IRR: A Blind Guide

Over the past 60 years the internal rate of return (IRR) has become a major tool in investment evaluation. Many executives prefer it to net present value (NPV), presumably because they can more easily comprehend a percentage measure. This article demonstrates that, except in the rare case of an investment that is followed by a single cash return, IRR suffers from a definitional quandary. Is it an intrinsic measure, defined only in terms of itself, or is it defined by the efforts of active investors? Additionally, the article explains significant problems with the measure - reinvestment issues, multiple IRRs, timing problems, problems of choice among unequal investment opportunities, and practical difficulties with multiple discount rates. IRR is a blind guide because its definition is in doubt and because of its many practical problems

Blind guide: anytime, anywhere

Sight dominates our mental life, more than any other sense. Even when we are just thinking about something the world, we end imagining what looks like. This rich visual experience is part of our lives. People need the vision for two complementary reasons. One of them is vision give us the knowledge to recognize objects in real time. The other reason is vision provides us the control one need to move around and interact with objects. Eyesight helps people to avoid dangers and navigate in our world. Blind people usually have enhanced accuracy and sensibility of their other natural senses to sense their surroundings. But sometimes this is not enough because the human senses can be affected by external sources of noise or disease. Without any foreign aid or device, sightless cannot navigate in the world. Many assistive tools have been developed to help blind people. White canes or guide dogs help blind in their navigation. Each device has their limitation. White canes cannot detect head level obstacles, drop-offs, and obstructions over a meter away. The training of a guide dog takes a long time, almost five years in some cases. The sightless also needs training and is not a solution for everybody. Taking care of a guide dog can be expensive and time consuming. Humans have developed technology for helping us in every aspect of our lives. The primary goal of technology is helping people to improve their quality of life. Technology can assist us with our limitations. Wireless sensor networks is a technology that has been used to help people with disabilities. In this dissertation, the author proposes a system based on this technology called Blind Guide. Blind Guide is an artifact that helps blind people to navigate in indoors or outdoors scenarios. The prototype is portable assuring that can be used anytime and anywhere. The system is composed of wireless sensors that can be used in different parts of the body. The sensors detect an obstacle and inform the user with an audible warning providing a safety walk to the users. A great feature about Blind Guide is its modularity. The system can adapt to the needs of the user and can be used in a combination with other solution. For example, Blind Guide can be used in conjunction with the white cane. The white cane detects obstacles below waist level and a Blind Guide wireless sensor in the forehead can detect obstacles at the head level. This feature is important because some sightless people feel uncomfortable without the white cane. The system is scalable giving us the opportunity to create a network of interconnected Blind Guide users. This network can store the exact location and description of the obstacles found by the users. This information is public for all users of this system. This feature reduces the time required for obstacle detection and consequent energy savings, thus increasing the autonomy of the solution. One of the main requirements for the development of this prototype was to design a low-cost solution that can be accessible for anyone around the world. All the components of the solution can provide a low-cost solution, easily obtainable and at a low cost. Technology makes our life easier and it must be available for anyone. Modularity, portability, scalability, the possibility to work in conjunction with other solutions, detecting objects that other solutions cannot, obstacle labeling, a network of identified obstacles and audible warnings are the main aspects of the Blind Guide system. All these aspects makes Blind Guide an anytime, anywhere solution for blind people. Blind Guide was tested with a group of volunteers. The volunteers were sightless and from different ages. The trials performed to the system show us positive results. The system successfully detected incoming obstacles and informed in real time to its users. The volunteers gave us a positive feedback telling that they felt comfortable using the prototype and they believe that the system can help them with their daily routine

Comparison between audio and tactile systems for delivering simple navigational information to visually impaired pedestrians

Many of the current GPS (Global Positioning Systems) navigation aids use an audio method to deliver navigation information to the user. For the visually impaired person this method can be problematic. The visually impaired pedestrian relies heavily on information contained within the ambient sound environment; for location and orientation information, navigation information, and importantly, safety information. In this paper we present the design of an innovative tactile interface and verification of results obtained through experimental trials. This pilot study compared the efficiency of the tactile interface, to an audio method of delivering simple navigational information. The findings indicate that the tactile interface could be used successfully by blind and sighted pedestrians and may offer advantages over auditory interfaces

Values, Leadership and Ministry: From Blind Guide to Reflective Practitioner

Coming into contact with key principles in Management Science as part of a course of study towards a Doctorate of Ministry led the author to consider the possibilities of an interface between the discipline of reflective practice and spirituality. Engaging with concepts such as Action Science, ‘skilled incompetance’ and communities of practice enabled him to approach challenging situations within a church setting with a fresh outlook and provided tools with which to attempt to resolve them. Models of pastoral supervision, reflective practice and forming teams and communities by covenanting together are also explored

AmIE: An Ambient Intelligent Environment for Assisted Living

In the modern world of technology Internet-of-things (IoT) systems strives to provide an extensive interconnected and automated solutions for almost every life aspect. This paper proposes an IoT context-aware system to present an Ambient Intelligence (AmI) environment; such as an apartment, house, or a building; to assist blind, visually-impaired, and elderly people. The proposed system aims at providing an easy-to-utilize voice-controlled system to locate, navigate and assist users indoors. The main purpose of the system is to provide indoor positioning, assisted navigation, outside weather information, room temperature, people availability, phone calls and emergency evacuation when needed. The system enhances the user's awareness of the surrounding environment by feeding them with relevant information through a wearable device to assist them. In addition, the system is voice-controlled in both English and Arabic languages and the information are displayed as audio messages in both languages. The system design, implementation, and evaluation consider the constraints in common types of premises in Kuwait and in challenges, such as the training needed by the users. This paper presents cost-effective implementation options by the adoption of a Raspberry Pi microcomputer, Bluetooth Low Energy devices and an Android smart watch.Comment: 6 pages, 8 figures, 1 tabl

Scemare, or Approaching “Virgillessness”

Any examination of the phenomenon of absence in the Commedia must account for a crucial linguistic issue: though they are amply attested in the Commedia’s sources, the words assenza, assente, and their derivatives are themselves conspicuously absent from the poem’s lexicon. Absence experiences are expressed in the poem partly through imagery and circumlocution, but also through a constellation of individual words which invoke experiences of absence without naming absence as such. One particularly suggestive word operating within this language of omission is the verb scemare. With a focus on Purgatorio 30, in this paper, I discuss the importance of scemare to Dante’s lexicon of exclusion, and the ways in which it shapes our experience and understanding of absence in the Commedia more broadly

Single stage experimental evaluation of variable geometry guide vanes and stators. Part 1 - Analysis and design

Variable geometry concepts applied to guide vanes and stators in single stage compressor