To provide high service level, an organisation must maintain flexibility in production planning. This allows them to react to changes in demand and supply information. Changes in production plan decreases planning stability. Low stability has knock on effect on supply of material. This causes disruptions in production and delivery as well as increased cost due to higher inventory cost, stockout costs, expediting cost and sub optimal setups cost. This study aims to determine the methods to improve planning stability. The factors that influence stability like planning horizon, safety stock, inventory policies are examined in detail in a real world setting. Literature review of existing work on planning stability was carried out. Single case study was used to study this phenomenon in depth at a pharmaceutical manufacturing company. Qualitative data regarding planning method, flow of information, interaction between departments, time horizons were studied. Quantitative data includes the production plans across different planning cycles. Existing stability levels were computed to determine the future levels of stability required. The literature was compared with existing working methods to find improvements. Plans away from the frozen period will have low stability due to forecast volatility. But as we move closer to frozen period, higher stability should be achieved. Low planning horizon in the immediate periods are due to material supply uncertainty which can be prevented by having responsible suppliers and increasing safety stocks. Using a stabilisation parameter can prevent rescheduling when small changes in demand occurs. This ensures unnecessary reaction to small changes are prevented.  Increasing the planning horizon will provide suppliers with accurate information regarding quantity and timing which will in turn help them plan better. Lastly, safety capacity in production can help towards handling unexpected production loses and thereby prevent re-planning.

The present study provides a systematic overview of the most important software requirement prioritization techniques. Software requirement prioritization is a process in software engineering that precludes the actual development of software application programs and deals with assigning priorities to single requirements to define the order of their implementation. The study aims to help researchers and practitioners in deciding about the right technique since each has its advantages and limitations. Compared to the existing reviews, the current one not only captures the most promising techniques but the more general trends behind them. The study utilizes the review protocol method that aims to answer four research questions about the most popular techniques, their taxonomy, their limitations, and involved processes. The empirical data was collected from six databases for scientific manuscripts and put under scrutiny to identify the most relevant and elaborated papers. The results from 53 selected manuscripts and 106 discovered techniques demonstrate that there is evidence of a gradual shift from purely manual elicitation methods to computed-assisted and/or algorithmic ones.

Breastfeeding is at its best when both the mother and infant benefit from the experience. Aim: To obtain data on the adequacy of the diet and nutrition knowledge of lactating women (0-6 months postpartum) living in a low socio-economic area in Nairobi. The findings could be used to plan future nutrition intervention programs. Research design: A cross-sectional survey in the quantitative and qualitative research paradigms. Health status indicators, socio-economic and cultural factors were additionally investigated as interactive factors that could influence the nutrient intake and nutrition knowledge of the lactating women. Setting: Mbagathi District Hospital, located at the edge of Kibera slum area in Nairobi. Sample: Lactating mothers (0-6 months postpartum), who were visiting the Maternal-Child Health Clinic to bring their children for immunisation, were recruited. Convenience sampling was used (N=120). Informed consent was obtained from the mothers in their home tongue. Methodology: Individual interviews in Swahili, using structured questionnaires (Socio biodemographic questionnaire, Hunger Scale, 24 Hour-recall, and Quantitative Food Frequency Questionnaire), and anthropometry (according to standard procedure) were done in the quantitative domain. Seven structured focus group discussions were employed in the qualitative domain. Descriptive and inferential statistics were used on the quantitative data, and Krueger‘s framework of analysis on the qualitative data. Ethical approval was obtained from the Ethics Committee, Faculty of Natural and Agricultural Sciences, University of Pretoria; Ref no EC 080922-039, and research permission was granted by the National Council for Science and Technology, Nairobi; Permit no NCST/5/002/R/355. Main findings: Majority of women (92%) had energy intakes between 5040 – 10080 kJ/day with the mean energy intake of 6975.5 kJ/day which was lower than the recommended 11340 kJ/day. Macronutrient intake was within the acceptable macronutrient distribution ranges, whereas the micronutrients were consumed below the recommended dietary allowances (WHO). The mean adequacy ratio (excluding niacin) was 0.74. The highest frequency of consumption (100%) was from cereals, while the lowest were for vitamin A rich vegetables/fruits (6.6%) and dairy products (1.7%). Overall, the mean Food Variety Score (FVS) was 6.6 ( ± 2.0) and the Dietary Diversity Score (DDS) was 4.3 ( ± 1.0). Hunger assessment revealed 43 households that were food secure, whereas 77 households were either hungry or at risk of hunger. Majority of women (93%) had good nutrition knowledge but the rationale for applying the knowledge was lacking for most of the nutrition concepts. Socio-economic status, cultural beliefs and practices, health status and nutrition knowledge were all identified as probable factors that influenced the dietary intake of the lactating women. Recommendation: There seems to be a need for well-designed nutrition intervention programs focusing on nutrient intake from culturally acceptable and affordable foods to increase dietary diversity and food variety of lactating women in this low socio-economic area. With a concurrent increase in nutrition knowledge such interventions would improve their nutritional status. / Dissertation (MSc)--University of Pretoria, 2010. / Food Science / unrestricted

The odds ratio is one of the most widely used measures of association for 2 × 2 tables. A generalized Yule coefficient transforms the odds ratio into a correlation-like scale with a range from -1 to 1. Yule's Y, Yule's Q, Digby's H, and a new coefficient are special cases of a generalized Yule coefficient. The new coefficient is shown to be similar in value to the phi coefficient. A confidence interval and sample size formula for a generalized Yule coefficient are proposed. The proposed confidence interval is shown to perform much better than the Wald intervals that are implemented in statistical packages.

The tetrachoric correlation describes the linear relation between two continuous variables that have each been measured on a dichotomous scale. The treatment of the point estimate, standard error, interval estimate, and sample size requirement for the tetrachoric correlation is cursory and incomplete in modern psychometric and behavioral statistics texts. A new and simple method of accurately approximating the tetrachoric correlation is introduced. The tetrachoric approximation is then used to derive a simple standard error, confidence interval, and sample size planning formula. The new confidence interval is shown to perform far better than the confidence interval computed by SAS. A method to improve the SAS confidence interval is proposed. All of the new results are computationally simple and are ideally suited for textbook and classroom presentations.

Context and Motivation: Technology play a vital role in the people’s present life. These technology has different types of softwares and devices. Now a days people mostly live around the digital devices and involve with them. These softwares when using causes digital distraction. Mostly digital distraction occurs only when using digital devices. For the development of software and devices requirements play a major role in the development in an organization. Question/Problem: The requirements are developed into the features of software. These features when using can cause distraction. So to manage these digital distraction causing by the software, we considered requirements engineering, by introducing the requirements engineering process at the beginning of the development of software, so to develop a distraction-free software. This can be helpful for the developers to develop the distraction-free software from early stages for the user. Principal Ideas/Objectives: Our thesis mainly focus on the identification of quality factors requirements contributing to the digital distraction and analyse them and we also tried to identify feature usage and user experience of software to identify distraction of software and a mind-map is designed for the study of digital distraction. So that these can provide useful information for future studies. Methods/Contributions: In our thesis study, we conducted Systematic Literature Review using snowballing process for the identification of the literature about the digital distraction and analysed the SLR. Further an online survey is conducted on Instagram users to extract distraction features and reasons for distraction and then we used this data to plan a mind-map of different categories contributing to digital distraction. Results: The main findings and observations in our research are observed through SLR and survey results. For research question 1, the data that is extracted through SLR gives quality factor requirements that contribute to the digital distraction. An understanding of digital distraction among software and feature and also the causes are observed. For the research question 2, the data from the survey is collected from the users of Instagram are observed. The results from the survey are extracted to know about the distraction of software using the feature usage which is extracted from the survey and also the user experience. From these results of SLR and survey data, a mind map is designed to know about the study of the digital distraction. Conclusions: Finally, we come up with a idea by planning mind-map that helps the software developers and requirement engineers to build a distraction-free software. The results of this study can be helpful to all the software developers and also to the ones who want to carry our the research on requirements connection with digital distraction, this can be a start point for them.

Background: With the increasing number of software users using social media forums, providing feedback about the OSS projects, the developer’s need to address this feedback to understand the requirements of an OSS project. As different tools support different structures for the feedback, the need to classify, prioritize and filter them into a fundamental set of categories persists. Some of the feedback includes images from users, along with the text. These images may vary from a screenshot of the bug, encountered by the user to a code snippet modification as required by the user. The significance of how these images help the developers in fixing the bug is not clear. Objectives: This thesis aims to identify the underlying advantages of using images in the feedback or bug report submitted by the user for an OSS project to the developers. The goal is to find the extent to which different image attributes help the developer’s in understanding the issue suggested in the feedback or bug report. The research also aims to classify the view of practitioners regarding which image attributes affect the most and to propose a simple DSS model that can possibly be used by users and developers while attaching images in the feedback or bug reports. Methods: In this research, we have conducted an empirical study using systematic mapping and a survey study. We identified 28 research articles form systematic mapping using a search string and snowballing process to extract different image attributes. To triangulate and verify the results of the systematic map, we have conducted an online questionnaire replied by 32 respondents experienced in contributing to the OSS community. The usability of the image attributes has been evaluated from the responses received. Both quantitative and descriptive statistical analysis techniques were used to analyze the results. Results: From the 28 research articles identified for the systematic mapping study, we have extracted 11 image attributes that influence the developers in interpreting the software requirements from the images attached to feedback or bug reports. Of the identified image attributes, image quality and image resolution are considered to be the most useful attributes by the survey respondents. Moreover, two new image attributes (timestamp and steps to reproduce) are reported from the survey study. Conclusions: The identification and validation of the image attributes suggest the potential use of images in feedback and bug reports. Furthermore, these image attributes provide additional information to the developers in understanding the software requirements from the users perspective clearly. We propose a simple DSS model that can be used by the users and the developers before attaching an image along with the feedback or the bug reports to the developing OSS communities to promote further usage of images in feedback and bug reports for OSS.

Two methods of determining resource requirements at an Air Force maintenance depot were developed. The first method is designed for new workloads and is based on infinite queuing theory formulas. Tables have been developed for this method. The second method is designed for workload with, at minimum, several months of historical data. An optimum fit test was designed to aid in fitting and smoothing the empirical data to the normal distribution. These data are then input to simulation model for determination of resource requirements. (86 pages)

There are a number of factors that influence crop yield, two of which are soil moisture and fertility.

In the semi-arid west, moisture is often the limiting factor in plant growth. High crop production is dependent upon rainfall and supplemental moisture supplied through irrigation. Plants for these areas, which are most efficient in use of water, other things being equal, would be more desirable.