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The purpose of this paper is to present a numerical approach for investigating different phenomena during multiple liquid drop impact on air‐water interface.

The authors have used the coupled level‐set and volume‐of‐fluid (CLSVOF) method to explore the different phenomena during multi‐drop impact on liquid‐liquid interface. Complete numerical simulation is performed for two‐dimensional incompressible flow, which is described in axisymmetric coordinates.

During drop pair impact at very low impact velocities, the process of partial coalescence is observed where the process of pinch off is different than single drop impact. At higher impact velocities, phenomena such as bubble entrapment are observed.

In this paper, a new approach has been developed to simulate consecutive drop impact on a liquid pool.

This paper aims to study drop formation in piezoelectric industrial printheads during the inkjet printing processes. It presents how the piezoelectric printhead forms drops of nanoparticle ink and how the problems with different values of drop parameters may influence the printed pattern’ defects and quality.

A piezoelectric printhead with 128 nozzles was activated to operate in a controlled manner, and the droplets ejected from the nozzles were observed during falling and analysed in the printview system. The effect of varying the values of drop parameters on print quality and pattern defects has been analysed and discussed.

The obtained results allow the identification of the sources of the technological problems in obtaining repeatable performance drops with the desired properties, and indicate the importance of choosing the appropriate individually chosen strategy of controlling the printing for each individual application to get good-quality and free-from-defects patterns.

Because of the chosen research method (arbitrary selected printhead type and ink manufacturer), this study could have limited universality. Authors encourage the study of other kinds of piezoelectric heads or other conductive inks.

This study includes practically useful applications for users to improve the inkjet print quality.

This study presents results of original empirical research works on problems of the drops forming in the inkjet printing process, and finally, it identifies problems that must be resolved to disseminate this technology.

W.E.B. DuBois, in his 1903 collection of writings entitled The Souls of Black Folk, describes what he calls “The Veil,” which succinctly sums up the deadly and adverse experiences of African Americans in the US. With DuBois contemplations of a Veil under which US Blacks alone live and die as context, this paper takes a look at the modern condition of African Americans in the US, whether they continue to exist within DuBois Veil in modern times (twentieth and twenty-first centuries), and if so, to what extent. As a routine examination and inspection of the condition of Blacks in the US, focus is placed on black lives lost, beginning with an appraisal of their size in the US population overtime, and in comparison with other racial and ethnic groups in the US. US census data, health data collected from the Centers for Disease Control and Prevention, and crime data collected from the Federal Bureau of Investigation are examined to construct a composite of the condition of contemporary Blacks in the US as compared to other groups in the US, focusing attention specifically on the rates at which their lives are lost compared to others through infant mortality, low fertility rates, abortion, and high rates of homicide. This analysis concludes with a look at death from homicide before, during, and after the post-1990s drop in the crime rate.

The primary objective of this study is characterizing the anisotropic mechanical properties of corrugated cardboard and simultaneously simulating its drop cushioning dynamic effects under various drop conditions.

Static and dynamic tests were conducted on corrugated cardboard to obtain adequate experimental data in different directions. An effective anisotropic constitutive model is introduced by developing the honeycomb materials model in ANSYS LS-Dyna, and an effective approach is established toward effectively determining the material parameters from the test data obtained. The model is validated by comparing simulation results with experimental data from five drop conditions, including bottom drop, front drop, side drop, 30° side drop and edge drop. Additionally, simulations are conducted to study the cushioning performance of the packaging by dropping the corrugated cardboard at different heights.

The study establishes a fast and effective approach to simulating the drop cushioning performance of corrugated cardboard under various drop conditions, which demonstrates good agreement with experimental data.

This approach is of value for packaging protection and provides guidance for stacking of packaging during transportation.

Several studies have observed that stocks tend to drop by an amount that is less than the dividend on the ex-dividend day, the so-called ex-dividend day anomaly. However, there still remains a lack of consensus for a single explanation of this anomaly. Different from other studies, this dissertation attempts to answer the primary research question: how can investors make trading profits from the ex-dividend day anomaly and how much can they earn? With this goal, I examine the economic motivations of equity investors through four main hypotheses identified in the anomaly's literature: the tax differential hypothesis, the short-term trading hypothesis, the tick size hypothesis, and the leverage hypothesis.

While the U.S. ex-dividend anomaly is well studied, I examine a long data window (1975–2010) of Thailand data. The unique structure of the Thai stock market allows me to assess all four main hypotheses proposed in the literature simultaneously. Although I extract the sample data from two data sources, I demonstrate that the combined data are consistently sampled. I further construct three trading strategies – “daily return,” “lag one daily return,” and “weekly return” – to alleviate the potential effect of irregular data observation.

I find that the ex-dividend day anomaly exists in Thailand, is governed by the tax differential, and is driven by short-term trading activities. That is, investors trade heavily around the ex-dividend day to reap the benefits of the tax differential. I find mixed results for the predictions of the tick size hypothesis and results that are inconsistent with the predictions of the leverage hypothesis.

I conclude that, on the Stock Exchange of Thailand, juristic and foreign investors can profitably buy stocks cum-dividend and sell them ex-dividend while local investors should engage in short sale transactions. On average, investors who employ the daily return strategy have earned significant abnormal return up to 0.15% (45.66% annualized rate) and up to 0.17% (50.99% annualized rate) for the lag one daily return strategy. Investors can also make a trading profit by conducting the weekly return strategy and earn up to 0.59% (35.67% annualized rate), on average.

This study aims to determine the influence of bruise damage generated from the impact test on the physical, chemical and nutritional responses of tomato fruit.

The impact loading was applied from different heights. The impact energies for 20, 40 and 60 cm drop heights were 129.59, 259.18 and 388.77 mJ, respectively. The injured samples were kept for 48 hours at low (10 °C) and ambient (22 °C) storage temperatures. Weight loss, firmness, color, total soluble solids (TSS), lycopene and carotenoids were measured before the impact test (day 0) and after 48 hours of the impact and storage.

The drop height of 60 cm and storage at 22 °C showed the highest values in the bruised area. The impact from the 60 cm drop height significantly reduced weight, lightness, yellowness, hue, firmness, lycopene and carotenoids, particularly at 22 °C storage condition. Redness (a*) and color index (CI) showed a remarkable increase (p < 0.05) at 22 °C on tomatoes affected from the highest impact level (388.77 mJ) after 48 hours of storage. No pronounced significance was seen between TSS and drop heights. This study has confirmed that tomato bruising for a short-term storage period induces physiological changes at different storage temperature conditions.

The study can confirm the crucial role of inappropriate handling in increasing fresh produce loss within short-term storage. Also, this research can be considered as a guideline for transporters, handlers, processors, distributors and horticulture researchers in the fresh produce supply chain during postharvest operations.

“Social recovery” is a long-cited aim within the UK early intervention in psychosis (EIP) services; however, there is a lack of evidence regarding existing social recovery provisions and how these can be improved. This paper aims to evaluate an existing social drop-in facility within an EIP team, ran within the Birmingham and Solihull Mental Health NHS Foundation Trust, and highlight the potential benefits of delivering such services for people diagnosed with first episode psychosis.

Attendance and basic demographic statistics (age, gender and ethnicity of attendees) were collected over a period of 13 weeks. In addition, two semi-structured focus groups were conducted: one with EIP staff members (community psychiatric nurses and support workers) and the other with current service users, with both groups describing their satisfaction and experience of the drop-in facility and how it can be improved.

Inductive thematic analysis was used to analyse data from both focus groups, with six overarching meta-themes being identified: reflection, environment, emotional experience, recovery, activities and interactions. Service users and staff reflected that the drop-in facility was an asset to the service, although work could be done to improve overall attendance.

This paper explores how a social drop-in facility can provide a supportive, positive environment that aids recovery from psychosis for service users and improves working conditions for the EIP staff.

This study aims to investigate the conditions for the financial feasibility of an incentive-based model for self-drop or crowdsourced drop of the product to be returned at designated drop boxes (thereby ensuring a contactless process).

Constraint-based non-linear mathematical modeling was done for cost differential with and without crowdsourcing. This was analyzed against returns on investment for the installed infrastructure. Scenarios were looked into from the linear, iso-elastic and logarithmic demand functions to identify the optimal incentive policy. The results were further evaluated using “willingness to return” for customer willingness for product returns via drop boxes.

Crowdsourcing is viable when product returns are no more than 15%–20% of the overall products, with a logistics cost differential of 15%–25%. These were only viable when the product return incentive was within the range of 15%–20% of the product cost, as well as the penalty was in the range of 25 to 40% for wrong returns.

The findings are expected to aid the organizations in successfully designing product return policies while adhering to the post-COVID-19 norms, including contactless transactions and social distancing.

The study provides a look into the viability sensitivity of effective gains/profitability against the required level of service for returns, wrong returns, penalties and incentives for crowdsourcing in a developing country like India.

Research demonstrates that non-attendance at healthcare appointments is a waste of scarce resources; leading to reduced productivity, increased costs, disadvantaged patients through increased waiting times and demoralised staff. The purpose of this paper is to investigate non-attendance and implemented interventions to improve practice.

A mixed methods service audit took place in a primary care psychological therapies service. Existing service guidelines and reporting systems were reviewed. A cross-sectional design was used to compare a year’s cohort of completers of cognitive behavioural therapy (CBT) (n=140) and drop-outs (n=61).

Findings suggested contrasting guidelines and clinically inaccurate reporting systems. The overall service did not attend (DNA) rate was 8.9 per cent; well below rates suggested in the literature. The drop-out rate from CBT was 17 per cent. The most influential factor associated with CBT drop-out was the level of depression. The level of anxiety, risk ratings and deprivation scores were also different between completers and drop-outs. The main reasons given for non-attendance were forgetting, being too unwell to attend, having other priorities, or dissatisfaction with the service; again these findings were consistent with prior research.

A range of recommendations for practice are made, many of which were implemented with an associated reduction in the DNA rate.

The purpose of this paper is to focus on predicting the pressure drop in fluidized dense phase pneumatic conveying of fine particles through pipelines by modelling the solids friction factor in terms of non-dimensional parameters using experimental data of definite pipeline configuration. Finally, the model is to be tested for a different pipeline configuration.

Solids friction factor has been expressed in terms of certain non-dimensional parameters such as density ratio, solids loading ratio and mean particle diameter to pipe diameter ratio, and a certain number of coefficients and exponents. Experimental data of five conveying materials (two types of fly ash, two types of alumina and one type of cement meal) for a pipeline configuration of diameter 53 mm and length 173 m and another conveying material EPS dust for two pipeline configurations (69-mm diameter, 168-m long; 105-mm diameter, 168-m long) have been used to calculate the unknown coefficients or exponents of the mathematical model for solids friction factor.

The developed model gives the best results in predicting the pressure drop for the pipelines that are less than 173-m long, but the model shows a large error for the pipelines more than 173-m long.

Current research will be helpful for the researchers to model the process of pneumatic conveying through long distances.

The method will be helpful in conveying powder materials through long distances in cement or brick industry, alumina industry.

Fly ash piles over at the nearby places of thermal power plants. Pneumatic conveying is the best method for transporting the fly ash from the location of power plants to the nearby brick industries or cement industries.

Solid friction factor has been presented in terms of four non-dimensional parameters and evaluated the accuracy in predicting the pressure drop for two different pipeline configurations.