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The critical pH for passivation of steel balls during wet grinding of hematite ore was found to be 10.5. With slurry pH below this critical value, corrosion played a significant role in the total wear of steel and the wear was temperature dependent. Above this critical value, corrosion was prevented and wear of steel, mainly due to abrasion, was independent of grinding temperature. Potential measurements also indicated that steel balls were passive at pH 10.5. In the region of passivation, protection of steel by lime additions was 24–26 per cent and by silicate additions was 30–32 per cent over the temperature range 25°–65°C. Neither grinding temperature nor slurry pH had a significant effect on work done on ore as measured by the increase of minus 200 mesh ore during grinding.

Dark Tourism is a newly recognized niche tourism type that is first coined in 1996 by Lennon and Foley. This new term has attracted academicians and researchers globally. Till mid of 20th century, major work on dark tourism was limited to understanding its concept and giving it various names such as death tourism, black tourism, horror tourism, thanatourism, morbid tourism, and many more. After the mid-20th century, the focus of researchers was shifted to tourists’ psychology specifically on tourists’ motivation. Researchers suggested various motivational factors such as ‘curiosity of unusual,’ ‘education and learning,’ ‘historic interest,’ ‘inner purification,’ and ‘interested in death-related sites’ that influence tourists to seek dark attraction places. Recent research identified impact of dark places on visitors’ emotions and experiences. Some has argued that after visit tourists’ experience negative emotions such as depression or horror. While some suggested that dark tourism have positive emotion experience. This chapter is based on a secondary database, descriptive in nature, and aims to depict the motivation, purposes, and behavior of tourists toward dark attraction places that are linked to places of dark history.

This paper aims to create a new searchable 3D city model to help managers improve their decision-making.

This paper identifies data management basics and the key elements used in the new model design; it further analyzes five-city models, presents its findings and proposes analytical trends for the new model. It discusses the concepts underlying existing models, explains the benefit brought by the proposed model and demonstrates its robustness.

City systems can be interconnected, thanks to data digitization and the integration of new technologies into different management processes. Although there are several 3D city models available, none of those identified in this research can be queried for several sectors.

This model design can only be successfully realized in the presence of a public mandate. Potential limitations include information security risks and political non-acceptance.

The present work proposes a searchable and high performance model having the distinctive capacity to bring together city systems and perform real-time data analysis in order to extract important information needed to guide the city, and in the context of a global vision.

The 60 GHz unlicensed band is being utilized for high-speed wireless networks with data rates in the gigabit range. To successfully make use of these high-speed signals in a digital system, a high-speed analog-to-digital converter (ADC) is necessary. This paper aims to present the use of a common collector (CC) input tree and Cherry Hooper (C-H) differential amplifier to enable analog-to-digital conversion at high frequencies.

The CC input tree is designed to separate the input Miller capacitance of each comparator stage. The CC stages are biased to obtain bandwidth speeds higher than the comparator stages while using less current than the comparator stages. The C-H differential amplifier is modified to accommodate the low breakdown voltages of the technology node and implemented as a comparator. The comparator stages are biased to obtain a high output voltage swing and have a small signal bandwidth up to 29 GHz. Simulations were performed using foundry development kits to verify circuit operation. A two-bit ADC was prototyped in IBM’s 130 nm SiGe BiCMOS 8HP technology node. Measurements were carried out on test printed circuit boards and compared with simulation results.

The use of the added CC input tree showed a simulated bandwidth improvement of approximately 3.23 times when compared to a basic flash architecture, for a two-bit ADC. Measured results showed an effective number of bits (ENOB) of 1.18, from DC up to 2 GHz, whereas the simulated result was 1.5. The maximum measured integral non-linearity and differential non-linearity was 0.33 LSB. The prototype ADC had a figure of merit of 42 pJ/sample.

The prototype ADC results showed that the group delay for the C-H comparator plays a critical role in ADC performance for high frequency input signals. For minimal component variation, the group delay between channels deviate from each other, causing incorrect output codes. The prototype ADC had a low gain which reduced the comparator performance. The two-bit CC C-H ADC is capable of achieving an ENOB close to 1.18, for frequencies up to 2 GHz, with 180 mW total power consumption.

The purpose of this paper is to investigate perceived stressors and coping behaviours in student nurses on a pre-registration programme of study. Stress in student nurses has been identified with decreased emotional well-being and poor academic achievement. The significance of stress and coping behaviours in students during training has implications for education and practice.

The present study recruited 87 pre-registration student nurses in a cross-sectional design. Bivariate and multivariate analyses assessed the differences in field and year of study and the students’ perceived stress and coping behaviours.

The findings showed that stress is a significant issue in nurse training. Fifty-three per cent of the participants had levels higher than the mean. Interestingly, the present study found that high-perceived stress was associated with avoidance behaviours. The most common type of perceived stress and ranked by highest factor were from written assignments and a lack of professional skills and knowledge. Their peer group and everyday life activities were shown as potential ways of coping with stressors. Thus, it seems reasonable to focus support on decreasing avoidant and enhancing stress-reducing behaviours.

Psychological stress and coping behaviours must be considered together, as perceived stress is bound by the ability to ameliorate stress by managing helpful and unhelpful behaviours.

The findings may suggest that a potential benefit could come from the provision of helpful strategies such as peer group support and reduction of avoidant behaviours. Also, there seems to be a need for greater mental health literacy in dealing with stress during training.

The level of mental alertness among students who are in need of study in the preparatory year – Imam Abdul Rahman Bin Faisal University. The level of self-competence of female students who are in need of study in the preparatory year – Imam Abdul Rahman Bin Faisal University. To learn about the relationship between mental alertness and self-competence among students who are in need of study in the preparatory year – Imam Abdul Rahman Bin Faisal University.

The researchers used the experimental method by following the experimental design with two measurements, tribal and posterior, for two groups, one experimental and the other control, due to its suitability to the nature of this research. Research sample: the research community included female students stumbling in the scientific path of Rayyan, the second semester of the academic year 2020–2021 AD, where the researchers selected the research sample in a deliberate manner from the stalled students of 25 students and a random sample of 10 female students was withdrawn to conduct the exploratory study. The number of the basic research sample is 15 female students. Reasons for selecting the search sample: all of the sample members are female students stumbling in the scientific path of Al-Rayyan for the academic year 2020–2021 and all sample members agree to apply the research.

The researchers refer to this to the virtual psychological guidance program-specific objectives, as well as the follow-up of the scientific principles and principles and the legalization of the measurement tools used in the research and the diversity of the program within the parts of the program and the training sought to develop the ability to manage pressures and emotions and training in social skills, awareness and self-awareness and the use of exercises relaxation, breathing and modern self-help, as well as the use of different methods and techniques such as the method of dialogue, discussion, awareness of feelings and problem-solving, which led to a change in behavior and personal characteristics, which led to a change in behavior and personal characteristics, leading to the development of behavior and personal characteristics.

The study aims to design a hypothetical psychological counseling program as a method of health care and its effect on the level of mental alertness and the level of self-efficacy of students who have struggled to study at the Deanship of the preparatory year – Imam Abdul Rahman bin Faisal University. The researchers used the experimental approach and applied this study on a sample of 25 students from the students who failed to study at the Deanship of the preparatory year for the second semester of the academic year 2020–2021 AD and the most important results were that the psychological counseling program as a method of health care had a positive effect on improving the level of mental alertness and the level of self-efficacy among the students who had failed to study. There is a positive correlation between the level of mental alertness and self-efficacy of struggling students as a way of health care.

This case presents some of the entrepreneurial challenges faced by a female leader in the technology sector who conceived a new product based on her passion to help others especially those most disadvantaged.

Upon completion of this case study, students should be able to prepare supply chain and distribution analysis that considers ethics and sustainability, integrate philanthropic efforts as part of an organizational strategy and recognize strategies to promote equity within and beyond an organization.

Connie Stacey (she/her) is an entrepreneur and president of Growing Greener Innovations, an award-winning battery energy storage company based in Alberta, Canada, with a mission to end energy poverty globally. With the emergence of COVID-19 as a global pandemic in 2020, Stacey turned her attention to an innovation called Project Rescue, a ventilator that uses non-identifying patient vitals to track data. It serves as a pandemic early warning system, addressing two key challenges: pandemic data are prone to error, and real-time information is non-existent after the pandemic has spread. This new product was conceived based on her passion to help others, especially those most disadvantaged. This multi-faceted case focuses on the many challenges that Stacey and her team needed to address. The dilemma in this case centres on establishing supply chains amid a pandemic, as well as prioritizing the corporate social responsibility elements of philanthropy and equity within her organization (and beyond).

This case is appropriate for third- or fourth-year undergraduate or graduate-level students.

In addition to “call out boxes” throughout the case and teaching note, additional readings/links/videos are outlined below. (These supplementary materials, “Teaching Tips”, are included in the teaching notes as well.)

CCS 11: Strategy.

The value of the DeLone & McLean model for planning actions before IS design and implementation can guarantee its success.The value of the DeLone & McLean model for IS auditing in critical dimensions of project success, including both hard and soft elements.Information and information systems are essential organizational resources that must be viewed in an interconnected way with the rest of the organization's resources and capabilities that systemically guarantee the achievement of the export objectives.The role of management commitment in the success of voluntary Information Systems.

The case deals with Luis's decision to continue a Competitive Information System project. For his PhD research project, Luis designed and implemented an information system to support the export goals of the business school for which he worked. Three months later, the System obtained positive feedback and user satisfaction but deficient System usage levels. Luis does not know whether to continue with the project or not. If he decides to continue, further steps are needed to increase the System's use for contributing to the export goals.

The case is suitable for use with MBA students and executive education short courses.

Teaching notes are available for educators only.

CSS 5: International Business.

The objective of this study is to present a successful strategy to promote Korea as the logistics hub of Northeast Asia. Firstly, we introduce the necessity of a logistic hub strategy for Korea. In order to develop a successful strategy, we consider the 'free trade zone' model of the Netherlands and China. We develop a realistic and suitable model for Korea based on this Jree trade zone' model. Our proposal for a successful logistic hub strategy for Korea is the fulfillment of the following six objectives: 1) security of market accessibility, 2) improvement of the logistic system, 3) improvement of the education system, 4) improvement of the tax system, 5) assurance of labor market flexibility, and 6) development of an appealing living environment for foreigners.

This article aims to study a model of flame propagation in a nonhomogeneous medium with a p-Laplacian operator. The intention with such operator is to model the effects of slow and fast diffusion, that can appear in a nonhomogeneous media, depending on the pressure driven conditions. In addition, the authors introduce a general form in the reaction term, that introduces the flame chemical kinetics.

To introduce the governing equations, the authors depart from previously reported models in flame propagation, but the authors consider a new modeling approach based on a p-Laplacian operator.

The authors provide evidences of regularity and uniqueness of solutions. Afterward, the authors introduce profiles of stationary solutions based on the definition of a Hamiltonian for the newly discussed model. Eventually, the authors obtain exponential profiles solutions with the help of a scaling, that transforms the model into a nonlinear Hamilton–Jacobi equation.

The new model has not been previously reported in the literature. The authors consider that the mathematical properties of a p-laplacian (in particular the property known as finite propagation) is of inherent interest to model pressure drive flames with slow or fast diffusion. Indeed, the authors’ approach has the value of providing an operator that can fit better to model flame propagation. In addition, the authors introduce a general form of chemical kinetics, to make the authors’ model further general.