Nonmonotonic reasoning from conditional knowledge bases with system W

For nonmonotonic reasoning in the context of a knowledge base $\mathcal {R}$ R containing conditionals of the form If A then usually B, system P provides generally accepted axioms. Inference solely based on system P, however, is inherently skeptical because it coincides with reasoning that takes all ranking models of $\mathcal {R}$ R into account. System Z uses only the unique minimal ranking model of $\mathcal {R}$ R , and c-inference, realized via a complex constraint satisfaction problem, takes all c-representations of $\mathcal {R}$ R into account. C-representations constitute the subset of all ranking models of $\mathcal {R}$ R that are obtained by assigning non-negative integer impacts to each conditional in $\mathcal {R}$ R and summing up, for every world, the impacts of all conditionals falsified by that world. While system Z and c-inference license in general different sets of desirable entailments, the first major objective of this article is to present system W. System W fully captures and strictly extends both system Z and c-inference. Moreover, system W can be represented by a single strict partial order on the worlds over the signature of $\mathcal {R}$ R . We show that system W exhibits further inference properties worthwhile for nonmonotonic reasoning, like satisfying the axioms of system P, respecting conditional indifference, and avoiding the drowning problem. The other main goal of this article is to provide results on our investigations, underlying the development of system W, of upper and lower bounds that can be used to restrict the set of c-representations that have to be taken into account for realizing c-inference. We show that the upper bound of n − 1 is sufficient for capturing c-inference with respect to $\mathcal {R}$ R having n conditionals if there is at least one world verifying all conditionals in $\mathcal {R}$ R . In contrast to the previous conjecture that the number of conditionals in $\mathcal {R}$ R is always sufficient, we prove that there are knowledge bases requiring an upper bound of 2n− 1, implying that there is no polynomial upper bound of the impacts assigned to the conditionals in $\mathcal {R}$ R for fully capturing c-inference.

Development of an Information System for the Distance Learning Process Organization

The article describes the process of creating a personal account system for correspondence students, starting with the study of the issue as a whole and ending with the process of developing one of the main components of the information system. The process of creating an IS includes such stages as: determining the required functionality, designing the overall architecture of the system and each of its components. The technologies and software solutions used to system implementation are described, as well as the method of integrating the created solution with the existing information infrastructure of the educational institution. A brief mathematical description of one of the tasks solved by the information system, automated schedule generation, is also given.

Manajemen Kas Berbasis Virtual Account Pada PT PLN (Persero) UPP Pembangkit Jawa Bagian Barat

The company's operational activities can run optimally if cash is managed properly. In the cash of PT PLN (Persero) UPP Pembangkit Jawa Barat there is petty cash which is used to finance the company's operational activities of small value. The purpose of this study was to determine petty cash management based on the virtual account system at PT PLN (Persero) Unit Pelaksana Proyek (UPP) Pembangkit Jawa Bagian Barat so that it could see the cash management process more effectively and efficiently. This research is descriptive in nature, namely research by describing the condition of the company based on actual conditions. From the results of this study, it was found that PT PLN (Persero) Unit Pelaksana Proyek (UPP) Pembangkit Jawa Bagian Barat uses a cash management system with the Imprest system by determining the petty cash value that has been determined per week by PT PLN (Persero) Unit Induk Pembangunan (UIP) Jawa Bagian Barat. Petty cash is taken using an ATM card media which can only be withdrawn for petty cash during working hours and days. Cash management through virtual accounts really helps the cash management process in real time and minimizes idle cash.

Nonlinear state feedback controller combined with RBF for nonlinear underactuated overhead crane system

This paper proposes a robust control scheme for an underactuated crane system. The presented scheme contains two control strategies, feedback control term and corrective control term, based on Radial Basis Function (RBF) neural networks. A feedback control term is deigned based on the nominal dynamic model of the controlled system. RBF neural networks have been used as adaptive control term to compensate for the system uncertainties and external disturbance. Lyapunov stability theorem has been used to derive updating laws for the weights of the RBF neural networks. To illustrate the robustness and effectiveness of the proposed controller, Matlab program is used to simulate the model of the nonlinear overhead crane system with the proposed control method, taking into account system uncertainties and external disturbance. Simulation results indicated superior control performance of the proposed control method compared to the other control methods used in the test.

From centralized DRG costing to decentralized TDABC-assessing the feasibility of hospital cost accounting for decision-making in Denmark

Background The objective is to examine hospital cost accounts to understand the foundation upon which healthcare decisions are based. More specifically, the aim is to add insights to accounting practices and their applicability towards a newly establish value-based agenda with a focus on patient-level cost data. Methods We apply a cost accounting framework developed to position and understand hospital cost practices in relation to government requirements. Allocated cost account data from 2015 from all Danish hospitals were collected and analyzed. These cost accounts lay the foundation for diagnosis related group (DRG) rate setting. We further compare the data’s limitations and potential in a value-based healthcare (VBHC) agenda with the aim of implementing time-driven activity based costing (TDABC). Results We find exceedingly aggregated department-level data that are not tied to patient information. We investigate these data and find large data skewness in the current system, mainly due to structural variances within hospitals. We further demonstrate the current costs data’s lack of suitability for VBHC but with suggestions of how cost data can become applicable for such an approach, which will increase cost data transparency and, thus, provide a better foundation for both local and national decision-making. Conclusions The findings raise concerns about the cost accounts’ ability to provide valid information in healthcare decision-making due to a lack of transparency and obvious variances that distort budgets and production-value estimates. The standardization of costs stemming from hospitals with large organizational differences has significant implications on the fairness of resource allocation and decision-making at large. Thus, for hospitals to become more cost efficient, a substantially more detailed clinically bottom-led cost account system is essential to provide better information for prioritization in health.

Manufacturing Capacity Management By Using Modern Simulation Tools

Determining the parameters of the production system as well as the choice of the type of manufactured elements flow shall appoint the level of effectiveness of the manufacturing process. The article presents an example of implementation the simulation verification process of the production flow, taking into account system constraints. The basic stages of developing a simulation model in this process are discussed, taking into account the necessary information and input data. The results show the impact of the application selected flow scenarios on the level of generated costs and the duration of the manufacturing process. The process of assessing individual variants of the organization production was performed on the basis of the results obtained by computer simulation in the FlexSim simulation software.

Dynamic visual servoing with Kalman filter-based depth and velocity estimator

Camera calibration error, vision latency, nonlinear dynamics, and so on present a major challenge for designing the control scheme for a visual servoing system. Although many approaches on visual servoing have been proposed, surprisingly, only a few of them have taken into account system dynamics in the control design of a visual servoing system. In addition, the depth information of feature points is essential in the image-based visual servoing architecture. As a result, to cope with the aforementioned problems, this article proposes a Kalman filter-based depth and velocity estimator and a modified image-based dynamic visual servoing architecture that takes into consideration the system dynamics in its control design. In particular, the Kalman filter is exploited to deal with the problems caused by vision latency and image noise so as to facilitate the estimation of the joint velocity of the robot using image information only. Moreover, in the modified image-based dynamic visual servoing architecture, the computed torque control scheme is used to compensate for system dynamics and the Kalman filter is used to provide accurate depth information of the feature points. Results of visual servoing experiments conducted on a two-degree of freedom planar robot verify the effectiveness of the proposed approach.

Interactive Tree Of Life (iTOL) v5: an online tool for phylogenetic tree display and annotation

The Interactive Tree Of Life (https://itol.embl.de) is an online tool for the display, manipulation and annotation of phylogenetic and other trees. It is freely available and open to everyone. iTOL version 5 introduces a completely new tree display engine, together with numerous new features. For example, a new dataset type has been added (MEME motifs), while annotation options have been expanded for several existing ones. Node metadata display options have been extended and now also support non-numerical categorical values, as well as multiple values per node. Direct manual annotation is now available, providing a set of basic drawing and labeling tools, allowing users to draw shapes, labels and other features by hand directly onto the trees. Support for tree and dataset scales has been extended, providing fine control over line and label styles. Unrooted tree displays can now use the equal-daylight algorithm, proving a much greater display clarity. The user account system has been streamlined and expanded with new navigation options and currently handles >1 million trees from >70 000 individual users.

El dinero como medio de cambio y su evolución: análisis de Katsuhito Iwai y su interpretación de Carl Menger

This paper presents an analysis of the acceptability and evolution of money in Iwai’s monetary proposal. He develops an interesting «search theoretical model» of money as medium that is accepted in exchange in a decentralized economy, the origin of which finds in Carl Menger idea, according to this function of money it emerges spontaneously. Iwai argues that money is used as universal medium of exchange simply because every-body uses it as money: «bootstrap mechanism». Such mechanism allows the economy to have as much monetary equilibrium as the number of durable goods in it. However, Iwai says that money never evolved naturally, becau-se there must have been a large symmetry –breaking disturbance to crea-te it in the beginning, and then, there is a fundamental limit on the power of the theory to explain the origin of money. History thus matters essentially. The purpose of this paper is to put these statements to a critical test. First of all, the bootstrap mechanism does not impair Menger’s monetary theory, contrary to what Iwai may think. It confirms Menger’s statements regarding to the practice and custom as relevant to the origin of money. Another outcome of this study shows that Iwai’s proposal may complete the Arrow-Debreu theory of value in the framework of exchange, because it elimina-tes the hypothesis of a centralized account system. Finally, a third relevant outcome of this work is a critic to Iwai theory, because it shows, against him, that monetary equilibrium depends of «real economic» foundations (tech-nique and preferences), to support itself as a Nash equilibrium. Key words: Origin of money, money as medium of exchange, monetary equilibrium. Códigos JEL: B16, E0, E42, P16. Resumen: Este ensayo presenta un análisis de la aceptabilidad y evolución del dinero en la propuesta que hace Iwai al respecto. Él desarrolla un inte-resante «modelo teórico de búsqueda» del dinero como medio de cambio aceptado en las transacciones de una economía descentralizada, cuyo origen se encuentra en la idea de Carl Menger, de acuerdo con la cual esta función de la moneda emerge espontáneamente. Iwai arguye que el dine-ro es usado como medio de cambio universal simplemente porque todos lo usan como dinero: «el mecanismo de auto sostenimiento». Tal mecanis-mo permite que la economía tenga tantos equilibrios como bienes dura-deros. Sin embargo, Iwai dice que el dinero nunca evolucionó natural-mente, porque debió haber habido una gran simetría –que alterara lo creado en el inicio, y entonces, existe un límite fundamental en el poder de la teoría para explicar el origen del dinero. Así la historia es un asun-to esencial. El propósito de este ensayo es someter estos argumentos a un análisis crítico. En primer lugar, al contrario de lo que Iwai piensa, el meca-nismo de auto sostenimiento no deteriora la teoría monetaria de Menger. Éste confirma los argumentos de Menger relacionados con la relevancia de la práctica y la costumbre en el origen del dinero. Otro resultado de este estudio muestra que la propuesta de Iwai puede completar la teoría del valor de Arrow-Debreu en el marco del intercambio, porque elimina la hipótesis de un sistema de cuentas centralizado. Finalmente, un tercer resultado relevante de este trabajo es una crítica a la teoría de Iwai, porque este muestra, en contra de él, que el equilibrio monetario depende de los «fundamentales de la economía» (técnica y preferencias), para auto soste-nerse como un equilibrio de Nash. Palabras clave: Origen del dinero, dinero como medio de cambio, equili-brio monetario.

Challenges and Opportunities in the Application of China’s Central Bank Digital Currency to the Payment and Settle Account System

<p>With the advancement of the Internet and big data technology, currency has gradually developed in the direction of virtualization and digitization. The governments and central banks of various countries have gradually begun to pay attention to the role of digital currencies, and central bank digital currencies have emerged as the times require. As one of the first countries to study digital currency, China will devote itself to applying central bank digital currency to actual transactions in the future.</p><div>This article focuses on how China’s CBDC is used in the transaction settlement system. The opportunity is that the central bank’s digital currency technology improves the security, flexible operation and diversified application scenarios of the overall transaction settlement system, and further safeguards China’s national financial sovereignty. The challenge is that the current technology is still uncertain and different from the traditional RMB. In the future, China’s CBDC will also compete fiercely with other sovereign currencies. It is recommended to strengthen technological innovation, improve the relevant systems and regulations of the central bank’s digital currency operation, and make relevant policies to prevent the United States from imposing political and economic sanctions on China. This article will provide</div><div>suggestions on the challenges that the People’s Bank of China may face in the future application of digital currency to the transaction settlement system.</div>