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The purpose of this paper is to analyze the effects of scaling on the impact ionization and subthreshold current in submicron MOSFETs.

The effects of the various scaling techniques on a 100 nm device performances and the dependence of subthreshold current parameters on applied scaling technique are analyzed.

The results show that as the channel length is scaled down, multiplication factor increases slowly in the higher regime and rises rapidly in the lower regime of channel length. This result also justifies the inclusion of impact‐ionization effect on subthreshold current. The analysis shows that there is insignificant dependence of multiplication factor on the method of scaling. Similar variations in subthreshold current with channel length scaling have been observed in the analytical results for different scaling techniques.

The paper offers insight into the challenges of MOSFET scaling.

This paper aims to give some guidance on the selection of particle numbers per cell and the number of molecules per particle in the micro flow simulation by using DSMC method.

The numerical investigation is performed to study the effects of particle number per cell and the scaling factor of real molecules to a simulated particle on accuracy of DSMC simulation of two‐dimensional micro channel flows in the “slip flow” and “transition flow” regimes.

Numerical results show that both the particle number per cell and the scaling factor have effect on the accuracy of the DSMC results from the statistical error and the physical aspects. In the “slip flow” regime, a larger value of scaling factor can be used to obtain accurate results as compared to the “transition flow” regime. However, in the “transition flow” regime, much less number of particles in each cell can be used to generate accurate DSMC results as compared to the “slip flow” regime.

The present work is limited to the two‐dimensional case.

The results of this paper are very useful for the two‐dimensional micro flow simulation by DSMC.

The work in this paper is original and provides guidance on micro flow simulation.

Multiattribute ratings of country‐image are commonly obtained to study the influence of country‐of‐origin on product preference and purchase decisions. Usually, such ratings are obtained for products made in different countries in order to make comparisons across countries. However, recent research evidence indicates that, when individual respondents rate multiple entities (e.g., multiple countries), the ratings of a particular country can be affected by the other “contextual” countries included in the questionnaire. The purpose of this study is to examine, via a controlled experiment, the issue of measurement context effects in the measurement of country images. The hypotheses tested concern the stability of attribute‐based and entity‐based country image scaling and potential methods of reducing the vulnerability of multi‐entity scaling to entity context ‐‐ the use of an anchor entity and an insulator question set to increase country image measurement stability.

This paper aims to present experimental and finite volume method (FVM)-based simulation studies on the scaling effect on the capillary contact angle and entrant pressure for a three-dimensional encapsulation process of ball-grid array (BGA).

With the development of various sizes of BGA packages, the scaling effect of BGA model on capillary underfill (CUF) process is investigated together with the influences of different industrial standard solder bump arrangements and dispensing methods used as case study.

The experimental results agree well to the simulation findings with minimal deviation in filling time and similar flow front profiles for all setups. The results revealed that the capillary contact angle of flow front decreases in scale-up model with larger gap height observed and lengthens the encapsulation process. Statistical correlation studies are conducted and accurate regression equations are obtained to relate the gap height to the completion filling time and contact angle. CUF threshold capillary pressures were computed based on Leverett-J function and found to be increasing with the scale size of the package.

These statistical data provide accurate insights into the impact of BGA’s scale sizes to the CUF process that will be benefiting the future design of BGA package. This study provided electronic designers with profound understanding on the scaling effect in CUF process of BGA, which may be extended to the future development of miniature-sized BGA and multi-stack device.

This study relates the flow behaviour of encapsulant to its capillary contact angle and Leverett-J pressure threshold, in the CUF process of different BGA and dispensing conditions. To date, no research has been found to predict the threshold pressure on the gap between the chip and substrate.

This paper aims to introduce a new indicative parameter of filling efficiency to quantify the performance and productivity of the flip-chip underfill encapsulation process. Additionally, the variation effect of the bump pitch of flip-chip on the filling efficiency was demonstrated to provide insight for flip-chip design optimization.

The filling efficiency was formulated analytically based on the conceptual spatial and temporal perspectives. Subsequently, the effect of bump pitch on filling efficiency was studied based on the past actual-scaled and current scaled-up underfill experiments. The latter scaled-up experiment was validated with both the finite volume method-based numerical simulation and analytical filling time model. Moreover, the scaling validity of scaled-up experiment was justified based on the similarity analysis of dimensionless number.

Through the scaling analysis, the current scaled-up experimental system is justified to be valid since the adopted scaling factor 40 is less than the theoretical scaling limit of 270. Furthermore, the current experiment was qualitatively well validated with the numerical simulation and analytical filling time model. It is found that the filling efficiency increases with the bump pitch, such that doubling the bump pitch would triple the efficiency.

The new performance indicative index of filling efficiency enables the package designers to justify the variation effect of underfill parameter on the overall underfill process. Moreover, the upper limit of scaling factor for scaled-up package was derived to serve as the guideline for future scaled-up underfill experiments.

The performance of underfill process as highlighted in this paper was never being quantified before in the past literatures. Similarly, the scaling limit that is associated to the scaled-up underfill experiment was never being reported elsewhere too.

Digital business models are often designed for rapid growth, and some relatively young companies have indeed achieved global scale. However, despite the visibility and importance of this phenomenon, analysis of scale and scalability remains underdeveloped in management literature. When it is addressed, analysis of this phenomenon is often over-influenced by arguments about economies of scale in production and distribution. To redress this omission, this paper draws on economic, organization, and technology management literature to provide a detailed examination of the sources of scaling in digital businesses. We propose three mechanisms by which digital business models attempt to gain scale: engaging both non-paying users and paying customers; organizing customer engagement to allow self-customization; and orchestrating networked value chains, such as platforms or multi-sided business models. Scaling conditions are discussed, and propositions developed and illustrated with examples of big data entrepreneurial firms.

The efficacy of antiscaling treatments under simulated flow conditions was studied by chronoamperometric technique. The effect of temperature and concentration on the scale forming behaviour of different compounds were also studied under the simulated flow conditions. In order to simulate the flow conditions a rotating disc electrode technique was employed. The mechanism of antiscaling behaviour of different chemicals was studied through electrochemical impedance spectroscopy. It was found that the flow velocity affected the efficiency of antiscalants. Polymer based compounds follow the growth modification adsorption mechanism, while compounds like EDTA and phosphonate follow nucleation modification absorption/chemisorption mechanism. Temperature and concentration of the scale forming compounds have a significant role in the scaling process, particularly at the low concentrations.

This multiple case study research aims to identify the characteristics of scaling up SMEs in Chile for exploring how and why some entrepreneurship in the information technology (IT) sector are able to scale up and develop sustainable strategies, based on three consecutive years. The average sales of the companies during the last period analysed was around US$1,323,579, with an average annual growth rate of 66.7%. Scaling up SMEs may require several attributes to achieve positive revenue and develop effective high growth rates that allow them to succeed over several years.

To discern the phenomenon of entrepreneurship, the methodology of multiple case study research was conducted in three parts. The first was to define and design the research process, in which the study should settle the theory analysis and then show that research propositions and questions. The second part of the research was to prepare, collect and analyse the data through crafting instruments and data collection protocols as a source of evidence to conduct the pilot and multiple case study. In this stage, interviews were scheduled, transcribed, analysed and coded to explore how individual attributes may create a scaling-up entrepreneurial process for maintaining or developing high performance in the IT sector. The last part of the research concludes and validates the research propositions for the identification for potential attributes, which were obtained during the qualitative study.

Attributes were selected when 13 or more SMEs reported the importance of this initiative for the process of scaling up their SMEs. As a result of the data analysis, the empirical findings suggest on the importance of the academic background, budgetary control, negative entrepreneurial experiences, building teams, geographical expansion and first critical experience as key attributes for scaling-up. Additionally, the data propose that constructive entrepreneurial ecosystem and reforms financing markets and programmes are two additional components that could moderate the interaction between the scaling-up process and the achievement of rapid sales results as a key outcome measure.

The first limitation was the lack of consensus on the phenomenon of the scaling up of entrepreneurship. Information in Latin America and emerging countries is scarce, which also represents an opportunity for other researchers to deepen and validate the results reported here. Even though it was an attempt to understand the issue of environmental change, this additional limitation did not allow the evaluation of these adjustments over time that can positively or negatively drive the strategies corresponding to the evolution in each of the moderator variables.

Because of the characteristics of the sample in terms of size of the SMEs, industrial sector, location, culture, socio-economic environment and years of establishment of the company, the study cannot be generalised in terms of other industrial sectors or countries. The results of this research are also limited to SMEs in Chile, and to the extent that it can be applied to emerging countries IT sectors with similar sample characteristics, it must be done so with caution. Yin states that eight cases “are sufficient replications to convince the reader of a general phenomenon”.

Policymakers have the option to identify what skills and knowledge the entrepreneur requires to be trained to scale up their established ventures. In this context, they will also benefit from the empirical contribution of knowing what the restrictions that limit this process are, such as adverse tax systems and public strategies. Additionally, it is of public interest because no national records exist on the presence of theoretical terms.

Even though the literature promotes the present findings, it shows that there is an absence of empirical evidence in emerging economies to better comprehend which factors may affect the development process of scaling up entrepreneurship in the IT sector. Both deliberate and emergent strategic initiatives are necessary for the scaling-up process where six critical factors are the basis of the scaling-up. This empirical contribution for entrepreneurs will support the achievement of rapid and sustained sales results for scaling up their ventures.

This article introduces the best-worst scaling object case, a quantitative method of producing individual level models of heterogeneous perceptions, for use in behavioural decision making research in projects. Heterogeneous individual perceptions refer to observed or unobserved differences between individual perceptions that impact the outcome being studied. Individual level models of perceptions are important to account for the impact of heterogeneous perceptions on measurement tasks, so they do not become an unobserved source of variance that potentially biases research inferences.

An overview of individual heterogeneity is provided highlighting the requirement for individual level models in quantitative perception measurements. A literature review is then conducted of the quantitative methods and tasks used to measure perceptions in behavioural decision making research in projects and their potential to produce individual level models.

The existing quantitative methods cannot produce the necessary individual level models primarily due to the inability to address individual level scale effects, responses styles and biases. Therefore, individual heterogeneity in perceptions can become an unobserved source of variance that potentially biases research inferences.

A method new to project management research, the best-worst scaling object case, is proposed to produce individual level models of heterogeneous perceptions. Guidance on how to implement this method at the individual level is provided along with a discussion of possible future behavioural decision making research in projects.

This article identifies a largely unacknowledged measurement limitation of quantitative behavioural decision making research in projects and provides a practical solution: implementing the best-worst scaling object case at the individual level.

The purpose of this paper is to prepare poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid]s by two different routes. In the first route, poly(allyl amine-ran-acrylic acid)s were produced by radical copolymerization of a mixture of ally amine and acrylic acid, then converted into poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid]s by the Mannich reaction with a mixture of formaldehyde and phosphonic acid. In the second route, allyl amino bis(methylene phosphonic acid) monomer was synthesized and copolymerised with acrylic acid. The aim of this work is to produce low-molecular-weight copolymer with the low amount of nitrogen and phosphorous having better scale inhibiting performance than commercial low-molecular-weight poly(acrylic acid)s.

Poly(allyl amine-ran-acrylic acid)s were prepared by radical copolymerisation of a mixture of ally amine and acrylic acid, and the molecular weight of copolymers was regulated by using an effective chain transfer compound and the formed copolymer was reacted with a mixture of formaldehyde and phosphorous acid. Allyl amino bis(methylene phosphonic acid) monomer was prepared and then copolymerised with acrylic acid using radical initiators.

Poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] produced with both routes, especially low-molecular weight ones have better anti-scaling performance than low-molecular-weight commercial poly(acrylic acid).

By using an excess of formaldehyde and phosphonic acid, a limited increase in the conversion of amine groups of poly(allyl amine-ran-acrylic acid) to amino methylene phosphonic acid groups was achieved, so unreacted amine groups were always present in the structure of the final copolymers.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] may be used as a better anti-scaling polymer in industry.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] is an alternative polymer for scale inhibition in the water boilers.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] copolymers containing both carboxylic acid and amino bis(methylene phosphonic acid) are more effective anti-scaling additives than poly(acrylic acid)s in water boilers.