As organizações virtuais (OVs) se apresentam como uma forma promissora de cooperação entre empresas. Tal forma de organização permite criar um ambiente propício às pequenas e médias empresas que almejam obter acesso a novos mercados e a novas oportunidades de negócios. A função principal das OVs é tornar possível a rápida formação de Empresas Virtuais, que são alianças temporárias entre os componentes de uma OV. O objetivo dessas alianças é explorar oportunidades de negócios específicas, compartilhando habilidades, custos, riscos, infra-estrutura, pesquisa e desenvolvimento. Como toda organização, uma OV necessita formar estratégias que estabeleçam caminhos para atingir seus objetivos organizacionais. No entanto, existe uma carência de métodos e processos de formação de estratégias, adequados à estrutura e às características desse tipo não tradicional de organização. O objetivo deste trabalho é propor um modelo de referência para a formação de estratégias em Organizações Virtuais. Para elaborar o modelo são expostas as várias abordagens relacionadas à formação de estratégias nas organizações tradicionais e determinadas suas adequações à estrutura e às características das OVs. Por fim, o modelo proposto é validado e uma OV real. / The Virtual Organizations (VOs) are presented as a promising way of cooperation between companies. Such a forma of organization allows building a favorable environment to small-medium enterprises that wish to have access to new markets and new business opportunities. The main function of a VO is to make the quick configuration of Virtual Enterprises (VEs), which are temporary alliances between VO partners. The objective of these alliances is to exploit specific opportunities sharing skills, costs, risks, infrastructure, research and development. As all organizations, VOs need to form strategies to establish ways to reach their organizational goals. However, there is a lack of proper methods and processes related to the formation of stategies that adapt to the structure and features of this non-tradicional kind of organization. The goal of this work is to propose a reference model of strategies formation in Virtual Organizations. To elaborate the model, various approaches related to strategy formation in traditional organizations are exposed and established their adequacy to the structure and features of VOs. At last, the model proposed is validated in a real VO.

Con el presente trabajo se pretende determinar si mediante la utilización de la plataforma de enseñanza virtual Chamilo, mejora el rendimiento académico de alumnos del curso de Ciencias Naturales, segundo grado del nivel secundaria, en el tercer bimestre 2018 en la Institución Educativa. Harvard, Huancayo. Para lo cual se implementó una plataforma de enseñanza virtual Chamilo, diseñando una propuesta de mejora en el desarrollo de la enseñanza aprendizaje a aplicarse al curso de Ciencias Naturales. El diseño de la investigación fue experimental, mediante el promedio de notas de evaluaciones del segundo bimestre (Pre-test) y tercer bimestre (Pos-test), para 1 sección, se tomó una muestra de 30 alumnos. La variable analizada fue la mejora del rendimiento académico mediante el autoaprendizaje. Luego de 6 semanas de prueba, los resultados comparativos entre las notas del 2do y el 3er bimestre, demostró que el uso de la plataforma Chamilo, logró incrementar el puntaje en mayor medida.

The purpose of this research is the creation of the framework for immersive Virtual Worlds (VW) development and evaluation of factors affecting user’s immersion experience in 3D virtual worlds. Three experiments have been conducted to evaluate different aspects of the immersion experience in virtual reality. The first experiment aimed to explore the influence of communication on users whilst performing certain activities in a virtual world. The second experiment evaluated how the real-world environment affects users in a virtual world. The third experiment examined the aspect of mobility as a main contributor to a user’s distraction. The fourth experiment partly confirmed previous findings and added new factors, affecting immersion experience. The results of all experiments formed a framework, containing factors which users considered as affecting them during their activities in virtual worlds. During the experimentation phase of this research a combination of qualitative and quantitative methods was used. The Grounded Theory (GT) methodology was applied for data analysis in qualitative part. The major contribution of this research is the framework of factors for building immersive 3D virtual environments. Another contribution is the evaluation of factors affecting users in such an environment.

<div>The use of virtual reality technologies in education and training can provide an opportunity to reduce training costs while increasing the attractiveness and safety for trainees in the manufacturing industry. This thesis strives to show a virtual world which is based upon real world imagery can be embedded in a virtual reality environment and augmented with underlying real world mathematical models to show in real time the consequences of user selected parameters on a running manufacturing process.</div><div>An interactive virtual operator training environment is presented utilizing a VR headset in conjunction with a VR gaming engine which supports the headset and also embeds the behavior details of the underlying manufacturing process.</div><div>To demonstrate this approach an example is developed based on a steel industry roughing mill in which steel slabs are ultimately rolled into coils. This example shows the software application development process given as applied to an interactive training simulator intended for plant operator training which includes the use of the gaming engine Unity 3D, 360-degree video, 3Ds Max and several other software tools.</div><div>The resulting example is a controllable model of the steel plant roughing mill which can be used to enhanced the knowledge of plant operational personnel as to the effects various operating parameters have on the final rolled product while enhancing the understanding of this mill operation for new plant operators.</div>

Virtual knot theory is an extension of classical knot theory based on a combinatorial presentation of crossing information. The appropriate extensions of braid groups and string link monoids have also been studied. While some previously known knot invariants can be evaluated for virtual objects, entirely new techniques can also be used, for example, the concept of index of a crossing, and its resulting (Gaussian) parity theory. In general, a parity is a rule which assigns 0 or 1 to each crossing in a knot or link diagram. Recently, they have also been defined for virtual braids. Here, novel parities for knots, braids, and string links are defined, some of their applications are explored, most notably, defining a new subgroup of the virtual braid groups. / Thesis / Master of Science (MSc)

MSc(Eng),School of Civil and Environmental Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand, 2010 / This dissertation presents a new method for the automated optimisation of structures. The method has been developed to: (1) select sections to satisfy strength and deflection requirements using minimum material, and (2) efficiently group members. The member selection method is based on the principle of virtual work, and is called the Virtual Work Optimisation (VWO) method. It addresses multiple deflection and load case constraints simultaneously. The method determines which sections provide the highest deflection and strength resistance per unit mass. When compared to several other methods in the literature, and designs from industry, the VWO method produced savings of up to 15.1%. A parametric investigation of ungrouped, multi-storey frames is conducted using the VWO method to determine optimal mass and stiffness distributions. Unusual mass patterns have been found. Diagonal paths of increased stiffness are formed in the frames, which suggests truss behaviour. A grouping algorithm is presented which determines how efficiently to create a specified number of groups in a structure. The VWO method has been incorporated into the automated algorithm to optimise the grouped structures. Members are grouped according to their mass per unit length. In the algorithm an exhaustive search of all feasible grouping permutations is carried out, and the lightest structure selected. Results produced are up to 5.9% lighter than those obtained using ad hoc grouping configurations found in the literature and based on experience.

Estágio realizado na empresa Volkswagem Autoeuropa e orientado pela Eng.ª Margarida Pereira / Tese de mestrado integrado. Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 2010

The use of Virtual Teams has become substantially more common place as the “global economy” has grown. Technology has enabled teams to collaborate across time and space, but can these teams perform as well or better than their co-located peers? The answer to this question is critical for companies considering offshoring or near shoring specific job functions. This question is also important for companies that require specialized resources that are unavailable in the local market place. The cost of relocating and centralizing specialized resources can be high and can be altogether avoided if virtual team performance is high. This paper addresses the performance question, discusses contingency factors impacting performance, and provides recommendations based both on the research and real world experience of the author / text

The ultimate goal in the manufacturing of a part is to achieve an economic production plan with precision and accuracy in the first attempt at machining. A physics-based comprehensive modeling of the machining processes is a fundamental requirement in identifying optimal cutting conditions which result in high productivity rates without violating accuracy throughout the part production process. This thesis presents generalized virtual simulation and optimization strategies to predict and optimize performance of milling processes up to 3-axis. Computationally efficient mathematical models are introduced to predict milling process state variables such as chip load, force, torque, and cutting edge engagement at discrete cutter locations. Process states are expressed explicitly as a function of helical cutting edge - part engagement, cutting coefficient and feedrate. Cutters with arbitrary geometries are modeled parametrically, and the intersection of helical cutting edges with workpiece features are evaluated either analytically or numerically depending on geometric complexity. The dynamics of generalized milling operations are modeled and the stability of the process is predicted using both time and frequency domain based models. These algorithms enable rapid simulation of milling operations in a virtual environment as the part features vary. In an effort to reduce machining time, a constraint-based optimization scheme is proposed to maximize the material removal rate by optimally selecting the depth of cut, width of cut, spindle speed and feedrate. A variety of user defined constraints such as maximum tool deflection, torque/power demand, and chatter stability are taken into consideration. Two alternative optimization strategies are presented: pre-process optimization provides allowable depth and width of cut during part programming at the computer aided manufacturing stage using chatter constraint, whereas the post-process optimization tunes only feedrate and spindle speed of an existing part program to maximize productivity without violating physical constraints of the process. Optimized feedrates are filtered by considering machine tool axes limitations and the algorithms are tested in machining various industrial parts. The thesis contributed to the development of a novel 3-axis Virtual Milling System that has been deployed to the manufacturing industry.

Increasingly, knowledge-based tasks such as new product development and market research are being conducted by geographically dispersed teams. Early evidence from knowledge-based view of the firm and geographically dispersed work literatures suggests that at least four kinds of knowledge gaps---transactive memory system, mutual knowledge, categorization and situated knowledge---exist because of the (dispersed) structure of the knowledge management context . Dispersed members therefore cannot take for granted that they have a common context, making dispersed collaboration problematic. / The dissertation - a qualitative, theory-generating exercise - seeks to address the question, 'how do dispersed teams collaborate to create useful knowledge?' Specifically, the research question examines the integral elements of the knowledge creation process, the negotiation of knowledge gaps for co-creating a common context, and the association between the negotiation of these gaps with the efficiency of the knowledge creation process, effectiveness of new knowledge created, and cohesion in the team. This research has been conducted in two phases - an exploratory ethnographic study followed by a replication study. / Analysis of the data instead directed my attention to the critical role of moderating variables such as degree of familiarity among dispersed team members, degree of redundancy of knowledge structures among them and the nature of task on the perceived presence or absence of gaps. These findings clarify the literature by differentiating between the structure and the properties of the knowledge management context and therefore develop a more comprehensive model of these moderating variables that have the potential to affect the dispersed knowledge creation process. Specifically, the findings demonstrate that degree of redundancy is positively associated with the efficiency of the knowledge creation process. These studies also suggest that dispersed collaboration may be less different from collocated collaboration than previously thought. Finally, these studies contribute to the dispersed work literature by suggesting that all kinds of dispersed work are not alike and face-to-face meetings may not be necessary for all types of dispersed work. / These findings are used to develop a theory of dispersed knowledge work and have implications for determining whether and in what contexts geographic distance matters for conducting knowledge work. One implication is that perceptions of distance may be at least as important as the objective aspects of distance. Another implication is that whether geographic distance matters will actually depend upon the competitive strategy of the firm.