Attention: A view suggested by systemic and cybernetic consideration

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Current views and models about attention regard man as a 'transmitter channel' and try to characterise the properties of that 'odd channel'. Another characteristic of the current views is that attention is regarded as a specific mental operation in a person which can be described, irrespective of the purposes of the subject. By contrast we examine attention as an activity at the service of the purposes of the person. Attention is examined as an activity by means of which the field of consciousness is structured around the 'object of attention'. This object of attention is not a specific 'stimulus' but a system in the sense of General System Theory. Hence, the approach is mainly holistic in character. Activity is looked upon as an INTERTRAFFIC between the person and his relation with the world. And where there is relatedness, information theory, in a cybernetic sense, can be used. The approach developed benefits of the advantages from previous models allowing also for a better explanation of the limitation present in the cognitive realm without appeal to some 'filter mechanism' in the physiological structure of a person.Consejo de Desarrollo Cientifico y Humanistico U. C. V. Caraca

Effect of Metallic Waste Addition on the Physical and Mechanical Properties of Cement-Based Mortars

© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).This paper investigates the influence of the type and amount of recycled metallic waste on the physical and mechanical properties of cement-based mortars. The physical and mechanical properties of cement mortars, containing four different amounts of metallic waste (ranged 4 to 16% by cement weight), were evaluated by measuring the bulk density, total porosity, flexural and compressive resistance, and dynamic elastic modulus by ultrasonic tests. All the properties were measured on test specimens under two curing ages: 7 and 28 days. Additionally, the morphological properties and elemental composition of the cement and metallic waste were evaluated by using Scanning Electron Microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS), and X-ray fluorescence (XRF). Main results showed that the addition of metallic waste reduced the bulk density and increased the porosity of the cement-based mortars. Furthermore, it was observed that flexural and compressive strength proportionally increased with the metallic waste addition. Likewise, it was proven that elastic modulus, obtained by compressive and ultrasonic tests, increases with the metallic waste amount. Finally, based on a probability analysis, it was confirmed that the addition of metallic waste did not present a significant effect on the mechanical performance of the cement-based mortars.Peer reviewedFinal Published versio

Fracture in Phenolic Impregnated Carbon Ablator

The thermal protection materials used for spacecraft heat shields are subjected to various thermal-mechanical loads during an atmospheric entry which can threaten the structural integrity of the system. This paper discusses the development of a novel technique to understand the failure mechanisms inside thermal protection materials. The focus of research is Phenolic Impregnated Carbon Ablator (PICA). It has successfully flown on the Stardust spacecraft and is the TPS material chosen for the Mars Science Laboratory (MSL) and Dragon spacecraft. Although PICA has good thermal properties, structurally, it is a weak material. In order to thoroughly understand failure in PICA, fracture tests were performed on FiberForm* (precursor of PICA), virgin and charred PICA materials. Several samples of these materials were tested to investigate failure mechanisms at a microstructural scale. Stress-strain data were obtained simultaneously to estimate the fracture toughness. It was found that cracks initiated and grew in the FiberForm when a critical stress limit was reached such that the carbon fibers separated from the binder. However, both for virgin and charred PICA, crack initiation and growth occurred in the matrix (phenolic) phase. Both virgin and charred PICA showed greater strength values compared to FiberForm coupons, confirming that the presence of the porous matrix helps in absorbing the fracture energy

Predicting USMLE Step 2 Scores Using Results from the NBME Shelf Exams

Background In February of 2020 the sponsors of the USMLE examinations, which includes the NBME and the Federation of State Medical Boards (FSMB) decided to change the scoring system of the USMLE Step 1 from a three-digit numeric score to a Pass/Fail outcome1. The basis of this change was made to “address concerns about Step 1 scores impacting student well-being and medical education”2. Historically, the three-digit numeric score from Step 1 has been one of the top determining factors for admission into residency3. This change will cause a shift in the priority of objective and subjective factors about applicants that residency program directors use to assess medical students. The purpose of this study is to further assess the correlation between core clerkship NBME Shelf exam scores with performance on the USMLE Step 2. Predicting performance on the USMLE Step 2 is of more importance now that the Step 1 scoring system was changed to a Pass/Fail outcome. We expect that the scores on the NBME shelf exams will be correlated to the overall performance on USMLE Step 2, further supporting the conclusions of the previous study by Zahn et al4. Methods Data containing students’ performance on the USMLE Step 2 and NBME Shelf exams was obtained from Blackboard and One45. In order to protect student confidentiality, data will be de-identified at the point of collection by supervising faculty. From the clerkship assessment score (professionalism, clinical knowledge, shelf exam, etc.) each component will be standardized and converted into a z-score. The NBME Shelf Exams and USMLE Step 2 score will also be converted into a standardized z-score. Standardized USMLE Step 2 T-scores will be substituted in place of NBME Shelf T-scores and final grading computation will analyze the frequency of each grade type (Honors, High Pass, Pass, Fail). Linear regression will be used to determine the correlation between USLME Step 2 scores and performance on the Clerkship Shelf Exams. To assess the effect size of the regression equation, a squared correlation coefficient (R2) will be computed between scores of the USLME Step 2 and NBME Shelf Exams. Results Data collection complete after update to IRB research proposal was approved. Data analysis underway with preliminary results expected in early Spring 2021. Conclusion Further analysis of the data is required for proper conclusions to be drawn

Managing Food Quality Risk in Global Supply Chain: A Risk Management Framework

Today, the food sector is one of the sectors most vulnerable to intentional contamination by debilitating agents [1]. Some cases of contaminated food have indicated that product quality risk is one of the vulnerabilities in the global supply chain. A series of company scandals, affecting reputation and causing the recall of products and increasing costs have hit the food industry. The obvious problem is that even a minor incident in one part of the chain can have disastrous effects on other parts of the supply chain. Thus, risks are transmitted through the chain. Even though the dangers from members in the supply chain are small, the cumulative effect becomes significant. The aim of this study is to propose an integrated supply chain risk management framework for practitioners that can provide directions for how to evaluate food quality risk in the global supply chain. For validating the proposed model in‐depth, a case study is conducted on a food SME distributor in Central America. The case study investigates how product quality risks are handled according to the proposed framework

Desarrollo del cronograma y costo del saneamiento en la zona rural con biodigestores en diez localidades de la provincia de San Miguel - Cajamarca

El desarrollo de esta tesis está enfocada principalmente en la elaboración de una propuesta de planeación de la Gestión del cronograma y costos con el uso del PMBOK sexta edición, para la construcción de una obra de saneamiento básico con biodigestores, proyecto de saneamiento localizado en la provincia de San Miguel del departamento de Cajamarca. El proyecto consiste en la construcción de 831 unidades básico de saneamiento (letrina con arrastre hidráulico con biodigestor para el tratamiento de excretas). En la parte primera se basa en describir el problema real, donde podemos precisar que no contamos con herramientas que ayuden a llevar un control de la ejecución del Proyecto desde el inicio hasta el final. Se justifica pues mediante este estudio se va a desarrollar un plan de gestión tomando como base los conocimientos PMBOK, basados principalmente en dos conocimientos (cronograma y costo), se buscará hacer comparaciones con el método del valor ganado, realización de un cronograma mediante el Microsoft Project, esta propuesta servirá para obras similares, para que así puedan tener un mejor control en la dirección de proyectos basado en el cronograma y costos. Se tiene el Objetivo principal y secundarios que se basa principalmente en desarrollar un plan de gestión del cronograma y costos en la ejecución de la obra de saneamiento con biodigestores de la zona rural de la Provincia de San Miguel. El marco teórico está desarrollado a través de los conocimientos del PMBOK. Por último, la metodología a usar será mediante el levantamiento de información en las 10 localidades donde se ejecutó la obra y análisis documental Bibliográfico sobre Project Management Institute (PMBOK). Finalmente, el proyecto nos conduce a una optimización del trabajo, sin afectar la rentabilidad del proyecto el tiempo de ejecución la obra, cumpliendo con los requisitos de buena Gestión de Proyectos.The development of this thesis is mainly focused on the elaboration of a planning proposal for the management of the schedule and costs with the use of the sixth edition PMBOK, for the construction of a basic sanitation work with biodigesters, a sanitation project located in the province from San Miguel of the department of Cajamarca. The project involves the construction of 831 basic sanitation units (latrine with hydraulic drag with biodigester for excreta treatment). In the first part it is based on describing the real problem, where we can specify that we do not have tools that help to keep track of the execution of the Project from the beginning to the end. It is justified because through this study a management plan will be developed based on PMBOK knowledge, based mainly on two knowledge (schedule and cost), it will seek to make comparisons with the method of earned value, making a schedule through Microsoft Project, this proposal will serve for similar works, so that they can have better control in the direction of projects based on the schedule and costs. The main and secondary Objective is based, which is mainly based on developing a schedule of management of the schedule and costs in the execution of the sanitation work with biodigesters in the rural area of the Province of San Miguel. The theoretical framework is developed through the knowledge of PMBOK. Finally, the methodology to be used will be through the collection of information in the 10 locations where the work was carried out and Bibliographic documentary analysis on Project Management Institute (PMBOK). Finally, the project leads us to an optimization of the work, without affecting the profitability of the project the execution time of the work, complying with the requirements of good Project Management.Tesi

Espacio público en la seguridad ciudadana, caso de estudio: Plaza de Armas, Piura-Perú, 2023

El espacio público ha sido objeto de mediaciones que intentan transformarlo en el centro de conjunción, para arreglar el daño a la textura social visto en entornos metropolitanos inequívocos. Esto ha propiciado que, en gran medida impulsados por encuentros efectivos en diferentes regiones del planeta, plazas, paseos, bajo andamios y paradas hayan sido renovados, preparados y moldeados para convertirse en lugares de refugio para la concurrencia. Así las cosas, el presente estudio se orienta a conocer el espacio público en la seguridad ciudadana Piura- Perú. Así las cosas, el procedimiento organizado de la revisión es de metodología subjetiva y el plan seccional de no-ensayo a través de un examen aplicado en vista de la racionalidad del enfoque de exploración subjetiva. Este estudio casual es tanto de prueba como de medición, En este párrafo se discuten las diferentes interpretaciones y debate en torno a los conceptos de causalidad y explicaciones causales. La posición del paradigma positivista considera que la causalidad es experimental y que obedece a regularidades probabilísticas

Activities for Mech E\u27s

This document will describe the development of a solution for enforcing the topics covered in the ME 329 - Mechanical System Design curriculum by bringing quality equipment to a classroom setting. The project Sponsor, Professor Lauren Cooper, has also noticed a lack of hands-on experience for many students entering this class. Our team is attempting to develop a solution for this problem. To better understand what students would want to learn, or would have liked to learn more about, we conducted surveys of past, present, and future students as well as conducted interviews with professors that have taught the course. We also researched past projects from different schools as well as articles of similar products that are and were on the market. All of this information led to the conclusion that students will most benefit from (and enjoy) a lab project where they first learn fundamental gear train concepts with an exploratory approach, then work on a project that combines the theoretical concepts learned in the course with the experimental results obtained from a physical apparatus. Through ideation, concept prototyping, functional decomposition, and morphological decision-making, we came up with a two-part solution. The solution will be a pair of activities that students will complete over a multi-week period. The first activity will be a modular, hands-on apparatus that students can configure with different parameters to see how these changes affect the system\u27s performance. In the second, students will apply their knowledge from the exploratory lab into a design activity that models a real-world scenario, in this case a wind turbine. To prototype the activities, we purchased a number of components, screws, and measuring devices. Many of the components came from a single online supplier, ServoCity. These components were picked for their configuration capability, being able to be arranged into many configurations. The rest of the components require only a small amount of modification or are 3D printed. Both designs were tested against technical engineering specifications, as well as at least some amount of user testing from current or former students and faculty. Both designs met the specifications, and we are confident they will serve well as solutions to the problem posed. In addition to creating prototypes, we also developed lesson plans and lab manuals for both activities. The former provides suggestions to professors for how to implement the activity including optimal group sizes, time to spend on each activity, and work to require of students. The latter prepares students to interact with the activities and walks them through guided activities to facilitate discovery of important concepts. The following report describes the background, objectives, design process, prototyping process, and verification process for this project as well as the recommendations and next steps for our Sponsor after receiving the results