scholarly journals Design of Sustainable Renewable-Based Utility Plants in the Face of Uncertainty

2021 ◽  
Vol 2 ◽  
Author(s):  
Salvador I. Pérez-Uresti ◽  
Mariano Martín ◽  
Arturo Jiménez-Gutiérrez
Keyword(s):  
Renewable Resources ◽  
Uncertain Parameter ◽  
Mixed Integer ◽  
Model Formulation ◽  
Biomass Waste ◽  
Design Flexibility ◽  
Investment Cost ◽  
The Face ◽  
Different Levels ◽  
Monthly Probability

This work presents the formulation of a two-stage stochastic mixed-integer linear programming (MILP) model to include uncertainty in the design of renewable-based utility plants. The model is based on a superstructure that integrates technologies to process biomass, waste, solar radiation, and wind and considers uncertainty in availability of the renewable resources and on the utility demands. The uncertain parameter space is calculated based on a monthly probability density function for each uncertain parameter and discretized into different levels. It is shown that as uncertainty is considered in the model formulation, design flexibility improves with respect to the deterministic-based designs, although the flexibility is achieved at the expense of higher underused facilities and therefore unused investment cost.

scholarly journals On monotonicity and search strategies in face-based copositivity detection algorithms

2021 ◽  
Author(s):  
B. G.-Tóth ◽  
E. M. T. Hendrix ◽  
L. G. Casado
Keyword(s):  
Research Question ◽  
Quadratic Function ◽  
Mixed Integer ◽  
Quadratic Program ◽  
Matrix Methods ◽  
Detection Algorithms ◽  
Standard Simplex ◽  
Mathematical Properties ◽  
The Face ◽  
Spatial Branch And Bound

AbstractOver the last decades, algorithms have been developed for checking copositivity of a matrix. Methods are based on several principles, such as spatial branch and bound, transformation to Mixed Integer Programming, implicit enumeration of KKT points or face-based search. Our research question focuses on exploiting the mathematical properties of the relative interior minima of the standard quadratic program (StQP) and monotonicity. We derive several theoretical properties related to convexity and monotonicity of the standard quadratic function over faces of the standard simplex. We illustrate with numerical instances up to 28 dimensions the use of monotonicity in face-based algorithms. The question is what traversal through the face graph of the standard simplex is more appropriate for which matrix instance; top down or bottom up approaches. This depends on the level of the face graph where the minimum of StQP can be found, which is related to the density of the so-called convexity graph.

scholarly journals The Hierarchy of Walking Needs and the COVID-19 Pandemic

2021 ◽  
Vol 18 (14) ◽  
pp. 7461
Author(s):  
Mohammad Paydar ◽  
Asal Kamani Fard
Keyword(s):  
Mental Health ◽  
Urban Design ◽  
Public Spaces ◽  
Empirical Literature ◽  
The World ◽  
The Face ◽  
Current Context ◽  
Mode Of Transport ◽  
Different Levels

More than 150 cities around the world have expanded emergency cycling and walking infrastructure to increase their resilience in the face of the COVID 19 pandemic. This tendency toward walking has led it to becoming the predominant daily mode of transport that also contributes to significant changes in the relationships between the hierarchy of walking needs and walking behaviour. These changes need to be addressed in order to increase the resilience of walking environments in the face of such a pandemic. This study was designed as a theoretical and empirical literature review seeking to improve the walking behaviour in relation to the hierarchy of walking needs within the current context of COVID-19. Accordingly, the interrelationship between the main aspects relating to walking-in the context of the pandemic- and the different levels in the hierarchy of walking needs were discussed. Results are presented in five sections of “density, crowding and stress during walking”, “sense of comfort/discomfort and stress in regard to crowded spaces during walking experiences”, “crowded spaces as insecure public spaces and the contribution of the type of urban configuration”, “role of motivational/restorative factors during walking trips to reduce the overload of stress and improve mental health”, and “urban design interventions on arrangement of visual sequences during walking”.

Dynamic resource allocation and coordination for high-load crisis volunteer management

2018 ◽  
Vol 8 (4) ◽  
pp. 533-556 ◽  
Author(s):  
Christopher Garcia ◽  
Ghaith Rabadi ◽  
Femida Handy
Keyword(s):  
Resource Allocation ◽  
Renewable Resources ◽  
High Load ◽  
Mixed Integer ◽  
Volunteer Management ◽  
Large Set ◽  
Content Type ◽  
Dynamic Resource ◽  
Crisis Scenarios ◽  
Commercial Solver

Purpose Every year volunteers play a crucial role in disaster responses around the world. Volunteer management is known to be more complex than managing a paid workforce, and this is only made worse by the uncertainty of rapidly changing conditions of crisis scenarios. The purpose of this paper is to address the critical problem of assigning tasks to volunteers and other renewable and non-renewable resources simultaneously, particularly under high-load conditions. These conditions are described by a significant mismatch between available volunteer resources and demands or by frequent changes in requirements. Design/methodology/approach Through a combination of literature reviews and interviews with managers from several major volunteer organizations, six key characteristics of crisis volunteer resource allocation problems are identified. These characteristics are then used to develop a general mixed integer programming framework for modeling these problems. Rather than relying on probabilistic resource or demand characterizations, this framework addresses the constantly changing conditions inherent to this class of problems through a dynamic resource reallocation-based approach that minimizes the undesirable impacts of changes while meeting the desired and changing objectives. The viability of this approach for solving problems of realistic size and scale is demonstrated through a large set of computational experiments. Findings Using a common commercial solver, optimal solutions to the allocation and reallocation problems were consistently obtained in short timespans for a wide variety of problems that have realistic sizes and characteristics. Originality/value The proposed approach has not been previously addressed in the literature and represents a computationally tractable method to allocate volunteer, renewable and non-renewable resources to tasks in highly volatile crisis scenarios without requiring probabilistic resource or demand characterizations.

scholarly journals E- HRM Practices in the IT Industry with Special Reference to the State of Karnataka

2019 ◽  
Vol 8 (3S3) ◽  
pp. 249-253
Keyword(s):  
Performance Management ◽  
Human Resource ◽  
Training And Development ◽  
It Industry ◽  
Performance Management Systems ◽  
The Face ◽  
Self Service ◽  
Employee Self Service ◽  
Different Levels

Human resource management is constantly evolving into a technology-based service provider to their employees. In today’s organizations, employees see the face of HR as an Intranet portal rather than a human on the other side. This transformation of Human Resource services through technology is now being coined as E-HRM or electronic human resource. The Use of E-HRM in today’s Organizations, are in many function areas such as training and development, performance management systems, hiring and employee self-service. Organisations who adopt HR technology tools outperform those that do not. Interestingly early on the HR department was the last recipient of IT benefits in any organization, it started from keeping the database of the employees. In the present scenario employees are considered as the strategic partners of the organization and the use of high-end software have changed the face of HR departments and a new term has been coined as E-HRM. This present paper tries to evaluate the role of E-HRM in IT companies and also to measure the acceptance and effectiveness of the same at the different levels of management.

scholarly journals TRADITIONAL DWELLING OF M`ZAB VALLEY IN ALHERIA: THE POINT OF ADAPTATION TO THE ENVIREMENT

2021 ◽  
pp. 159-169
Author(s):  
Nourel Houda Rezig
Keyword(s):  
Renewable Resources ◽  
Social Values ◽  
Arid Environment ◽  
Arid Climate ◽  
Simple Design ◽  
Unesco World Heritage ◽  
Sustainability Strategies ◽  
Local Materials ◽  
Different Levels ◽  
Passive Techniques

The article deals with the traditional dwellings in the UNESCO World Heritage ancient settlements (ksour) of M’zab Valley in Algerian desert. The Mozabite habitats are reflection of cultural and social values embodied in the architecture, with simple design in their forms deep in their indications, they are organized with a set of principles and rules known as customs that were inspired by religion and adapted to the environment. This latter helped to preserve Mozabite dwellings for more than a millennium. In this article the attention has been drawn to the dwelling’s design and distribution of its spaces according the activities and lifestyle of Mozabite community considering the arid environment needs. Sustainability strategies have significant presence in different levels of the dwelling appearing from the usage of passive techniques which depend on the principles of conservation energy and water, exploiting renewable resources and usage of local materials. These techniques are what make dwellings integrate completely within arid climate.

Structural-Acoustic Optimization of Sandwich Panels

2005 ◽  
Author(s):  
Francesco Franco ◽  
Kenneth A. Cunefare ◽  
Massimo Ruzzene
Keyword(s):  
Numerical Optimization ◽  
Composite Structures ◽  
Gradient Methods ◽  
Sandwich Panels ◽  
Relative Importance ◽  
Structural Elements ◽  
Acoustic Response ◽  
The Core ◽  
Design Flexibility ◽  
The Face

Sandwich panels, comprising face sheets enclosing a core, are increasingly common structural elements in a variety of applications, including aircraft fuselages and flight surfaces, vehicle panels, lightweight enclosures, and bulkheads. The design flexibility associated with such composite structures provides significant opportunities for tailoring the structure to the load and dynamic response requirements for the particular application. Design flexibility encompasses the details of the face sheets and the core. This paper deals with the numerical optimization of different sandwich configurations for the purposes of achieving reduced structural acoustic response. Laminated face sheets and core geometries, comprising honeycomb and truss-like structures, are considered. The relative importance of the mass and stiffening properties of the core and face sheets are discussed. The optimization work is carried out using commercial codes. Benefits and limits of using an optimization algorithm based on gradient methods are highlighted.

scholarly journals Systematic Integration of Energy-Optimal Buildings With District Networks

Energies ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2945 ◽  
Author(s):  
Raluca Suciu ◽  
Paul Stadler ◽  
Ivan Kantor ◽  
Luc Girardin ◽  
François Maréchal
Keyword(s):  
Low Temperature ◽  
Operating Cost ◽  
Urban Systems ◽  
Mixed Integer ◽  
Fourth Generation ◽  
Low Carbon ◽  
Energy Networks ◽  
First Case ◽  
Investment Cost

The residential sector accounts for a large share of worldwide energy consumption, yet is difficult to characterise, since consumption profiles depend on several factors from geographical location to individual building occupant behaviour. Given this difficulty, the fact that energy used in this sector is primarily derived from fossil fuels and the latest energy policies around the world (e.g., Europe 20-20-20), a method able to systematically integrate multi-energy networks and low carbon resources in urban systems is clearly required. This work proposes such a method, which uses process integration techniques and mixed integer linear programming to optimise energy systems at both the individual building and district levels. Parametric optimisation is applied as a systematic way to generate interesting solutions for all budgets (i.e., investment cost limits) and two approaches to temporal data treatment are evaluated: monthly average and hourly typical day resolution. The city center of Geneva is used as a first case study to compare the time resolutions and results highlight that implicit peak shaving occurs when data are reduced to monthly averages. Consequently, solutions reveal lower operating costs and higher self-sufficiency scenarios compared to using a finer resolution but with similar relative cost contributions. Therefore, monthly resolution is used for the second case study, the whole canton of Geneva, in the interest of reducing the data processing and computation time as a primary objective of the study is to discover the main cost contributors. The canton is used as a case study to analyse the penetration of low temperature, CO2-based, advanced fourth generation district energy networks with population density. The results reveal that only areas with a piping cost lower than 21.5 k/100 m2ERA connect to the low-temperature network in the intermediate scenarios, while all areas must connect to achieve the minimum operating cost result. Parallel coordinates are employed to better visualise the key performance indicators at canton and commune level together with the breakdown of energy (electricity and natural gas) imports/exports and investment cost to highlight the main contributors.

scholarly journals Influencing Factors on Aesthetics: Highly Controlled Study Based on Eye Movement and the Forensic Aspects in Computer-Based Assessment of Visual Appeal in Upper Front Teeth

2021 ◽  
Vol 11 (15) ◽  
pp. 6797
Author(s):  
Monika Bjelopavlovic ◽  
Michael Weyhrauch ◽  
Christina Erbe ◽  
Franziska Burkard ◽  
Katja Petrowski ◽  
...  
Keyword(s):  
Tracking System ◽  
Dental Student ◽  
Controlled Study ◽  
External Appearance ◽  
Dental Esthetics ◽  
Anterior Teeth ◽  
The Face ◽  
Overall Evaluation ◽  
Computer Based ◽  
Different Levels

First impressions are formed by the external appearance and, in this respect, essentially by an examination of the face. In the literature, the teeth, especially the maxillary front, are among an eye-catching and sensitive area that plays a significant role in the overall evaluation of appearance. In this study, the first eye fixation of 60 subjects with different levels of dental training (layperson, trained layperson, dental student, and dentist) is recorded using an eye-tracking system, and their subsequent evaluation of the images is recorded. Ten unedited original photographs of different maxillary anterior teeth and ten subsequently edited photographs will be used to evaluate forensic aspects such as the effect of symmetry and color on the overall evaluation. The results will be used to determine which areas of the maxillary anterior are demonstrably viewed and whether knowledge of dental esthetics influences evaluation and viewing.

scholarly journals Estratégias de enfrentamento à pandemia por COVID-19: subsídios à enfermagem

2021 ◽  
Vol 11 (34) ◽  
pp. 384-387
Author(s):  
Agostinho Porfírio dos Santos ◽  
Rosely Leyliane dos Santos
Keyword(s):  
Health Care ◽  
Health Promotion ◽  
Social Distance ◽  
Infection Prevention ◽  
Nursing Practice ◽  
Prevention And Health Promotion ◽  
Uso De Alcohol ◽  
The Face ◽  
Promotion Strategies ◽  
Different Levels

Objetivou-se conhecer acerca das estratégias de enfrentamento frente à pandemia de COVID-19. Trata-se de estudo do tipo comentário breve, construído com base na leitura de artigos científicos que atendessem a questão norteadora: Quais estratégias podem ser utilizadas para enfrentamento da COVID-19? Os materiais selecionados oportunizaram a construção da categoria: “Estratégias individuais e coletivas para enfrentamento da COVID-19: subsídios para a prática de enfermagem”. Os resultados apontam que as estratégias incluem medidas individuais e coletivas como distanciamento social, higienização das mãos, uso de álcool-gel, limpeza e desinfecção das superfícies, contenção viral à redução da transmissibilidade, vigilância dos casos e educação sanitária. Estas ações são essenciais para nortear a prática de enfermagem em âmbitos individual e coletivo, nos diferentes níveis de atenção em saúde. As estratégias evidenciadas frente à COVID-19 são ferramentas essenciais à atuação de enfermagem bem como para mitigar o ciclo infeccioso do vírus.Descritores: Promoção da Saúde, Infecções por Coronavírus, Pandemias. Strategies for coping with the covid-19 pandemic: subsidies to nursingAbstract: The objective was to learn about strategies in the face of the COVID-19 pandemic. This is a brief commentary type study, based on reading scientific studies that answered the guiding question: What strategies can be used to prevent COVID-19? The selected articles enabled the construction of the category: “Individual and collective strategies for the prevention of COVID-19: subsidies for nursing practice”. The results showed that disease prevention and health promotion strategies, which can support nursing practice, include individual and collective measures such as social distance, hand hygiene, use of alcohol-gel, cleaning and disinfecting surfaces, viral containment to reduction transmissibility, case surveillance and health education. These actions are essential in order to guide nursing practice in individual and collective spheres at different levels of health care. Infection prevention and health promotion strategies in the face of COVID-19 are essential tools for nursing practice in order to mitigate the virus's infectious cycle.Descriptores: Health Promotion, Coronavirus Infections, Pandemics. Estrategias para hacer frente a la pandemia del covid-19: subsidios a la enfermeríaResumen: El objetivo era conocer las estrategias de afrontamiento ante la pandemia de COVID-19.  Es un breve estudio de comentários, basado en la lectura de artículos científicos que respondieron a la cuestión orientadora: ¿Qué estrategias se pueden usar para prevenir COVID-19? Los artículos seleccionados permitieron construir la categoría: "Estrategias individuales y colectivas para la prevención de COVID-19: subsidios para la práctica de enfermería". Las estrategias de prevención de enfermedades y promoción de la salud, que pueden apoyar la práctica de enfermería, incluyen medidas individuales y colectivas como distancia social, higiene de manos, uso de alcohol en gel, limpieza y desinfección de superficies, contención viral para reducir transmisibilidad, vigilancia de casos y educación sanitaria. Estas acciones son esenciales para guiar la práctica de enfermería en las esferas individuales y colectivas en los diferentes niveles de atención médica. La prevención de infecciones y las estrategias de promoción de la salud frente a COVID-19 son herramientas esenciales para la práctica de enfermería a fin de mitigar el ciclo infeccioso del virus. Los estudios están en progreso ya que la cura para la enfermedad es un desafío.Descriptors: Promoción de la Salud, Infecciones por Coronavirus, Pandemias.

scholarly journals The roles of standing genetic variation and evolutionary history in determining the evolvability of anti-predator strategies

2014 ◽  
Author(s):  
Jordan Fish ◽  
Daniel R O'Donnell ◽  
Abhijna Parigi ◽  
Ian Dworkin ◽  
Aaron P Wagner
Keyword(s):  
Genetic Variation ◽  
Evolutionary History ◽  
Relative Importance ◽  
Digital Evolution ◽  
Relative Ease ◽  
Evolutionary Response ◽  
Two Factors ◽  
The Face ◽  
Evolutionary Trajectories ◽  
Different Levels

Standing genetic variation and the historical environment in which that variation arises (evolutionary history) are both potentially significant determinants of a population’s capacity for evolutionary response to a changing environment. We evaluated the relative importance of these two factors in influencing the evolutionary trajectories in the face of sudden environmental change. We used the open-ended digital evolution software Avida to examine how historic exposure to predation pressures, different levels of genetic variation, and combinations of the two, impact anti-predator strategies and competitive abilities evolved in the face of threats from new, invasive, predator populations. We show that while standing genetic variation plays some role in determining evolutionary responses, evolutionary history has the greater influence on a population’s capacity to evolve effective anti-predator traits. This adaptability likely reflects the relative ease of repurposing existing, relevant genes and traits, and the broader potential value of the generation and maintenance of adaptively flexible traits in evolving populations.

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