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The purpose of this paper is to investigate oil-gas slug formation in horizontal straight pipe and its associated pressure gradient, slug liquid holdup and slug frequency.

The abrupt change in gas/liquid velocities, which causes transition of flow patterns, was analyzed using incompressible volume of fluid method to capture the dynamic gas-liquid interface. The validity of present model and its methodology was validated using Baker’s flow regime chart for 3.15 inches diameter horizontal pipe and with existing experimental data to ensure its correctness.

The present paper proposes simplified correlations for liquid holdup and slug frequency by comparison with numerous existing models. The paper also identified correlations that can be used in operational oil and gas industry and several outlier models that may not be applicable.

The correlation may be limited to the range of material properties used in this paper.

Numerically derived liquid holdup and holdup frequency agreed reasonably with the experimentally derived correlations.

The models could be used to design pipeline and piping systems for oil and gas production.

The paper simulated all the seven flow regimes with superior results compared to existing methodology. New correlations derived numerically are compared to published experimental correlations to understand the difference between models.

The purpose of this paper is to propose a method to identify sources of variation in horizontal stabilizer assembly using FEA (finite element analysis) and PCA (principal component analysis).

The horizontal stabilizer is assembled by long and thin‐walled deformable aluminum components. Part‐to‐part assembly of these compliant components regularly causes difficulties associated with dimensional variations. Finite element modeling and PCA are employed to predict the propagation of variation from edge to horizontal stabilizer.

The variation analysis combined with pattern fitting method is demonstrated in a case study of the horizontal stabilizer assembly system and good performance is obtained. The results have shown that the FEA and PCA method has the capability of predicting, to an acceptable degree of accuracy, the overall geometrical variations propagation of the edges and trailing edge.

The results of this research will enhance the understanding of the compliant components deformation in assembly, and help to systematically improve the precision control efficiency in civil aircraft assembly.

There is a paucity of literature considering horizontal collaboration among grocery retailers, suppliers, and third‐party logistics (3PL) providers. This paper seeks to investigate benefits of and barriers to the use of fourth‐party logistics (4PL) management as a catalyst for horizontal collaboration.

Three suppliers, three logistics service providers (LSPs), and one grocery retailer participated in semi‐structured interviews for this exploratory qualitative study.

Large LSPs can establish 4PL management but the significant investment required to do so is a deterrent. Interviewees believed 4PL would negatively influence the grocery retailer‐supplier dynamic but simultaneously would provide key potential benefits. Retaining supply chain control means more to grocery retailers than cost efficiencies realised through horizontal collaboration.

Fierce competition among major grocery chains means that most are unwilling to participate in studies of their systems, which restricts the research scope.

Some stakeholders want deeper integration into grocery supply networks, and the 4PL model could apply to diverse sectors and circumstances. This study shows that barriers to such integration are created by power plays among lead stakeholders in grocery retailing that inhibit horizontal collaboration regardless of cost or other benefits.

The study investigates an under‐researched aspect of horizontal supply chain collaboration in the highly relevant retail grocery sector: a high volume, mass market industry that requires an enormous logistics infrastructure and highly embedded networks of relationships.

An indoor office space should not only provide adequate illuminance on horizontal planes but also cater to the physiological and psychological requirements of the occupants. This paper aims to describe a lighting simulation-based work conducted in Kolkata, India which modeled an indoor office to investigate the effects of variation in room surface reflectance combinations on user perception, mean room surface exitance (MRSE), average horizontal illuminance and overall uniformity of horizontal illuminance.

A fluorescent illumination system–based office space was modeled and retrofitted with tubular LED lamps in DIALux. Simulations were conducted for 16 different room surface reflectance combinations and a five-point Likert scale-type survey questionnaire was formulated to conduct a survey with 32 test subjects to assess the subjective preferability of each resultant light scene.

Simulation results demonstrate that the relationship between average horizontal illuminance and MRSE as well as between average horizontal illuminance and overall uniformity of horizontal illuminance, was statistically significant (p < 0.001). In the conducted survey, the resultant light scene arising out of the reflectance combination of wall:ceiling:floor = 60%:90%:20% was the most well-received one with 187 convinced agreements (“agree” and “strongly agree” responses).

This work found strong linear correlation between average horizontal illuminance and MRSE and between average horizontal illuminance and overall uniformity. A five-point Likert scale-type survey questionnaire with seven questions was formulated and validated with 32 test subjects (Cronbach’s alpha > 0.9295), which showed that the wall:ceiling:floor reflectance combination of 60%:90%:20% was the most favored choice.

The policy approach in Pakistan with regard to combating the informal economy has remained quite myopic and skewed in its reliance on measures informed by the rational economic-actor theory as opposed to the social-actor approach. Thus, this study attempts to evaluate and synthesise the two alternative policy approaches and formulate a more theoretically integrative understanding of the subject.

The authors gather data from 600 micro-entrepreneurs operating in the retail and wholesale sector of Lahore, Pakistan, which is then analysed using an ordered logit regression technique.

In contrast to more developed countries, the finding here is that higher perceived penalties have a highly significant and positive impact on the level of formality of Pakistani micro-entrepreneurs. The perceived risk of detection, meanwhile, has only a moderately significant impact on the micro-entrepreneurs level of formality. Likewise, the level of vertical and horizontal trust has a positive but moderately significant impact on the level of formality. Nonetheless, both the vertical and horizontal trust exhibit a very significant moderating effect on the relationship between the use of penalties and the level of formality, that is, the higher the level of trust that the micro-entrepreneurs have in the state and other businesses, the lower is the effectiveness of punitive measures.

Deterrence is an effective way to enhance the level of formality in the case of the Pakistani context. Nonetheless, the authors imply that without building trust, this overreliance on punitive and detective measures can actually be counter-productive. A combined and congruent (not sequential) use of voluntary compliance measures is thus warranted.

It is a unique attempt to evaluate and synthesise the global policy theorisations in a non-mainstream and antagonistic climate, such as Pakistan.

The purpose of this paper is to analyze the thermal and fluid dynamic behaviors of mixed convection in air because of the interaction between a buoyancy flow and a moving plate induced flow in a horizontal no parallel-plates channel to investigate the effects of the minimum channel spacing, wall heat flux, moving plate velocity and converging angle.

The horizontal channel is made up of an upper inclined plate heated at uniform wall heat flux and a lower adiabatic moving surface (belt). The belt moves from the minimum channel spacing section to the maximum channel spacing section at a constant velocity so that its effect interferes with the buoyancy effect. The numerical analysis is accomplished by means of the finite volume method, using the commercial code Fluent.

Results in terms of heated upper plate and moving lower plate temperatures and stream function fields are presented. The paper underlines the thermal and fluid dynamic differences when natural convection or mixed convection takes place, varying minimum channel spacing, wall heat flux, moving plate velocity and converging angle.

The hypotheses on which the present analysis is based are two-dimensional, laminar and steady state flow and constant thermo physical properties with the Boussinesq approximation. The minimum distance between the upper heated plate of the channel and its lower adiabatic moving plate is 10 and 20 mm. The moving plate velocity varies in the range 0-1 m/s; the belt moves from the right reservoir to the left one. Three values of the uniform wall heat flux are considered, 30, 60 and 120 W/m², whereas the inclination angle of the upper plate θ is 2° and 10°.

Mixed convection because of moving surfaces in channels is present in many industrial applications; examples of processes include continuous casting, extrusion of plastics and other polymeric materials, bonding, annealing and tempering, cooling and/or drying of paper and textiles, chemical catalytic reactors, nuclear waste repositories, petroleum reservoirs, composite materials manufacturing and many others. The investigated configuration is used in applications such as re-heating of billets in furnaces for hot rolling process, continuous extrusion of materials and chemical vapor deposition, and it could also be used in thermal control of electronic systems.

This paper evaluates the thermal and velocity fields to detect the maximum temperature location and the presence of fluid recirculation. The paper is useful to thermal designers.

The objective of this research is to systematically compare two methods of wicking test for evaluating the quality of the non-medical-mask fabric, i.e. its absorbency property at various conditions, using a design of experiment approach. This research also evaluates the suitability of several fabrics to be used for non-medical masks.

Horizontal and vertical wicking tests were selected to evaluate the absorbency property of five fabrics commonly used for the non-medical mask. The tests were performed at three temperatures and using two types of liquid. The design of experiment approach was employed to determine the relationship between the path length of liquid movement in fabric and type of test method, temperature and type of liquid.

Both vertical and horizontal wicking tests show the same order of fabrics according to their absorbency. The order is cotton twill, local cotton, Japanese cotton, Oxford and Scuba, where the first in the order has the lowest absorbency and the last has the highest absorbency. Based on the analysis of variance (ANOVA), the range of temperature and types of liquid employed in this research do not affect the path length of the liquid movement in the fabric.

This research proposes horizontal and vertical wicking tests as a practical tool to evaluate absorbency property of fabric for the non-medical mask. This research also presents a design of experiment approach to evaluate the effect of the test method, temperature and type of liquid on the path length of the liquid movement in the fabric.

The purpose of the study is to investigate how small- and medium-sized enterprises (SMEs) can effectively collaborate for eco-innovation using the business modes of innovation framework to emphasise three types of collaboration: “science, technology, and innovation” (STI), “learning by doing, using, and interacting” (DUI)-Vertical and DUI-Horizontal.

This analysis uses data from 838 SMEs in the Basque Country (2018–2020) to evaluate the effects of the three types of collaboration on eco-innovation. The authors employ a propensity score-based method to address potential bias associated with endogeneity in innovation studies.

The findings suggest that DUI-Vertical collaboration has a positive relationship with the development of product, process and marketing eco-innovation. Furthermore, DUI-horizontal collaboration is the most effective collaboration mode for SMEs, positively impacting their overall eco-innovation portfolio. Finally, STI collaboration is positively associated with product eco-innovation.

Policymakers should support SMEs by designing programmes that facilitate collaboration between competing firms to stimulate eco-innovation, but potential challenges of coopetition must be addressed. Rather than a generic, one-size-fit-all approach, SMEs' managers should identify the most appropriate partners corresponding to their specific eco-innovation goal, ensuring a more effective and targeted. Collaboration between science partners and SMEs should be reinforced by approximating the SMEs' needs more effectively.

This study contributes twofold. Firstly, the authors investigate whether the STI and DUI modes of innovation are determinant factors in the introduction of various types of eco-innovation. Secondly, the authors contribute to the literature on business modes of innovation by differentiating between DUI-Vertical (i.e. suppliers, customers and consultancy) and DUI-Horizontal (i.e. competitors) collaboration, thus highlighting the complexity of DUI collaboration forms.

Australian fiscal federalism possesses a greater degree of vertical imbalance than comparable federations elsewhere due to a concentration of revenue-raising powers at the level of the Commonwealth government and a concentration of expenditure functions at the state and local government levels. Efforts to deal with this problem have focused on intergovernmental grants. While substantial literature exists on the financial nexus between the Commonwealth and state governments, little research effort has been expended on the local government grants process. The present paper seeks to remedy this by documenting the evolution and role of the local government grants process.

Activist criminology advocates for social change by acting beyond the role of the academic, mainly through first-hand involvement in the field (Goyes, 2016). In this chapter, the author offers a longitudinal reflection on the researcher’s positionality, epistemology and methodology from the personal experience since their first research project, in 2019. During this project, the author started having cooperation with the Liberi Nantes migrants’ sports centre, now a community centre in Rome’s working-class suburb. This sparked her first reflections on activist criminology and how to embed it in her research approach and practice. The initial cooperation evolved in the ongoing and evolving collective ‘conversational integration’ project, which aims at overcoming the notion of integration as one-sided assimilation, working on addressing the diverse needs of the local community through a bottom-up governance initiative. This chapter is to be intended as a checkpoint in their growth within activist criminology and it hopefully serves to spark questions, suggestions and a push to form a solid network of activist academics that can help in fostering social change outside of the neoliberal agendas of academia.