Operational Control Research Articles

Multifunctional nanorobot system in precise evaluation and manipulation of virus capsid

It is imperative to have high adaptive techniques for sensing and manipulating biological targets at the nanoscale. This necessity becomes particularly crucial when dealing with fragile living bio-organisms like viruses, where the expression of capsids is closely linked to viral functions and genome constitution. Therefore, the development of a comprehensive system for dissecting and measuring viruses holds significant implications for the pharmaceutical industry and drug manufacturing. Leveraging the sub-nanometer spatial resolution and controllable tip-cantilever architecture of atomic force microscopy (AFM), a probe-laser system has been integrated as a self-sensing robotic end effector. To address intrinsic challenges in AFM-based robotic systems such as the lack of real-time monitoring, low scanning rates, and nonlinear motion caused by piezoelectric actuators, an augmented reality robotic system has been implemented. This system incorporates stereoscopic vision, a haptic feedback controller, a position recovery scheme, and a real-time force control algorithm. The integration of these components enhances the system’s capability to accurately dissect virus capsids. Operators can now perform highly efficient nanoscale tasks with multidimensional perception, utilizing the combination of stereoscopic vision and haptic force control. The position correction during manipulation can achieve a frame rate of over 30 frames per second, imperceptible to the operator, enabling closed-loop operation control. By adopting the proposed nanorobotic system in virology studies, it becomes possible to achieve accurate manipulation and dissection of SARS-CoV-2 pseudovirus capsids, and derive multi-parametric properties such as structural integrity, protein fragment thickness, and adhesive forces. The established nanobot system and experimental results serve as a guiding platform for high-accuracy evaluation in drug manufacturing development.

Multi-mode operations of double-stator switched reluctance machine for electric vehicle

PurposeThe purpose of this paper is to introduce a double-stator switched reluctance machine (DS-SRM) for electric vehicles (EVs) and to propose multi-mode operations for this machine.Design/methodology/approachAnalysis of flux linkage distributions and torque characteristics using finite element method (FEM). Building a dynamic simulation model based on electromagnetic characteristics, mathematical equations and mechanical motion equations of the DS-SRM drive system. The paper proposes multi-mode operations (inner-stator excitation mode, outer-stator excitation mode and double-stator excitation mode) based on motor working regions. It also conducts simulation and experimental results to verify the effectiveness of the proposed multi-mode operations strategies and control schemes.FindingsThere is almost no electromagnetic coupling between the inner and outer stators due to the specially designed rotor structure and optimized windings polarity configuration. Analysis of flux linkage distributions and torque characteristics verified the independence of inner and outer stators. Proposal of multi-mode operations and corresponding control rules achieved the smooth switching between different modes.Originality/valueThe paper introduced the DS-SRM for EVs and proposed multi-mode operations, along with control rules, to optimize its performance. The specially designed rotor structure, optimized winding polarity configuration, and the proposed multi-mode operations contribute to the originality of the research.

Transaction Monitoring Effect on Profitability of Commercial Banks in Kenya

Commercial banks' performance is fundamental to the economy as providers of financial services. In offering this service, commercial banks are exposed to a range of risks that negatively affect financial position and ultimately influence profitability. Profitability is indicative of a bank's stability and potential for growth. Enhancing commercial banks' profitability contributes to shareholder return on investment. In June 2018, five banks were fined a total of Kshs. 392 million by the Central Bank of Kenya for breaching anti-money laundering regulations. Consequently, banks had to invest resources to improve their anti-money laundering measures. Consequently, raising operational and compliance overheads. This study sought to determine the effect of transaction monitoring on profitability of commercial banks in Kenya. The research employed an explanatory research design. The targeted population comprised all the thirty-nine regulated commercial banks as of December 31, 2021. The study period was eight (8) years (2014 to 2021). Respondents were chosen through purposive sampling. Primary data was gathered using structured questionnaires, while secondary data was derived from audited financial reports of commercial banks and the annual banking supervision report from the Central Bank of Kenya. Subsequently, the collected data underwent analysis employing descriptive statistics and regression analysis. The research results disclosed that transaction monitoring positively and significantly influenced commercial banks profitability. Consequently, bank managers should incorporate transaction monitoring into their operations to augment the overall efficacy to detect and report potentially suspicious activities, and to strengthen operational controls.

Integrated charging scheduling and operational control for an electric bus network

The last few years have seen the massive deployment of electric buses in many existing transit networks. However, the planning and operation of an electric bus system differ from that of a bus system with conventional vehicles, and some key problems have not yet been studied in the literature. In this work, we address the integrated operational control and charging scheduling problem for a network of electric buses with a limited opportunity charging capacity. Operational control is carried out through speed control of the vehicles and bus holding at the terminal. We propose a hierarchical control framework to solve this integrated problem, where the charging and operational decisions are taken jointly by solving a mixed-integer linear program in the high-level control layer. Since this optimization problem might become very large as more bus lines are considered, we propose to apply Lagrangian relaxation in such a way as to exploit the structure of the problem and enable a decomposition into independent subproblems. A local search heuristic is then deployed in order to generate good feasible solutions to the original problem. This entire Lagrangian heuristic procedure is shown to scale much better on transit networks with an increasing number of bus lines than trying to solve the original problem with an off-the-shelf solver. The proposed procedure is then tested in the high-fidelity microscopic traffic environment Vissim on a bus network constructed from an openly available dataset of the city of Chicago. The results show the benefits of combining the charging scheduling decisions with the real-time operational control of the vehicles as the proposed control framework manages to achieve both a better level of service and lower charging costs over control baselines with predetermined charging schedules.

An improved dynamic analytical model and the parameter sensitivity analysis of spherical stacking latent thermal energy storage devices

Thermal energy storage technology plays an important role on improving energy usage flexibility for the end users. The spherical stacking latent thermal energy storage devices inherits the advantages of direct thermal energy usage efficiency and simplified practical applications that received widely attentions. However, due to dispersed and multi-layer structural arrangement, the non-ignorable dynamic heat transfer process poses difficulties in the device design and operation control. In this study, an improved analytical model for predicting the transient heat transfer process of spherical stacking devices is developed. After verification, the parameter sensitivity analysis of the device is conducted by using the model. The results show that the dynamic change trend of thermal resistance is distinct for the melting and the solidification process. The developed model can dynamically predict the outlet temperature of heat transfer fluid and the heat transfer efficiency in a good agreement, and the prediction error of outlet temperature during solidification can reach −2.49 %–4.70 %. The correlation between sphere radius and heat transfer rate is negative and reaches a kind of high correlation above 0.8 for solidification process. The inlet temperature and the mass flow rate of heat transfer fluid are the most influential parameters for melting process.

OpenCell: A low-cost, open-source, 3-in-1 device for DNA extraction.

High-cost DNA extraction procedures pose significant challenges for budget-constrained laboratories. To address this, we introduce OpenCell, an economical, open-source, 3-in-1 laboratory device that combines the functionalities of a bead homogenizer, a microcentrifuge, and a vortex mixer. OpenCell utilizes modular attachments that magnetically connect to a central rotating brushless motor. This motor couples to an epicyclic gearing mechanism, enabling efficient bead homogenization, vortex mixing, and centrifugation within one compact unit. OpenCell's design incorporates multiple redundant safety features, ensuring both the device's and operator's safety. Additional features such as RPM measurement, programmable timers, battery operation, and optional speed control make OpenCell a reliable and reproducible laboratory instrument. In our study, OpenCell successfully isolated DNA from Spinacia oleracea (spinach), with an average yield of 2.3 μg and an A260/A280 ratio of 1.77, demonstrating its effectiveness for downstream applications such as Polymerase Chain Reaction (PCR) amplification. With its compact size (20 cm x 28 cm x 6.7 cm) and lightweight design (0.8 kg), comparable to the size and weight of a laptop, OpenCell is portable, making it an attractive component of a 'lab-in-a-backpack' for resource-constrained environments in low-and-middle-income countries and synthetic biology in remote field stations. Leveraging the accessibility of 3D printing and off-the-shelf components, OpenCell can be manufactured and assembled at a low unit cost of less than $50, providing an affordable alternative to expensive laboratory equipment costing over $4000. OpenCell aims to overcome the barriers to entry in synthetic biology research and contribute to the growing collection of frugal and open hardware.

VIDEO SURVEILLANCE ON THE DRILLING RIG

The article describes a mobile video surveillance system on a drilling rig, which is designed to carry out technological control in high-risk areas at oil and gas producing enterprises. The advantages of this complex, circuit design solutions and functional properties of the device are presented. The field kit is installed directly at the facility in the hazardous area that needs to be monitored. The Polar Eye video surveillance system is designed to meet a number of industrial safety requirements at oil and gas production facilities. Video information from the danger zone is transmitted using the BSPD system, operating in the unlicensed 2.4 GHz frequency range, to the safe zone, where the analytical center for visual and operational control is located.The most important competitive advantages of the complex – low weight, compactness and mobility – were achieved by developing their own layout and circuit design solutions and by implementing most of the nodes on printed circuit boards of their own production.

Centralized Protection and Control for Transmission System Operations: Practical Applications and Perspectives

Centralized Protection and Control for Transmission System Operations: Practical Applications and Perspectives

Fast Stator Flux Trajectory Control for PMSM Operating Under Low Switching Frequency

In rail transit traction field, the traction motor needs to operate at a very low switching frequency to decrease the switching loss. Hybrid pulse-width modulation scheme is usually applied for decreasing switching frequency and providing good harmonic performance. However, when the transition between different modulation schemes occurs or the voltage command steps, the stator flux would deviate from the expected trajectory, which would lead to current/torque shock even overcurrent. This paper proposes a method which can provide more flexible choice of voltage vector and can fast eliminate the stator flux deviation. Compared with the previous method, the proposed one can provide better dynamic performance (less oscillation in current/torque and less settling time), especially when the pulse number is relatively low, like square-wave mode, and is easy to implement. The effectiveness of the proposed method is verified by the simulation and experimental results.

A multivariable control strategy based on fuzzy logic interference rule for a solar-driven, direct air-cooled H[formula omitted]O-LiBr absorption chiller

The operation of a solar-driven H2O-LiBr Absorption Chiller (AbC) is subjected to various limitations regarding its ability to satisfy efficiently the required cooling demand while avoiding certain internal conditions, such as H2O-LiBr solution crystallization and water freezing. These circumstances would lead to problematic situations and jeopardize the continuous operation of the system. Thus, the development of accurate control strategies is an issue of interest. A new operational control strategy approach is introduced and tested through simulation studies, by employing a transient model of the entire solar cooling application. A prototype under development is used for the parametrization of the direct air-cooled AbC model used in the simulations. The developed control strategy aims to minimize the electrical consumption of the auxiliary components of the AbC (i.e., fan, pumps) during the partial load operation period, by using a fuzzy logic interference rule for determining the cooling capacity demand and then applying an optimization algorithm for determining the velocity of the auxiliary components. Within the proposed control strategy, a fast-calculation model is embedded, which predicts the chiller’s capacity under variable external conditions and partial load operation. The electrical COP is increased up to 2.2 times with respect to a baseline case, based on a basic two-step control strategy, while allowing the chiller to operate smoother, minimizing the crystallization and freezing risk.

Behavioral Aspects of Operational Cost Control to Increase Profits in "X"

In running a business owned by an individual, it can be said to be successful if after a certain period of time the business experiences an increase in capital, profits or management in controlling costs. This research aims to find out whether controlling operational costs can increase profits at Tegoeh Djaja Konveksi Screen Printing. This research is a type of qualitative descriptive research, primary data obtained through interviews and literature review. The research method used in this research is a qualitative method, namely describing or describing the research results according to the conditions that occurred at the Tegoeh Djaja Konveksi Screen Printing. The research results obtained show that controlling operational costs cannot efficiently increase profits at Tegoeh Djaja Konveksi Screen Printing.

Design and Development of Agri-bot for Autonomous Seed Sowing and Harvesting

Abstract: This research delves into the development of an Autonomous Agriculture Robot (AAR) capable of performing seed sowing and harvesting operations. The AAR operates in two distinct modes: seed sowing and harvesting, leveraging advanced sensors and a control system to automate these critical agricultural processes. The AAR is engineered with dual operational modes, facilitated by an encoder system for precise autonomous navigation, servo actuation for operational control, and a Battery Management System (BMS) for efficient power usage. This paper details the design and development of a hardware prototype that presents the integration of these technologies. Validation results demonstrate the AAR’s capability to autonomously navigate and perform the defined tasks. The implementation of the AAR prototype signifies a pivotal step towards automating manual agricultural processes, potentially transforming the agricultural landscape by reducing labour requirements and increasing efficiency.

The Impact of Work Motivation and Work Discipline on Employee Performance Moderated by Transformational Leadership

This study delves into the intricate dynamics between work motivation, work discipline, employee performance, and transformational leadership within the realm of organizational effectiveness. Through a comprehensive review of existing literature, the research explores the influence of these factors on individual and organizational outcomes. Work motivation is examined as a pivotal driver of sustained performance, while work discipline is recognized for its role in promoting adherence to organizational norms and standards. Employee performance is scrutinized across various dimensions, encompassing task performance, adaptive performance, and contextual performance. Transformational leadership emerges as a critical leadership approach, characterized by its ability to boost morale, cultivate positive relationships, and inspire subordinates towards achieving organizational objectives. A sample of 118 employees from the Southern Border Food Processing CO, LTD operation control center participated in the study, providing data through a self-administered survey questionnaire. Analysis conducted using Smart (PLS) version 4.0 unveils significant impacts of work motivation, work discipline, and transformational leadership on employee performance, both individually and collectively. The majority of respondents in the study possess Senior High School and Diploma education, with varying levels of work experience.

The Effect of Technological Progress on Yarder Productivity: An Example from the Bulgarian Mountains

In recent years, a significant import of modern tower yarders has been registered in Bulgaria, where official productivity standards are routinely used for operational planning and control. Given the higher potential of the newer yarder models, the Bulgarian forestry sector has started a review of the older productivity standards dating back to the 1970s. This new endeavor has offered an ideal opportunity for gauging the effect of technological progress in yarder technology. Therefore, the authors have used the very first results achieved during the development of the new standards for conducting a preliminary quantitative comparison between older and newer yarder types. Modern yarders (e.g., Konrad Mounty 4000) are much faster than the older ones (e.g., Koller K300), and their time consumption per cubic meter is half as large, especially on longer distances. At short distances, however, their performance evens out. Regardless of the distance, the installation time of the Konrad Mounty 4000 is twice as short. As they are largely automated, the new machines can be manned by smaller crews (e.g., two workers instead of three) and are easier and safer to operate. Finally, the new machines are equipped with built-in loaders and processors, which allows them to integrate delimbing, crosscutting and stacking within the same work cycle. With older models, a separate team must be deployed for those tasks.

Bidirectional DC - DC Converter Topology for Electric Vehicles Using Fuzzy Logic Controller

This project organizes an application of hybrid electric vehicle systems operated with novel designed bidirectional dc-dc converter (BDC) which interfaces a main energy storage (ES1), an auxiliary energy storage (ES2) and dc bus of different voltage levels. Proposed BDC converter can operate both step up and step-down mode. In which step up mode represents low voltage dual source -powering mode and step-down mode represents high voltage dc link energy –regenerating mode, both the modes are operated under the control of bidirectional power flow. This model can independently control power flow between low voltage dual source buck/boost modes. Here in, the circuit configuration, operation, steady-state analysis, and closed-loop control of the proposed BDC are discussed according to its three modes of power transfer. In this project fuzzy logic controller is used and also system results are validating through MATLAB/SIMULINK software. Index Terms—Bidirectional dc/dc converter (BDC), dual battery storage, hybrid electric vehicle, Fuzzy logic controller.

Ammonia fueled engine with diesel pilot ignition: Approach to achieve ultra-high ammonia substitution

Ammonia is a hydrogen-rich zero-carbon fuel, and is one of the most promising approaches to realize energy decarbonization in the fields of industry and transportation. Efficient operation and emissions control have been the primary obstacle to develop engines with high ammonia energy share. In this study, the combustion and emissions of an ammonia-fueled engine with diesel pilot ignition are investigated, and the target is to achieve ultra-high ammonia substitution with acceptable thermal efficiency. The ammonia energy share is first increased from 30% to 90% at an intermediate load, with a split diesel injection triggering ammonia combustion. It found that the increased ammonia energy share reduces the indicated thermal efficiency from 48.3% to 38.9% with high unburned ammonia emissions. The NOx emissions exhibit a turning point with increased ammonia substitution, which indicates that the NOx emissions transition from the thermal-dominated to the fuel-dominated regime. The diesel pilot injection strategy is then optimized, by advancing the main injection timing and changing the pre-injection amount and the interval between two injection events. Optimized diesel injection controls the ignition timing and combustion process, thereby improving thermal efficiency and emissions at high ammonia energy shares. An ultra-high ammonia energy share of 95% could be finally achieved, and the thermal efficiency is 40.2%. It is also noted that as engine load increases, engine thermal efficiency at an ammonia energy share of 80% could be elevated to 44.2%.

A Compact Aerial Manipulator: Design and Control for Dexterous Operations

The lack of aerial physical interaction capability is one of the choke points limiting the extension of aerial robot applications, such as rescue missions and aerial maintenance. We present a new aerial robotic manipulator (AEROM) for aerial dexterous operations in this work. It contains a robotic manipulator with 6-degree-of-freedom and a compact flight platform. Firstly, we propose a quantitative capability index to evaluate and guide the mechanical design of the AEROM. Based on the proposed quantitative index, we construct a lightweight bird-inspired manipulator to imitate a raptor hindlimb. An additional telescopic joint and an end-effector consisting of three soft fingers allow the AEROM to execute aerial interaction tasks. In addition, the wrist joints enable independent control of the end-effector attitude regardless of the flight platform. After explicitly analyzing the multi-source disturbances during the aerial operation tasks, we develop a refined anti-disturbance controller to compensate for the disturbances with different characteristics. The proposed controller further improves the position accuracy of end-effector to enable dexterous operations during aerial interaction tasks. Finally, the physical experiments verify the effectiveness of the proposed AEROM system.

Managing Inherent IT Business Risk against Cyber Threats: a Decision Analysis Case Study of an Oil and Gas Company

XYZ, an anonymized oil and gas company, aims to enhance cyber resilience by strategically managing inherent risk profiles in cybersecurity, aligned with business needs and stakeholder expectations. This research addresses challenges including Information Security Control determination, proficiency improvement in risk management, and ISMS preparedness. Additionally, it tackles procurement strategy for Security Operations Control across XYZ Group, operating under PSC Gross Split, Cost Recovery, and Non-PSC statuses. Utilizing diverse frameworks such as problem tree analysis, stakeholders’ power-interest matrix, MITRE ATT&CK, NIST 800-53, COBIT 2019, ISO 27005:2022, KAMI 5.0, and SMART, data analysis includes risk documents, interviews, and cyber-attack data. The research establishes effective IS Control for risk mitigation, readiness for Information Security Management System ISMS implementation, strategic programs enhancing risk management capability, and refined Security Operations Control procurement. These outcomes, incorporated into a collaborative contract structure, significantly mitigate cyber threats and potential impacts, such as disruptions to operations, revenue reduction, increased costs, data theft, and non-compliance.

Reporting Control Deficiencies in Repeat Internal Audit Engagements*

ABSTRACTThis study examines the reporting of control deficiencies in repeat internal audit engagements. Experienced internal auditors were presented with a hypothetical case in which they were asked about the likelihood of reporting an internal control deficiency discovered last year but which was, “through an oversight,” not reported to company management. The study varies whether the deficiency is an operational control or an internal control over financial reporting and who identified but failed to report the deficiency last year (either the participant, the participant's colleague whom they like and admire, or a colleague whom they neither like nor dislike). The results show that internal auditors are less likely to report an operational deficiency (versus a financial reporting deficiency) in the current year that was not reported last year. Further, internal auditors are less likely to report a control deficiency in the current year when they themselves or a colleague they like and admire (versus a colleague they feel neutral about) failed to report it last year.

Combined Observer-Based State Feedback and Optimized P/PI Control for a Robust Operation of Quadrotors

This paper deals with a discrete-time observer-based state feedback control design by taking into consideration bounded parameter uncertainty, actuator faults, and stochastic noise in an inner control loop which is extended in a cascaded manner by outer PI- and P-control loops for velocity and position regulation. The aim of the corresponding subdivision of the quadrotor model is the treatment of the control design in a systematic manner. In the inner loop, linear matrix inequality techniques are employed for the placement of poles into a desired area within the complex z-plane. A robustification of the design towards noise is achieved by optimizing both control and observer gains simultaneously guaranteeing stability in a predefined bounded state domain. This procedure helps to reduce the sensitivity of the inner control loop towards changes induced by the outer one. Finally, a model-based optimization process is employed to tune the parameters of the outer P/PI controllers. To allow for the validation of accurate trajectory tracking, a comparison of the novel approach with the use of a standard extended Kalman filter-based linear-quadratic regulator synthesis is presented to demonstrate the superiority of the new design.