A case study of Siemens Afghanistan : building a country, building a company

This case study was written within the broader concept of Organisational Culture and how it is integrated into an organisation to encourage responsible leadership. The core focus and emphasis of this approach is to establish the implications for businesses operating in the most challenging of commercial environments, while adhering to their corporate ethos and organisational values. These may be summarised with the phrase: Only a clean business is a sustainable business. This dissertation is intended to act as a case study and resource aide for the teaching of leadership, organisational behaviour, human resources and business sustainability. The study is about the Afghanistan chapter of the global giant Siemens, which has been working in many areas of specialisation conducting business in the country for more than 75 years. It has been selected for this case study because of its long-term impressive record, during which time it has developed and sustained a reputation as an organisation with a much-admired organisational culture, and one to which employees feel very closely attached and connected. This case study evolved from a set of unique as well as difficult circumstances. In Afghanistan, where infrastructure is weak, businesses and other structured organisations are in their initial and immature stages of development, and employee attachment to their workplaces is relatively weak. In the case of Siemens however, it has been much the opposite. It became apparent over a protracted period of time that the relationship of employees to the company was clearly of a positive and committed nature, unlike the general perception stemming from other multinational organisations operating within the country. Many business organisations in Afghanistan tend to emphasise to a lesser degree some modern-day practices of employer-employee relationships, which negatively affect motivation and commitment. The study grew out of the observations that employees of Siemens on the other hand, seemed to exhibit attitudes and commitments contrary to the general trend in the wider business sector. This project began with the intention to identify those factors contributing to employee loyalty and strong attachments to an organisation. Subsequently, the same findings were used to identify the traits and particular features working within the organisational environment

Fast MCMC sampling algorithms on polytopes

We propose and analyze two new MCMC sampling algorithms, the Vaidya walk and the John walk, for generating samples from the uniform distribution over a polytope. Both random walks are sampling algorithms derived from interior point methods. The former is based on volumetric-logarithmic barrier introduced by Vaidya whereas the latter uses John's ellipsoids. We show that the Vaidya walk mixes in significantly fewer steps than the logarithmic-barrier based Dikin walk studied in past work. For a polytope in $\mathbb{R}^d$ defined by $n >d$ linear constraints, we show that the mixing time from a warm start is bounded as $\mathcal{O}(n^{0.5}d^{1.5})$, compared to the $\mathcal{O}(nd)$ mixing time bound for the Dikin walk. The cost of each step of the Vaidya walk is of the same order as the Dikin walk, and at most twice as large in terms of constant pre-factors. For the John walk, we prove an $\mathcal{O}(d^{2.5}\cdot\log^4(n/d))$ bound on its mixing time and conjecture that an improved variant of it could achieve a mixing time of $\mathcal{O}(d^2\cdot\text{polylog}(n/d))$. Additionally, we propose variants of the Vaidya and John walks that mix in polynomial time from a deterministic starting point. The speed-up of the Vaidya walk over the Dikin walk are illustrated in numerical examples.Comment: 86 pages, 9 figures, First two authors contributed equall

Congestion Control for Wireless Ad-Hoc Networks

We study joint design of end-to-end congestion control and Per-link medium access control (MAC) in ad-hoc networks. In the current scenario wireless communication is emerging the world. Wireless Ad Hoc networks demands for higher intermediate node supports for long-range communication. Wireless Ad Hoc network is an emerging communication approach. Ad Hoc networks are usually defined as an autonomous system of nodes connected by wireless links and communicating in a multi-hop fashion. The wireless ad-hoc networks are for easy of deployment without centralized administration or fixed infrastructure, to achieve the goal of less interference communication. In wireless Ad-hoc network the connections between the wireless links are not fixed but dependent on channel conditions as well as the specific medium access control (MAC). The channel medium and transmission links are affected by the interference, delay, and buffer overflow these may cause the network congestion. To avoid network congestion various congestion control methods were developed in past but they were performed less control of end-to-end congestion and less in per link connection control. To overcome the above problems and to improve the resource allocation an efficient method has to be developed

Revisiting complexity and the bias-variance tradeoff

The recent success of high-dimensional models, such as deep neural networks (DNNs), has led many to question the validity of the bias-variance tradeoff principle in high dimensions. We reexamine it with respect to two key choices: the model class and the complexity measure. We argue that failing to suitably specify either one can falsely suggest that the tradeoff does not hold. This observation motivates us to seek a valid complexity measure, defined with respect to a reasonably good class of models. Building on Rissanen's principle of minimum description length (MDL), we propose a novel MDL-based complexity (MDL-COMP). We focus on the context of linear models, which have been recently used as a stylized tractable approximation to DNNs in high-dimensions. MDL-COMP is defined via an optimality criterion over the encodings induced by a good Ridge estimator class. We derive closed-form expressions for MDL-COMP and show that for a dataset with $n$ observations and $d$ parameters it is \emph{not always} equal to $d/n$, and is a function of the singular values of the design matrix and the signal-to-noise ratio. For random Gaussian design, we find that while MDL-COMP scales linearly with $d$ in low-dimensions ($d<n$), for high-dimensions ($d>n$) the scaling is exponentially smaller, scaling as $\log d$. We hope that such a slow growth of complexity in high-dimensions can help shed light on the good generalization performance of several well-tuned high-dimensional models. Moreover, via an array of simulations and real-data experiments, we show that a data-driven Prac-MDL-COMP can inform hyper-parameter tuning for ridge regression in limited data settings, sometimes improving upon cross-validation.Comment: First two authors contributed equally. 28 pages, 11 Figure

Skill of the craft - a key to optimizing worker productivity and job safety

This guide provides a basis for using the skill of the craft during work planning and performance. The principles in the guide can be applied to the wide range of tasks and work environments found at Hanford. The basis for this guide is DOE 4330.4B, Maintenance Management Program. This order describes the program elements for maintenance at DOE nuclear and non-nuclear facilities. It emphasizes an integrated maintenance philosophy and culture based on good stewardship and established industrial maintenance principles

Diabetic Cardiovascular Disease Induced by Oxidative Stress.

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality among patients with diabetes mellitus (DM). DM can lead to multiple cardiovascular complications, including coronary artery disease (CAD), cardiac hypertrophy, and heart failure (HF). HF represents one of the most common causes of death in patients with DM and results from DM-induced CAD and diabetic cardiomyopathy. Oxidative stress is closely associated with the pathogenesis of DM and results from overproduction of reactive oxygen species (ROS). ROS overproduction is associated with hyperglycemia and metabolic disorders, such as impaired antioxidant function in conjunction with impaired antioxidant activity. Long-term exposure to oxidative stress in DM induces chronic inflammation and fibrosis in a range of tissues, leading to formation and progression of disease states in these tissues. Indeed, markers for oxidative stress are overexpressed in patients with DM, suggesting that increased ROS may be primarily responsible for the development of diabetic complications. Therefore, an understanding of the pathophysiological mechanisms mediated by oxidative stress is crucial to the prevention and treatment of diabetes-induced CVD. The current review focuses on the relationship between diabetes-induced CVD and oxidative stress, while highlighting the latest insights into this relationship from findings on diabetic heart and vascular disease