Changes in settlement pattern and culture - the process of down-hill migration in Tula, Bauchi State

The process of down-hill migration of the Tula people started during the 1920s and has not yet finished. The resulting present situation might give information how far terraces play any role in the economy, ecology and ideology of the Tula. Approaching this question from a socio-agricultural point of view some facts which indicate the pertaining or overcoming of traditional structures will be presented. In the following the land tenure system, the adoption of innovations and the role of women in agriculture will be discussed comparatively for Tula Wange and Tula Baule on the plateau, Fantami, which is generated by down-hill dwellers of Tula Wange, with its more or less bad farming conditions on shallow sandy soils and Kaltin, where the down migrants of Tula Baule settle in a more fertile area. Tula Wange numbers around 2000 households, Baule 1000, Fantami about 200 and Kaltin 350 of which the sample survey includes 15% in the plateau sites and 25% in the plain settlements

National Culture\u27s Impact on Effectiveness of Supply Chain Disruption Management

The purpose of this research is to understand the national cultural antecedents that may help explain differences in supply chain disruptions mitigation abilities of companies from different countries. An analysis of survey data on disruption planning and response collected from various organizations worldwide was performed using weighted least square regression and factor analysis. We find that culture influences disruption planning and response. Statistical findings suggest that differences in disruption planning and response abilities between companies from different countries could be partly attributed to national culture. All five Hofstede’s dimensions of national culture, i.e., Power Distance, Individualism, Masculinity, Uncertainty Avoidance, and Long-term Orientation were shown to have a significant positive effect on disruption planning and response. National cultural dimensions and economic status of a country could be effectively used to predict disruption planning and response abilities of companies in various countries. Managers could benefit from our research as it could help them assess disruptions mitigation abilities of their partners located in other countries. Increasing international trade and globalization of supply chains accentuate the importance of our research

Demand Management in Decentralized Logistics Systems and Supply Chains

We analyze issues arising from demand management in decentralized decision-making environments. We consider logistics systems and supply chains, where companies' operations are handled with independent entities whose decisions affect the performance of the overall system. In the first study, we focus on a logistics system in the sea cargo industry, where demand is booked by independent sales agents, and the agents' capacity limits and sales incentives are determined by a central headquarters. We develop models for the central headquarters to analyze and optimize capacity allocation and sales incentives to improve the performance of the decentralized system. We use network flow problems to incorporate agent behavior in our models, and we link these individual problems through an overall optimization problem that determines the capacity limits. We prove a worst-case bound on the decentralized system performance and show that the choice of sales incentive impacts the performance. In the second study, we focus on supply chains in the automotive industry, where decentralization occurs as a result of the non-direct sales channels of the auto manufacturers. Auto manufacturers can affect their demand through sales promotions. We use a game theoretical model to examine the impact of retailer incentive and customer rebate promotions on the manufacturer's pricing and the retailer's ordering/sales decisions. We consider several models with different demand characteristics and information asymmetry between the manufacturer and a price discriminating retailer. We characterize the subgame-perfect Nash equilibrium decisions and determine which promotion would benefit the manufacturer under which market conditions. We find that the retailer incentives are preferred when demand is known. On the other hand, when demand is highly uncertain the manufacturer is better off with customer rebates. We extend this research by analyzing a competitive setting with two manufacturers and two retailers, where the manufacturers' promotions vary between retailer incentives and customer rebates. We find an equilibrium outcome where customer rebates reduce the competitor's profits to zero. We observe in numerical examples that the manufacturers are able to increase their sales and profits with retailer incentives, although this can be at the expense of the retailers' profits under some situations.Ph.D.Committee Chair: Swann, Julie; Committee Member: Ergun, Ozlem; Committee Member: Ferguson, Mark; Committee Member: Griffin, Paul; Committee Member: Keskinocak, Pina

Modeling Electrical Resistance Drift with Ultrafast Saturation of OTS Selectors

Crossbar array architecture is an essential design element for densely connected Non-Volatile Memory(NVM) applications. To overcome intrinsic sneak current problem of crossbar arrays, each memory unit is serially attached to a selector unit with highly nonlinear current-voltage (I-V) characteristics. Recently, Ovonic Threshold Switching (OTS) materials are preferred as selectors due to their fabrication compatibility with PRAM, MRAM or ReRAM technologies; however, OTS selectors suffer from the temporal drift of its threshold voltage. First, based on Poole-Frenkel conduction, we present time and temperature dependent model that predicts temporally evolving I-V characteristics,including threshold voltage of OTS selectors. Second, we report an ultrafast saturation (∼103 seconds) of the drift and extend the model to predict the time of drift saturation. Our model shows excellent agreement with OTS devices fabricated with 8 nm technology node at 25°C and 85°C ambient temperatures. The proposed model plays a significant role in understanding OTS device internals and the development of reliable threshold voltage jump table

La perception de l'environnement et les migrations chez les pasteurs Peuls du Nigeria, Burkina Faso et Bénin

Dans les sociétés peules, des migrations de toutes dimensions jouent traditionnellement un rôle très important. Elles sont le résultat d’un processus complexe de prise de décision. Notre contribution vise à fournir des informations sur les motifs qui influencent ces décisions, et à partir de quels concepts ces motifs sont générés. Un élément central dans ce processus est l’environnement. S’il y a quelque peu un environnement ou une culture peule homogène, il n’y a cependant pas de conception peule de l’environnement. Leur conception est modifiée lors de chaque intégration des Peuls dans un nouvel environnement. Migrer signifie se rendre dans un nouvel environnement, où les concepts existants doivent par conséquent être adaptés aux nouvelles conditions. Par la suite, nous allons montrer à l’exemple des Peuls agropastoraux de différents milieux naturels et sociaux du Burkina Faso, Bénin et Nigeria dans quelle mesure les connaissances de l’environnement peuvent influencer les décisions migratoires. A l’exemple de la végétation, on examinera à travers quels concepts cet environnement, plus précisément l’environnement physique, est classifié et évalué. Finalement il sera présenté comment les migrations influencent les concepts environnementaux et comment ceux-là se reflètent dans la langue