Timetabling in constraint logic programming

In this paper we describe the timetabling problem and its solvability in a Constraint Logic Programming Language. A solution to the problem has been developed and implemented in ECLiPSe, since it deals with finite domains, it has well-defined interfaces between basic building blocks and supports good debugging facilities. The implemented timetable was based on the existing, currently used, timetables at the School of Informatics at out university. It integrates constraints concerning room and period availability

Status Quo Bias: Is it Human Habit to Prefer the Current Situation and Abhor Changes?

Status quo bias is a cognitive bias found in many fields including business, economics, political science, sociology, and psychology just to mention a few. It is a situation where people choose to do nothing or maintain current or previous decisions without a change. However, in today’s world, change is one among the things that are constant; thus, organizations and individuals need to develop the capability to change so as to capitalize on new opportunities that emerge from changes. The study in this paper has used content analysis to arrive to its findings which were obtained from books, peer review journals, reports and Internet information sources. The research question to be examined is whether the preference of status quo bias is a human nature or the laziness of human consciousness on making sound decisions. Findings show that status quo bias, though preferred most does not help rational decision making when individuals choose among alternatives. Thus, in order to make rational and informed decisions, individuals shouldn’t have a bias towards sticking to the old but should show some characteristics that advance positive changes. Keywords: Status quo bias, Changes, Rational decision making

Discourse patterns of lessons on topics perceived to be difficult in biology in selected secondary schools of Luapula province, Zambia.

Thesis of Doctor of Philosophy in Science Education.This study explored classroom discourse patterns of perceived difficult topics in biology such as classification of living organisms, mitosis and meiosis at senior secondary level in selected secondary schools of Luapula Province in Zambia. A collective case study design was used and data was obtained from students and teachers, using observation schedules and interview guides. Purposive sampling was used to select the sample of schools from the target population of Luapula Province of Zambia. Data collected was analysed using discourse analysis and thematic analysis. The study found out that three discourse patterns were used during lessons on topics perceived to be difficult. These three discourse patterns are: Pupil to pupil discourse pattern, teacher- led discourse pattern and teacher-explanation discourse pattern. The choice of discourse patterns by teachers hinged on the following: non availability of teaching and learning aids, desire to cover more content, need to relate lessons to real life situations, nature of the topic to be taught, skill in managing groups, classroom environment and pupil participation. The effects were two fold; lack of understanding and enhanced understanding of stages of cell division and biological names of living organisms. The observed causes of lack of understanding included the following: Experiments on cell division were not conducted because they usually took a lot of time to be concluded. Classification was not taught practically as a result pupils connected classification with the task of memorising a list of biological names. Most teachers used inappropriate group activities and allocated inadequate time to cell division and classification of living organisms as these topics were taught around examination time. Furthermore, the study revealed that many teachers of biology taught perceived difficult topics in biology by following prescribed Zambian textbooks instead of the syllabus. This made them leave out important aspects of the syllabus and taught kingdoms and phyla not found in the syllabus. Among the causes of enhanced understanding, were mind capturing introductions, properly organised group work, clear explanations from the teacher and all inclusive questioning techniques by the teachers. Some of the recommendations made by the researcher were that: Teachers should combine the three discourse patterns namely; teacher-explanation, teacher-led and pupil to pupil discourse patterns when teaching biology because these patterns proved effective when used together during the lesson observations. Teachers should avoid using one discourse pattern during lessons on topics perceived to be difficult because it is monotonous and does not usually bring about effective learning. Workshops and seminars should be organised internally by schools for teachers to enable them acquire skills of teacher-explanation, teacher-led and pupil to pupil discourse patterns for teaching biology. Biological terms must be explained to pupils in a clear way by using the teacher-explanation discourse pattern so that pupils can understand them clearly. Pupils should be encouraged to draw diagrams on cell division during pupil to pupil discourse pattern in order for them to understand stages of cell division. Teachers must use real life examples of living organisms to help classify them into different kingdoms, phyla/divisions, classes, orders, families, genus and species during the teacher led discourse pattern

Learning difficulties grade 12 Pupils experience in Biology: The case of selected High School in Samfya District of Zambia

Although the general view is that biology is the easiest science subject to learn, examination results have shown that many pupils fail biology at end of grade 12. The purpose of the study was therefore to investigate the nature and causes of learning difficulties pupils experience in biology in high schools of Samfya district. This study was guided by the following questions: 1.What learning difficulties do pupils experience in high school biology? 2.Why do pupils experience these learning difficulties? 3. How can these learning difficulties be minimized?A descriptive survey design was used and data were obtained from eighty grade 12 pupils and ten biology teachers using Interview Schedules and Self completion questionnaires. Simple random sampling was used to select the sample from the target population. Data collected were analysed using the content analysis approach. The study found that pupils experienced difficulties in the following aspects such as biological terms, biological diagrams, plotting and interpreting graphs, calculations involving magnification and practical activities.Factors identified to have caused learning difficulties in biology included; non-availability of some reagents to be used in practical lessons, poor English back ground by some pupils, failure by teachers to explain clearly to pupils biological concepts, belief by some pupils that biology was difficult to learn, lack of appropriate learning aids and inadequate time allocated to the wide biology syllabus. It was recommended among others that chemicals for various practical activities be bought by schools in adequate amounts so that teachers can use them during lessons and that pupils be given assignments involving both drawings and written tasks. Biology teachers should teach learners the various meanings and interpretations of words and phrases that occur in the biology vocabulary. Teacher training institutions must prepare biology teachers effectively. Adequate time must be allocated to the teaching of biology. There is need to review the biology syllabus and reduce the content so that more time is given to experimental work

Promoting Youth Empowerment through Business Mentorship in South Africa

One of the setbacks in youth entrepreneurship is the unavailability of proper business knowledge and mentorship. In rural municipalities of South Africa, the absence of youth mentorship has widened the inequality gap and triggered deep youth poverty. This article reinforces the importance of youth mentoring in crucial business aspects such as writing business plans for entrepreneurial success. This study is premised on a positivist paradigm that uses a quantitative research design. The researchers administered twenty questionnaires to youth entrepreneurs in Buffalo City Metropolitan Municipality (BCMM) in the Eastern Cape Province of South Africa to examine whether mentoring the writing of business plans plays an essential role in their entrepreneurial ventures. The results for this article reveal that most youth entrepreneurs do not receive mentoring to boost their entrepreneurial ventures, even though mentoring has been identified as necessary.  The report recommends that youth entrepreneurs be mentored to promote their businesses, which will create youth economic development and employment creation in BCMM

Essays on monetary integration in Southern Africa

Following the successful introduction of the euro in Western Europe, several regional economic blocs in Africa are planning to launch a common currency as an intermediary step towards the emergence of a single currency for the entire continent. The purpose of this dissertation is to tackle several economic issues related to monetary integration and empirically apply it to the context of the Southern Africa Development Community (SADC). In the first essay, we estimate trade potentials for southern African countries using the gravity model approach. More specifically, we use the level of infra-regional trade as predicted by the gravity model and compared it with the observed trade in order to assess the trade potentials in the region, as well as the South Africa's trade potentials with its SADC partners. Our results demonstrate that the observed trade flows among SADC countries are largely greater than the ones predicted by the empirical model. We also found that other SADC member countries over-trade with respect to South Africa. However, there are still some unexploited trade potentials for several pairs of SADC countries. The second essay deals with the issue of the choice for the optimal nominal currency anchor to which the national currencies of the region have to be pegged to. Using a panel of 63 countries, we obtained OCA indices à la Bayoumi and Eichengreen for SADC countries vis-à-vis five potential nominal anchor currencies, and we find that the optimal nominal currency anchor for these countries is the US dollar. We also find several pairs of SADC countries which are suitable for a common currency on the basis of the estimated OCA indices. In the last essay, we empirically assess the expandability of the CMA within the SADC by investigating the convergence of monetary policies of each SADC member to that of South Africa, a proxy for CMA. Empirical tests show evidence of long-run relationship between South Africa and two countries, namely Botswana and Mauritius suggesting that these countries may able to follow the leadership of the South African Reserve Bank. Following the results of the Granger-causality test, the leadership hypothesis in the strict sense is rejected for the case of Mauritius and Botswana. However, the only other country which shows evidence of following the South Africa's leadership in terms of Granger-causality is Malawi. [PUBLICATION ABSTRACT

An assessment of the need for a monitoring model for public service training facilitators :|bthe case of a training agency at an Eastern Cape university

The purpose of this study was to assess the needs of a mentoring model for public service Training Facilitators. The study followed a qualitative interpretive research design whereby semi-structured interviews were used to gain answers from the three constructs addressing the research questions. The results of an assessment that was conducted by the researcher in this study indicate that there is a lack of a mentoring programme for FHS Training Facilitators and that the development of competencies and skills for Training Facilitators through mentoring is non-existent. It was through the findings that the need of mentoring was envisaged, leading to the creation of a comprehensive mentoring model for Leadership Development training. Findings relating to questions regarding the purpose of mentoring, knowledge of presenting training programmes on Leadership Development and requisite competencies and professionalism of Training Facilitators indicate that there is need for a mentoring programme for Leadership Development training at FHS. This study is therefore significant in that a mentoring model has been developed. The study is a new line of inquiry and will make an original contribution to literature on mentoring, proactive training methods and Leadership Development. There is little known on proactive training methods for Millenials on Leadership Development both in South Africa and internationally. This study had a bias towards the qualitative approach. It was conducted in the Eastern Cape Province. For this research, respondents were only Training Facilitators at FHS. The empirical study was limited to male or female Training Facilitators working for FHS and Training Facilitators who have worked for FHS for at least more than a year. The Management of FHS and administration staff members were excluded from the study since the study included only Training Facilitators from the Human Capital Training and Development Unit at FHS. The main focus of the study is mentoring, and does not include related aspects, such as career coaching, executive coaching, action learning and learnerships

Acute toxicity of produced water on selected organisms in the aquatic environment of the niger delta

The discharge of produced water (PW) and drill cuttings from oil operations may elicit varied toxicity in fresh, brackish and marine organisms when exposed. The Niger Delta re- gion which is the oil and gas province of Nigeria have incessantly been recipients of pro- duced water. The study was aimed at investigating the toxic effects of produced water on freshwater fish- Oreochromis niloticus and brackish water shrimp- Palaemonetes africanus in the Niger Delta region of Nigeria. Probit toxicity tests were conducted on the organ- isms through a 96 h bioassay using produced water (PW) obtained from Mobil, Qua Iboe Terminal (QIT) in Eket, Akwa Ibom State, Nigeria. The organisms were tested in separate tanks containing produced water of 0.0, 100, 200, 400, 800 and 1000 mL, mixed with 2 L of habitat water (fresh/ brackish water). The physicochemical properties of the mixtures were determined by multiparameter hand held probe and atomic absorption photometer (AAS). The physico-chemical parameters, particularly the pH, and conductivity of the PW at 26.5 °C were significantly higher ( p < 0.05) than those of the freshwater and brackish water samples. O. niloticus at the end of the 96 h test were 35%, 45%, 60%, 70% and 85%; while P. africanus had percentage mortalities of 25%, 35%, 45%, 60% and 80% at produced water (PW) of 5%, 10%, 20%, 40% and 50% respectively. Mortality rates of both test organ- isms being directly proportional to the percentages of PW and zero mortality recorded in the controls suggest that PW inflicted significant acute toxicity on the tested species. Higher mortality rates recorded in O. niloticus than P. africanus could be attributed to the increase of salinity following the introduction of the PW in the fresh water test media. The concentrations of PW administered in the study which were below the LC 50 were are 49,500 and 99,0 0 0 ppm, while 198,0 0 0, 396,0 0 0, and 495,0 0 0 ppm were above the LC 50. Results showed that the PW collected from the Mobil QIT effluent point source was toxic to the aquatic organisms, particularly the freshwater Oreochromis niloticus . We therefore speculate that 99,0 0 0 ppm of PW may be considered as the “no observed effect concentration”(NOEC)

Food mechanical properties and isotopic signatures in forest versus savannah dwelling eastern chimpanzees

Chimpanzees are traditionally described as ripe fruit specialists with large incisors but relatively small postcanine teeth, adhering to a somewhat narrow dietary niche. Field observations and isotopic analyses suggest that environmental conditions greatly affect habitat resource utilization by chimpanzee populations. Here we combine measures of dietary mechanics with stable isotope signatures from eastern chimpanzees living in tropical forest (Ngogo, Uganda) and savannah woodland (Issa Valley, Tanzania). We show that foods at Issa can present a considerable mechanical challenge, most saliently in the external tissues of savannah woodland plants compared to their tropical forest equivalents. This pattern is concurrent with different isotopic signatures between sites. These findings demonstrate that chimpanzee foods in some habitats are mechanically more demanding than previously thought, elucidating the broader evolutionary constraints acting on chimpanzee dental morphology. Similarly, these data can help clarify the dietary mechanical landscape of extinct hominins often overlooked by broad C3/C4 isotopic categories

Comparative evaluation of the Ifakara tent trap-B, the standardized resting boxes and the human landing catch for sampling malaria vectors and other mosquitoes in urban Dar es Salaam, Tanzania

BACKGROUND\ud \ud Frequent, sensitive and accurate sampling of Anopheles mosquitoes is a prerequisite for effective management of malaria vector control programmes. The most reliable existing means to measure mosquito density is the human landing catch (HLC). However, the HLC technique raises major ethical concerns because of the necessity to expose humans to vectors of malaria and a variety of other pathogens. Furthermore, it is a very arduous undertaking that requires intense supervision, which is severely limiting in terms of affordability and sustainability.\ud \ud METHODS\ud \ud A community-based, mosquito sampling protocol, using the Ifakara tent trap-B (ITT-B) and standardized resting boxes (SRB), was developed and evaluated in terms of the number and sample composition of mosquitoes caught by each, compared to rigorously controlled HLC. Mosquitoes were collected once and three times every week by the HLC and the alternative methods, respectively, in the same time and location.\ud \ud RESULTS\ud \ud Overall, the three traps caught 44,848 mosquitoes. The ITT-B, HLC and SRB caught 168, 143 and 46 Anopheles gambiae s.l. as well as 26,315, 13,258 and 4,791 Culex species respectively. The ITT-B was three- and five-times cheaper than the HLC per mosquito caught for An. gambiae and Cx. Species, respectively. Significant correlations between the numbers caught by HLC and ITT-B were observed for both An. gambiae s.l. (P < 0.001) and Cx. species (P = 0.003). Correlation between the catches with HLC and SRB were observed for Cx. species (P < 0.001) but not An. gambiae s.l. (P = 0.195), presumably because of the low density of the latter. Neither ITT-B nor SRB exhibited any obvious density dependence for sampling the two species.\ud \ud CONCLUSION\ud \ud SRBs exhibited poor sensitivity for both mosquito taxa and are not recommended in this setting. However, this protocol is affordable and effective for routine use of the ITT-B under programmatic conditions. Nevertheless, it is recommended that the trap and the protocol be evaluated further at full programmatic scales to establish effectiveness under fully representative conditions of routine practice