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The purpose of this paper is to design, build and test a low power high frequency (HF) transmitter that can be received by the Super Dual Auroral Radar Network (SuperDARN) radar installed at SANAE IV, the 4th South African National Antarctic Expedition Station. It is proposed that it may be possible to do propagation studies using the radar and the fixed frequency, ground-based HF transmitter beacon. Interpretation of the measurements can be used to study the ionosphere, especially Travelling Ionospheric Disturbances, which are signatures of atmospheric gravity waves.

In the absence of the actual deployment of the HF transmitter beacon in Antarctica, extensive simulations have been done to evaluate the expected performance of the transmitter in relation to the SuperDARN. A field trial has been executed between Hermanus (34.4241° S, 19.2247° E) and Pretoria (34.0558° S, 18.4589° E) in South Africa. In future, the beacon will be placed at the South Pole with its antenna radiating towards SANAE IV.

The HF transmitter conforms to the power and frequency stability requirements both during propagation tests conducted between Hermanus and Pretoria, as well as when the device was exposed to temperatures that ranged from +40°C to −45°C in a thermal chamber. Propagation in Antarctica is expected to differ from the field tests conducted due to the differences in density and dynamics of the polar ionosphere, compared to the mid-latitude ionosphere.

Space weather research, including forecasting atmospheric gravity waves and determining the expected electron density profile of the ionosphere, is of great scientific interest. The data received from the HF beacon can be used to study and characterize the ionosphere of the region between the South Pole and SANAE IV. Parameters of the ionosphere, such as electron density, geomagnetic storm effects, ionospheric motions and sky wave propagation paths will be better understood from analysing the signal received from this transmitter after it has been reflected and refracted by the ionosphere.

The cost of housing is very high in Yemen compared with Middle East countries, which has caused a shortage of housing supply, especially for the low‐income group. The purpose of this paper is to identify factors that are significantly influencing housing cost in Yemen.

The study surveyed 60 professionals in housing in Yemen, to identify factors influencing housing cost that are related to land, materials used, construction methods used, finishing works, and other factors/related issues. The questionnaire survey instrument consisted of 32 factors, which were grouped into these five categories. The level of importance was measured and the relative importance of weightage was ranked for all five categories.

This study found that cost of project land, cost of cement and steel for reinforced concrete are the most significant factors influencing housing cost in Yemen.

Based on the analysis of the ranking and intensity of housing cost factors, this paper further suggests possible improvements for decreasing the housing cost in Yemen. These recommendations are hoped to increase more regulated housing development and housing policy.

Evaluating housing projects is an essential task to determine the effectiveness of these projects and to provide a useful feedback to the projects’ initiators ‐ be it the public or the private sector. The evaluation could be on a number of different bases. Reports the results of research work aiming to compare the quality and effectiveness of three housing projects initiated by the Yemeni government in the capital ‐ Sana’a. The basis chosen for evaluating the public low‐income housing schemes is the housing quality measurement technique. This technique is used for measuring quality under widely different housing standards. It is a way of assessing the environmental quality and hence evaluating the success or failure of a particular housing project. Satisfaction of residents has also been evaluated and reported in an earlier paper (Al‐Abed and Mustapha, 1996).

The purpose of this paper is to present a procedure to estimate the total irrigation water requirement for a command area of 2,500 hectares in an arid environment under various crops and soil types using GIS for data storage, analysis and visualization of results.

Bani Al‐Harith agricultural area in Sana'a basin, Yemen was chosen for the study. ArcView GIS was used to plan for suitable crops and estimate the irrigation water requirements based on the farmer's preference and soil types. Using the available soil maps, the soil characteristics such as salinity, texture and suitable crop types were overlaid to produce the crop blocks map. The water balance equation was used to produce the crop water requirement map considering the crop coefficient for different crop stages. The total water demand for each irrigation block was calculated by summing the three components, namely percolation loss through the soil, maximum evapotranspiration of the crop and leaching requirement (LR) to maintain an acceptable salinity level.

The case study is an example of using GIS as an effective tool in irrigation planning. GIS facilities to acquire, store, analyze and display spatial data were used to produce the soil class map, soil profile map, crop map and water requirement map. The profile EC_e values for the chosen crops is within the crop salinity tolerance for 100 percent yield except for blocks 4 and 5 where grape and coffee respectively are suggested to be grown. The profile EC_e values are 18.37 dS/m in block 4 and 3.27 to 7.88 dS/m in block 5. The tolerance threshold of 100 percent yield for grape is 1.5 dS/m and for coffee is 3 to 6 dS/m. The salinity of the irrigation water was 2.08 dS/m. From the crop blocks map, the salinity tolerance level for 100 percent yield of onion for block 1 is 1.2 dS/m, tomato for block 2 is 2.5 dS/m, alfalfa for block 3 is 2 dS/m, grape for block 4 is 1.5/ dS/m, and the salinity tolerance level for 100 percent yield of coffee for block 5 is 5 dS/m. Leaching requirements were obtained by taking EC_w value of 2.08 and EC_e of 1.2, 2.5, 2, 1.5 and 5 for onion, tomato, alfalfa, grape and coffee respectively. The peak total water requirement occurred in May and was found to be 5,595 m³/ha, or 560 mm. The design irrigation water requirement for every block is shown in a map for easy visualization and manipulation to produce the best combination of soils, crops and water use.

This method of determining the total irrigation water requirement is dependent on the selected irrigation system and crops whether shallow‐rooted, deep‐rooted or tree crops. The use of water in agriculture should be judicious, precise and sustainable. Application of GIS can be a useful tool in irrigation management since it provides rapid access to underlying information of crop suitability. The designer can try out various combinations of crops, to suit the soils and available water.

This methodology is useful for training irrigation engineers and water resource planners on the use of GIS technique to plan irrigation projects in arid areas.

This technique has never been applied to the study area.

For the last 20 years, the Yemeni government has been providing housing schemes for low‐income groups. These low‐income housing schemes have not, however, been evaluated. Based on a post‐occupancy evaluation of three low‐income public housing schemes in Sana’a, Yemen, the paper describes the residents’ judgement and assessment of the environment in which they are living. Interviews with 180 occupants revealed that they attach great importance to the level of satisfaction with their neighbourhoods. The most important factor associated with neighbourhood satisfaction was privacy, a reflection of the cultural background in Yemeni society.

The purpose of this paper is to assess the TQM readiness level of Yemeni Organizations. In addition, this study compares the level of readiness between the various Yemeni organizations.

Based on the TQM literature, related and relevant information had been gathered to develop an assessment tool used in this research. The main content of the assessment focused on statements related to the most common TQM principles. Data were collected by an assessment team and analyzed using quantitative methods to answer the related research questions.

The analysis results showed some of the TQM principles were being practiced by Yemeni organizations, to some extent, and with variant levels. The most widely practiced principle was customer focus, and the lowest principle practiced was continuous improvement. Also, the data showed the level of TQM readiness in Yemeni organizations was 58.93 percent. This level of TQM readiness indicates there is a potential for successful adoption of quality management standards and models in Yemeni organizations.

This study extends previous limited research in TQM readiness level measurement. It also adds to the body of TQM knowledge within the context of Yemen. In addition, this study contributes to the understanding of TQM implementation in an least developed countries (LDC) environment, where LDC organizational culture has its particularities on implementing TQM.

This paper contributes to a better understanding of TQM in an LDC country, which is Yemen. The paper points out which of the TQM principles are important to potential adoption of quality management standards and models. This study could further expand research, regarding the TQM in Yemen.

The purpose of this paper is to identify the factors that cause housing shortage for low‐income groups in Yemen and recommend some solutions to alleviate the problem.

A questionnaire survey has been used as the tool to carry out this study. The first part of the questionnaire consisted of three groups namely: economic, administrative, and legal factors. The second part consists of suggestions on housing supply, construction methods, and materials used for low‐cost housing in Yemen. The level of importance of the categories was measured and the relative importance of weightage was ranked.

The results show that the most important economic factors causing housing shortage were poor handling of available economic resources and shortage of economic resources. The most important administrative factors causing housing shortage were lack of organization and synchronization and not conducting studies on housing. The most important legal factor causing housing shortage was lack of legalization of housing.

The findings could be used to improve housing policies and strategy in Yemen in order to decrease the housing shortage, particularly for the low‐income group.

The purpose of this paper is to deal with profit maximization problem of two-layer supply chain (SC) under fuzzy stochastic demand having finite mean and unknown variance. Buyback policy is employed from the retailer to supplier. The profit of the supplier solely depends on the order size of the retailers. However, the loss of shortage items is related to loss of profit and goodwill dependent. The authors develop the profit function separately for both the retailer and supplier, first, for a decentralized system and, second, joining them, the authors get a centralized system (CS) of decision making, in which one is giving more profit to both of them. The problem is solved analytically first, then the authors fuzzify the model and solve by fuzzy Hausdorff distance method.

The analytical models are formed for both centralized and decentralized systems under non-cooperative and cooperative environment with suitable constraints. A significant assumption on density function, namely Cauchy-type density function, is introduced for demand rate because of its wider range of the retailers’ satisfactions. Fuzzy Hausdorff metric is incorporated within the fuzzy components of the fuzzy sets itself. Using this method, the authors find out closure values of both centralized and decentralized policies, which is an essential part of any cooperative and non-cooperative two-layer SC models. Moreover, the authors take care of the profit values with corresponding ambiguities for both the systems explicitly.

It is found that the centralize policy of SC could only be able to maximize the profit of both the retailers and suppliers. All analytical results are illustrated numerically along with sensitivity analysis and side by side comparative studies between Hausdorff and Euclidean distance measure are done exclusively.

The main focus of attention of the proposed model is given to usefulness of Hausdorff distance. Unlike other distances, Hausdorff distance can take special care on the similarity measures of different fuzzy sets. Researchers have been engaged to use Hausdorff distance on the different fuzzy sets but, in this study, the authors have used it within the components of a same fuzzy set to gain more closure values than other methods.

The use of this Hausdorff distance approach is totally new as per literature survey suggested yet. However, the Cauchy-type density function has not been introduced anywhere in SC management problems by modern researchers still now. In crisp model, the sensitivity on goodwill measures really provides a special attention also.

Physician satisfaction (PHS) in the pharmaceutical business is a major issue that has created serious concerns for pharmaceutical companies and medical practitioners. The purpose of this paper is to explore the mediation effect of physician perceived value (PPV) on the relationship between marketing mix strategy (MMS) and PHS in the pharmaceutical industry in Yemen.

A non-probability purposive sample of 500 physicians was surveyed by using a self-administered questionnaire. Out of the 500 questionnaires, only 192 surveys were returned. Consequently, only 170 questionnaires were usable for the final analysis, with a 34 percent usable response rate. Several statistical techniques were performed including reliability, factor analysis, multiple regressions analysis, and hierarchical regressions to examine the mediation effect of the PPV.

The results showed that MMS elements, namely, product, price, promotion, and place, significantly contributed to PHS. The results also indicated that MMS elements, namely, price, place, and promotion, significantly contributed to PPV, whereas product showed an insignificant contribution. The PPV significantly contributed to PHS. Hierarchical regression results indicated that PPV partially mediated the relationship among MMS elements, namely, price, place, promotion, and PHS. Product variable was excluded in hierarchical analyses because the variable was insignificant to PPV.

This paper is the first to deal with perceived value as a mediating variable between elements of MMS (4Ps) for drug product and PHS in the context pharmaceutical business.

Maneno mengi yanayohusu haki za binadamu na haki za kiteknolojia hayajatafsiriwa katika lugha ya Kiswahili. Kwa hivyo, wataalamu wa teknolojia na watetezi wa haki za kidijitali hutumia maneno ya Kiingereza – hata bila utohozi – wanapozungumzia haki za kiteknolojia. Hali hii ya mambo inachangia udhoofu fulani katika utetezi wa haki za kidijitali kwani wanaojaribu kueleza jamii umuhimu wa haki hizi hulazimishwa kutegemea msamiati wa Kiingereza usiyo na msingi au viungo na lugha ya Kiswahili Katika makala hii, tutazungumzia umuhimu wa kukaribisha watu kutumia lugha za Kiafrika kwenye mtandao.

Kiswahili ni lugha ya Kiafrika inayozungumzwa katika eneo zaidi sana duniani. Karibu watu milioni mia moja na arobaini Afrika mashariki wanazungumza Kiswahili kama lugha yao ya kwanza au ya pili, miongoni mwao Wakenya na Watanzania, wenyeji wa nchi ambamo Kiswahili ni lugha ya kitaifa. Tena kuna historia ndefu ya kutumiwa kwa lugha ya Kiswahili katika uandishi, uchapishaji na ubunifu wa utamaduni wa kisasa. Kiswahili pekee yake ndiyo lugha ya asili ya Kiafrika inayotumika kama lugha ya maalum ya Umoja wa Mataifa za Kiafrika. Hata hivyo, kwa upande wa matumizi ya Kiswahili, hasa kwenye mada ya teknolojia, Kiswahili imewachwa nyuma.

Zaidi ya maneno rasmi, uwepo wa lugha za Kiafrika ni muhimu kuimarisha jumuiya za Kiafrika mtandaoni kwani lugha inalenga sana haki na utambulisho wa watu. Miradi za kutafsiri maneno za kiteknolojia katika lugha ya Kiswahili inahimiza jumuiya za Afrika Mashariki kuunda jamii inayosimamia matakwa yao vyema. Makala hii basi inazingatia umuhimu wa lugha kwenye kuunda jamii na katika hatua za kuondoa mbinu za kikoloni mtandaoni ili wenyeji wa Afrika Mashariki wajione mtandaoni kwa ujumla wao wote. Makala pia itazingatia semiotiki ya lugha katika ubunifu wa teknolojia, na umuhimu wa kutafsiri jamii ya lugha ya Kiswahili katika harakati za kuondoa ukoloni katika ubunifu huu. Lakini sio tu kwamba lugha ya Kiswahili ndio pekee inayoweza kuondoa mbinu za kikoloni mtandaoni, kwani pia lugha hiyo ina ishara za kutawalwa kwa jamii fulani. Bali makala hii inatumia mfano wa Kiswahili kuhimiza utumiaji wa lugha za kiasili au za kimama mtandaoni ili kulinda mustakabali wa kidijitali wa umma.

Umuhimu wa makala hii ni kuashiria jipya umuhimu wa lugha katika harakati za kuendeleza haki za kidijitali na hasa kuondoa mbinu za kikoloni kwenye teknolojia, swala lisilowahijadiliwa katika lugha ya Kiswahili.