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The purpose of this paper is to construct an event-triggered finite-time fault-tolerant formation tracking controller, which can achieve a time-varying formation control for multiple unmanned aerial vehicles (UAVs) during actuator failures and external perturbations.

First, this study developed the formation tracking protocol for each follower using UAV formation members, defining the tracking inaccuracy of the UAV followers’ location. Subsequently, this study designed the multilayer event-triggered controller based on the backstepping method framework within finite time. Then, considering the actuator failures, and added self-adaptive thought for fault-tolerant control within finite time, the event-triggered closed-loop system is subsequently shown to be a finite-time stable system. Furthermore, the Zeno behavior is analyzed to prevent infinite triggering instances within a finite time. Finally, simulations are conducted with external disturbances and actuator failure conditions to demonstrate formation tracking controller performance.

It achieves improved performance in the presence of external disturbances and system failures. Combining limited-time adaptive control and event triggering improves system stability, increase robustness to disturbances and calculation efficiency. In addition, the designed formation tracking controller can effectively control the time-varying formation of the leader and followers to complete the task, and by adding a fixed-time observer, it can effectively compensate for external disturbances and improve formation control accuracy.

A formation-following controller is designed, which can handle both external disturbances and internal actuator failures during formation flight, and the proposed method can be applied to a variety of formation control scenarios and does not rely on a specific type of UAV or communication network.

To complete this case, students will need to access financial statements from the Securities and Exchange Commission’s webpage. The links are provided. Students will also need to review the conceptual framework that is typically covered in Intermediate 1 to respond to question 5.

This case is based on the three financial statement restatements that Weatherford International Ltd. made over an approximately 18-month period. The restatements were due to a fraud committed by manipulating the income tax accrual in the financial statements. The manipulation used was to overstate the amount of income used to calculate the dividend exclusion and then use a relatively high tax rate to calculate the resulting tax benefit. The tax rate used for the fraud was substantially more than Weatherford’s effective tax rate (ETR), which was a prominent part of the company’s strategic growth plan. The tax senior with the external auditors who reviewed the entry made for the dividend exclusion captured the inconsistency with the comment that “This [the entry] deserves a huh?” The case is intended for students in Intermediate 2, where financial statement restatements and their effect on the company’s financial statements are typically covered. During the years covered in this case, Weatherford was also under investigation for violations of the Foreign Corrupt Practices Act (FCPA). Weatherford’s FCPA violations included multiple instances of bribery, the inappropriate use of volume discounts, improper payments and kickbacks in the United Nation’s Oil for Food program. Weatherford received the eighth-largest fine in the history of FCPA violations (at that time) of $152m. Weatherford’s FCPA investigation expanded, and the company paid another $100m in fines for violations of sanctions law and export control law. This case focuses only on the fraudulent manipulation of the financial statements through the tax accrual and does not delve into the other investigations. However, the linkage between those investigations and the fraud in this case is Weatherford’s nonexistent internal controls.

This case was designed to be used in Intermediate 2 financial accounting classes to highlight financial statement restatements and review the conceptual framework and materiality. The students who used the case did not have difficulty with the tax aspect of the case. However, most of the students had taken one tax class previously or concurrently. If students have not had any exposure to tax, the instructor might want to walk students through the tax aspects of the case.

This paper aims to consider the relationship between urban events and urban public space, asking whether cities have enough space for events and whether events have enough space in cities.

Policy analysis surrounding events and festivals in the Netherlands is used to understand the dynamics of urban events, supported by content analysis of policy documents. A vignette of event space struggles in Amsterdam illustrates the contradictions of the event/space relationship.

The research identifies a policy shift in the Netherlands towards urban events from expansive, festivalisation strategies to defensive, NIMBYist policies. It exposes contradictions between protecting space as a living resource and the exploitation of space for regenerative purposes. Three future scenarios for urban events are outlined: conflict and competition, growth and harmony and digitalisation and virtualisation.

Develops scenarios for the future relationship between events and urban space.

Provides an analysis of the recursive spatial implications of the growth of the events sector for cities and the growth of cities for events.

Aero-engine exhaust plume length can be more than the aircraft length, making it easier to detect and track by infrared seeker. Aim of this study is to analyze the effect of free stream Mach number (M_∞) on length of potential core of plume. Also, change in infrared (IR) signature of plume and aircraft surface with variation in elevation angle (θ) is examined.

Convergent divergent (CD) nozzle is located outside the rear fuselage of the aircraft. A two dimensional axisymmetric computational fluid dynamics (CFD) study was carried out to study effect of M_∞ on potential core. The CFD data with aircraft and plume was then used for IR signature analysis. The sensor position is changed with respect to aircraft from directly bottom towards frontal section of aircraft. The IR signature is studied in mid wave IR (MWIR) and long wave IR (LWIR) band.

The potential plume core length and width increases as M_∞ increases. At higher altitudes, the potential core length increases for a fixed M_∞. The plume emits radiation in the MWIR band, whereas the aerodynamically heated aircraft surface emits IR in the LWIR band. The IR signature in the MWIR band continuously decreases as the sensor position changes from directly bottom towards frontal. In the LWIR band the IR signature initially decreases as the sensor moves from the directly bottom to the frontal, as the sensor begins to see the wing leading edges and nose cone, the IR signature in the LWIR band slightly increases.

The novelty of this study comes from the data reported on the effect of free stream Mach number on the potential plume core and variation of the overall IR signature of aircraft with change in elevation angle from directly below towards frontal section of aircraft.

This study aims to propose and evaluate the progress in the basic-pixel (a strategy to generate continuous trajectories that fill out the entire surface) algorithm towards performance gain. The objective is also to investigate the operational efficiency and effectiveness of an enhanced version compared with conventional strategies.

For the first objective, the proposed methodology is to apply the improvements proposed in the basic-pixel strategy, test it on three demonstrative parts and statistically evaluate the performance using the distance trajectory criterion. For the second objective, the enhanced-pixel strategy is compared with conventional strategies in terms of trajectory distance, build time and the number of arcs starts and stops (operational efficiency) and targeting the nominal geometry of a part (operational effectiveness).

The results showed that the improvements proposed to the basic-pixel strategy could generate continuous trajectories with shorter distances and comparable building times (operational efficiency). Regarding operational effectiveness, the parts built by the enhanced-pixel strategy presented lower dimensional deviation than the other strategies studied. Therefore, the enhanced-pixel strategy appears to be a good candidate for building more complex printable parts and delivering operational efficiency and effectiveness.

This paper presents an evolution of the basic-pixel strategy (a space-filling strategy) with the introduction of new elements in the algorithm and proves the improvement of the strategy’s performance with this. An interesting comparison is also presented in terms of operational efficiency and effectiveness between the enhanced-pixel strategy and conventional strategies.

The study set out to understand how the regional competitiveness index (RCI) in the department of Ancash related to the human development index (HDI) from 2008 to 2021. For a more complete understanding of the findings, each component or dimension of the RCI was analyzed. Ancash's HDI and its competitiveness index over a 14-year period were used as the population for this applied, longitudinal, descriptive-correlational study, which was based on secondary data extracted from the “Instituto Nacional de Estadística e Informática” (INEI) and business school of the Pontificia Universidad Católica del Perú (CENTRUM) statistical databases. Multiple linear regression was used to find the relationship. The research found a strong and positive correlation between regional competitiveness and human development between 2008 and 2021. No correlations were found between the HDI and the health, education, employment, or institutional dimensions of regional competitiveness, but direct and significant correlations were established between the economic environment and the HDI and between the infrastructure dimension and the HDI.

Science and technology are transforming our world in ways that have not been seen in a long time, and we live in a rapidly changing world. Despite these changes, as citizens of today, we must not lose sight of the reality that these changes even cause crises that must be managed in order to place ourselves in a true working environment that allows us to survive as employees despite these changes. The main objective of this research is to find the relationship between interpersonal competences and teacher performance in a sustainable university. The methodology used was the quantitative, nonexperimental approach, as the variables will not be deliberately manipulated. In order to verify whether or not there was a relationship between these variables, 84 teachers from the Universidad Nacional Santiago Antunez de Mayolo were surveyed to evaluate the variables under study. The results obtained show a direct and significant relationship (Spearman's Rho = 0.731) between the two variables. Through this research, it was possible to determine that teachers who have developed interpersonal competences have a better performance, while in the relationships between interpersonal competences and the dimensions of teacher performance, a positive correlation was obtained.

This study is concerned with the dynamics of the internal communications at Netflix following the release of The Closer and the public debate that followed, testing Netflix's long-standing reputation for promoting diverse content and supporting a progressive organizational culture.

Using the circuit of culture (CoC) as a theoretical framework, this study applies a case study approach to analyze internal communication and strategic public relations in addressing this crisis.

This study's findings illustrate that by failing to interpret two of the five moments of the CoC, production and identity, Netflix negated the very values that constitute its brand. These findings have implications for how public relations' long-standing focus on two-way symmetrical communication is problematic, especially in the workplace.

The findings situate how the exertion of power within an organization, particularly in moments of identity and production, problematize the role of two-way symmetrical communication within an organization in crisis.