Stages Of Development Process Research Articles

Key relationship-based determinants of project performance in China

The aim of this paper is to investigate the relationship-based factors that affect performance of general building projects in China. Thirteen performance metrics that may be used to measure the success level of construction projects are defined and categorized into four groups namely cost, schedule, quality and relationship performance. Fourteen risks inherent in relationships and 16 tools expected to facilitate relationship building that may affect project success are identified. Data of different projects were collected in China via a self-administered postal survey. Multiple linear regression models are developed to help explain the variance in different performance metrics. It has been found that ten risks and nine tools have either positive or negative influence on project performance to some different extents and in different project development process stages. Detailed explanations are made, especially to those variables bearing unexpected signs. It is recommended that firms in the Chinese construction industry manage the relationship-based factors that are significant in the MLR models so as to achieve project success.

Large Scale Biginelli Reaction via Water‐Based Biphasic Media: A Green Chemistry Strategy.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Enhancing Fine Chemicals Process Chemistry: A Practical Approach

In the fine chemicals industry, development is driven by a constant strive for higher yields and selectivity of existing processes and faster development of new processes and products. Key constraints in process development in today's low-tonnage chemicals sectors (fine and effect chemicals) remain the time and cost spent obtaining data to identify and verify new processes. This often limits the amount of knowledge of the process chemistry acquired from any process development activity. In the present work, the capability of a simple high throughput experimental device is exploited to develop, apply and evaluate some laboratory-based tools to provide valuable insights into the process chemistry, especially in the critical early stages of process development. This paper discusses the experimental and modelling approaches (based on a model heterogeneous solid-catalysed acylation reaction) adopted to investigate a set of conditions that should deliver good process performance. The use of the experimental design and data reconciliation concepts in an integrated way to deliver a better process design is also demonstrated.

574. Early Stage Product Development to Scale-Up: Use of Mini-Fermentation System for Screening and Process Development of Plasmid DNA Products

Top of pageAbstract Introduction: As the number of gene therapy studies and trials has increased in the past few years, an ever-increasing demand for plasmid DNA-based products exists. In this expanding field of plasmid production, emphasis has always been placed on the quality and safety of the plasmid product. Much of the focus has been placed on increasing the expression of these products, while few focus on the early-stage screening and development of efficient plasmid production. The typical transition of a plasmid from research to the manufacturing group begins with shaker flask culture productions, which often yield little information on the cell growth and yield characteristics. Scale-up of these shaker flask-derived products has been difficult to achieve, and there is a need to translate the results from these cultures to lab scale and pilot or production scale. Adequate information of growth and yield characteristics for various plasmid products is important in the early developmental stage of any product. Method: We have successfully demonstrated the use of the Sixfors|[trade]| mini-fermentation system for the efficient screening of early-stage development products along with process development of plasmid DNA production and the ability to scale up the process to more than 100L. The Sixfors|[trade]| mini-fermenters, with a maximum working volume of 500mL, have been configured to mimic a large-scale fermenter with efficient control of dissolved oxygen. These fermenters were used for process development of plasmid DNA production. Their use has been established in the screening of bacterial strains and the optimization of fermentation media and process parameters using statistical experimental design techniques. Results: Using the mini-fermenter system, we were able to achieve early-stage predictability of the use of bacterial strains and growth conditions for growing a particular plasmid along with the scalability of fermentation conditions. The use of statistical design techniques for optimizing media formulations and process conditions resulted in the optimum process conditions in a limited amount of time with excellent reproducibility. The studies conducted to demonstrate the successful scale-up of the fermentation process indicated that the data obtained from the mini-fermenters are reproducible even at larger scales of operation. The use of this mini-fermenter system resulted in overall reduction of the time required for the completion of plasmid DNA production. Conclusions: The use of Sixfors|[trade]| has been shown as an excellent tool for early stage process development, including plasmid DNA screening studies. This method is far superior to performing early experiments with shaker flasks and is an ideal replacement for using these cultures for screening studies. The process using this Sixfors|[trade]| system has been tested in the lab scale (10L) and the pilot scale (100L) fermenters and has been shown to scale-up with excellent reproducibility.

Large scale Biginelli reaction via water-based biphasic media: a green chemistry strategy

An important stage in process development is kilo scale preparation of the target compound. For this reason, a procedure involving water-based biphasic reaction media has been developed for conducting some exothermic reactions on a large scale. This protocol is illustrated by the energy-efficient and rapid preparation of dihydropyrimidinones by a solvent-free, green chemistry procedure applied to the Biginelli reaction using p-toluenesulfonic acid as catalyst.

Epitaxial thickening of AIC poly-Si seed layers on glass by solid phase epitaxy

A novel method for producing high-quality polycrystalline silicon (poly-Si) films on glass by means of solid phase epitaxy (SPE) of evaporated amorphous silicon on aluminium-induced crystallisation (AIC) poly-Si seed layers is introduced. Optical transmission microscope, Raman, UV reflectance spectroscopy and cross-sectional transmission electron microscope measurements show consistently that a transfer of the crystal properties of the AIC poly-Si seed layer into the crystallised amorphous silicon layer has been achieved. A 1-sun open-circuit voltage of 337 mV is realised with a hydrogenated SPE/AIC p–n junction device, which is a promising result considering the early stage of process development. The SPE/AIC method appears well suited for the fabrication of poly-Si thin-film solar cells on glass and, due to the high crystal quality and the much larger average grain size, could lead to improved energy conversion efficiencies compared to Si solar cells made by solid phase crystallisation.

Detection and quantification of the human IgG4 half‐molecule, HL, from unpurified cell‐culture supernatants

The presence and absence of inter-heavy-chain disulphide linkages contribute to the existence of the tetrameric (H(2)L(2)) and half (HL) human IgG molecules, respectively. Reduced effector response in the human IgG4 subclass presents an alternative therapeutic platform in a monoclonal-antibody (mAb) development program. During the initial cell-selection stage, titres of the recombinant human antibody present in crude cell-culture supernatants are determined by ELISA, a technique requiring nanogram quantities of mAb. In the case of an IgG4 antibody, this material is represented mainly by the combination of the tetrameric (H(2)L(2)) and dimeric (HL) forms of the antibody. The determination of concentrations or ratios of tetramer and dimer usually requires at least one chromatographic purification step, and thus frequently this is evaluated later in the mAb development process when the number of potential clones has been reduced. In the present paper we describe a Western-blot-based method that detects and quantifies IgG4 half-molecules, HL, from crude cell-culture supernatants without purification so that H(2)L(2)/HL ratios can be included as a part of early clonal evaluation along with the screening of mAb titres. This method was demonstrated (1) to have a linear HL detection range of 0.5-10 ng, (2) to require microlitre volumes of culture and (3) to react specifically with human IgG4 produced from hybridoma and Chinese-hamster ovary cell cultures. Moreover, this protocol is applicable to evaluate and monitor potential H(2)L(2)/HL variations as a result of changes during the process-development stage of a mAb development program.

Yield learning and the sources of profitability in semiconductor manufacturing and process development

A numerical model that identifies the high-leverage variables associated with profitability in semiconductor manufacturing is presented. Varying the parameters of the model demonstrates that a rapid yield-learning rate determines profitability more than any other factor does. Factors such as ramping-up early, adding fab capacity, depressing the terminal fault density, and shrinking die size all yield diminishing returns. The model also suggests that developing a rapid problem-solving capability in the early stages of process development enables successful yield learning.

Microscopical studies of Arachis pintoi root nodule with special reference to bacteroids and oleosomes at different stages of plant growth and nodule development

Nitrogen fixation in legume root nodules are believed to be supported by the supply of carbon compounds derived from host cells. The presence of storage organelles such as oleosomes in the infected cells may have an advantage as a supplementary source of carbon and energy as has been suggested for peanut ( Arachis hypogaea) root nodules. The present investigation explores the development of symbiosis in a wild diploid species of Arachis in relation to the bacteroids and oleosomes. Microscopical observations at different developmental stages of nodule and host plant have revealed that oleosomes were present only during early stages of infection process and nodule development before the establishment of symbiosis, and during senescence. Oleosomes were absent in the infected cells of effective nodules of A. pintoi whereas similar cells in the nodules of other wild diploid species of Arachis ( A. batizocoi, A. duranensis) and tetraploid A. hypogaea show presence of oleosomes. Another interesting feature in this species was the reversion of spherical bacteroids into rod-forms within the confines of the senescent nodule tissue.

Gold process mineralogy: Objectives, techniques, and applications

The extractive metallurgy of gold is largely driven by mineralogical factors such as gold particle size; association with other minerals; coatings; presence of cyanicides, oxygen consumers, and preg-robbers; presence of refractory gold minerals; and locking of submicroscopic gold in sulfide and sulfarsenide mineral structures. Gold process mineralogy addresses all issues related to gold ore processing by the detailed study of an ore or a mill product. The methodology is widely used as a predictive tool in feasibility studies and during the process development stage, and as a trouble-shooting tool for mineral processing and hydrometallurgical operations.

Selection of inherently safer process routes: a case study

Increased public concern about safety issues and stringent environmental standards has led plant designers to consider inherently safer design. The term ‘inherently safer’ implies that the process is safe by its very nature and not externally constrained to be safe by the use of add-on systems and devices. Such opportunities for developing inherently safer process are highest in the early stages of design. Constraints such as time, lack of knowledge and inadequate inherent safety analysis tools are often cited as obstacles to development and implementation of inherently safer design. In this paper, we describe an inherent safety analysis methodology that can be applied in the early stages of process development. The methodology is based on an inherent safety index for comparing process routes and heuristics for identifying hazards and generating alternative designs. This methodology has been implemented as one module in iSafe, an intelligent system that automates inherent safety analysis. One key benefit of iSafe is substantial reduction in the time and effort required to perform safety analysis. Automation of the inherent safety analysis also makes it more thorough and detailed, minimizes or eliminates human errors, facilitates documentation and makes the study results available online for detailed safety analysis and review in the later stages of process design. The details of inherent safety analysis at the route selection stage are discussed in this paper and illustrated by comparing competing processes for acetic acid manufacture.

Assessing the importance of the development activities for successful new services: does innovativeness matter?

This article reports on the results of a research project into the development activities undertaken during the launch of 132 new financial services in Greece. According to the results, business analysis and marketing strategy formation as well as launch are the stages of the new service development process which influence the success of a new service irrespective, for the most part, of the degree of innovativeness that characterizes it. The significance of the other three stages of the development process varies depending the degree of innovativeness that characterizes the new service and the type of objective (financial or not) that management considers in order to evaluate its actual performance.

PH control in microwell fermentations of S. erythraea CA340: influence on biomass growth kinetics and erythromycin biosynthesis

The creation of microscale fermentation procedures could have significant benefits at all stages of fermentation process development from discovery through to process optimisation. For both microbial and mammalian fermentations, pH is a vital process parameter as it has a marked affect on cell growth rate, viability and product synthesis. In this work, we describe the influence of various pH control strategies on growth and erythromycin synthesis by Saccharopolyspora erythraea CA340 at the 7 l scale and show that the effects can be reproduced in pH-controlled microscale fermentations (thousandfold scale translation). At the 7 l scale the implementation of base only or full pH control (NaOH and H 3PO 4 additions) significantly increased both the maximum growth rate and biomass concentrations attained compared to fermentations without pH control. There was over a twofold increase in erythromycin biosynthesis and the ratio of erythromycin A (EA) to erythromycin C (EC) increased from 2:1 to 6:1 (base only pH control) to 11:1 (full pH control). In order to measure pH during microscale fermentations, a specially designed microtitre plate was built that allowed the insertion of a micro-pH probe into each well (total well volume 7 ml). This, allowed manual base only pH control to be implemented in microwell fermentations which enhanced both the maximum specific growth rate and the maximum biomass concentration. Total erythromycin synthesis and the ratio of EA:EC were also significantly enhanced. This work has demonstrated the benefits of implementing pH control in microscale fermentations and now allows the specification of an automated pH control system.

313 開発設計上流におけるシンキングCAEについて

313 開発設計上流におけるシンキングCAEについて

Process synthesis for reactive separations

The integration of reaction and separation in one single process unit proved to lead to enormous savings in capital as well as in operating costs. This paper provides a systematic framework to consider reactive separations in the early stages of process development. It highlights a process synthesis procedure guaranteeing that processes like reactive distillation, reactive crystallization, reactive extraction or reactive stripping will not be overlooked during conceptual flowsheet development. First step of this procedure is the analysis of the chemical reaction system. In case a separation of one or more products, by-products or solvents seems to be beneficial for the performance of the reactor the physical separation behavior of the components has to be checked. The chemical reaction, the physical separation and the design on the apparatus need a defined operation window. Only when an overlap of these windows can be identified a reactive separation process is feasible and might lead to advantages in the overall process performance. The paper finally demonstrates that the integration of reaction and separation in one unit does not necessarily lead to economic benefits as the overall performance of the total chemical process has to be considered.

Thermoplastic filament winding with online-impregnation. Part A: process technology and operating efficiency

Process combinations of filament winding with online-impregnation of fibre bundles have previously been widely neglected, due to the technical difficulties of impregnating a large number of slender filaments with a highly viscous thermoplastic melt. An innovative impregnation technology, called impregnation wheel, has been developed which allows to produce high quality impregnated tapes or tows at considerable speeds. Due to the specific characteristics of the technology it offers itself to be adopted for a process combination with filament winding. The realised process technology is described in detail. To assess the operating profitability of the novel processing routine a simple cost comparison calculation with filament winding utilising preimpregnated tapes was conducted. Even though in the early stage of process development a number of values could only be roughly estimated, the required minimum impregnation speed for economic production of a glass fibre reinforced model component was deducted.

Optimal blank shape design by the iterative sensitivity method

In order to realize net shape manufacturing of drawn parts, determination of the optimal blank shape plays a key role in the process development stage. The sensitivity method has many successful applications of the optimal blank design. In the method, the undeformed blank shape is modified iteratively by moving boundary nodes in the initial moving direction until the deformed shape satisfies a target shape. To determine the magnitude of the movement of the nodes, both the shape error measured at the deformed shape and the shape sensitivity defined by the effect of initial shape change on the final shape are utilized. To obtain shape sensitivity for each boundary node numerically, a couple of deformation processes has been analysed at each design stage with an original blank and offset blank. Drawings of the trapezoidal cup, cross-shaped cup and oil pan have been chosen as examples to verify the sensitivity method. Both the cross-shaped cup and oil pan are examples of complicated material flow during forming while the trapezoidal cup is of a simple flow. For every case the optimal blank shape has been obtained after only a few modifications without any predetermined deformation path. With the predicted optimal blank, a corresponding experiment has been carried out. The deformed shapes of the experiment almost exactly coincide with the desired target shape in every case. Through the investigation, the sensitivity method is found to be excellent in the blank design of arbitrary shaped drawing products.

Developing GSK's green technology guidance: methodology for case-scenario comparison of technologies

There is growing interest in introducing environmental, health, and safety considerations during early stages of process development to achieve sustainable processes and products. GlaxoSmithKline (GSK) has previously described the concept of a Green Technology Guide (GTG) within the broader context of its programs to move the company towards more sustainable business practices. The concept for the Green Technology Guide is a series of case-scenario comparisons that provide scientists and engineers with comparative environmental and safety information on technologies for operations commonly found in the pharmaceutical industry.

Integrated decision support system for waste minimization analysis in chemical processes.

The need to build and operate environmentally friendly plants has challenged the chemical industry to consider waste minimization or even elimination starting from the early stages of process development. A thorough waste minimization analysis requires specialized expertise and is laborious, time-consuming, expensive, and knowledge-intensive. This has caused a major technical barrier for implementing waste minimization programswithin the industry. Previously, we had reported a systematic methodology and a knowledge-based system, called ENVOPExpert, for identifying waste minimization opportunities in chemical processes. In this paper, we propose an integrated qualitative-quantitative methodology to identify waste minimization alternatives and assess their efficacy in terms of environmental impact and process economics. A qualitative analysis is first conducted to identify the sources of wastes and to propose alternatives for eliminating or minimizing them. Environmental impact of each alternative is then calculated by doing a quantitative pollutant balance. The capital expenditure required for implementing the alternative and the resulting plant operating costs are also calculated and used in the evaluation of the waste minimization alternatives. Through this, practical and cost-effective options can be identified. This methodology has been implemented as an integrated decision support system and tested using the hydrodealkylation process case study with satisfactory results.

The Creative Process in Virtual Teams

This study explored the creative process in virtual teams, groups of geographically dispersed organizational members who carry out the majority of their activities through information technology. Using a naturalistic paradigm, the study specifically investigated (a) how the creative process evolves in virtual teams, and (b) how virtual teams communicate while producing creative work. Through maximum variation sampling, 36 individuals from 9 teams were selected. One semistructured telephone interview was conducted with each participant. Team members also completed a background survey. Grounded theorizing was used to generate an in-depth understanding of the phenomena under investigation. Four stages of the creative process emerged-idea generation, development, finalization/closure, and evaluation. Communication methods specific to each stage are discussed. Three work design approaches used during the creative process emerged-the wheel, modular, and iterative approaches. Implications and areas of future research are addressed.