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The results of trial experiments carried out with a computer simulation model of total reflection X‐ray fluorescence, TXRF system to determine optimum conditions for detecting certain elements of interest under various analytical conditions in a given ten‐element standard sample is presented in this paper. Results of these trial experiments show that the detectability of elements improved with increasing applied voltages up to about 43kV (for a Molybdenum anode TXRF spectrometer) and atomic number of elements. Variation of geometry such as the glancing incidence angle of the excitation beam reflected slight increase in minimum detection limit, MDL values as the angle of incidence is reduced from an optimum value of 1.6mradian to 1.0mradian. The nature of the sample support was observed to affect the detectability of the elements as good detection limits were obtained if gold is used as sample holder..

The Igbos of south-eastern region of Nigeria are known for their rich cultural heritage which permeates all their socioeconomic life. Sacrosanct among their social institution is their business practice which has outlived generations, but its impact is still felt not only in the south-eastern region but also in Nigeria as a whole. Igbo business practices have become integral to an average Igbo man's life, and it is the cornerstone on which their values are promoted. This is evidence in their desires to make wealth and be successful hence the adage ‘ego ji oru’ which means ‘money has the answer to projects’. Generally, Igbo culture and values are reflected in their business practices. The Igbos have a strategic model of attracting, retaining, transferring knowledge and developing talents. This unique model has contributed to the sustenance of Igbo businesses through manpower development and has also influenced their business performance over the years. The Igbos seek and develop talents in their area of business interest for continuity, performance and value creation. This chapter explores how talents are recruited to become apprentices and how knowledge is transferred to these apprentices by their Igbo master known as ‘oga’. Also, the effects of the recruitment process and the knowledge transfer mechanisms on business performance are evaluated. The chapter adopts a case study approach and sampled six small Igbo businesses in Ajah market, Lagos. The chapter revealed that the Igbos have indigenous strategies of recruiting and developing talents which influence the performance of their business. Informed recommendations were made for business in Africa at the end of the chapter.

Double rotor induction machine (DRIM) is a particular type of induction machine (IM) that has been introduced to improve the parameters of the conventional IM. The purpose of this study is to propose a dynamic model of the DRIM under saturated and unsaturated conditions by using the equations obtained in this paper. Also, skin and temperature effects are considered in this model.

First, the DRIM structure and its performance will be briefly reviewed. Then, to realize the DRIM model, the mathematical equations of the electrical and mechanical part of the DRIM will be presented by state equations in the q-d axis by using the Park transformation. In this paper, the magnetizing fluxes saturation is included in the DRIM model by considering the difference between the amplitudes of the unsaturated and saturated magnetizing fluxes. The skin and temperature effects are also considered in this model by correcting the rotor and stator resistances values during operation.

To evaluate the effects of the saturation and skin effects on DRIM performance and validate the model, the machine is simulated with/without consideration of saturation and skin effects by the proposed model. Then, the results, including torque, speed, stator and rotor currents, active and reactive power, efficiency, power factor and torque-speed characteristic, are compared. In addition, the performance of the DRIM has been investigated at different speed conditions and load variations. The proposed model is developed in Matlab/Simulink for the sake of validation.

This paper presents an understandable model of DRIM with and without saturation, which can be used to analyze the steady-state and transient behavior of the motor in different situations.

One of the major reasons for ineffective project delivery in the Nigerian construction industry is the improper assessment of risk factors. As a result, the industry continues to suffer poor performance with many projects failing to meet time and cost targets. This paper identifies the risk factors inherent in different building procurement methods and assesses their perceived relative importance with a view to evaluating their impact on project cost. The paper reports on a study carried out through a questionnaire survey of professionals within the construction industry in order to asses the relative importance placed on risk factors. Responses from the survey were analysed using relative importance index for the purpose of evaluating the impact of risk on projects cost. Data were collected on selected completed projects and analysed using frequencies, mean values and relative important index. The main risk factors identified are finance and political influence. A model was developed by relating the variation between the initial contract estimate and the actual project cost to the risk variables. From the analysis, the percentages of projects cost overrun due to the impact of risk were established for each procurement method investigated. The paper recommends that contingency additions should be based on the procurement method used.

Development runs on a continuum, having traditional, transitional and desired (relative) development stages. Rather than moving on, the continent of Africa has remained perpetually transitional due to its inability to strategically position itself globally, and its attendant international maneuvers; as well as its inability to break away from the anti‐development traits of the traditional stage of development and launch into the future. This, has invariably resulted in a ‘Departure‐Arrival’ (from one stage of development to another) crises, and distractions, confusions, and uncertainties, which now pervade the development terrain of Africa.

This chapter aims to highlight talent management approaches and succession planning principles deployed by traditional Igbo businesses in Nigeria. Insights came from interviews of a purposively selected sample of Igbo businesses drawn from different sectors of the Nigerian economy and different geopolitical zones of the country to give a national representation of the approaches they deploy in talent management and succession planning.

The chapter commences with a brief literature review of talent management and then proceeds to indicate the methodology deployed in data collection, analysis and presentation. The next section presents findings in detail on how Igbo businesses embark on talent management activities such as talent identification and attraction; interviewing; talent assessment; apprenticeships; training; risk considerations; compensation and rewards. Some training areas discussed in detail include nature of the sector, customer service, inventory management, supplier management and cash handling. The subsequent section highlights some challenges with talent management and approaches Igbo businesses adopted in overcoming them.

The chapter also provides some insights as cases of approaches traditional Igbo businesses adopted in succession planning – this gives more perspective on the contextual circumstances that inform the strategies the businesses adopted in talent management. The chapter concludes by discussing in general, succession planning approaches deployed by traditional Igbo businesses.

This chapter models industrial, tech, and financial cooperation between Russia and the countries of the Asia-Pacific region. We use several complex methods of economic and mathematical modeling to analyze specific features of such cooperation and determine critical factors in industrial, technological, and financial development. The preferable choice for the Asia-Pacific region is cooperation with Russia, which is ready for an increase in imports of industrial and high-tech products as well as joint industrial innovational entrepreneurship. Investments would lead to synergetic effects, ensuring simultaneous industrial, technological, and financial development.

Understanding the thermal performance of sandcrete hollow block walls in the tropic is very essential for occupants' well-being, productivity and efficiency, due to its widespread application in buildings in the study area. Lokoja, in Nigeria, lies in the warm humid zone with its attendant's high temperatures all year round. Thus, providing an acceptable walling material that will control the high indoor air temperature becomes imperative. This paper assessed sandcrete hollow blocks as a walling material used in Lokoja, to determine the thermal performances for effective thermal comfort of the residents.

It involves the construction of a habitable model building with the commonly available sandcrete hollow blocks in the area. One unit of Cryopak iMINI Temperature and Relative Humidity Data Logger called new generation intelligent iMINI with Serial Number and Product Code MX-CI-145–0009 and MX-HE-S-16-L was installed, to record the indoor air temperature and relative humidity data at an interval of one hour, for 12 months covering dry and wet seasons. The results of the recorded data were downloaded to an excel spread sheet for assessment and analysis throughout the seasons. The values were computed using the temperature–humidity index (THI) equation, with a view to determine the indoor thermal comfort level category.

The study revealed that sandcrete hollow block walls provide thermal discomfort of the indoor environment for both seasons, with attendant adverse effects in the comfort of the occupants. The paper concludes that proper orientation of buildings, planting of trees, use of low absorbing or reflective surface materials, application of cavity walls to receive insulation materials in between the hollow spaces provided, instead of the single walling as well as providing shading device elements, can improve users' comfort and also ameliorate the heat effect on the external surface of building transferred into the interior by conduction, radiation or convection within the area and in the tropics at large. Other thermally eco-friendly wall materials available in Lokoja includes timber, stabilized laterite–cement blocks, burnt bricks and earth-mud bricks which can be used to replace sandcrete hollow block walls. These alternative wall materials are used for construction of residential and office buildings by the colonial government of Sir Fredrick Lugard in the study area.

The application of sandcrete hollow blocks as a wall material is in vogue, not minding its thermal discomfort to the users and the environment; this is due to its availability and ease of production. The acceptability of this walling material requires holistic study to unravel the best way to reduce the thermal discomfort inherent in its application.

The author succeeded in revealing the thermal performance of sandcrete hollow blocks as walling material in Lokoja, the study area. It is a first attempt at understanding the performance for human comfort in the area. This will greatly assist the resident and other researchers to improve on the application of sandcrete hollow blocks as walling material towards ensuring that maximum indoor thermal comfort is achieved.

Improving hospital care for people with dementia is a well-established priority. There is limited research evidence to guide nursing staff in delivering person-centred care, particularly under conditions where patients are emotionally distressed. Misunderstood distress has negative implications for patient well-being and hospital resources. The purpose of this study is to use the expertise of nurses to recommend ways to care for the emotional well-being of patients with dementia that are achievable within the current hospital setting.

A qualitative study was conducted in two long-stay wards providing dementia care in a UK hospital. Nursing staff (n = 12) were asked about facilitators and barriers to providing emotion-focused care. Data were analysed using thematic analysis.

Nursing staff said that resources existed within the ward team, including ways to gather and present personal information about patients, share multidisciplinary and personal approaches, work around routine hospital tasks and agree an ethos of being connected with patients in their experience. Staff said these did not incur financial cost and did not depend upon staffing numbers but did take an emotional toll. Examples are given within each of these broader themes.

The outcome is a short-list of recommended staff actions that hospital staff say could improve the emotional well-being of people with dementia when in hospital. These support and develop previous research.

In this paper, frontline nurses describe ways to improve person-centred hospital care for people with dementia.

The stabilization of earthen blocks improves their mechanical strength and avoids adobe construction erosion due to rainwater. However, the stabilization affects the thermal properties of the earthen blocks, and thus their capacity to provide adequate thermal comfort to occupants. This article examines the influence of cement and geopolymer binders on thermal comfort in compressed earthen buildings in hot and arid climates.

The test cell is on the building platform in Burkina Faso. The building is made of compressed earth blocks (CEB) consisting of laterite, water and binder. The thermal models of the building were implemented in EnergyPlus v9.0.1 software. Empirical validation is used to check whether the model used for the thermal dynamic simulation can reproduce with accuracy the thermal behavior in a real situation. The adaptive thermal comfort model of ASHRAE 55–2010 was used to assess thermal comfort in long-term hot and dry tropical conditions.

The results show that the CEB buildings remain hot despite the use of cement or geopolymer binder. Indeed, with both cement and geopolymer binders, on a daily basis, 19 h and 15 h are uncomfortable during, respectively, the hot and cold seasons. An increase of 1% in cement content raises the comfort hours by 9.2 h during the hot season and 11.7 h during the cold season. Hence, the comfort time varies linearly with the cement content in the building material. Moreover, there is no linear relationship between comfort time and geopolymer rate.

Complementary work should also assess the influence of stabilization on building humidity levels. In fact, earthen materials are very sensitive to outdoor humidity and indoor humidity affects thermal comfort even if it is not taken into account in the ASHRAE adaptive thermal comfort model.

The present study will certainly contribute to a better valorization of clay potential in countries with similar climatic conditions.

The use of geopolymer binder is a suitable ecological option to replace the cement binder. It is important to mention that nighttime comfort can be increased through passive strategies such as natural ventilation.

Most CEB material stabilization analyses including cement and geopolymer ones were mostly investigated at the laboratory scale and less at the building scale. Also, the influence of the binder rate on the thermal performance of buildings made of cement and geopolymer has not yet been assessed. This paper fills this gap of knowledge by assessing the impact of cement and geopolymer binder rates on the thermal comfort of CEB dwellings.