Search results for: power generation

Authors: Hossam Shalabi, George Hadjisophocleous

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The Canadian Nuclear Power Plants (NPPs) use some portions of NUREG/CR-6850 in carrying out Fire Probabilistic Risk Assessment (PRA). An assessment for the applicability of NUREG/CR-6850 to CANDU reactors was performed and a CANDU Fire PRA was introduced. There are 19 operating CANDU reactors in Canada at five sites (Bruce A, Bruce B, Darlington, Pickering and Point Lepreau). A fire load density survey was done for all Fire Safe Shutdown Analysis (FSSA) fire zones in all CANDU sites in Canada. National Fire Protection Association (NFPA) Standard 557 proposes that a fire load survey must be conducted by either the weighing method or the inventory method or a combination of both. The combination method results in the most accurate values for fire loads. An updated CANDU Fire PRA model is demonstrated in this paper that includes the fuel survey in all Canadian CANDU stations. A qualitative screening step for the CANDU fire PRA is illustrated in this paper to include any fire events that can damage any part of the emergency power supply in addition to FSSA cables.

Keywords: fire safety, CANDU, nuclear, fuel densities, FDS, qualitative analysis, fire probabilistic risk assessment

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Authors: Lakdar Sadi-Haddad

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The past few years study of very high speed electrical drives have seen a resurgence of interest. An inventory of the number of scientific papers and patents dealing with the subject makes it relevant. In fact democratization of magnetic bearing technology is at the origin of recent developments in high speed applications. These machines have as main advantage a much higher power density than the state of the art. Nevertheless particular attention should be paid to the design of the inverter as well as control and command. Surface mounted permanent magnet synchronous machine is the most appropriate technology to address high speed issues. However, it has the drawback of using a carbon sleeve to contain magnets that could tear because of the centrifugal forces generated in rotor periphery. Carbon fiber is well known for its mechanical properties but it has poor heat conduction. It results in a very bad evacuation of eddy current losses induce in the magnets by time and space stator harmonics. The three-phase inverter is the main harmonic source causing eddy currents in the magnets. In high speed applications such harmonics are harmful because on the one hand the characteristic impedance is very low and on the other hand the ratio between the switching frequency and that of the fundamental is much lower than that of the state of the art. To minimize the impact of these harmonics a first lever is to use strategy of modulation producing low harmonic distortion while the second is to introduce a sinus filter between the inverter and the machine to smooth voltage and current waveforms applied to the machine. Nevertheless, in very high speed machine the interaction of the processes mentioned above may introduce particular harmonics that can irreversibly damage the system: harmonics at the resonant frequency, harmonics at the shaft mode frequency, subharmonics etc. Some studies address these issues but treat these phenomena with separate solutions (specific strategy of modulation, active damping methods ...). The purpose of this paper is to present a complete new active harmonic compensation algorithm based on an improvement of the standard vector control as a global solution to all these issues. This presentation will be based on a complete theoretical analysis of the processes leading to the generation of such undesired harmonics. Then a state of the art of available solutions will be provided before developing the content of a new active harmonic compensation algorithm. The study will be completed by a validation study using simulations and practical case on a high speed machine.

Keywords: active harmonic compensation, eddy current losses, high speed machine

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Authors: Ana Mouro, Ana Ramalheira

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Since 1989, with the Fall of the Berlin Wall, Germany has undergone a profound restructuring political and economic process. When the Euro Crisis broke out, Germany was no longer the “sick man” of Europe. Instead, it had recovered its dominance as the strongest and wealthiest economy within the European Union. With the European Debt Crisis, that has been taking place in the European Union since the end of 2009, Germany´s Chancellor Angela Merkel has gained the power of deciding, so to say, on the fate of the debtor nations, but she neither stands for binding German commitments, nor refuses assistance. A debate on whether Merkel’s hesitation has been deliberated and used as a means of coercion has arisen on international print media, and the Portuguese Press has been no exception. This study, which was conducted by using news reporting, opinion articles, interviews and editorials, published in the Portuguese weekly Expresso and the daily Público, from 2008 to 2015, tries to show how Merkel’s hesitation, depicted in the press by the term “Merkiavelli”, was perceived in Portugal, a country that had to embrace the austerity measures, imposed by the European Central Bank, but defined under Angela Merkel´s leading role.

Keywords: Euro crisis, “Merkiavelli”, cultural studies, Portuguese quality press

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Authors: Zhao Xinlei

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In general, interstate relations are diverse and include economic, political, military, and diplomatic. Therefore, by analyzing the development of the relationship between Malaysia and China, we can better verify how the Hirschman effect works between small countries and great powers. This paper mainly adopts qualitative research methods and uses Malaysia's 2020-2022 political crisis as a specific case to verify the practice of the Hirschman effect between small and large countries. In particular, the interest groups in small countries that are closely related to trade with extraordinary abilities, as the primary beneficiaries in the development of trade between the two countries, although they may use their resources to a certain extent to influence the decisions of small countries towards great powers, they do not fundamentally determine the small countries' response to large countries. In this process, the relative power asymmetry between states plays a dominant role, as small states lack trust and suspicion in political diplomacy towards large states based on the perception of threat arising from the relative power asymmetry. When developing bilateral relations with large countries, small states seek practical cooperation to promote economic and trade development but become more cautious in their political ties to avoid being caught in power struggles between large states or being controlled by them. The case of Malaysia-China relations also illustrates that despite the ongoing political crisis in Malaysia, which saw the country go through the transition from (Perikatan Nasional) PN to (Barisan Nasional) BN, different governments have maintained a pragmatic and proactive economic policy towards China to reduce suspicion and mistrust between the two countries in political and diplomatic affairs, thereby enhancing cooperation and interactions between the two countries. At the same time, the Malaysian government is developing multi-dimensional foreign relations and actively participating in multilateral, regional organizations and platforms, such as those organized by the United States, to maintain a relative balance in the influence of the US and China on Malaysia.

Keywords: Hirschman effect, interest groups, Malaysia, China, bilateral relations

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Authors: Anum Obaid, Iman Fatima, Wanisha Feroz, Haleema Imran, Hammad Tariq

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Unmarried women over thirty years of age as a health issue is a relatively young phenomenon, but it is rapidly growing in Pakistan; therefore, it is a public health issue. The challenges affecting nutrition and public health are some of the indispensable components that need to be met to achieve sustainable development goals (SDGs). This research intends to explain these goals in the context of nutrition and public health, especially analyzing the issues related to unmarried women above the age of thirty in Faisalabad, Pakistan. Still, this research is not feasible in Pakistan. In Pakistan alone, 10 million women over the age of 35 are unmarried, based on a recent United Nations report. The United Nations, in cooperation with the World Health Organization, has identified health as a state of being healthy, free from illness or disease, and not just a condition where there are no diseases or bodily disabilities. The current generation of women is unmarried and living a life under constant pressure from society to deliver changes like the diet these women take, and hence, their nutritional status defines their comprehensive health triangle, a mix of physical, mental, and social well-being. The research was carried out under the qualitative research paradigm, specifically through interviews with the participants who were unmarried women and married women above the age of thirty. This qualitative study explores how marriage affects the intake of nutrients, nutritional health, psychological and social well-being and their effects. The realization of well-being consisted of factors like physical health, mental and emotional health, pressure from society, social health, economic independence, and decision-making power to reveal the impact of singleness on well-being. The findings disclosed that marital status had a notable impact on the diet habits and nutritional behaviors of women in Faisalabad. Also, it was found that single women suffer from more stress and are not as positive as married women because they are lonely, as their husbands are absent from their lives. The findings established that nutritional understanding is differentially affected by marital status as a determinant of the health triangle consisting of physical, mental, and social health. Awareness of these factors is significant in designing specific goal-directed interventions that can enhance the nutritional well-being and general health status of unmarried women in Faisalabad. Hence, this study underscores the necessity of maintaining supportive environments and increasing the regard concerning the health state of single ladies beyond thirty.

Keywords: health triangle, over thirty, singleness, age barriers, unmarried women, women’s health, well-being

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Authors: Meng Koon Lee, Mohammad Hosseini Fouladi, Satesh Narayana Namasivayam

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Research is focused on the response of soundboards of Classical guitars at frequencies up to 5 kHz as the soundboard is a major contributor to acoustic radiation at high frequencies when compared to the bridge and sound hole. A thin rectangular plate of variable thickness that is simply-supported on all sides is used as an analytical model of the research. This model is used to study the response of the guitar soundboard as the latter can be considered as a modified form of a rectangular plate. Homotopy Perturbation Method (HPM) is selected as a mathematical method to obtain an analytical solution of the 4th-order parabolic partial differential equation of motion of the rectangular plate of constant thickness viewed as a linear problem. This procedure is generalized to the nonlinear problem of the rectangular plate with variable thickness and an analytical solution can also be obtained. Sound power is used as a parameter to investigate the acoustic radiation of soundboards made from spruce using various bracing patterns. The sound power of soundboards made from Malaysian softwood such as damar minyak, sempilor or podo are investigated to determine the viability of replacing spruce as future materials for soundboards of Classical guitars.

Keywords: rectangular plates, analytical solution, homotopy perturbation, natural frequencies

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Authors: Paul V. Thomas, Mostafa S. A. Elsayed, Denis Walch

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Airframe structural optimization at different design stages results in new mass and stiffness distributions which modify the critical design loads envelop. Determination of aircraft critical loads is an extensive analysis procedure which involves simulating the aircraft at thousands of load cases as defined in the certification requirements. It is computationally prohibitive to use a Global Finite Element Model (GFEM) for the load analysis, hence reduced order structural models are required which closely represent the dynamic characteristics of the GFEM. This paper presents the implementation of Component Mode Synthesis (CMS) method for the generation of high fidelity Reduced Order Model (ROM) of complex airframes. Here, sub-structuring technique is used to divide the complex higher order airframe dynamical system into a set of subsystems. Each subsystem is reduced to fewer degrees of freedom using matrix projection onto a carefully chosen reduced order basis subspace. The reduced structural matrices are assembled for all the subsystems through interface coupling and the dynamic response of the total system is solved. The CMS method is employed to develop the ROM of a Bombardier Aerospace business jet which is coupled with an aerodynamic model for dynamic aeroelasticity loads analysis under gust turbulence. Another set of dynamic aeroelastic loads is also generated employing a stick model of the same aircraft. Stick model is the reduced order modelling methodology commonly used in the aerospace industry based on stiffness generation by unitary loading application. The extracted aeroelastic loads from both models are compared against those generated employing the GFEM. Critical loads Modal participation factors and modal characteristics of the different ROMs are investigated and compared against those of the GFEM. Results obtained show that the ROM generated using Craig Bampton CMS reduction process has a superior dynamic characteristics compared to the stick model.

Keywords: component mode synthesis, craig bampton reduction method, dynamic aeroelasticity analysis, model order reduction

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Authors: Gayatri Kanwar

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The purpose of this research paper is to explore the power of myth in changing human lives; it establishes patterns in the human psyche, affects the way of thinking, as myths unveil various subjects, ideas, and challenges. Through mythological stories one comes to understand the images behind the emotions and feelings, they influence him as it changes his thought patterns, their therapeutic sets the individual on the path of healing and transforms human lives. Every civilization in the olden times had a vast source of myths which they lived by. They were not ordinary stories of everyday life, but exemplary cases narrated through oral traditions in a sacred manner revealed the 'way to live life'. The mythical stories have a spiritual touch which brought him to the acceptance of suffering or finding a solution to his life problems. In modern times, the significance of the age old myth has lost their touch. Each one of us bears countless stories inside ourselves of our own lives and all its happenings. Therefore, each being is a natural narrator. Everybody tells stories about their lives; hence, one tends to know oneself as well as seeks understanding of others through them. When one remembers their stories they speak in narratives. As stated by Jung, these narratives grow into a personal mythology one lives by. Nonetheless, there are times when one becomes stuck in their own stories or myths. Hence, mythology can change one’s perception and can open pathways to other ways of discovering, feeling and experiencing one’s lives.

Keywords: Power of Myths, Significance of myths in modern times, Transforming human lives, Benefits to Society

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Authors: S. K. M. Nzaba, H. H. Nyoni, B. Ntsendwana, B. B. Mamba, A. T. Kuvarega

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Azo dye effluents, released into water bodies are not only toxic to the ecosystem but also pose a serious impact on human health due to the carcinogenic and mutagenic effects of the compounds present in the dye discharge. Conventional water treatment methods such as adsorption, flocculation/coagulation and biological processes are not effective in completely removing most of the dyes and their natural degradation by-products. Advanced oxidation processes (AOPs) have proven to be effective technologies for complete mineralization of these recalcitrant pollutants. Therefore, there is a need for new technology that can solve the problem. Thus, this study examined the photocatalytic degradation of an azo dye brilliant black (BB) using non-metal/metal codoped TiO₂. N, Pt co-doped TiO₂ photocatalysts were prepared by a modified sol-gel method using amine-terminated polyamidoamine dendrimer generation 0 (PAMAM G0), amine-terminated polyamidoamine dendrimer generation 1 ( PAMAM G1) and hyperbranched polyethyleneimine (HPEI) as templates and source of nitrogen. Structural, morphological, and textural properties were evaluated using scanning electron microscopy coupled to energy dispersive X-ray spectroscopy (SEM/EDX), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), Fourier- transform infrared (FTIR), Raman spectroscopy (RS), photoluminescence (PL) and ultra-violet /visible spectroscopy (UV-Vis). The synthesized photocatalysts exhibited lower band gap energies as compared to the Degussa P-25 revealing a red shift in band gap towards the visible light absorption region. Photocatalytic activity of N, Pt co-doped TiO₂ was measured by the reaction of photocatalytic degradation of brilliant black (BB) dye. The N, metal codoped TiO₂ containing 0.5 wt. % of the metal consisted mainly of the anatase phase as confirmed by XRD results of all three samples, with a particle size range of 13–30 nm. The particles were largely spherical and shifted the absorption edge well into the visible region. Band gap reduction was more pronounced for the N, Pt HPEI (Pt 0.5 wt. %) codoped TiO₂ compared to PAMAM G0 and PAMAM G1. Consequently, codoping led to an enhancement in the photocatalytic activity of the materials for the degradation of brilliant black (BB).

Keywords: codoped TiO₂, dendrimer, photodegradation, wastewater

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Authors: Merouani Nawel, Belhattab Rachid

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Aristolochia longa L. (Aristolochiacea) is a native plant of Algeria used in traditional medicine. This study was devoted to the determination of polyphenols, flavonoids, and condensed tannins contents of Aristolochia longa L. after their extraction by using various solvents with different polarities (methanol, acetone and distilled water). These extracts were prepared from stem, leaves, fruits and rhizome. The antioxidant activity was determined using three in vitro assays methods: scavenging effect on DPPH, the reducing power assay and ẞ-carotene bleaching inhibition (CBI). The results obtained indicate that the acetone extracts from the aerial parts presented the highest contents of polyphenols. The results of The antioxidant activity showed that all extracts of Aristolochia longa L., prepared using different solvent, have diverse antioxidant capacities. However, the aerial parts methanol extract exhibited the highest antioxidant capacity of DPPH and reducing power (Respectively 55,04ug/ml±1,29 and 0,2 mg/ml±0,019 ). Nevertheless, the aerial parts acetone extract showed the highest antioxidant capacity in the test of ẞ-carotene bleaching inhibition with 57%. These preliminary results could be used to justify the traditional use of this plant and their bioactive substances could be exploited for therapeutic purposes such as antioxidant and antimicrobial.

Keywords: aristolochia longa l., polyphenols, flavonoids, condensed tannins, antioxidant activity

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Authors: Mohammad Borhani, Afshin Danehkar

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With the increase in population and the upward trend of energy demand, mankind has thought of using suppliers that guarantee a stable supply of energy, unlike fossil fuels, which, in addition to the widespread emission of greenhouse gases that one of the main factors in the destruction of the ozone layer and it will be finished in a short time in the not-so-distant future. In this regard, one of the sustainable ways of energy supply is the use of wind converters. That convert wind energy into electricity. For this reason, this research focused on wind turbines and their installation conditions. The main classification of wind turbines is based on the axis of rotation, which is divided into two groups: horizontal axis and vertical axis; each of these two types, with the advancement of technology in man-made environments such as cities, villages, airports, and other human environments can be installed and operated. The main difference between offshore and onshore wind turbines is their installation and foundation. Which are usually divided into five types; including of Monopile Wind Turbines, Jacket Wind Turbines, Tripile Wind Turbines, Gravity-Based Wind Turbines, and Floating Offshore Wind Turbines. For installation in a wind power plant requires an arrangement that produces electric power, the distance between the turbines is usually between 5 or 7 times the diameter of the rotor and if perpendicular to the wind direction be If they are 3 to 5 times the diameter of the rotor, they will be more efficient.

Keywords: wind farms, Savonius, Darrieus, offshore wind turbine, renewable energy

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Authors: Mohammad Hadi Khorashadi Zadeh ‎

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An entrepreneur is a manager or the owner of the commercial company that creates resources and money by risking and initiative. The Netpreneur is the capability to run an online business. It needs only the Connectivity. An Entrepreneur, as long as he has a service which the market demands can set up a feasible and viable trade with his Intellectual Capital as the principle input and the Connectivity Infrastructure as the only physical input. The internet is possibly the most significant revolution in science and technology that our generation could fantasize or imagine. It has introduced in various benefits to the society, culture, economics and politics. The entrepreneur is a premium member in the community. She/he provides services to the society and community including employment.

Keywords: entrepreneur, Netpreneur, intellectual capital, infrastructure

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Authors: Aliyu Mohammed Lawal

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The problems placed on the environment as a result of energy generation and usage in Nigeria is: potential damage to the environment health by CO, CO2, SOx, and NOx, effluent gas emissions and global warming. For instance in the year 2004 in Nigeria energy consumption was 58% oil and 34% natural gas but about 94 million metric tons of CO2 was emitted out of which 64% came from fossil fuels while about 35% came from fuel wood. The findings from this research on how to alleviate these problems are that long term sustainable development solutions should be enhanced globally; energy should be used more rationally renewable energy resources should be exploited and the existing emissions should be controlled to tolerate limits because the increase in energy demand in Nigeria places enormous strain on current energy facilities.

Keywords: effluent gas, emissions, NOx, SOx

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Authors: Alyaa M. Younes, Nermine Harraz, Mohammad H. Elwany

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Lithium ion batteries are currently used for many applications including satellites, electric vehicles and mobile electronics. Their ability to store relatively large amount of energy in a limited space make them most appropriate for critical applications. Evaluation of the life of these batteries and their reliability becomes crucial to the systems they support. Reliability of Li-Ion batteries has been mainly considered based on its lifetime. However, another important factor that can be considered critical in many applications such as in electric vehicles is the cycle duration. The present work presents the results of an experimental investigation on the degradation behavior of a Laptop Li-ion battery (type TKV2V) and the effect of applied load on the battery cycle time. The reliability was evaluated using an accelerated life test. Least squares linear regression with median rank estimation was used to estimate the Weibull distribution parameters needed for the reliability functions estimation. The probability density function, failure rate and reliability function under each of the applied loads were evaluated and compared. An inverse power model is introduced that can predict cycle time at any stress level given.

Keywords: accelerated life test, inverse power law, lithium-ion battery, reliability evaluation, Weibull distribution

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Authors: Cian O'Shea, Ross O'Halloran, Peter Haigh

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Wireless Sensor Networks (WSN) are Internet of Things (IoT) edge devices. They are becoming widely adopted in many industries, including health care, building energy management, and conditional monitoring. As the scale of WSN deployments increases, the cost and complexity of battery replacement and disposal become more significant and in time may become a barrier to adoption. Harvesting ambient energies provide a pathway to reducing dependence on batteries and in the future may lead to autonomously powered sensors. This work describes a simulation tool that enables the user to predict the battery life of a wireless sensor that utilizes energy harvesting to supplement the battery power. To create this simulator, all aspects of a typical WSN edge device were modelled including, sensors, transceiver, and microcontroller as well as the energy source components (batteries, solar cells, thermoelectric generators (TEG), supercapacitors and DC/DC converters). The tool allows the user to plug and play different pre characterized devices as well as add user-defined devices. The goal of this simulation tool is to predict the lifetime of a device and scope for extension using ambient energy sources.

Keywords: Wireless Sensor Network, IoT, edge device, simulation, solar cells, TEG, supercapacitor, energy harvesting

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Authors: Emma Garcia-Meca, Jennifer Martinez-Ferrero, Camino Ramon Llorens

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This paper provides insights into how narcissistic Chief Executive Officers (CEOs) influence the presence of women in top management teams (TMT). We also study whether a CEO's power and gender and the gender diversity of the firm's board moderate the relationship between CEO narcissism and TMT gender diversity. Our results reveal that narcissistic CEOs are less likely to support women in TMTs, confirming that CEO personality traits influence team structure. Further results suggest that this aversion increases as the CEO's power grows when female representation on boards decreases and when the CEO is a woman. This paper integrates theories that use the social psychology and upper echelon theories, offering a greater understanding of how CEO personality traits influence the structure of firms. We also contribute to the knowledge about how different governance characteristics can moderate the influence of narcissistic CEOs on women in TMTs, highlighting the relevance of governance traits that increase the effect of narcissism. The results demonstrate different female behavior toward promoting TMT gender equality depending on the specific position of women in the firm's hierarchy and their psychological attributes. We find that women directors support social identity values, and narcissistic female CEOs act like queen bees.

Keywords: gender diversity, board, corporate governance, female CEO, management

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Authors: Maryam Azish

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Russia, as an emerging global player in recent years, has projected a special place in the Middle East. Despite all the challenges it has faced over the years, it has always considered its presence in various fields with a strategy that has defined its maneuvering power as a level of competition and even confrontation with the United States. Therefore, its current approach is considered important as an influential actor in the Middle East. After the collapse of the Soviet Union, when the Russians withdrew completely from the Middle East, the American scene remained almost unrivaled by the Americans. With the start of the US-led war in Iraq and Afghanistan and the subsequent developments that led to the US military and political defeat, a new chapter in regional security was created in which ISIL and Taliban terrorism went along with the Arab Spring to destabilize the Middle East. Because of this, the Americans took every opportunity to strengthen their military presence. Iraq, Syria and Afghanistan have always been the three areas where terrorism was shaped, and the countries of the region have each reacted to this evil phenomenon accordingly. The West dealt with this phenomenon on a case-by-case basis in the general circumstances that created the fluid situation in the Arab countries and the region. Russian President Vladimir Putin accused the US of falling asleep in the face of ISIS and terrorism in Syria. In fact, this was an opportunity for the Russians to revive their presence in Syria. This article suggests that utilizing the recognition policy along with the constructivism theory will offer a better knowledge of Russia’s endeavors to endorse its international position. Accordingly, Russia’s distinctiveness and its ambitions for a situation of great power have played a vital role in shaping national interests and, subsequently, in foreign policy, in Putin's era in particular. The focal claim of the paper is that scrutinize Russia’s foreign policy with realistic methods cannot be attained. Consequently, with an aim to fill the prevailing vacuum, this study exploits the politics of acknowledgment in the context of constructivism to examine Russia’s foreign policy in the Middle East. The results of this paper show that the key aim of Russian foreign policy discourse, accompanied by increasing power and wealth, is to recognize and reinstate the position of great power in the universal system. The Syrian crisis has created an opportunity for Russia to unite its position in the developing global and regional order after ages of dynamic and prevalent existence in the Middle East as well as contradicting US unilateralism. In the meantime, the writer thinks that the question of identifying Russia’s position in the global system by the West has played a foremost role in serving its national interests.

Keywords: constructivism, foreign Policy, middle East, Russia, regionalism

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Authors: D. Artamonov, A. Tsibulnikova, I. Samusev, V. Bryukhanov, A. Kozhevnikov

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The synthesis and luminescent properties of Yb₂O₃, Nd₂O₃@Bi₂O₃ complex with upconversion generation are discussed in this work. The obtained samples were measured in the visible region of the spectrum under excitation with a wavelength of 980 nm. The studies showed that the obtained complexes have a high degree of stability and intense luminescence in the wavelength range of 400-750 nm. Consideration of the time dependence of the intensity of the upconversion luminescence allowed us to conclude that the enhancement of the intensity occurs in the time interval from 5 to 30 min, followed by the appearance of a stationary mode.

Keywords: lasers, luminescence, upconversion photonics, rare earth metals

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Authors: Hussaini Tunde Subairu

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Small and Medium Enterprises (SMEs) sectors serve as catalyst for employment generation, national growth, poverty reduction and economic development in developing and developed countries. However, in Nigeria despite copious and plethora of government policies and stimulus schemes directed at SMEs, the sector is still characterized by high rate of failure and discontinuities. This study therefore investigated owners/managers profile, firms characteristics and external factors as possible determinants of SMEs growth from selected SMEs in Kwara State. Primary data were sourced from 200 SMEs respondents registered with the National Association of Small and Medium Enterprises (NASMES) in Kwara State Central Senatorial District. Multiple Regressions Analysis (MRA) was used to analyze the relationship between dependent and independent variables, and pair wise correlation was employed to examine the relationship among independent variables. The Analysis of Variable (ANOVA) was employed to indicate the overall significant of the model The findings revealed that Analysis of variance (ANOVA) put the value of F-statistics at 420.45 and p-value at 0.000 was significant. The values of R2 and Adjusted R2 of 0.9643 and 0.9620 respectively suggested that 96 percent of variations in employment growth were explained by the explanatory variables. The level of technical and managerial education has t- value of 24.14 and p-value of 0.001, length of managers/owners experience in similar trade with t- value of 21.37 and p-value of 0.001, age of managers/owners with t- value of 42.98 and p-value of 0.001, firm age with t- value of 25.91 and p-value of 0.001, numbers of firms in a cluster with t- value of 7.20 and p-value of 0.001, access to formal finance with t-value of 5.56 and p-value of 0.001, firm technology innovation with t- value of 25.32 and p-value of 0.01, institutional support with t- value of 18.89 and p-value of 0.01, globalization with t- value of 9.78 and p-value of 0.01, and infrastructure with t-value of 10.75 and p-value of 0.01. The result also indicated that initial size has t-value of -1.71 and p-value of 0.090 which is consistent with Gibrat’s Law. The study concluded that owners/managers profile, firm specific characteristics and external factors substantially influenced employment growths of SMEs in the study area. Therefore, policy implication should enhance human capital development of SMEs owners/managers, and strengthen fiscal policy thrust through imposition on tariff regime to minimize effect of globalization. Governments at all level must support SMEs growth radically and enhance institutional support for SMEs growth and radically and significantly upgrading key infrastructure as rail/roads, rail, telecommunications, water and power.

Keywords: external factors, firm specific characteristics, owners / manager profile, small and medium enterprises

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Authors: Asiye Aydilek, Harun Aydilek

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We investigate the costs of various suboptimal allocations in housing, consumption, bond and stock holdings of a retiree in a setting with recursive utility, considering the extensive empirical evidence that investors make suboptimal decisions in different ways. We find that suboptimal stock holdings impose only modest costs on the retiree. This may have a merit in explaining the limited stock investment in the data. The cost of suboptimal bond holdings is higher than that of stocks, but still small. This may partially explain why many more people hold bonds compared to stocks. We find that positive deviations from the optimal level are less costly relative to the negative ones in suboptimal housing allocations. This may help us to clarify why the elderly are over consuming housing, as seen in the housing data. The cost of suboptimal consumption is quite high and the highest of all. Our paper suggests that, in terms of welfare, the decisions of how much of liquid wealth to use for consumption and for saving are more important than the decision about the composition of liquid savings. Suboptimal stock holdings are twice more costly in power utility and suboptimal bond holdings are twenty times more costly in recursive utility. Recursive utility is superior to power utility in terms of rationalizing many people's preference for bonds instead of stocks in investment.

Keywords: housing, recursive utility, retirement, suboptimal decisions, welfare cost

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Authors: Essa Njie

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One of the challenges that Africa needs to overcome for the sustenance of its democratic gains is to separate the state from the ruling party to avoid the latter’s attempt in monopolizing the former’s resources and institutions for political supremacy. But this separation must go along with the process of depoliticizing the civil services (separation from partisan politics) which have been politicized by incumbents to register electoral successes. While researches conducted on the Gambia’s democratic reality tend to have looked at a wide range of challenges confronting the country’s democratic progress, this paper focuses on state power monopolization and its impediment to democratic governance in the country. The paper explores the involvement of civil/public servants in partisan politics in the Gambia. It looks at the intertwined nature of the state and the ruling party as state resources could not be separated from that of the ruling party (lack of separation between political and non-political resources) in both Dawda Jawara and Yahya Jammeh eras, and how such affected the country’s democratic credential. The paper in particular addresses the need for the current government to depoliticize the country’s civil service and concomitantly separate the state from the ruling party by not monopolizing the former’s resources and institutions to galvanize political support.

Keywords: civil service, democratic consolidation, monopolisation, multi-party elections, public institutions, ruling party, state resources

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Authors: W. M. Ng, O. B. Iskender, L. Simonini, J. M. Gonzalez

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A multitude of factors, including mechanical imperfections of the deployment system and separation instance of satellites from launchers, oftentimes results in highly uncontrolled initial tumbling motion immediately after deployment. In particular, small satellites which are characteristically launched as a piggyback to a large rocket, are generally allocated a large time window to complete detumbling within the early orbit phase. Because of the saturation risk of the actuators, current algorithms are conservative to avoid draining excessive power in the detumbling phase. This work aims to enable time-optimal switching of control modes during the early phase, reducing the time required to transit from launch to sun-pointing mode for power budget conscious satellites. This assumes the usage of B-dot controller for detumbling and PD controller for pointing. Nonlinear Euler's rotation equations are used to represent the attitude dynamics of satellites and Commercial-off-the-shelf (COTS) reaction wheels and magnetorquers are used to perform the manoeuver. Simulation results will be based on a spacecraft attitude simulator and the use case will be for multiple orbits of launch deployment general to Low Earth Orbit (LEO) satellites.

Keywords: attitude control, detumbling, small satellites, spacecraft autonomy, time optimal control

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Authors: Priyanka Sharma, Manoj Jais, Poonam Gupta, Suraiya K. Ansari, Ravinder Kaur

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Introduction: As much as the Health Care is necessary for the population, so is the management of the Biomedical waste produced. Biomedical waste is a wide terminology used for the waste material produced during the diagnosis, treatment or immunization of human beings and animals, in research or in the production or testing of biological products. Biomedical waste management is a chain of processes from the point of generation of Biomedical waste to its final disposal in the correct and proper way, assigned for that particular type of waste. Any deviation from the said processes leads to improper disposal of Biomedical waste which itself is a major health hazard. Proper segregation of Biomedical waste is the key for Biomedical Waste management. Improper disposal of BMW can cause sharp injuries which may lead to HIV, Hepatitis-B virus, Hepatitis-C virus infections. Therefore, proper disposal of BMW is of upmost importance. Health care establishments segregate the Biomedical waste and dispose it as per the Biomedical waste management rules in India. Objectives: This study was done to observe the current trends of Biomedical waste generated in a tertiary care Hospital in Delhi. Methodology: Biomedical waste management rounds were conducted in the hospital wards. Relevant details were collected and analysed and sites with maximum Biomedical waste generation were identified. All the data was cross checked with the commons collection site. Results: The total amount of waste generated in the hospital during January 2014 till December 2014 was 6,39,547 kg, of which 70.5% was General (non-hazardous) waste and the rest 29.5% was BMW which consisted highly infectious waste (12.2%), disposable plastic waste (16.3%) and sharps (1%). The maximum quantity of Biomedical waste producing sites were Obstetrics and Gynaecology wards with a total Biomedical waste production of 45.8%, followed by Paediatrics, Surgery and Medicine wards with 21.2 %, 4.6% and 4.3% respectively. The maximum average Biomedical waste generated was by Obstetrics and Gynaecology ward with 0.7 kg/bed/day, followed by Paediatrics, Surgery and Medicine wards with 0.29, 0.28 and 0.18 kg/bed/day respectively. Conclusions: Hospitals should pay attention to the sites which produce a large amount of BMW to avoid improper segregation of Biomedical waste. Also, induction and refresher training Program of Biomedical waste management should be conducted to avoid improper management of Biomedical waste. Healthcare workers should be made aware of risks of poor Biomedical waste management.

Keywords: biomedical waste, biomedical waste management, hospital-tertiary care, New Delhi

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Authors: Yiquan Liao, Quanhong Jiang

Abstract:

Since terahertz was observed by German scientists, we have obtained terahertz through different generation technologies of broadband and narrowband. Then, with the development of semiconductor and other technologies, the imaging technology of terahertz has become increasingly perfect. From the earliest application of nondestructive testing in aviation to the present application of information transmission and human safety detection, the role of terahertz will shine in various fields. The weapons produced by terahertz were epoch-making, which is a crushing deterrent against technologically backward countries. At the same time, terahertz technology in the fields of imaging, medical and livelihood, communication and communication are for the well-being of the country and the people.

Keywords: terahertz, imaging, communication, medical treatment

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Authors: Muhammad Saleem Ullah Khan Sumbal, Eric Tsui, Ricky Cheong, Eric See To

Abstract:

Organizations are posed to a threat of valuable knowledge loss when employees leave either due to retirement, resignation, job change or because of disabilities e.g. death, etc. Due to changing economic conditions, globalization, and aging workforce, organizations are facing challenges regarding retention of valuable knowledge. On the one hand, large number of employees are going to retire in the organizations whereas on the other hand, younger generation does not want to work in a company for a long time and there is an increasing trend of frequent job change among the new generation. Because of these factors, organizations need to make sure that they capture the knowledge of employee before (s)he walks out of the door. The first step in this process is to know what type of knowledge employee possesses and whether this knowledge is important for the organization. Researchers reveal in the literature that despite the serious consequences of knowledge loss in terms of organizational productivity and competitive advantage, there has not been much work done in the area of knowledge loss assessment of departing employees. An important step in the knowledge retention process is to determine the critical ‘at risk’ knowledge. Thus, knowledge loss risk assessment is a process by which organizations can gauge the importance of knowledge of the departing employee. The purpose of this study is to explore this topic of knowledge loss risk assessment by conducting a qualitative study in oil and gas sector. By engaging in dialogues with managers and executives of the organizations through in-depth interviews and adopting a grounded methodology approach, the research will explore; i) Are there any measures adopted by organizations to assess the risk of knowledge loss from departing employees? ii) Which factors are crucial for knowledge loss assessment in the organizations? iii) How can we prioritize the employees for knowledge retention according to their criticality? Grounded theory approach is used when there is not much knowledge available in the area under research and thus new knowledge is generated about the topic through an in-depth exploration of the topic by using methods such as interviews and using a systematic approach to analyze the data. The outcome of the study will generate a model for the risk of knowledge loss through factors such as the likelihood of knowledge loss, the consequence/impact of knowledge loss and quality of the knowledge loss of departing employees. Initial results show that knowledge loss assessment is quite crucial for the organizations and it helps in determining what types of knowledge employees possess e.g. organizations knowledge, subject matter expertise or relationships knowledge. Based on that, it can be assessed which employee is more important for the organizations and how to prioritize the knowledge retention process for departing employees.

Keywords: knowledge loss, risk assessment, departing employees, Hong Kong organizations

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Authors: Sumaira Saleem, Sajjad Hussain, Asma Kashif Shahzad, Hina Shaheen

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This study aims at exploring the relationship between language and ideology and how such relationships are represented in the analysis of spoken texts, following Van Dijk’s Socio Cognitive Model (2002). In this study, it is tried to show that political Talk shows broadcast by Private TV channels are working apparatuses of ideology and store meanings which are not always obvious for readers. This analysis was about the situation created by Arslan Iftkhar, the son of ex-Chief Justice of Pakistan, Iftikhar Muhammad Chaudry and PTI Chief Imran Khan. Arslan Iftikhar submitted an application against Imran Khan that he is not able to become a member of parliament of Pakistan. In the application, he demanded the documents, which are submitted by Imran Khan at the time of Election to the Election Commission of Pakistan. Murad Ali from PTI also submitted an application against PM Nawaz Sharif to the Election Commission of Pakistan for providing the copies. It also suggests that these talk shows mystify the agency of processes by using various strategies. In other words, critical text analyses reveal how these choices enable speakers to manipulate the realizations of agency and power in the representation of action to produce particular meanings which are not always explicit for all readers.

Keywords: ECP, CDA, socio cognitive model, ideology, TV channels, power

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Authors: Aman Kaur, Colin Ribton, Wamadeva Balachandaran

Abstract:

Electron beam welding due to its inherent advantages is being extensively used for material processing where high precision is required. Especially in aerospace or nuclear industries, there are high quality requirements and the cost of materials and processes is very high which makes it very important to ensure the beam quality is maintained and checked prior to carrying out the welds. Although the processes in these industries are highly controlled, however, even the minor changes in the operating parameters of the electron gun can make large enough variations in the beam quality that can result in poor welding. To measure the beam quality a simple device has been designed that can be used at high powers. The device consists of two slits in x and y axis which collects a small portion of the beam current when the beam is deflected over the slits. The signals received from the device are processed in data acquisition hardware and the dedicated software developed for the device. The device has been used in controlled laboratory environments to analyse the signals and the weld quality relationships by varying the focus current. The results showed matching trends in the weld dimensions and the beam characteristics. Further experimental work is being carried out to determine the ability of the device and signal processing software to detect subtle changes in the beam quality and to relate these to the physical weld quality indicators.

Keywords: electron beam welding, beam quality, high power, weld quality indicators

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Authors: Victor H. Benitez, Ramon V. Armas-Flores, Jesus H. Pacheco-Ramirez

Abstract:

Systems transforming solar energy into electrical power have emerged as a viable source of clean, renewable energy. Solar power tower technology is a good example of this type of system, which consists of several mobile mirrors, called heliostats, which reflect the sun's radiation to the same point, located on top of a tower at the center of heliostat field, for collection or transformation into another type of energy. The so-called Hermosillo’s Solar Platform (Plataforma Solar de Hermosillo, PSH, in Spanish) is a facility constituted with several heliostats, its aim and scope is for research purposes. In this paper, the implementation of a wireless communication system based on intelligent nodes is proposed in order to allow the communication and control of the heliostats in PSH. Intelligent nodes transmit information from one point to another, and can perform other actions that allow them to adapt to the conditions and limitations of a field of heliostats, thus achieving effective communication system. After deployment of the nodes in the heliostats, tests were conducted to measure the effectiveness of the communication, and determine the feasibility of using the proposed technologies. The test results were always positive, exceeding expectations held for its operation in the field of heliostats. Therefore, it was possible to validate the efficiency of the wireless communication system to be implemented in PSH, allowing communication and control of the heliostats.

Keywords: heliostat, intelligent node, solar energy, wireless communication

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Authors: Elham Mahdian, Reza Karazhian, Rahele Dehghan Tanha

Abstract:

Pepper (Capsicum annum L.) which belong to the family Solananceae, are known for their versatility as a vegetable crop and are consumed both as fresh vegetables or dehydrated for spices. Pepper is considered an excellent source of bioactive nutrients. Ascorbic acid, carotenoids and phenolic compounds are its main antioxidant constituents. Ultrasound assisted extraction is an inexpensive, simple and efficient alternative to conventional extraction techniques. The mechanism of action for ultrasound-assisted extraction are attributed to cavitations, mechanical forces and thermal impact, which result in disruption of cells walls, reduce particle size, and enhance mass transfer across cell membranes. In this study, response surface methodology was used to optimize experimental conditions for ultrasonic assisted extraction of carotenoid compounds from Chili peppers. Variables were included extraction temperatures at 3 levels (30, 40 and 50 °C), extraction times at 3 levels (10, 25 and 40 minutes) and power at 3 levels (30, 60 and 90 %). It was observed that ultrasound waves applied at temperature of 49°C, time of 10 minutes and power 89 % resulted to the highest carotenoids contents (lycopene and β-carotene), while the lowest value was recorded in the control. Thus, results showed that ultrasound waves have strong impact on extraction of carotenoids from pepper.

Keywords: carotenoids, optimization, pepper, response surface methodology

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Authors: Soon-Gil Yoon, Min-Ju Choi, Sung-Ho Shin, Junghyo Nah, Jin-Seok Choi, Hyun-A Song, Goeun Choi, Jin-Ho Choy

Abstract:

Layered double hydroxides (LDHs) with positively charged brucite-like layers and negatively charged interlayer anions are considered a critical nanoscale building block with potential for application in catalysts, biological sensors, and optical, electrical, and magnetic devices. LDHs also have a great potential as an energy conversion device, a key component in common modern electronics. Although LDHs are theoretically predicted to be centrosymmetric, we report here the first observations of the flexoelectric nature of LDHs and demonstrate their potential as an effective energy conversion material. We clearly show a linear energy conversion relationship between the output powers and curvature radius via bending with both the LDH nanosheets and thin films, revealing a direct evidence for flexoelectric effects. These findings potentially open up avenues to incorporate a flexoelectric coupling phenomenon into centrosymmetric materials such as LDHs and to harvest high-power energy using LDH nanosheets. In the present study, for enhancement of the output power, Zn-Al:LDH nanosheets were composited with piezoelectric CH3NH3PbI3 (MAPbI3) dye films and their enhanced energy harvesting was demonstrated in detail.

Keywords: layered double hydroxides, flexoelectric, piezoelectric, energy harvesting

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