Boycott Effect Research Articles

Who bears the cost of nationalism? A spatial analysis on the unintended spillover effects of boycotts

Who bears the cost of nationalism? A spatial analysis on the unintended spillover effects of boycotts

Pengaruh Boikot Besar-besaran Produk Amerika terhadap Peningkatan Jumlah Pengangguran di Indonesia

This research aims to analyze the impact of a large-scale boycott of United States products on the increase in unemployment in Indonesia. The boycott was driven by political tensions and controversial trade policies. Using quantitative analysis with secondary data from the Central Statistics Agency (BPS), company financial reports, and labor market surveys, the research shows a significant impact on sectors dependent on United States products and investments. Declines in sales and production in affected companies led to layoffs and higher unemployment rates. The impact was more pronounced in regions with concentrated industries related to American products. The study concludes that the boycott contributed to higher unemployment in Indonesia, with varying impacts across sectors and regions. These findings suggest important implications for policymakers in mitigating the economic effects of boycotts and highlight the need for economic diversification to reduce reliance on specific imported products.

Approaching Effective Differential Centrifugal Fractionation by Combining Image Analysis with Analytical Ultracentrifugation.

Centrifugation is one of the most commonly used methods for separation in biology and chemistry. However, effective fractionation is not always easy to obtain, as preparative centrifuge experiments are mostly conducted in an empirical way, even when it is guided by the quantitative results from analytical ultracentrifuge (AUC). Very few works have been performed to enhance the fractionation resolution of the differential centrifugation method in a swing-out rotor. This is primarily due to the absence of a characterization tool for sedimentation in the preparative centrifuge. In this study, we utilized image analysis to map the particle concentration distribution throughout the preparative centrifuge tube, revealing an unexpected and abnormal sedimentation process. By characterizing the sedimentation coefficient distributions of the fractionated product via AUC, we demonstrated that the overall sedimentation efficiency in a swing-out preparative centrifuge was significantly reduced. Furthermore, effective fractionation was confined to the intermediate phase of the entire sedimentation process. We propose that the mechanism here is a combination of the inverse Boycott effect and droplet sedimentation. The actual sedimentation process within a preparative centrifuge can be described by modifying the Lamm equation phenomenologically, which simply results in an effective sedimentation coefficient. Our work builds a foundation for determining the optimal preparative centrifugation conditions for various systems.

Study on the effect of container tilt on the falling speed of suspended particles in gravity field

The boycott effect is widely used in wastewater purification, drinking water purification, and mixture treatment in industry and manufacturing. In this paper, we analyze the settling velocity of particles in the clear water and suspended zones, and investigate the reasons for the tilting angle of the vessel to accelerate the settling velocity of particles. This paper uses video tracking software to analyze the settling velocity of particles in the experiment and draws conclusions.

High-order moving immersed boundary and its application to a resolved CFD-DEM model

The sharp interface immersed boundary method (IBM) is a powerful tool to simulate the flow around moving objects. This paper extends this method to simulate the motion of particles immersed in a fluid. We introduce a new implicit coupling scheme between the solid and fluid phases, verify the high–order of convergence of the scheme, and validate it using four cases. The fluid dynamics is simulated using a streamline upwind Petrov–Galerkin and pressure-stabilizing Petrov–Galerkin (SUPG/PSPG) stabilizations. The particles’ dynamics and contact are solved using Newton’s second law of motion and a soft sphere contact model derived from the discrete element method. The first validation case is the sedimentation of a lone particle with a Reynolds number smaller than 32. The second validation case is the rise of a positively buoyant particle at a high Reynolds number (2500). The third validation case demonstrates the stability of the scheme when particles are in contact and exhibit the classical drafting, kissing, and tumbling (DKT) behavior. Finally, we use the scheme to study the Boycott effect with a larger number of particles (64) to show the stability of the scheme in cases with numerous particle–particle and particle–wall contacts.

Study on the Particle Precipitation Phenomenon Based on the Boycott Effect

There is a well-known Boycott effect in particle precipitation. In order to further study the Boycott effect, this passage first analyzed the force on the particle, drew a diagram of the liquid flow consistent with the actual situation, and analyzed its settlement process from the perspective of dynamics. Based on the PNK theoretical model, this passage derived the proportional relation function between the average settling velocity and the vertical settling velocity , and obtain the relationship between the settling velocity and several variables. These variables include particle concentration range, particle radius, solvent viscosity coefficient, initial solvent volume concentration, container tilt angle, etc. According to this formula, passage designed related experiments to analyze the conditions of settlement strengthening effect, so as to further clarify the applicable conditions of settlement strengthening effect. It can be seen from the passage’s work that the experimental data is in good agreement with the theoretical value, which proves that this passage’s theory is very valuable, and this work also provides a certain reference value for industrial sewage settlement and river sand treatment.

Music Box-Inspired Semi-Automatic Hematocrit Validation Device.

A high hematocrit (HCT) level is strongly associated with the risk of cardiovascular disease. For early diagnosis of cardiovascular disease, it is vital to regularly measure the HCT, which is typically achieved by centrifuging a blood sample to measure the percentage of red blood cells. However, the centrifugal modalities are usually bulky, expensive, and require a stable electric input, which restrict the availability. This research develops a semi-automatic and portable centrifugal device for HCT measurement. This torque-actuated semi-automatic centrifuge, which we call the tFuge, is inspired by a music box, allowing different operators to generate the same rhythm. It is electricity-free and can be controlled based on a constant torque mechanism. Repeatable test results can be received from among different users regardless of their age, sex, and activity. With the assistance of the Boycott effect on the tFuge, we proved that the HCT level is in high linearity to the length of the sedimentation of the blood cells in a tube (R2 = 0.99, sample HCT range 10-60%). The tFuge takes less than 4 min and requires no more than 10 μL of blood that can be obtained by a less-invasive finger prick to complete the testing procedure. Calibrated gradient numbers are printed onto the rotation disc for instant HCT results that can be read by the naked eye. We expect this proposed point-of-care testing device possesses the potential to replace the microhematocrit centrifuge in the regions with limited resources.

A theoretical framework to determine the optimal centrifugation angle for separation of plasma from blood samples

The separation of blood plasma by centrifugation can be accelerated by placement of the sample at an angle relative to the direction of the centrifugal force. This geometric effect, which has been known for a century, is due to the Boycott effect, while the enhanced sedimentation of red blood cells (RBCs) in tilted vessels can be attributed to buoyancy-induced convection. Moreover, flow instability would invalidate the traditional predictive model and weaken separation enhancement. While current model considers only the geometric effect, by considering the buoyancy-induced convection and flow instability, we devise a model for the first time enabling the prediction of the optimal tilt angle to achieve the highest separation efficiency. A comparison of our theoretical prediction with the available experimental data shows good agreement. A sensitivity analysis is also conducted to investigate the influence of variation in blood samples on the physical parameters.

The Competitive Effects of Consumer Boycotts

The Competitive Effects of Consumer Boycotts

Recursive Settling of Particles in Shear Thinning Polymer Solutions: Two Velocity Mathematical Model.

Processing of the available experimental data on particles settling in shear-thinning polymer solutions is performed. Conclusions imply that sedimentation should be recursive, since settling also occurs within the sediment. To capture such an effect, a mathematical model of two continua has been developed, which corresponds to experimental data. The model is consistent with basic thermodynamics laws. The rheological component of this model is a correlation formula for gravitational mobility. This closure is justified by comparison with known experimental data available for particles settling in vertical vessels. In addition, the closure is validated by comparison with analytical solutions to the Kynch one-dimensional equation, which governs dynamics of particle concentration. An explanation is given for the Boycott effect and it is proven that sedimentation is enhanced in a 2D inclined vessel. In tilted vessels, the flow is essentially two-dimensional and the one-dimensional Kynch theory is not applicable; vortices play an important role in sedimentation.

No Beer No Friends: Quantifying the Effect of the Beer Boycott*

We study the impact of the boycott on Japanese products, initiated in July, 2019, in the Korean beer market. First, sales of japanese beer decreased by more than 70 percent during the 14‐month boycott period in the data. Second, the decrease in Japanese beer sales mostly reflected an increase in domestic beer sales. Lastly, the intensity of the boycott's effect has remained strong and stable despite a substantial decrease in traditional media coverage since the outbreak of the boycott movement. Our empirical findings suggest that political tensions can change market outcomes and negatively affect international trade for an extended period.

A simple and efficient parallel immersed boundary-lattice Boltzmann method for fully resolved simulations of incompressible settling suspensions

This study presents an efficient and parallel fully resolved direct numerical simulation (FR-DNS) of settling suspensions on multiple CPU cores based on the boundary-thickening direct forcing immersed boundary method (BTDF-IBM) and incompressible lattice Boltzmann method (LBM). The simple BTDF-IBM is used to meet the no-slip and no-penetration conditions on particle boundaries, and the incompressible LBM is used to achieve the capability of large pressure fluctuations in suspensions. In addition, a theoretical force model is used to compensate for the unresolved lubrication force between the two approaching particles. A swap strategy for the streaming step is used to reduce the memory storage of the LBM particle density functions to half. A distribution and communication strategy is proposed to handle the IBM computing and complete the immersed boundary (IB) force of the particles residing in the interface region between adjacent subdomains. The developed BTDF-IBM-LBM solver “PFlows” can simulate large particle-laden flows with more than O(106) particles and with a particle volume fraction of up to 0.4. An almost linear parallel speedup and efficiency of higher than 0.8 are obtained by testing three-dimensional (3D) cases (up to 1.0 billion fluid grids and 0.45 million particles) and two-dimensional (2D) cases (up to 1.2 billion fluid grids and 2.39 million particles). Finally, the framework is applied to three large-scale real simulations involving 50,000 particles settling in 2D and 3D bounded and unbounded domains for qualitative and quantitative validations. The particle settling behaviors and disturbed complex fluid flows in the vertical channel are demonstrated. The Boycott effect in the inclined channel is uncovered by a new mechanism that combines particle sliding at the lower sidewall with fluid convection in the upper region. The hindered settling of particles in the 3D periodic domain, which is affected by the strong particle-fluid hydrodynamic interactions and particle-particle many-body interactions at a high solid volume fraction, are analyzed. The complex behaviors and statistical characteristics of the suspensions are preliminarily revealed and analyzed, which demonstrates the prospective capability of the present framework for FR-DNS of large-scale 2D and 3D suspension flows that are relevant to many industrial applications by IB-LBM.

Dense Suspension Flows: A Mathematical Model Consistent With Thermodynamics

Abstract We address the flows of dense suspensions of particles within the framework of two-velocity continuum. Thermodynamics of such a continuum is developed by the method suggested in the papers of Landau and Khalatnikov. As an application, we consider the convective settling problem. We capture the Boycott effect and prove that the enhanced sedimentation occurs in a tilted vessel due to vortices. We do not call on additional interphase forces like the Stokes drag, the virtual mass force, the Archimedes force, the Basset-Boussinesq force and etc. Instead, we apply a generalized Fick's law for the particle mass concentration flux vector.

Hole-Cleaning Fibers Improve Cuttings-Carrying Capacity

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 203147, “Investigating Hole-Cleaning Fibers’ Mechanism To Improve Cutting Carrying Capacity and Comparing Their Effectiveness With Common Polymeric Pills,” by Mohammad Saeed Karimi Rad, Mojtaba Kalhor Mohammadi, SPE, and Kourosh Tahmasbi Nowtarki, International Drilling Fluids, prepared for the 2020 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, held virtually 9–12 November. The paper has not been peer reviewed. Hole cleaning in deviated wells is more challenging than in vertical wells because of the boycott effect or the eccentricity of the drillpipe. Poor hole cleaning can result in problems such as borehole packoff or excessive equivalent circulating density. The complete paper investigates a specialized fibrous material (Fiber 1) for hole-cleaning characteristics. The primary goal is to identify significant mechanisms of hole-cleaning fibers and their merits compared with polymeric high-viscosity pills. Hole-Cleaning Indices Based on a review of the literature, most effective parameters regarding hole cleaning in different well types were investigated. These parameters can be classified into the following five categories: - Well design (e.g., hole angle, drillpipe eccentricity, well trajectory) - Drilling-fluid properties (e.g., gel strength, mud weight) - Formation properties (e.g., lithology, cutting specific gravity, cuttings size and shape) - Hydraulic optimizations (e.g., flow regime, nozzle size, number of nozzles) - Drilling practices (e.g., drillpipe rotation speed, wellbore tortuosity, bit type, rate of penetration, pump rate) In this research, rheological parameters and parameters of the Herschel-Bulkley rheological model are considered to be optimization inputs to increase hole-cleaning efficiency of commonly used pills in drilling operations. The complete paper offers a detailed discussion of both the importance of flow regime and the role of the Herschel-Bulkley rheological model in reaching a better prognosis of drilling-fluid behavior at low shear rates. The properties of the fibrous hole-cleaning agent used in the complete paper are provided in Table 1. Test Method Two series of tests were performed. The medium of the first series is drilling water, with the goal of evaluating the efficiency of Fiber 1 in fresh pills. The second series of tests was per-formed with a simple polymeric mud as a medium common in drilling operations. Formulations and rheological properties of both test series are provided in Tables 4 and 5 of the complete paper, respectively.

Simulating particle settling in inclined narrow channels with the unresolved CFD-DEM method

Sediment settling in inclined fractures (channels with high aspect ratio) is studied numerically. Unlike the conventional Boycott effect, heterogeneous particle-clustering plumes are observed from the simulation results. Granular-induced Kelvin-Helmholtz and Rayleigh-Taylor instabilities are found to be the dominating mechanisms in this process. This work deepens the understanding of the Boycott effect in fractures, and provides various quantitative relationships of acceleration ratio versus inclination angle.

Maximizing recovery, grade and throughput in a single stage Reflux Flotation Cell

The Reflux Flotation Cell (RFC) utilises the Boycott Effect to decouple the overflow water flux from the gas flux, permitting in principle high product grade and recovery at a vastly higher volumetric feed flux. This study investigated this relationship between concentrate grade, recovery, and volumetric feed throughput using a single flotation stage and feed fluxes spanning 1–9 cm/s, well beyond that used in conventional flotation. Coal flotation tailings and hydrocyclone overflow provided convenient representations of “binary” feeds for the experiments, constituting liberated hydrophobic and hydrophilic particles. The results demonstrated robust recoveries through the preservation of the gas to feed flux ratio with increasing feed flux, while minimising the gas flux strengthened the capacity to maintain high product grade using inverted fluidization water as the wash water. Remarkably, a high product grade (low product ash%) was maintained over the extreme feed flux range by ensuring a net downwards flux of wash water delivered through the upper fluidized bed of bubbles. Coal Grain Analysis (CGA), an optical imaging technique, identified the maceral composition of the feed particles and validated, with close agreement, the RFC steady state separation performance. Indeed, under continuous operation the RFC data demonstrated an overall positive shift in performance relative to that of the standard tree flotation curve. The findings showed strong preservation of product grade and recovery using a single RFC stage, over a seven-fold increase in the feed flux relative to conventional flotation systems.

Gel Pills for Downhole Pressure Control during Oil and Gas Well Drilling

During drilling of petroleum or geothermal wells, unforeseen circumstances occasionally happen that require suspension of the operation. When the drilling fluid is left in a static condition, solid material like barite may settle out of the fluid. Consequently, the induced hydrostatic pressure that the fluid exerts onto the formation will be reduced, possibly leading to collapse of the borehole or influx of liquid or gas. A possible mitigation action is placement of a gel pill. This gel pill should preferably be able to let settled barite rest on top of it and still transmit the hydrostatic pressure to the well bottom. A bentonite-based gel pill is developed, preventing flow of higher density drilling fluid placed above it to bypass the gel pill. Its rheological behavior was characterized prior to functional testing. The designed gel pill develops sufficient gel structure to accommodate the settled barite. The performance of the gel was tested at vertical and 40° inclination from vertical. Both conventional settling and the Boycott effect were observed. The gel pill provided its intended functionality while barite was settling out of the drilling fluid on top of this gel pill. The barite was then resting on top of the gel pill. It is demonstrated that a purely viscous pill should not be used for separating a high density fluid from a lighter fluid underneath. However, a bentonite or laponite gel pill can be placed into a well for temporary prevention of such intermixing.

The Difference in Consumers’ and Company Employees’ Perceptions of Consumer Boycotts and Analysis of the Factors Affecting Boycott Participation

This study investigated how consumers and company employees differ in their perceptions of boycotts based on the co-orientation model. Regarding the reasons of boycotts, consumers take both consumer damage cases and unethical conduct equally seriously, while company employees take consumer damage cases more seriously than unethical conduct. Consumer perceptions of the necessity for boycotts was higher than company employees, while employees were more aware of the negative impact of boycotts than consumers. Based on the co-orientation model, we examined how consumers and employees estimate differences in their perceptions of boycotts. The results showed that consumers and company employees are not accurately aware of each other’s perceptions. Lastly, logistic regressions were conducted to identify the factors affecting three types of participation: online opinion expression, personal non-purchasing, and persuading other people to join the boycotts. The results showed that male consumers are more likely to participate in online opinion expression; consumer perceptions of effectiveness of boycotts and the perceived severity of consumer damage increase the likelihood of participation in online opinion expression. Consumer perceptions of the necessity of boycotts and their opinion leadership increased the likelihood of non-purchasing. Finally, consumers with higher opinion leadership and female consumers were more likely to encourage others to take part in boycotts. In addition, consumers are more likely to persuade others to join the boycotts if they have stronger beliefs that companies will not seriously consider consumer problems.

Optimizing the transport of cuttings with ecological drilling muds: application to directional well

This study is justified by the issues on site in directional well as blowouts, abnormal formation pressure, obstructions in the wellbore, inaccessible target locations caused by an obstacle (for example dome of salt) and the pollution of formations. The objective of this study is to optimize the hole cleaning in directional well with environmentally drilling muds. For this goal, different formulations of “green” drilling muds were tested for 4 inclinations of 10°, 20°, 30° and 40° compared with a horizontal plane for modeling the vertical drill. The drilling muds used are water based with environmentally friendly products; this study tested two biopolymer-based formulations, which are the constants of the experiment. For the specific needs of drilling muds, different products as clay, weighting and potassium chloride were added to the based solution. The microstructure and quantification of the chemical content of biopolymers were examined with SEM–EDS (scanning electronic microscope and energy dispersive X-ray spectrometer). Rheological properties were evaluated with modular rheometer; biopolymer solutions exhibit a non-Newtonian behavior. The samples tested in this study are compliant with API standards. For a suspension of macroscopic particles in the non-Newtonian environment, the sedimentation velocity shows a rapid increase according to the angle value which is well known in macroscopic suspensions under the name of “Boycott effect”. The results showed the close link between the composition of the drilling mud and its ability to transport cuttings predictive for directional drilling.

Japanese‐brand auto sales in China under the shadow of oppositional sentiments

AbstractThis study uses the interstate political conflict in 2010 to study the impacts of oppositional sentiment on product sales of Japanese‐brand automobiles in China. By using the nationwide automobile registration data in China, we conduct difference‐in‐differences analysis and find direct evidence on Chinese consumers’ boycott of Japanese‐brand autos. It is individual buyers rather than business or government entity buyers that boycotted Japanese cars significantly. War memory, nationalist education, and protests contributed to the intensity of boycott activities, and the boycott effect was long‐lasting. Older‐generation buyers boycotted Japanese cars more significantly, but younger‐generation buyers living in cities with historical war experience or patriotic education bases boycotted Japanese cars more actively than their counterparts in other cities.