Etude comparative de la rentabilité de deux types d'apiculture au Nord Ouest Cameroun

Comparative Study of the Profitability of Two Types of Bee Farming in the North West Cameroon. The present study examines the financial profitability of beekeeping in Cameroon. The global objective is to compare the profitability of two types of bee farms in the North West Region. The main hypothesis, however, is the following: there is a significant difference in output and in net benefit between traditional and semimodern bee farms. As regards the methodology used, a two stage stratified random sampling technique was used to select 100 bee farmers. Primary data was collected on elements of costs and revenue. The technique of cost benefit analysis was used to analyze the data. Findings showed that traditional beekeeping and semi-modern beekeeping (using Kenyan hives "KTBH") farms have an average production of 77.46 and 112.68 liters of honey per year respectively, for the respective average total revenue of 86 832.39 FCFA and 143 791 FCFA. The average annual value of their ratio Net Benefit/Total Cost is 1.168 and 1.193 respectively. The semi-modern bee hives perform better than the traditional one. Even with some difficulties faced by some farmers, bee farming in the North West Cameroon remains profitable. Despite the static character of this study, we suggest that beekeepers should adopt the semi-modern (Kenyan) hives

Development and Application of a Design Flow for Photonic Integrated Circuits

Silicon photonics allows for the fabrication of many optical elements on a single photonic integrated circuit (PIC). By taking advantage of the established foundry technology used in the CMOS and silicon’s high refractive index, high feature density manufacturing can be achieved in mass quantities. In CMOS fabrication, from conception of an electronic circuit to testing, the process of designing an electronic circuit is dictated by a design flow which has been developed over the course of decades. This flow includes circuit level design and simulation, layout of the circuit, layout and verification of the chip, fabrication, packaging, and testing. Given the identical fabrication technologies used in photonic and electronic circuit manufacturing, electronic design paradigms have been applied to photonic design. Current photonic design puts emphasis on physical layout with minimal simulation. Some post-layout verification exists but is unable to capture complex behavior such as optical and thermal cross-talk between photonic circuits. In addition, there is no design verification besides the traditional design rule check (DRC). To further develop the PIC design process, the need to fully characterize the current state of the photonic design flow is evident. In this work, a design flow is developed for photonic circuits fabricated through the American Institute for Manufacturing Integrated Photonics, or AIM Photonics. More specifically, this design flow has been developed for their Multi-Project Wafer (MPW) Process Design Kits (PDKs). A photonic circuit containing a ring resonator with a heater was designed and simulated using ANSYS Lumerical and laid out in Klayout, an open source layout software for photonic circuits, using the AIM Photonics PDK version 4.5a. This circuit was then characterized in an optics laboratory to compare its physical and simulated performance. Finally, through this comparison, we identified gaps in the current photonic layout and simulation tools as compared to electronic design automation (EDA)

Anaerobic digestion of crop and waste biomass: Impact of feedstock characteristics on process performance

Anaerobic digestion provides an array of positive environmental benefits such as reducing greenhouse gas emissions, replacing mineral fertilizers, producing renewable energy and treating waste. However, pitfalls in anaerobic digestion such as poor methane yields, process instability, process failure and regional shortages of feedstock have limited the full exploitation of the anaerobic digestion process. The research presented in this thesis deals with the assessment of the possible negative or positive impacts of feedstock characteristics on the efficiency of anaerobic digestion. In addition, it investigates ways of enhancing the methane yield of the feedstock by improving the feedstock characteristics. The feedstocks investigated were various energy crops, food industrial waste and sewage sludge. The improvement methods investigated were ensiling, nutrient supplementation, co-digestion and anaerobic pretreatment. It was found that ensiling crops results in insignificant losses in energy, total solid and wet weight. In addition, no significant difference was found in methane yields between the ensiled and fresh crop samples. The importance of correcting for losses of volatiles in total solids determination was pointed out and it was shown that failing to do so could be the main reason why many previous publications report increased total solid based methane yields after ensiling. Increased methane yield in silages may therefore be an effect of an analytical error rather than an effect of using ensiling as a pretreatment prior to anaerobic digestion. Anaerobic digestion of crop biomass is known to be particularly limited by nutrient availability. Direct nutrient supplementation in crop mono-digestion in this research demonstrated an efficient biogas process at the shorter hydraulic retention times commonly applied in co-digestion of crop biomass and manure. The high degradation efficiency was evidenced by high methane yields, comparable to maximum expected yields generated under controlled conditions, and low volatile fatty acids accumulation. As a result of nutrient addition, the digestate could comply with certification standards for bio-fertilizer. Also, viscosity problems commonly reported for crop mono-digestion were not observed in this study, which could be another effect of nutrient addition. Co-digesting of waste biomass and crop biomass led to significant improvement in methane yield per ton of feedstock and carbon to nitrogen ratio as compared to digestion of only the waste biomass. Biogas production from crops in combination with waste biomass also eliminated the need for addition of micronutrients normally required in crop mono-digestion. Co-digestion was also presented as a means of feedstock supplementation to curb feedstock shortages in waste-based anaerobic digestion processes. In addition, inhibitors in anaerobic digestion such as free ammonia and light metal ions were diluted, a condition which can lead to an overall viable biogas process Anaerobic pre-treatment led to the solubilisation of particulate organic matter in sewage sludge. This solubilisation could have led to the improved methane yield, methane production rate and reduction in volatile solids. Applying different feedstock improvement solutions to the various feedstocks investigated, i.e. nutrient addition, co-digestion and pretreatment, were demonstrated as effective means of enhancing the methane yield of the feedstock thereby improving the overall anaerobic digestion process

Profiling Attendees at a Major Women’s Football Event in Cameroon

The aim of this study is to profile attendees at a major women’s football event in Cameroon. The study is argued from the perspective that women’s football events have been a neglected phenomenon within the African context, and that there is a need for giving such events attention. Previous studies with regard to major football events have been biased towards developed contexts, as well as towards men’s events, while women’s events have received little attention. The research employs an explorative quantitative research design. A structured survey was used to generate 759 valid responses from attendees at the Africa Women Cup of Nations tournament in Cameroon. The study found that the majority of attendees at women’s football events are from the African region, travel in groups, usually stay at the destination for a relatively long time, and engage in post-event tourism activities. The results of the study have implications for the planning and development of major women football events, and contribute to the existing literature accordingly. The uniqueness of this paper lies in the researcher’s intention to add value to the literature regarding major women’s football events in the African context

Assessment of Food Security Status of Goat Farmers In Lagos State, Nigeria

The goat value chain plays a pivotal role in income and employment generation, livelihood enhancement; food and nutrition security among the poor, marginalized and disadvantaged groups and they are reared to supplement income and as a means of reducing food insecurity. The objective of this study is to assess the food security status of urban goat farmers in some local government areas of Lagos state, Nigeria. The use of qualitative method of data collection in the form of structured questionnaires were executed during the course of this study on a sample size of 80 goat farmers. Furthermore, during the course of the study, the specific objectives were analyzed using descriptive statistics as well as USDA food security code module. Using the Pearson’s rank correlation and binary logistic regression, the hypotheses were accurately tested to achieve results. From the result acquired, it was determined that men dominated women in the goat farming sector as well as revealing that the average age of respondents were 42.4 years. Furthermore, the results revealed that, about 65.4% of the respondents made an annual income ranging from 100,000-300,000 Naira and have been residents of the sample location for about 10-15 years. Another observation made from the results obtained during the course of this study showed that majority of the respondents practiced semi intensive system of management. This involves them using family labor (55.6%), having an average of 18.8 goats, as well as revealing sales as their main purpose of farming. More revelations from the result showed that, majority of the respondents were food insecure without hunger. Showing the major reasons for food insecurity to be insufficient finance, high cost of food and poor storage and processing. It was recommended that farmers be encouraged to belong to organizations such as cooperatives to solve problems in management and also for easy access or contact by government and extension agents

Analysis of the management competencies of goat farmers in some selected local government area of Lagos State Nigeria

This study focused on the analysis goat farmers’ management competency in ensuring sustainable production in some selected local government areas of Lagos state, Nigeria. A total of 80 goat farmers were sampled for the study with the aid of structured questionnaires which were used to collect data needed for the study. The objectives of this study were analyzed using descriptive statistics and the hypothesis was tested using binary logistic regression. The result showed that men dominated women in goat farming and that the average age of respondents was 42.4 years. It revealed that majority of the respondents (65.4%) made an annual income of 100,000-300,000 annually and had lived in the study area for 10-15 years. This study also showed that majority of the respondents practiced semi intensive system of management, used family labour (55.6%), the study further revealed that the goat farmers in the study area has low management competency with poor extension service, lack of pasture and graze land and prevalence of ectoparasite among the major challenges facing the goat farmers. It was recommended that farmers be encouraged to belong to organizations such as cooperatives to solve problems in management and government should revamp the extension service to improve service delivery to the farmers

A Study of the Nigerian Students Chinese Cultural Communication Problems

在汉语国际推广和中非合作战略的大背景下，越来越多的尼日利亚学生来到中国留学，但他们在中国文化环境下面临着诸多困难，文化差异和个人适应的问题成为影响在华尼日利亚学生语言习得和学习生活的重要问题，探讨解决跨文化交际困难的对策也成为日益紧迫的问题。本文重点考察在中国大学学习的尼日利亚人跨文化交际能力，通过文献梳理和实际的调查研究，寻找阻碍他们顺利融入中国社会的原因，调查他们和中国人的交流频率和方式、他们所遇到的困难、探讨为什么他们会遇到这类的困难，以及他们的应对方式。研究结果表明，大部分的尼日利亚学生缺乏留学目的国家的社会文化知识，他们在社会、教育和文化适应方面都存在问题，而这归因于缺少跨文化交际的...The advancement of globalization and development of the Sino-African frame work has increased migration of Nigerians students in search of foreign education to China,. On arrival, these students are faced with very many challenges and difficulties. Cultural differences and personal adjustment problems has affected the Nigerian students language acquisition and adjustment patterns, creating an urg...学位：汉语国际教育硕士院系专业：海外教育学院_汉语国际教育硕士学号：2652015115465