Impact Of Shrinkage Research Articles

Does shrinkage have an impact on urban livability? An empirical analysis from Northeast China

Urban shrinkage has emerged as a global socioeconomic development issue, presenting new challenges for countries in advancing the construction of livable cities. To investigate whether urban shrinkage has an impact on urban livability (UL), along with its underlying mechanisms and transmission paths, this study employed comparative inductive analysis and took Northeast China as a case for theoretical discussion and empirical validation. The results indicated that: (1) Shrinkage did have an impact on UL, which was dominated by negative effects and supplemented by positive effects. Furthermore, it exhibited characteristics of phased and dimensional heterogeneity, with significant spatial differentiation. (2) The impact of shrinkage on UL was essentially a comprehensive result of the interplay between the positive and negative effects arising from changes in urban development capacity and per capita occupancy caused by shrinkage. This process involved both variable transmission paths and stock transmission paths, jointly explaining the positive and negative shrinkage effects. This study provides a new perspective on rational cognition for coping with shrinkage effects and their generative logic, as well as theoretical insights for other countries around the world to optimize UL in shrinkage scenarios.

Rethinking population shrinkage in the Australian context: a new research agenda

ABSTRACT Whilst the study on the impact of shrinkage is well documented in North America and Europe, the effects of population-driven shrinkage on rural and regional communities in Australia is comparatively under-researched. This is despite existing literature on the volatility of population change in regional and rural Australia. Therefore, there is cause for establishing a typology of shrinkage in the Australian context, unpacking the different and complex economic, social and environmental causes and consequences, and therefore impacts, and establishing a framework for ongoing research. In this paper, we set out the rationale for this typology, indicating how population drivers are not only extensive, but further complicated by the as-yet-unknown impacts of COVID-19 and teleworking. Regarding policy solutions, we suggest that while mindsets are increasingly changing from a need to reverse population trends to, instead, embracing opportunities and alternative futures for many regional and rural Australian towns, we need to first establish a typology of population shrinkage that is reflective of the Australian context to ensure policy responses are locally appropriate. Practitioner pointers - Mindsets around planning policies on the impacts of population-driven shrinkage are beginning to shift towards understanding the specific socio-economic circumstances of the localised area and adopting appropriate policy instruments accordingly. - To support this nascent shift, establishing a typology of shrinkage that is reflective of the Australian context is key.

Numerical study on the influence of vehicle diameter reduction and diameter expansion on supercavitation

Previous studies mainly focused on the geometric effects of cavitators on supercavity. The vehicle shape, especially the tail size, considerably affects supercavity but is rarely studied. This paper presents numerical results on the tail expansion and shrinkage impact on supercavitation. Particular attention is given to the influence of tail smooth expansion, unsmooth expansion, and shrinkage on the cavity profile and jet flow re-entry. Several vehicle models are built to study the different phenomena of cavitation evolution to explore the influence mechanism of the vehicle tail shape on cavitation. The study shows that the cavity around the vehicle is primarily affected by the vehicle tail. For smooth expansion models, the reasonable expansion of tail diameter can reduce the upward movement of the back jet, but it will destroy the cavity induced by the cavitator. Compared with smooth expansion, the unsmooth models at the same expansion angle will induce a new re-jet flow at the corner. For tail shrink models, with the decrease in tail diameter, the tail re-jet flow will climb along the body, causing the separation and shedding of cavity.

Second-Generation P-Values, Shrinkage, and Regularized Models

Second-generation p-values (SGPVs) are a novel and intuitive extension of classical p-values that better summarize the degree to which data support scientific hypotheses. SGPVs measure the overlap between an uncertainty interval for the parameter of interest and an interval null hypothesis that represents the set of null and practically null hypotheses. Although SGPVs are always in the unit interval, they are not formal probabilities. Rather, SGPVs are summary measures of when the data are compatible with null hypotheses (SGPV=1), compatible with alternative hypotheses (SGPV=0), or inconclusive (0<SGPV<1). Because second-generation p-values differentiate between inconclusive and null results, their Type I Error rate converges to zero along with the Type II Error rate. The SGPV approach is also inferentially agnostic: it can be applied to any uncertainty interval about a parameter of interest such as confidence intervals, likelihood support intervals, and Bayesian highest posterior density intervals. This paper revisits the motivation for using SGPVs and explores their long-run behavior under regularized models that provide shrinkage on point estimates. While shrinkage often results in a more desirable bias-variance trade-off, the impact of shrinkage on the error rates of SGPVs is not well understood. Through extensive simulations, we find that SPGVs based on shrunken estimates retain the desirable error rate behavior of SGPVs that we observe in classical models - albeit with a minor loss of power – while also retaining the benefits of bias-variance tradeoff.

Multiple replication of hierarchical structures from polymer masters with anisotropy

The copy of structures in the same tone as the original asks at least for a double replication. Each replication generation will suffer from shrinkage of the replication material used, due to curing or thermal contraction. The impact of shrinkage is addressed in a basic study by simulation and experiment. The main replication materials investigated are OrmoStamp and SU-8. Presently, the preparation of anisotropic adhesion elements with hierarchical structures is investigated. The structures are micrometer-sized isolated pads with nanometer-sized self-aligned ripples (laser-induced periodic surface structures) on top. The initial structures are available as isolated photoresist patterns on Si. The double replication of this polymeric master raises questions with respect to its chemical and mechanical stability. The authors report an optimized replication process with an OrmoStamp intermediate template and a final replication in an elastomer. The anisotropic character of the so prepared hierarchical elastomeric adhesion elements is demonstrated by measurement.

Impact of shrinkage on crack width and deflections of reinforced concrete beams with and without steel fibres

Current recommendations by fib Model Code 2010 only consider the effect of shrinkage strains on long-term crack width calculations of reinforced concrete (RC) elements. However, shrinkage strains develop fairly early and can influence mean strains as well as short-term crack width and deflection calculations. This paper examines the effect of shrinkage strains on short-term deformations using experiments on eight RC beams, with and without steel fibres, at the age of 4–5 months. The results show that due to shrinkage, measured strains, deflections and crack widths are higher than expected for fully cracked sections. The MC-2010 predictive equation for crack widths is amended to account for shrinkage strains and induced curvatures. This work will lead to better design equations and less serviceability problems in RC structures.

Impact of RFID technology on inventory control policy

RFID application can improve operation performance in a supply chain by reducing or eliminating inventory misplacement and shrinkage. In this paper, we present a periodic review inventory model to investigate and characterize the multiperiod inventory control policies in both non-RFID and RFID cases when the firm encounters misplacement and shrinkage. The optimal inventory control policy is proved to be a two-control limit policy. The control limits in both the non-RFID case and the RFID case are analyzed and examined, while considering the impact of shrinkage and misplacement on inventory policies. A critical inventory level is determined to identify the relationship of higher inventory level control limits between the RFID case and the non-RFID case. An intensive numerical study with sensitivity analysis of selling price, misplacement rate, shrinkage rate, inventory recovery rate, and tag price is conducted. We find that when RFID technology is adopted, the inventory control policy in the RFID case is much more stable than that of the non-RFID case, as the misplaced inventory can be recovered perfectly and instantly for sale and the inventory shrinkage can be reduced by RFID technology. In addition, one of our intriguing findings is that when the shrinkage rate is below a threshold value which is independent of parameters, RFID application has no effect on inventory control policy if the misplaced inventory can be recovered in a timely manner by physical audit, which has not been revealed in previous studies.

Early volume variation of positive lymph nodes assessed by in-room mega voltage CT images predicts risk of loco-regional relapses in head and neck cancer patients treated with intensity-modulated radiotherapy

ABSTRACTBackground. We investigated the possibility to early identify non-responding patients based on FDG-PET positive lymph nodes (PNs) volume variation assessed with in-room images.Material and methods. Twenty-seven head and neck cancer patients with at least one pre-treatment PNs were retrospectively analyzed; they received 54 Gy, 66 Gy, 69 Gy in 30 fractions on precautionary lymph nodal (N), primary (T) and PET positive (BTV) planning target volumes (PTVs), respectively with Helical TomoTherapy (SIB approach). PNs volume changes during treatment were assessed based on megavoltage computed tomography (MVCT) used for image guidance as ratio between volumes at fractions 10/20/30 and at first fraction. Data on T, N and M relapses (rT, rN, rM) were collected for all patients. The difference of PNs volume changes, during treatment, between patients with versus without relapses was tested (Mann-Whitney test). The impact of shrinkage on the corresponding survival curves (Cox proportional-hazard regression), dividing between no/moderate versus large shrinkage (based on ROC curve best cut-off value) was also investigated.Results. Median follow-up was 27.4 m (3.7–108.9). The numbers for rT, rN, rM were 5, 4, 6, respectively. Differences in PNs shrinkage were found between patients with and without rT/rN at all considered timing [fr 20, rT: 0.56 vs. 1.07 (median), p = 0.06; rN: 0.57 vs. 1.25, p = 0.07]. Differences were lower for rM. Survival curves provide high hazard ratios (HR) between PNs changes and rT/rN at all considered timing [fr 20, rT: best cut-off = 0.58, HR 5.1 (95% CI 0.5–49.4), p = 0.12; rN: best cut-off = 0.98, HR 14.9 (1.6–142.9), p = 0.01].Conclusion. A limited shrinkage of PNs during treatment is associated with poorer outcome in terms of T/N relapses. The early variation of PNs observed on in-room images may provide useful information about the individual response with potential application in guiding an early adaptation of the treatment.

Swell Drying: Coupling Instant Controlled Pressure Drop DIC to Standard Convection Drying Processes to Intensify Transfer Phenomena and Improve Quality—An Overview

Increasing globalization is driving agricultural production in developing countries toward better recovery levels and high additional value. A great opportunity is thus offered to emerging economies. By adopting appropriate and improved methods that allow better preservation, transport, and storage and that conform to the rigorous requirements and standards of organoleptic and nutritional quality as well as stringent hygienic criteria, emerging economies can derive significant benefits. Drying of biological materials usually results in shrinkage. The impact of shrinkage is often highly prejudicial for both the function and use of these materials. On the one hand, shrinkage results in a sharp decrease in water diffusivity through the porous structure (for dehydration and rehydration processes). On the other hand, the compact structure of dried biological material is usually unsuitable in terms of organoleptic quality and is inadequate for grinding. Thus, it is becoming very important to include retexturing and structure-expanding processes in standard drying processes. To this end, the instant controlled pressure drop (DIC) technology has been proposed and successfully tested as a texturing process for partially dried materials, which should normally intensify the whole operation. The quality of the final product as well as the performance of the drying process can also be dramatically improved. Finally, for a large category of dried fruits and vegetables, and even freeze-dried materials, microbiological contamination and the presence of insects and larvae are serious problems. DIC technology can be used as an ultra-high-temperature treatment for a controlled decontamination. Such dried, expanded, and completely decontaminated products can be used as highly nutritional snacks. They can easily be ground to produce expanded granulated powders with excellent sensory, nutritional, functional, and textural properties.

Effect of Geometry of Rice Kernels on Drying Modeling Results

Geometry of rice grain is commonly represented by sphere, spheroid, or ellipsoid shapes in the drying models. Models using simpler shapes are easy to solve mathematically; however, deviation from the true grain shape might lead to large errors in predictions of drying characteristics such as moisture content (MC) and moisture gradients (MG). This research was undertaken to determine the impact of such shape considerations on prediction of drying characteristics. Impact of shrinkage of grains caused by drying was also investigated. Three separate mathematical models, each representing rice grain by sphere, spheroid, and ellipsoid shapes, were developed to describe the drying process. These models were solved by the finite element method using Comsol Multiphysics® simulation program. Drying simulations showed important differences in predictions of MC and MG in these three models. The sphere-shaped model predicted a slower drying than the spheroid- and ellipsoid-shaped models, whose MC predictions were similar. In all three models, maximum moisture gradients (MMG) were observed along the shortest axis in the bran region. During drying, MMG increases, reaches a peak, and then decreases. Magnitude and onset of peak of MMG were different in the three models. These differences in drying predictions among the three models make it important to use the appropriate shape to represent the rice grain in mathematical models. Ellipsoid shape, which closely resembles geometry of the rice grain, was found to be the most suitable. Reliable MG predictions from such ellipsoid-shaped models could be correlated to grain fissuring, which thereafter can be employed to optimize the drying process. The impact of shrinkage of rice grains during drying on model predictions is very small. In any drying simulation, maximum error due to neglecting shrinkage would be less than 5% of total moisture loss value.

CFD modelling of the fast pyrolysis of biomass in fluidised bed reactors: Modelling the impact of biomass shrinkage

The fluid–particle interaction and the impact of shrinkage on pyrolysis of biomass inside a 150 g/h fluidised bed reactor is modelled. Two 500 View the MathML sourcem in diameter biomass particles are injected into the fluidised bed with different shrinkage conditions. The two different conditions consist of (1) shrinkage equal to the volume left by the solid devolatilization, and (2) shrinkage parameters equal to approximately half of particle volume. The effect of shrinkage is analysed in terms of heat and momentum transfer as well as product yields, pyrolysis time and particle size considering spherical geometries. The Eulerian approach is used to model the bubbling behaviour of the sand, which is treated as a continuum. Heat transfer from the bubbling bed to the discrete biomass particle, as well as biomass reaction kinetics are modelled according to the literature. The particle motion inside the reactor is computed using drag laws, dependent on the local volume fraction of each phase. FLUENT 6.2 has been used as the modelling framework of the simulations with the whole pyrolysis model incorporated in the form of user defined function (UDF).

A research agenda for loss prevention

PurposeThe purpose of the paper is to draw attention to an area of research that has considerable potential for academic researchers in the disciplines of retailing and distribution studies.Design/methodology/approachThe methodology adopted was an overview of existing literature with a view to identifying possible trends in research in the area of loss prevention.FindingsThe paper identifies an extensive body of existing literature and provides an indication of areas for future research in loss prevention.Practical implicationsThe implications of these key issues are significant to the measurement of shrinkage in terms of the scope across the business from which shrinkage needs to be considered. This finding highlights the need to consider shrinkage as a systemic issue that extends across a business from design, through planning to operational execution. It also identifies the impact of shrinkage on increasing cost and depressing sales and considers the responsibility of management teams in addressing these matters.Originality/valueThis paper is an original discussion on the topic and thus of value to the academic community. It is also of value to the practitioner community as it highlights the importance of developing relationships with the academic community.

Heat transfer and kinetics in the pyrolysis of shrinking biomass particle

The impact of shrinkage on pyrolysis of biomass particles is studied employing a kinetic model coupled with heat transfer model using a practically significant kinetic scheme consisting of physically measurable parameters. The numerical model is used to examine the impact of shrinkage on particle size, pyrolysis time, product yields, specific heat capacity and Biot number considering cylindrical geometry. Finite difference pure implicit scheme utilizing tri-diagonal matrix algorithm (TDMA) is employed for solving heat transfer model equation. Runge–Kutta fourth-order method is used for chemical kinetics model equations. Simulations are carried out for radius ranging from 0.0000125 to 0.05 m , temperature ranging from 303 to 900 K and shrinkage factors ranging from 0.0 to 1.0. The results obtained using the model used in the present study are in excellent agreement with many experimental studies, much better than the agreement with the earlier models reported in the literature. Shrinkage affects both the pyrolysis time and the product yield in thermally thick regime. However, it is found that shrinkage has negligible affect on pyrolysis in the thermally thin regime. The impact of shrinkage reflects on pyrolysis in several ways. It includes reduction of the residence time of gases within the particle, cooling of the char layer due to higher mass flux rates of pyrolysis products and thinning the pyrolysis reaction region.