pharmaceutical compositions containing them. The compounds are capable of inhibiting acetylcholinesterase, and are useful in the treatment of pathologies associated with cholinergic transmission, such as memory related disorders, neurodegenerative disorders such as Alzheimer's Disease, Myasthenia Gravis and intoxication induced by chemical agents.
Resumo:
In this study a novel method MicroJet reactor technology was developed to enable the custom preparation of nanoparticles. rnDanazol/HPMCP HP50 and Gliclazide/Eudragit S100 nanoparticles were used as model systems for the investigation of effects of process parameters and microjet reactor setup on the nanoparticle properties during the microjet reactor construction. rnFollowing the feasibility study of the microjet reactor system, three different nanoparticle formulations were prepared using fenofibrate as model drug. Fenofibrate nanoparticles stabilized with poloxamer 407 (FN), fenofibrate nanoparticles in hydroxypropyl methyl cellulose phthalate (HPMCP) matrix (FHN) and fenofibrate nanoparticles in HPMCP and chitosan matrix (FHCN) were prepared under controlled precipitation using MicroJet reactor technology. Particle sizes of all the nanoparticle formulations were adjusted to 200-250 nm. rnThe changes in the experimental parameters altered the system thermodynamics resulting in the production of nanoparticles between 20-1000 nm (PDI<0.2) with high drug loading efficiencies (96.5% in 20:1 polymer:drug ratio).rnDrug releases from all nanoparticle formulations were fast and complete after 15 minutes both in FaSSIF and FeSSIF medium whereas in mucodhesiveness tests, only FHCN formulation was found to be mucoadhesive. Results of the Caco-2 studies revealed that % dose absorbed values were significantly higher (p<0.01) for FHCN in both cases where FaSSIF and FeSSIF were used as transport buffer.rn
Resumo:
Building construction is a highly competitive and risky business. This competitiveness is compounded where conflicting objectives amongst contracting and subcontracting firms set the stage for an adversarial and potentially destructive business relationship. Clients, especially those from the public sector, need broader tender evaluation criteria to complement the traditional focus on bid price. There is also a need for change in the construction industry—not only to a more cooperative approach between the constructing parties—but also from a confrontationist attitude to a more harmonious relationship between all stakeholders in providing constructed facilities. A strategic alliance is a cooperative relationship between two or more organisations that forms part of their overall strategies, and contributes to achieving their major goals and objectives. Strategic alliances in building construction may provide a useful tool to assist public sector construction managers evaluate tenders and concurrently encourage more cooperative relationships amongst construction stakeholders. This paper begins with an overview of the Australian building construction industry, then reviews the existing strategic alliance literature and describes an analysis framework comprising six attributes of strategic alliances for application to construction organisations—trust, commitment, interdependence, cooperation, communication, and joint problem solving. These attributes are currently being used to collect data from 70 building construction firms in Queensland to assess their respective levels of strategic alliance. Given the trend towards broader indicators of construction firm performance, these attributes are proposed as a tool for use in the tender evaluation process for public works.
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Purpose of this paper One way in which the tendering process can be further improved is by reviewing and clarifying the high costs that participants face during the course of the tendering phase. The study aims to provide project teams working in construction tender preparation a clear picture of what to expect when tendering for infrastructure projects. Design/methodology/approach Firstly, a review of current literature on tendering in infrastructure projects is conducted to identify the associated costs affecting traditional and PPP procurements as well as the potential measures contributing to tendering cost-reduction. A theoretical framework and its corresponding research hypotheses, which are based on the literature reviewed, are then proposed. An industry-wide questionnaire survey is currently under design to solicit industry practitioners’ views on tendering costs and the associated tendering cost-reduction measures. The data collected in the survey will subject to statistical analysis to test the proposed research hypotheses, which will be reported in a forthcoming paper. Findings and value The direct and indirect costs in public-private procurement have been identified and have been categorised into internal and external costs arising from working on tender submissions. A theoretical framework, mainly composed of five mechanisms of cost reduction, has been proposed and will be tested in a forthcoming industry-wide questionnaire survey. Originality/value of paper The findings are expected to lead to a transparent tendering process in infrastructure procurement, in which there is increased engagement from the private sector as well as an increase in competitive tendering.
Resumo:
Highly active PtSn/C catalyst was prepared by a polyol method. The catalyst was reduced in H-2/Ar atmosphere at 600 degreesC for 2 h in order to obtain different metallic phase. TEM images show uniform dispersion of spherical metal nanoparticles with average diameters of 1.8 and 3.9 nm for the as-prepared and treated catalysts, respectively. UV-vis spectrophotometry is employed to monitor the preparation process and the results indicate that Pt-Sn complex formed once the precursors of Pt and Sn were mixed together. The structure properties of the samples were characterized using X-ray diffraction. The results show that after reduction, the catalyst tends to form PtSn alloy. TPR experiment results show that Sn exists in multivalent state in the as-prepared sample while only zero-valence Sn was detected in the treated sample, while it could not be excluded that the multivalent tin existed in the treated sample. Cyclic voltammetry (CV) technique and single direct ethanol fuel cell (DEFC) tests indicate that the as-prepared catalyst possesses superior catalytic activity for ethanol oxidation to the treated sample. The results suggest that Pt and multivalent Sn are the active species for ethanol oxidation. (C) 2004 Elsevier B.V. All rights reserved.
Resumo:
A simple preparation process of alkylamide phase for reversed-phase HPLC (RP-HPLC) is described. The process includes aminopropyltrimethoxysilane firstly reacted with octanoyl chloride, then the intermediate was coupled onto porous silica. The resultant bonded silica has a reproducible ligand surface concentration and homogenous bonded ligand distribution on the porous silica. Characterization of prepared packing was carried out with elemental analysis, solid-state C-13 NMR and Fourier transform infrared (FT-IR). Chromatographic evaluations were carried out by using a mixture of organic compounds including acidic, basic and neutral analytes under methanol/water as binary mobile phase. The results showed that the stationary phase have excellent chromatographic properties and can be efficiently used for the separation of basic compounds.
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BACKGROUND: Early preparation for renal replacement therapy (RRT) is recommended for patients with advanced chronic kidney disease (CKD), yet many patients initiate RRT urgently and/or are inadequately prepared. METHODS: We conducted audio-recorded, qualitative, directed telephone interviews of nephrology health care providers (n = 10, nephrologists, physician assistants, and nurses) and primary care physicians (PCPs, n = 4) to identify modifiable challenges to optimal RRT preparation to inform future interventions. We recruited providers from public safety-net hospital-based and community-based nephrology and primary care practices. We asked providers open-ended questions to assess their perceived challenges and their views on the role of PCPs and nephrologist-PCP collaboration in patients' RRT preparation. Two independent and trained abstractors coded transcribed audio-recorded interviews and identified major themes. RESULTS: Nephrology providers identified several factors contributing to patients' suboptimal RRT preparation, including health system resources (e.g., limited time for preparation, referral process delays, and poorly integrated nephrology and primary care), provider skills (e.g., their difficulty explaining CKD to patients), and patient attitudes and cultural differences (e.g., their poor understanding and acceptance of their CKD and its treatment options, their low perceived urgency for RRT preparation; their negative perceptions about RRT, lack of trust, or language differences). PCPs desired more involvement in preparation to ensure RRT transitions could be as "smooth as possible", including providing patients with emotional support, helping patients weigh RRT options, and affirming nephrologist recommendations. Both nephrology providers and PCPs desired improved collaboration, including better information exchange and delineation of roles during the RRT preparation process. CONCLUSIONS: Nephrology and primary care providers identified health system resources, provider skills, and patient attitudes and cultural differences as challenges to patients' optimal RRT preparation. Interventions to improve these factors may improve patients' preparation and initiation of optimal RRTs.
Resumo:
Researchers often experience difficulties with the negotiation of access into firms for the purpose of data collection. The question we explore is: What are the main obstacles associated with access negotiation into firms; and what strategies do researchers employ to increase their chances of success? Our research work on the tendering process of contractors took place between 2006 and 2008. We successfully negotiated access into four firms (two each in Ghana and the UK) to observe live examples of tender preparation The techniques we employed in negotiating access were personal contacts, contacting firms through online details and professional institutions, etc. With all of this effort, our average success rate was less than 5 per cent. The main obstacles encountered were firms’ reluctance because of commercial sensitiveness and fear that the data could eventually be divulged to their competitors or end up in the public domain. However, some firms agreed mainly because of the written assurances of confidentiality and anonymity in reporting the study; reputation of the researchers’ academic institution; gatekeepers who spoke to their colleagues on our behalf; academic purpose of the study; and a feedback report which was promised in return for access to the case studies. Although the access through personal contacts is by far the easiest, it is not always possible. Researchers can approach firms as complete strangers, especially in a foreign country, and that could make the firms more likely to assist the research.
Resumo:
BACKGROUND: Intracoronary application of BM-derived cells for the treatment of acute myocardial infarction (AMI) is currently being studied intensively. Simultaneously, strict legal requirements surround the production of cells for clinical studies. Thus good manufacturing practice (GMP)-compliant collection and preparation of BM for patients with AMI was established by the Cytonet group. METHODS: As well as fulfillment of standard GMP requirements, including a manufacturing license, validation of the preparation process and the final product was performed. Whole blood (n=6) and BM (n=3) validation samples were processed under GMP conditions by gelafundin or hydroxyethylstarch sedimentation in order to reduce erythrocytes/platelets and volume and to achieve specifications defined in advance. Special attention was paid to the free potassium (<6 mmol/L), some rheologically relevant cellular characteristics (hematocrit <0.45, platelets <450 x 10(6)/mL) and the sterility of the final product. RESULTS: The data were reviewed and GMP compliance was confirmed by the German authorities (Paul-Ehrlich Institute). Forty-five BM cell preparations for clinical use were carried out following the validated methodology and standards. Additionally three selections of CD34+ BM cells for infusion were performed. All specification limits were met. Discussion In conclusion, preparation of BM cells for intracoronary application is feasible under GMP conditions. As the results of sterility testing may not be available at the time of intracoronary application, the highest possible standards to avoid bacterial and other contaminations have to be applied. The increased expense of the GMP-compliant process can be justified by higher safety for patients and better control of the final product.
Resumo:
High strength, high modulus carbon fibres are becoming increasingly important as high performance engineering materials. This thesis describes how they may be prepared by heat treatment from filaments spun from polyacrylonitrile and its copolymers. The chemistry of the first stages of heat treatment is very important in controlling the mechanical properties of the carbonised product. A cyclisation reaction has been found to be responsible for the relatively high thermal stability of pyrolysed polyacrylonitrile, but without oxidation the fibres degrade and fuse. An initial oxidation stage is, therefore, essential to the preparation of fibre of high orientation. The cyclised product of pyrolysis is probably a poly 1,4 dihydropiridine and oxidation converts this to aromatic structures, and cyclised structures containing carbonyl and other oxygenated groups. Oxidation is found to assist the carbon fibre preparation process, by producing a product which condenses at an earlier stage of heat treatment, before fusion can occur. Carbon fibre strength and modulus are dependent upon producing a highly oriented crystal structure. While oxidation of the polymer stabilises the fibre so as to prevent disorientation, further large increases in orientation, with a commensurate improvement in strength and modulus, can be obtained by stretching at temperatures above 1,700 °C. This process is analogous to the way fibre orientation is increased by the stretching of the precursor. A lamellar graphite structure can be created in high temperature fibre, by carefully controlling the degree of oxidation. This type of graphite can produce very high values of Young's modulus. More often, however, graphite fibre has a fibrillar fine structure, which is explicable in terms of continuous graphite ribbons. A ribbon model is the most satisfactory representation of the structure of carbon fibre, as it explains the mechanism of the development of long range order and the variation of Young's modulus with crystalline preferred orientation.