Search results for: maintenance free operating period (MFOP)

Authors: Christian T. Lystbaek

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Background: The importance of innovation management has traditionally been ascribed to private production companies, however, there is an increasing interest in public services innovation management. One of the major theoretical challenges arising from this situation is to understand public values justifying public services innovation management. However, there is not single and stable definition of public value in the literature. The research question guiding this paper is: What is the supposed added value operating in the public sphere? Methodology: The study takes an action research strategy. This is highly contextualized methodology, which is enacted within a particular set of social relations into which on expects to integrate the results. As such, this research strategy is particularly well suited for its potential to generate results that can be applied by managers. The aim of action research is to produce proposals with a creative dimension capable of compelling actors to act in a new and pertinent way in relation to the situations they encounter. The context of the study is a workshop on public services innovation within elderly care. The workshop brought together different actors, such as managers, personnel and two groups of users-citizens (elderly clients and their relatives). The process was designed as an extension of the co-construction methods inherent in action research. Scenario methods and focus groups were applied to generate dialogue. The main strength of these techniques is to gather and exploit as much data as possible by exposing the discourse of justification used by the actors to explain or justify their points of view when interacting with others on a given subject. The approach does not directly interrogate the actors on their values, but allows their values to emerge through debate and dialogue. Findings: The public values related to public services innovation management in elderly care were identified in two steps. In the first step, identification of values, values were identified in the discussions. Through continuous analysis of the data, a network of interrelated values was developed. In the second step, tracking group consensus, we then ascertained the degree to which the meaning attributed to the value was common to the participants, classifying the degree of consensus as high, intermediate or low. High consensus corresponds to strong convergence in meaning, intermediate to generally shared meanings between participants, and low to divergences regarding the meaning between participants. Only values with high or intermediate degree of consensus were retained in the analysis. Conclusion: The study shows that the fundamental criterion for justifying public services innovation management is the capacity for actors to enact public values in their work. In the workshop, we identified two categories of public values, intrinsic value and behavioural values, and a list of more specific values.

Keywords: public services innovation management, public value, co-creation, action research

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Authors: Linh Tong

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This paper aims to contribute to the understanding of key education reforms in Vietnam from 1945 to 2017, which reflects an evolution of socio-political needs of the Socialist Republic of Vietnam throughout this period. It explores the contextual conditions, motivations and ambitions influencing the formation of the education reforms in Vietnam. It also looks, from an applied practical perspective, at the influence of politics on education policy-making. The research methodology includes a content analysis of curriculum designs proposed by the Ministry of Education and Training, relevant resolutions and executive orders passed by the National Assembly and the Prime Minister, as well as interviews with experts and key stakeholders. The results point to a particular configuration of factors which have been inspiring the shape and substance of these reforms and which have most certainly influenced their implementation. This configuration evolves from the immediate needs to erase illiteracy and cultivate socialist economic model at the beginning of Vietnam’s independence in 1945-1975, to a renewed urge to adopt market-oriented economy in 1986 and cautiously communicate with the outside world until 2000s, and to currently a demonstrated desire to fully integrate into the global economy and tackle with rising concerns about national security (the South China Sea Dispute), environmental sustainability, construction of a knowledge economy, and a rule-of-law society. Overall, the paper attempts to map Vietnam’s socio-political needs with the changing sets of goals and expected outcomes in teaching and learning methodologies and practices as introduced in Vietnamese key education reforms.

Keywords: curriculum development, knowledge society, national security, politics of education policy-making, Vietnam's education reforms

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Authors: Yagmur Kocaoglu, Nurtekin Erkmen

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The aim of this study was to determine effects of elastic resistance band training on body composition and postural control in sedentary women. Thirty-four sedentary females participated voluntarily for this study. Subjects' age was 21.88 ± 1.63 years, height was 161.50 ± 4.45 cm, and weight was 59.47 ± 7.03 kg. Participants were randomly placed into one of two groups (Experimental = 17, Control = 17). The elastic resistance training program lasted 8 weeks with 3 sessions per week. Experimental Group performed elastic resistance band training with red color for first 3 weeks, blue color for second 3 weeks and for last 2 weeks. The subjects carried out exercises 3 set, 10-15 repetitions with 15 seconds rest between exercises. The rest between sets was 30 seconds. The subjects underwent a standard warm-up for 10 minutes in every session. The elastic resistance training lasted 40 minutes for each session. After the training, all subjects performed a standard cool down for 10 minutes in each session. After and before 8 weeks training period, all subjects in experimental group and control group participated body composition and postural control measurements. Independent t-Test and Mann Whitney U Test were conducted to compare differences between experimental and control groups. Paired t-Test and Wilcoxon Z Test were used to compare differences between pre and posttests. There is no significant difference between pre and posttests in BMI (p>0.05). After the elastic resistance training, postural control scores and body fat significantly decreased in experimental group (p<0.05). In conclusion, it can be concluded that elastic resistance training improves postural control and body composition in sedentary women.

Keywords: body composition, elastic resistance band, postural control, sedentary women

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Authors: Agah Tugrul Korucu, Mustafa Mucahit Gundogdu, Tarık Gencturk, Ahmet Yucel

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Countries are developing big projects and supplying financial resource for developing technological substructure and integrating technology into the education. In Turkey, the Ministry of Education, with the aim of integrating ICT into learning and teaching processes, created a project named increasing occasions and normalizing the technology movement. FATIH Project with this project, the aim is to create teaching environments which are enriched with technology. In orientating people with the technology and integrating technology into the education, teacher and teacher candidates have a big responsibility. While teachers are using technology in lesson, the devices in class and the methods developed are important factors. The aim of this research is to examine awareness, and foresight about FATIH Project in different aspects. This study was conducted during the practice period of the second semester in the 2014-2015 academic years. The working group of the research was created from 209 teacher candidates which are from different teaching departments in the Ahmet Kelesoglu Education Faculty of Necmettin Erbakan University. Scanning model was used in this research. In research, as a getting data tool evaluation of “opinion about FATIH Project: awareness, foresight and expectation scale” which was developed by Karal et. al.; personal information form which was developed by researchers were used. Cronbach coefficient which is the reliability of the scale is 0.91. In analyzing the data, statistical package program average, standard deviation, percentage, correlation, t-test and variance analysis test were used.

Keywords: Fatih Project, information and communication technologies, information technology integration, views on the Fatih Project, technology integration in education

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Authors: K. Pankaj, R. K. Chaudhary, B. P. Mishra, S. Kochar

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Introduction: Consultation-Liaison psychiatry is a branch of psychiatry that includes clinical service, teaching and research. A consultation-liaison psychiatrist plays a role in having an expert opinion and linking the patients to other medical professionals and the patient’s bio-psycho-social aspects that may be leading to his/her symptoms. Consultation-Liaison psychiatry has been recognised as 'The guardian of the holistic approach to the patient', underlining its pre-eminent role in the management of patients who are admitted in a tertiary care hospital. Aims/ Objectives: The aim of the study was to analyse the utilization of psychiatric services and reasons for referrals in a tertiary care hospital. Materials and Methods: The study was done in a tertiary care hospital. The study included all the cases referred from different Inpatient wards to the psychiatry department for consultation. The study was conducted on 300 patients over a 3 month period. International classification of diseases 10 was used to diagnose the referred cases. Results: The majority of the referral was from the Medical Intensive care unit (22%) followed by general medical wards (18.66%). Majority of the referral was taken for altered sensorium (24.66%), followed by low mood or unexplained medical symptoms (21%). Majority of the referrals had a diagnosis of alcohol withdrawal syndrome (21%) as per International classification of diseases criteria, followed by unipolar Depression and Anxiety disorder (~ 14%), followed by Schizophrenia (5%) and Polysubstance abuse (2.6%). Conclusions: Our study concludes the importance of utilization of consultation-liaison psychiatric services. Also, the study signifies the need for sensitization of our colleagues regarding psychiatric sign and symptoms from time to time and seek psychiatric consult timely to decrease morbidity.

Keywords: consultation-liaison, psychiatry, referral, tertiary care hospital

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Authors: Priyanka Agrawal, Janou Koskamp, Amir Raoof, Mariette Wolthers

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Calcite is the main mineral found in carbonate rocks, which form significant hydrocarbon reservoirs and subsurface repositories for CO2 sequestration. The injected CO2 mixes with the reservoir fluid and disturbs the geochemical equilibrium, triggering calcite dissolution. Different combinations of fluid chemistry and injection rate may therefore result in different evolution of porosity, permeability and dissolution patterns. To model the changes in porosity and permeability Kozeny-Carman equation K∝〖(∅)〗^n is used, where K is permeability and ∅ is porosity. The value of n is mostly based on experimental data or pore network models. In pore network models, this derivation is based on accuracy of relation used for conductivity and pore volume change. In fact, at a single pore scale, this relationship is the result of the pore shape development due to dissolution. We have prepared a new reactive transport model for a single pore which simulates the complex chemical reaction of carbonic-acid induced calcite dissolution and subsequent pore-geometry evolution at a single pore scale. We use COMSOL Multiphysics package 5.3 for the simulation. COMSOL utilizes the arbitary-Lagrangian Eulerian (ALE) method for the free-moving domain boundary. We examined the effect of flow rate on the evolution of single pore shape profiles due to calcite dissolution. We used three flow rates to cover diffusion dominated and advection-dominated transport regimes. The fluid in diffusion dominated flow (Pe number 0.037 and 0.37) becomes less reactive along the pore length and thus produced non-uniform pore shapes. However, for the advection-dominated flow (Pe number 3.75), the fast velocity of the fluid keeps the fluid relatively more reactive towards the end of the pore length, thus yielding uniform pore shape. Different pore shapes in terms of inlet opening vs overall pore opening will have an impact on the relation between changing volumes and conductivity. We have related the shape of pore with the Pe number which controls the transport regimes. For every Pe number, we have derived the relation between conductivity and porosity. These relations will be used in the pore network model to get the porosity and permeability variation.

Keywords: single pore, reactive transport, calcite system, moving boundary

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Authors: Polina Prokopovich

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Despite the well-established dependence of cartilage mechanical properties on the frequency of the applied load, most research in the field is carried out in either load-free or constant load conditions because of the complexity of the equipment required for the determination of time-dependent properties. These simpler analyses provide a limited representation of cartilage properties thus greatly reducing the impact of the information gathered hindering the understanding of the mechanisms involved in this tissue replacement, development and pathology. More complex techniques could represent better investigative methods, but their uptake in cartilage research is limited by the highly specialised training required and cost of the equipment. There is, therefore, a clear need for alternative experimental approaches to cartilage testing to be deployed in research and clinical settings using more user-friendly and financial accessible devices. Frequency dependent material properties can be determined through rheometry that is an easy to use requiring a relatively inexpensive device; we present how a commercial rheometer can be adapted to determine the viscoelastic properties of articular cartilage. Frequency-sweep tests were run at various applied normal loads on immature, mature and trypsinased (as model of osteoarthritis) cartilage samples to determine the dynamic shear moduli (G*, G′ G″) of the tissues. Moduli increased with increasing frequency and applied load; mature cartilage had generally the highest moduli and GAG depleted samples the lowest. Hydraulic permeability (KH) was estimated from the rheological data and decreased with applied load; GAG depleted cartilage exhibited higher hydraulic permeability than either immature or mature tissues. The rheometer-based methodology developed was validated by the close comparison of the rheometer-obtained cartilage characteristics (G*, G′, G″, KH) with results obtained with more complex testing techniques available in literature. Rheometry is relatively simpler and does not require highly capital intensive machinery and staff training is more accessible; thus the use of a rheometer would represent a cost-effective approach for the determination of frequency-dependent properties of cartilage for more comprehensive and impactful results for both healthcare professional and R&D.

Keywords: tissue, rheometer, biomaterial, cartilage

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Authors: Khadidja Mebarki, Naceur Boussouar, Nabila Ihaddadene, M. Akermi

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Food products are particularly sensitive, since they concern the health of the consumer, whether it’s be from the health point of view or commercial, this kind of product must be subjected to rigorous controls, in order to prevent any fraud. Quality and safety are essential for food security, public health and economic development. The strengthening of food security is essential to increase food security which is considered reached when all individuals can at any time access safe and nutritious food they need to lead healthy and active lives. The objective of this project is to initiate a quality approach in the laboratories of the quality control and the repression of fraud. It will be directed towards the application of good laboratory practices, traceability, management of quality documents (quality, procedures and specification manual) and quality audits. And to prepare the ground for a possible accreditation by ISO 17025 standard of BECHAR laboratory’s. The project will take place in four main stages: 1- Preparation of an audit grid; 2- Realization of a quality audit according to the method of 5 M completed by a section on quality documentation; 3- Drafting of an audit report and proposal for recommendations; 4- Implementation of corrective actions on the ground. This last step consisted in the formalization of the cleaning disinfection plan; work on good hygiene practices, establishment of a mapping of processes and flow charts of the different processes of the laboratory, classifying quality documents and formalizing the process of document management. During the period of the study within the laboratory, all facets of the work were almost appreciated, as we participated in the expertise performed in within it.

Keywords: quality, management, ISO 17025 accreditation, GLP

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Authors: Nipun Ansal

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People guard their beliefs and opinions with their lives. Beliefs that they’ve formed over a period of time, and can go to any lengths to defy, desist from, resist and negate any outward stimulus that has the potential to shake them. Cognitive dissonance is term used to describe it in theory. And every human being, in order to defend himself from cognitive dissonance applies 4 rings of defense viz. Selective Exposure, Selective Perception, Selective Attention, and Selective Retention. This paper is a discursive analysis on how the onslaught of social media, complete with its intrusive weaponry, has amorphized the external ring of defense: the selective exposure. The stimulus-response model of communication is one of the most inherent model that encompasses communication behaviours of children and elderly, individual and masses, humans and animals alike. The paper deliberates on how information bombardment through the uncontrollable channels of the social media, Facebook and Twitter in particular, have dismantled our outer sphere of exposure, leading users online to a state of constant dissonance, and thus feeding impulsive action-taking. It applies case study method citing an example to corroborate how knowledge generation has given in to the information overload and the effect it has on decision making. With stimulus increasing in number of encounters, opinion formation precedes knowledge because of the increased demand of participation and decrease in time for the information to permeate from the outer sphere of exposure to the sphere of retention, which of course, is through perception and attention. This paper discusses the challenge posed by this fleeting, stimulus rich, peer-dominated media on the traditional models of communication and meaning-generation.

Keywords: communication, discretion, exposure, social media, stimulus

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Authors: Majid Javanmard

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Edible mushrooms are those agricultural products which contain high quantity of protein and can have special role in human diet. So search for methods to increase their shelf life is important. One of these strategies can be use of active packaging for absorb the ethylene which has been studied in present study. In this study, initially, production of impregnating zeolite with potassium permanganate has been studied with zeolite clinoptiolite available in iran. After that, these ethylene scavengers were placed in the package of edible mushrooms and then transferred to the refrigerator with temperature 4c for a period of 20 days. Each 5 days, several experiments accomplished on edible mushrooms such as weight loss, moisture content, color, texture, bacterial experiments and sensory evaluation. After production of impregnating zeolite with potassium permanganate (with a concentration of %2.5, %5, %7.5, %10 and %12.5) by zeolite type clinoptiolite (with mesh 35 and 60), samples have been analyzed with gas chromatography and titration with sodium oxalate. The results showed that zeolite by concentration of %5, %7.5 and %10 potassium permanganate and mesh 60 have a higher efficiency. Results from the experiments on edible mushrooms proved that impregnated zeolite with potassium permanganate have a meaningful influence in prevent the weight loss, decrease of moisture content and L-value, increase of a-value and overall color change (ΔE) and decrease of firmness texture of mushrooms. In addition, these absorbents can influence on decrease microbial load (mesophilic bacteria) rather than control. Generally, concluded that the impregnated zeolite with 10% permanganate potassium has a high efficiency on increase the shelf life of fresh edible mushrooms.

Keywords: active packaging, ethylene scavenger, zeolite clinoptiolite, permanganate potassium, shelf life

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Authors: Sarah Alamolhoda, Kevin J. Smith, Xiaotao Bi, Naoko Ellis

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For millennials, biomass has been the most important source of fuel used to produce energy. Energy derived from biomass is renewable by re-growth of biomass. Various technologies are used to convert biomass to potential renewable products including combustion, gasification, pyrolysis and fermentation. Gasification is the incomplete combustion of biomass in a controlled environment that results in valuable products such as syngas, biooil and biochar. Syngas is a combustible gas consisting of hydrogen (H₂), carbon monoxide (CO), carbon dioxide (CO₂), and traces of methane (CH₄) and nitrogen (N₂). Cleaned syngas can be used as a turbine fuel to generate electricity, raw material for hydrogen and synthetic natural gas production, or as the anode gas of solid oxide fuel cells. In this work, syngas as a product of woody biomass gasification in British Columbia, Canada, was introduced to two consecutive fixed bed reactors to perform a catalytic water gas shift reaction followed by a catalytic methanation reaction. The water gas shift reaction is a well-established industrial process and used to increase the hydrogen content of the syngas before the methanation process. Catalysts were used in the process since both reactions are reversible exothermic, and thermodynamically preferred at lower temperatures while kinetically favored at elevated temperatures. The water gas shift reactor and the methanation reactor were packed with Cu-based catalyst and Ni-based catalyst, respectively. Simulated syngas with different percentages of CO, H₂, CH₄, and CO₂ were fed to the reactors to investigate the effect of operating conditions in the unit. The water gas shift reaction experiments were done in the temperature of 150 ˚C to 200 ˚C, and the pressure of 550 kPa to 830 kPa. Similarly, methanation experiments were run in the temperature of 300 ˚C to 400 ˚C, and the pressure of 2340 kPa to 3450 kPa. The Methanation reaction reached 98% of CO conversion at 340 ˚C and 3450 kPa, in which more than half of CO was converted to CH₄. Increasing the reaction temperature caused reduction in the CO conversion and increase in the CH₄ selectivity. The process was designed to be renewable and release low greenhouse gas emissions. Syngas is a clean burning fuel, however by going through water gas shift reaction, toxic CO was removed, and hydrogen as a green fuel was produced. Moreover, in the methanation process, the syngas energy was transformed to a fuel with higher energy density (per volume) leading to reduction in the amount of required fuel that flows through the equipment and improvement in the process efficiency. Natural gas is about 3.5 times more efficient (energy/ volume) than hydrogen and easier to store and transport. When modification of existing infrastructure is not practical, the partial conversion of renewable hydrogen to natural gas (with up to 15% hydrogen content), the efficiency would be preserved while greenhouse gas emission footprint is eliminated.

Keywords: renewable natural gas, methane, hydrogen, gasification, syngas, catalysis, fuel

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Authors: John Abish, Bibin John

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Liquid-liquid flow in horizontal pipe is investigated in order to reveal the flow patterns arising from the co-existed flow of oil and water. The main focus of the study is to identify the feasibility of reducing the pumping power requirements of petroleum transportation lines by having an annular flow of water around the thick oil core. This idea makes oil transportation cheaper and easier. The present study uses computational fluid dynamics techniques to model oil-water flows with liquids of similar density and varying viscosity. The simulation of the flow is conducted using commercial package Ansys Fluent. Flow domain modeling and grid generation accomplished through ICEM CFD. The horizontal pipe is modeled with two different inlets and meshed with O-Grid mesh. The standard k-ε turbulence scheme along with the volume of fluid (VOF) multiphase modeling method is used to simulate the oil-water flow. Transient flow simulations carried out for a total period of 30s showed significant reduction in pressure drop while employing core annular flow concept. This study also reveals the effect of viscosity ratio, mass flow rates of individual fluids and ration of superficial velocities on the pressure drop across the pipe length. Contours of velocity and volume fractions are employed along with pressure predictions to assess the effectiveness of this proposed concept quantitatively as well as qualitatively. The outcome of the present study is found to be very relevant for the petrochemical industries.

Keywords: computational fluid dynamics, core-annular flows, frictional flow resistance, oil transportation, pressure drop

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Authors: Hamide Aydin, Banu Karaman, Ayhan Bozkurt, Umran Kurtan

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Recently, Proton Conducting Gel Polymer Electrolytes (GPEs) have drawn much attention in supercapacitor applications due to their physical and electrochemical characteristics and stability conditions for low temperatures. In this research, PVA-H2SO4-H3BO3 GPE has been used for electric-double layer capacitor (EDLCs) application, in which electrospun free-standing carbon nanofibers are used as electrodes. Introduced PVA-H2SO4-H3BO3 GPE behaves as both separator and the electrolyte in the supercapacitor. Symmetric Swagelok cells including GPEs were assembled via using two electrode arrangements and the electrochemical properties were searched. Electrochemical performance studies demonstrated that PVA-H2SO4-H3BO3 GPE had a maximum specific capacitance (Cs) of 134 F g-1 and showed great capacitance retention (%100) after 1000 charge/discharge cycles. Furthermore, PVA-H2SO4-H3BO3 GPE yielded an energy density of 67 Wh kg-1 with a corresponding power density of 1000 W kg-1 at a current density of 1 A g-1. PVA-H2SO4 based polymer electrolyte was produced according to following procedure; Firstly, 1 g of commercial PVA was dissolved in distilled water at 90°C and stirred until getting transparent solution. This was followed by addition of the diluted H2SO4 (1 g of H2SO4 in a distilled water) to the solution to obtain PVA-H2SO4. PVA-H2SO4-H3BO3 based polymer electrolyte was produced by dissolving H3BO3 in hot distilled water and then inserted into the PVA-H2SO4 solution. The mole fraction was arranged to ¼ of the PVA repeating unit. After the stirring 2 h at RT, gel polymer electrolytes were obtained. The final electrolytes for supercapacitor testing included 20% of water in weight. Several blending combinations of PVA/H2SO4 and H3BO3 were studied to observe the optimized combination in terms of conductivity as well as electrolyte stability. As the amount of boric acid increased in the matrix, excess sulfuric acid was excluded due to cross linking, especially at lower solvent content. This resulted in the reduction of proton conductivity. Therefore, the mole fraction of H3BO3 was chosen as ¼ of PVA repeating unit. Within this optimized limits, the polymer electrolytes showed better conductivities as well as stability.

Keywords: electrical double layer capacitor, energy density, gel polymer electrolyte, ultracapacitor

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Authors: C. Yin, B. Zhang, Y. Liu, J. Cai

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Airborne EM (AEM) is an effective geophysical exploration tool, especially suitable for ridged mountain areas. In these areas, topography will have serious effects on AEM system responses. However, until now little study has been reported on topographic effect on airborne EM systems. In this paper, an edge-based unstructured finite-element (FE) method is developed for 3D topographic modeling for both frequency and time-domain airborne EM systems. Starting from the frequency-domain Maxwell equations, a vector Helmholtz equation is derived to obtain a stable and accurate solution. Considering that the AEM transmitter and receiver are both located in the air, the scattered field method is used in our modeling. The Galerkin method is applied to discretize the Helmholtz equation for the final FE equations. Solving the FE equations, the frequency-domain AEM responses are obtained. To accelerate the calculation speed, the response of source in free-space is used as the primary field and the PARDISO direct solver is used to deal with the problem with multiple transmitting sources. After calculating the frequency-domain AEM responses, a Hankel’s transform is applied to obtain the time-domain AEM responses. To check the accuracy of present algorithm and to analyze the characteristic of topographic effect on airborne EM systems, both the frequency- and time-domain AEM responses for 3 model groups are simulated: 1) a flat half-space model that has a semi-analytical solution of EM response; 2) a valley or hill earth model; 3) a valley or hill earth with an abnormal body embedded. Numerical experiments show that close to the node points of the topography, AEM responses demonstrate sharp changes. Special attentions need to be paid to the topographic effects when interpreting AEM survey data over rugged topographic areas. Besides, the profile of the AEM responses presents a mirror relation with the topographic earth surface. In comparison to the topographic effect that mainly occurs at the high-frequency end and early time channels, the EM responses of underground conductors mainly occur at low frequencies and later time channels. For the signal of the same time channel, the dB/dt field reflects the change of conductivity better than the B-field. The research of this paper will serve airborne EM in the identification and correction of the topographic effects.

Keywords: 3D, Airborne EM, forward modeling, topographic effect

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Authors: Shao-Chi Chien, Ying-Ju Chen, Chiao-Yu Tseng, Wan-Ting Lee, Yi-Wen Cheng

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Dr. George Leslie Mackay arrived at Takoukang (now Port of Kaohsiung) in Taiwan on December 30, 1871. When Dr. Mackay dedicated at Taiwan for 30 years, he has been an important factor in such areas as preaching, medical and engaged in education. Many researchers have thoroughly studied Dr. Mackay's travels to understand his impact on the state of education, medicine and religion in Taiwan. In the 30-year period of hard work, Dr. Mackay's made outstanding influence on the church in Taiwan. Therefore, the present study will be the mission of the establishment of hospitals, schools, churches which preaching, education, and medicine whether there are related the number of comparisons to explore. According to The Diaries of George Leslie Mackay, our research uses the Geographic Information System (GIS) to map the location of Dr. Mackay's travel in Taiwan and compares it with today's local churches, hospitals, and schools whether there are related the number of comparisons to explore. Therefore, our research focuses on the whole of Taiwan, divided into missionary, medical and education as the main content of the three major parts. Additionally, use of point layer, the surface layer of the property table to establish, in-depth mission of Dr. Mackay's development in Taiwan and Today's comparison. The results will be based on the classification of three different colors pictures that the distance of Mackay's contribution of preaching, medicine, and education. Our research will be compared with the current churches, hospitals, schools and the past churches, hospitals, schools. The results of the present study will provide a reference for future research.

Keywords: George Leslie Mackay, geographic information system, spatial distribution, color categories analysis

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Authors: Hsiu-Chuan Hsueh, Kuei-Feng Shen Jr., Chia-Ling Chao, Hui-Chuan Pan

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This article described a 75 years old woman who has suffered from intestinal perforation and accepted surgery with temporary enterostomy, the operation makes her depressed, refused relatives and friend's care, facing low willingness to participate in various activities due to fear of changing body appearance caused by surgery and leave enterostomy. The author collected information through observation talks, physical evaluation, and medical records during the period of care from November 14 to November 30, 2016, we used the four aspects of physiology, psychology, society and spirituality as a whole sexual assessment to establish the nursing problems of patient, included of acute pain, disturbance of body image,coping ineffective individual. For patient care issues, to encouraged case to express their inner feelings and take part in self-care programs through providing good therapeutic interpersonal relationships with their families. However, it provided clear information about the disease and follow-up treatment plan, give compliments in a timely manner, enhanced self-confidence of individual cases and their motivation to participate in self-care of stoma, further face the disease in a positive manner. At the same time, cross-section team care model and individual care measures were developed to enhance the care skills after returning home and at the same time assist the individual in facing the psychological impact caused by stoma. Hope to provide this experience, as a reference for the future care of the disease.

Keywords: enterostomy, intestinal perforation, nursing experience, ostomy

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Authors: Nicola Menga, Giuseppe Carbone

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Although contact mechanics has been widely focused on the study of contacts between half-space, it has been recently pointed out that in presence of finite thickness elastic layers the results of the contact problem show significant difference in terms of the main contact quantities (e.g. contact area, penetration, mean pressure, etc.). Actually, there exist a wide range of industrial application demanding for this kind of studies, such as seals leakage prediction or pressure-sensitive coatings for electrical applications. In this work, we focus on the contact between a rigid profile and an elastic layer of thickness h confined under two different configurations: rigid constrain and applied uniform pressure. The elastic problem at hand has been formalized following Green’s function method and then numerically solved by means of a matrix inversion. We study different contact conditions, both considering and neglecting adhesive interactions at the interface. This leads to different solution techniques: Adhesive contacts equilibrium solution is found, in term of contact area for given penetration, making stationary the total free energy of the system; whereas, adhesiveless contacts are addressed defining an equilibrium criterion, again on the contact area, relying on the fracture mechanics stress intensity factor KI. In particular, we make the KI vanish at the edges of the contact area, as peculiar for adhesiveless elastic contacts. The results are obtained in terms of contact area, penetration, and mean pressure for both adhesive and adhesiveless contact conditions. As expected, in the case of a uniform applied pressure the slab turns out much more compliant than the rigidly constrained one. Indeed, we have observed that the peak value of the contact pressure, for both the adhesive and adhesiveless condition, is much higher for the rigidly constrained configuration than in the case of applied uniform pressure. Furthermore, we observed that, for little contact area, both systems behave the same and the pull-off occurs at approximately the same contact area and mean contact pressure. This is an expected result since in this condition the ratio between the layers thickness and the contact area is very high and both layer configurations recover the half-space behavior where the pull-off occurrence is mainly controlled by the adhesive interactions, which are kept constant among the cases.

Keywords: contact mechanics, adhesion, friction, thick layer

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Authors: Yutong Wan, John N. Wood

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Introduction: SCN9A encoded Nav1.7 is an ideal therapeutic target with minimal side effects for the pharmaceutical industry because SCN9A variants can cause both human gains of function pain-related mutations and loss of function pain-free mutations. This study reviews the clinical effectiveness of existing Nav1.7 inhibitors, which theoretically should be powerful analgesics. Methods: A systematic review is conducted on the effectiveness of current Nav1.7 blockers undergoing clinical trials. Studies were mainly extracted from PubMed, U.S. National Library of Medicine Clinical Trials, World Health Organization International Clinical Trials Registry, ISRCTN registry platform, and Integrated Research Approval System by NHS. Only studies with full text available and those conducted using double-blinded, placebo controlled, and randomised designs and reporting at least one analgesic measurement were included. Results: Overall, 61 trials were screened, and eight studies covering PF 05089771 (Pfizer), TV 45070 (Teva & Xenon), and BIIB074 (Biogen) met the inclusion criteria. Most studies were excluded because results were not published. All three compounds demonstrated insignificant analgesic effects, and the comparison between PF 05089771 and pregabalin/ibuprofen showed that PF 05089771 was a much weaker analgesic. All three drug candidates only have mild side effects, indicating the potentials for further investigation of Nav1.7 antagonists. Discussion: The failure of current Nav1.7 small molecule inhibitors might attribute to ignorance of the key role of endogenous systems in Nav1.7 null mutants, the lack of selectivity and blocking potency, and central impermeability. The synergistic combination of analgesic drugs, a recent UCL patent, combining a small dose of Nav1.7 blockers and opioids or enkephalinase inhibitors dramatically enhanced the analgesic effects. Conclusion: The current clinical testing Nav1.7 blockers are generally disappointing. However, the newer generation of Nav1.7 targeting analgesics has overcome the major constraints of its predecessors.

Keywords: chronic pain, Nav1.7 blockers, SCN9A, systematic review

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Authors: Taru Hakanen, Mervi Murtonen

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This study aims to increase understanding of the transition of business models in servitization. The significance of service in all business has increased dramatically during the past decades. Service-dominant logic (SDL) describes this change in the economy and questions the goods-dominant logic on which business has primarily been based in the past. A business model canvas is one of the most cited and used tools in defining end developing business models. The starting point of this paper lies in the notion that the traditional business model canvas is inherently goods-oriented and best suits for product-based business. However, the basic differences between goods and services necessitate changes in business model representations when proceeding in servitization. Therefore, new knowledge is needed on how the conception of business model and the business model canvas as its representation should be altered in servitized firms in order to better serve business developers and inter-firm co-creation. That is to say, compared to products, services are intangible and they are co-produced between the supplier and the customer. Value is always co-created in interaction between a supplier and a customer, and customer experience primarily depends on how well the interaction succeeds between the actors. The role of service experience is even stronger in service business compared to product business, as services are co-produced with the customer. This paper provides business model developers with a service business model canvas, which takes into account the intangible, interactive, and relational nature of service. The study employs a design science approach that contributes to theory development via design artifacts. This study utilizes qualitative data gathered in workshops with ten companies from various industries. In particular, key differences between Goods-dominant logic (GDL) and SDL-based business models are identified when an industrial firm proceeds in servitization. As the result of the study, an updated version of the business model canvas is provided based on service-dominant logic. The service business model canvas ensures a stronger customer focus and includes aspects salient for services, such as interaction between companies, service co-production, and customer experience. It can be used for the analysis and development of a current service business model of a company or for designing a new business model. It facilitates customer-focused new service design and service development. It aids in the identification of development needs, and facilitates the creation of a common view of the business model. Therefore, the service business model canvas can be regarded as a boundary object, which facilitates the creation of a common understanding of the business model between several actors involved. The study contributes to the business model and service business development disciplines by providing a managerial tool for practitioners in service development. It also provides research insight into how servitization challenges companies’ business models.

Keywords: boundary object, business model canvas, managerial tool, service-dominant logic

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Authors: Tanya Anand, Arun Kandasamy, L. N. Suman

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Family based therapy for adolescent substance abuse has been studied to be effective in the West. Whereas, based on literature review, family therapy and interventions for adolescent substance abuse is still in its nascent stages in India. A multidimensional perspective to treatment has been indicated consistently in the Indian literature, but standardized therapy which addresses early substance abuse, from a social-ecological perspective has not been developed and studied for Indian population. While numerous researches have been conducted in India on the need of engaging the family in therapy for the purpose of symptom reduction, long-term maintenance of gains, and reducing family burnout, distress and dysfunction; a family based model in the Indian context has not been developed and tried, to the best of our knowledge. Hence, from the aim of building a model to treat adolescent substance abuse within the family context, experts in the area of mental health and deaddiction were interviewed to inform upon the clinical difficulties, challenges, uniqueness that Indian families present with. The integration of indigenous techniques that would be helpful in engaging families of young individuals with difficulties were also explored. Eight experts' who were interviewed, have 10-30 years of experience in working with families and substance users. An open-ended interview was conducted with the experts individually and audio-recorded. The interviews were then transcribed and subjected to qualitative analysis for building a framework and treatment guideline. Additionally, interviews with patients and their parents were conducted to elicit ‘felt needs’. The results of the analysis revealed culture-specific issues widely experienced within Indian families by adolescents and young adults, centering around the theme of Individuation versus collective identity and living. Substance abuse, in this framework, was found to be perceived as one of the maladaptive ways of the youth to disengage from the family and attempt at individuation and the responsibilities that are considered entitlements in the culture. On the other hand, interviews with family members revealed them to be engaging in inconsistent patterns of care and parenting. This was experienced and observed in terms of fostering interdependence within the family, sometimes within adverse socio-economic and societal conditions, where enacted and perceived stigma kept the individual and family members in a vicious loop of maladaptive coping patterns, dysfunctional family arrangements, and often leading to burnout with poor help seeking. The paper inform upon a framework that lays down the foundation for assessments, planning, case management and therapist competencies, required to address alcohol and drug issues in an Indian family context with such etiological factors at its heart. This paper will cover qualitative results of the interviews and present a model that may guide mental health professionals for treatment of adolescent substance use and family therapy.

Keywords: Indian families, family therapy, de-addiction, adolescent, youth, substance abuse, behavioral issues, felt needs, culture, etiology, model building, framework development, interviews

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Authors: Khaleel Alyahya, Faizah Alotaibi

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The coronavirus disease 19 (COVID-19) pandemic has caused an increase in general fear and anxiety around the globe. With the public health measures, including lockdown and travel restrictions, the COVID-19 period further resulted in a sudden increase in the vulnerability of people too ill mental health. This becomes greater among individuals who have a history of mental illness or are undergoing treatment and do not have easy access to medication and medical consultations. The study aims to measure the impact of COVID-19 and the degree of distress with the DASS scale on the mental health of residents living in Saudi Arabia. The study is a quantitative, observational, and cross-sectional conducted in Saudi Arabia to measure the impact of COVID-19 on the mental health of both citizens and residents of Saudi Arabia during pandemics. The study ran from February 2021 to June 2021, and a validated questionnaire was used. The targeted population of the study was Saudi citizens and non-Saudi residents. A sample size of 800 participants was calculated with a single proportion formula at 95% level of significance and 5% allowable error. The result revealed that participants who were always doing exercise experienced the lowest level of depression, anxiety, and stress. The highest prevalence of severe and extremely severe depression was among participants who sometimes do exercise at 53.2% for each. Similar results were obtained for anxiety and stress, where the extremely severe form was reported by those who sometimes did exercise at 54.8% and 72.2%, respectively. There was an inverse association between physical activity levels and levels of depression, anxiety, and stress during the COVID-19. Similarly, the levels of depression, anxiety, and stress differed significantly according to the exercise frequency during COVID-19.

Keywords: mental, COVID-19, pandemic, lockdown, depression, anxiety, stress

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Authors: K. A. Ramesh

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Purpose: The study is to find out the effect of isolated and combined aerobic and anaerobic interval training on stride length and stride frequency of Soccer players. Method(s): To achieve this purpose, 45 women Soccer players who participated in the Anna University, Tamilnadu, India. Intercollegiate Tournament was selected as subjects and were randomly divided into three equal groups of fifteen each, such as an anaerobic interval training group (group-I), anaerobic interval training group (group-II) and combined aerobic-anaerobic interval training group (group-III). The training program was conducted three days per weeks for a period of six weeks. Stride length and Stride frequency was selected as dependent variables. All the subjects of the three groups were tested on selected criterion variables at prior to and immediately after the training program. The concepts of dependent test were employed to find out the significant improvement due to the influence of training programs on all the selected criterion variables. The analysis of covariance (ANCOVA) was also used to analyze the significant difference, if, any among the experimental groups. Result(s): The result of the study revealed that combined group was higher than aerobic interval training and anaerobic interval training groups. Conclusion(s): It was concluded that when experimental groups were compared with each other, the combined aerobic – anaerobic interval training program was found to be greater than the aerobic and the anaerobic interval training programs on the development of stride length and stride frequency. High intensity, combined aerobic – anaerobic interval training program can be carried out in a more soccer specific way than plain running.

Keywords: stride length, stride frequency, interval training, soccer

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Authors: Lāsma Cielava, Daina Jonkus, Līga Paura

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The age of first calving (AFC) is one of the most important factors that have a significant impact on cow productivity in different lactations and its whole life. A belated AFC leads to reduced reproductive performance and it is one of the main reasons for reduced longevity. Cows that calved in time period from 2001-2007 and in this time finished at least four lactations were included in the database. Data were obtained from 68841 crossbred Holstein Black and White (HM), crossbred Latvian Brown (LB), and Latvian Brown genetic resources (LBGR) cows. Cows were distributed in four groups depending on age at first calving. The longest lifespan was conducted for LBGR cows, but they were also characterized with lowest lifetime milk yield and life day milk yield. HM breed cows had the shortest lifespan, but in the lifespan of 2862.2 days was obtained in average 37916.4 kg milk accordingly 13.2 kg milk in one life day. HM breed cows were also characterized with longer calving intervals (CI) in first four lactations, but LBGR cows had the shortest CI in the study group. Age at first calving significantly affected the length of CI in different lactations (p<0.05). HM cows that first time calved >30 months old in the fourth lactation had the longest CI in all study groups (421.4 days). The LBGR cows were characterized with the shortest CI, but there was slight increase in second and third lactation. Age at first calving had a significant impact on cows’ age in each calving time. In the analysis, cow group was conducted that cows with age at first calving <24 months or in average 580.5 days at the time of fifth calving were 2156.7 days (5.9 years) old, but cows with age at first calving >30 months (932.6 days) at the time of fifth calving were 2560.9 days (7.3 years) old.

Keywords: age at first calving, calving interval, longevity, milk yield

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Authors: Samad Lotfollahzadeh

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To evaluate the effect of intramuscular administration of vitamin A during dry period in pregnant dairy cows, which already received it in their daily ration, on vitamin A status of neonatal calves, a total of 30 cows were randomly selected and divided to two main groups; treatment and control group. Animals in the treatment group were subdivided into two groups. Single intramuscular injection of 2000000 IU vitamin A; was carried in 10 dairy cows at 7 months of pregnancy (group 1). In the second group of treated animals (10 cows) the injection was performed in 8 months of pregnancy (group 2). Ten pregnant dairy cows were received saline injection as placebo and selected as the control group. Blood samples were collected from experimental dairy cows at 7 and 8 months of pregnancy as well as their newborn calves’ pre and after colostrum intake. There was no significant difference between vitamin A and β- carotene concentration of dairy cows of three groups in two last months of pregnancy (P > 0.05). Vitamin A concentration of calves of two treatment groups before and after receiving of colostrum were significantly higher than that in the control group (P < 0.05). There was no significant difference between serum concentrations of vitamin A in calves of two treated groups (P > 0.05). β- Carotene concentration of serum samples of dairy cows and neonatal calves of three groups were not significantly different as compared with together. From results of the present study it can be concluded that daily supplementation of vitamin A in late pregnancy in dairy cows may not compensate the calves need for vitamin A and single injection of this vitamin A during dry either in 7 or 8 months of pregnancy can significantly increase level of vitamin A in their colostrum and neonatal calves.

Keywords: dry cow, beta carotene, newborn calves, vitamin A, dry cows

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Authors: Same Noel Ngando, Yakub Abdulfatai Olatunji

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Renewable energy micro-grids, such as those powered by solar or wind energy, are often intermittent in nature. This means that the amount of energy generated by these systems can vary depending on weather conditions or other factors, which can make it difficult to ensure a steady supply of power. To address this issue, energy storage systems have been developed to increase the reliability of renewable energy micro-grids. Battery systems have been the dominant energy storage technology for renewable energy micro-grids. Batteries can store large amounts of energy in a relatively small and compact package, making them easy to install and maintain in a micro-grid setting. Additionally, batteries can be quickly charged and discharged, allowing them to respond quickly to changes in energy demand. However, the process involved in recycling batteries is quite costly and difficult. An alternative energy storage system that is gaining popularity is hydrogen storage. Hydrogen is a versatile energy carrier that can be produced from renewable energy sources such as solar or wind. It can be stored in large quantities at low cost, making it suitable for long-distance mass storage. Unlike batteries, hydrogen does not degrade over time, so it can be stored for extended periods without the need for frequent maintenance or replacement, allowing it to be used as a backup power source when the micro-grid is not generating enough energy to meet demand. When hydrogen is needed, it can be converted back into electricity through a fuel cell. Energy consumption data is got from a particular residential area in Daegu, South Korea, and the data is processed and analyzed. From the analysis, the total energy demand is calculated, and different hybrid energy system configurations are designed using HOMER Pro (Hybrid Optimization for Multiple Energy Resources) and MATLAB software. A techno-economic and environmental comparison and life cycle assessment (LCA) of the different configurations using battery and hydrogen as storage systems are carried out. The various scenarios included PV-hydrogen-grid system, PV-hydrogen-grid-wind, PV-hydrogen-grid-biomass, PV-hydrogen-wind, PV-hydrogen-biomass, biomass-hydrogen, wind-hydrogen, PV-battery-grid-wind, PV- battery -grid-biomass, PV- battery -wind, PV- battery -biomass, and biomass- battery. From the analysis, the least cost system for the location was the PV-hydrogen-grid system, with a net present cost of about USD 9,529,161. Even though all scenarios were environmentally friendly, taking into account the recycling cost and pollution involved in battery systems, all systems with hydrogen as a storage system produced better results. In conclusion, hydrogen is becoming a very prominent energy storage solution for renewable energy micro-grids. It is easier to store compared with electric power, so it is suitable for long-distance mass storage. Hydrogen storage systems have several advantages over battery systems, including flexibility, long-term stability, and low environmental impact. The cost of hydrogen storage is still relatively high, but it is expected to decrease as more hydrogen production, and storage infrastructure is built. With the growing focus on renewable energy and the need to reduce greenhouse gas emissions, hydrogen is expected to play an increasingly important role in the energy storage landscape.

Keywords: renewable energy systems, microgrid, hydrogen production, energy storage systems

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Authors: Sachin Jain, Daniel Perez-Astudillo, Dunia A. Bachour, Antonio P. Sanfilippo

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The future of solar energy in Qatar is evolving steadily. Hence, high-quality spatial solar radiation data is of the uttermost requirement for any planning and commissioning of solar technology. Generally, two types of solar radiation data are available: satellite data and ground observations. Satellite solar radiation data is developed by the physical and statistical model. Ground data is collected by solar radiation measurement stations. The ground data is of high quality. However, they are limited to distributed point locations with the high cost of installation and maintenance for the ground stations. On the other hand, satellite solar radiation data is continuous and available throughout geographical locations, but they are relatively less accurate than ground data. To utilize the advantage of both data, a product has been developed here which provides spatial continuity and higher accuracy than any of the data alone. The popular satellite databases: National Solar radiation Data Base, NSRDB (PSM V3 model, spatial resolution: 4 km) is chosen here for merging with ground-measured solar radiation measurement in Qatar. The spatial distribution of ground solar radiation measurement stations is comprehensive in Qatar, with a network of 13 ground stations. The monthly average of the daily total Global Horizontal Irradiation (GHI) component from ground and satellite data is used for error analysis. The normalized root means square error (NRMSE) values of 3.31%, 6.53%, and 6.63% for October, November, and December 2019 were observed respectively when comparing in-situ and NSRDB data. The method is based on the Empirical Bayesian Kriging Regression Prediction model available in ArcGIS, ESRI. The workflow of the algorithm is based on the combination of regression and kriging methods. A regression model (OLS, ordinary least square) is fitted between the ground and NSBRD data points. A semi-variogram is fitted into the experimental semi-variogram obtained from the residuals. The kriging residuals obtained after fitting the semi-variogram model were added to NSRBD data predicted values obtained from the regression model to obtain the final predicted values. The NRMSE values obtained after merging are respectively 1.84%, 1.28%, and 1.81% for October, November, and December 2019. One more explanatory variable, that is the ground elevation, has been incorporated in the regression and kriging methods to reduce the error and to provide higher spatial resolution (30 m). The final GHI maps have been created after merging, and NRMSE values of 1.24%, 1.28%, and 1.28% have been observed for October, November, and December 2019, respectively. The proposed merging method has proven as a highly accurate method. An additional method is also proposed here to generate calibrated maps by using regression and kriging model and further to use the calibrated model to generate solar radiation maps from the explanatory variable only when not enough historical ground data is available for long-term analysis. The NRMSE values obtained after the comparison of the calibrated maps with ground data are 5.60% and 5.31% for November and December 2019 month respectively.

Keywords: global horizontal irradiation, GIS, empirical bayesian kriging regression prediction, NSRDB

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Authors: Yunhan Zhang, Xiaopeng Li, Zhongxiao Peng

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Additive manufacturing (AM) possesses several key characteristics, including high design freedom, energy-efficient manufacturing process, reduced material waste, high resolution of finished products, and excellent performance of finished products. These advantages have garnered widespread attention and fueled rapid development in recent decades. AM has significantly broadened the spectrum of available materials in the manufacturing industry and is gradually replacing some traditionally manufactured parts. Similar to components produced via traditional methods, products manufactured through AM are susceptible to degradation caused by wear during their service life. Given the prevalence of 316L stainless steel (SS) parts and the limited research on the tribological behavior of 316L SS samples or products fabricated using AM technology, this study aims to investigate the degradation process and wear mechanisms of 316L SS disks fabricated using AM technology. The wear mechanisms and tribological performance of these AM-manufactured samples are compared with commercial 316L SS samples made using conventional methods. Additionally, methods to enhance the tribological performance of additive-manufactured SS samples are explored. Four disk samples with a diameter of 75 mm and a thickness of 10 mm are prepared. Two of them (Group A) are prepared from a purchased SS bar using a milling method. The other two disks (Group B), with the same dimensions, are made of Gas Atomized 316L Stainless Steel (size range: 15-45 µm) purchased from Carpenter Additive and produced using Laser Powder Bed Fusion (LPBF). Pin-on-disk tests are conducted on these disks, which have similar surface roughness and hardness levels. Multiple tests are carried out under various operating conditions, including varying loads and/or speeds, and the friction coefficients are measured during these tests. In addition, the evolution of the surface degradation processes is monitored by creating moulds of the wear tracks and quantitatively analyzing the surface morphologies of the mould images. This analysis involves quantifying the depth and width of the wear tracks and analyzing the wear debris generated during the wear processes. The wear mechanisms and wear performance of these two groups of SS samples are compared. The effects of load and speed on the friction coefficient and wear rate are investigated. The ultimate goal is to gain a better understanding of the surface degradation of additive-manufactured SS samples. This knowledge is crucial for enhancing their anti-wear performance and extending their service life.

Keywords: degradation process, additive manufacturing, stainless steel, surface features

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Authors: Sarath Chandran Nair S, Srinivas Kodati, Vasudevan R, Asraff A. K

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Spacecrafts generally employ liquid propulsion for their attitude and orbital maneuvers or raising it from geo-transfer orbit to geosynchronous orbit. Liquid propulsion systems use either mono-propellant or bi-propellants for generating thrust. These propellants are generally stored in either spherical tanks or cylindrical tanks with spherical end domes. The propellant tanks are provided with a propellant acquisition system/propellant management device along with vanes and their conical mounting structure to ensure propellant availability in the outlet for thrust generation even under a low/zero-gravity environment. Slosh is the free surface oscillations in partially filled containers under external disturbances. In a spacecraft, these can be due to control forces and due to varying acceleration. Knowledge of slosh and its effect due to internals is essential for understanding its stability through control stability studies. It is mathematically represented by a pendulum-mass model. It requires parameters such as slosh frequency, damping, sloshes mass and its location, etc. This paper enumerates various numerical and experimental methods used for evaluating the slosh parameters required for representing slosh. Numerical methods like finite element methods based on linear velocity potential theory and computational fluid dynamics based on Reynolds Averaged Navier Stokes equations are used for the detailed evaluation of slosh behavior in one of the spacecraft propellant tanks used in an Indian space mission. Experimental studies carried out on a scaled-down model are also discussed. Slosh parameters evaluated by different methods matched very well and finalized their dispersion bands based on experimental studies. It is observed that the presence of internals such as propellant management devices, including conical support structure, alters slosh parameters. These internals also offers one order higher damping compared to viscous/ smooth wall damping. It is an advantage factor for the stability of slosh. These slosh parameters are given for establishing slosh margins through control stability studies and finalize the spacecraft control system design.

Keywords: control stability, propellant tanks, slosh, spacecraft, slosh spacecraft

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Authors: Eric Mensah

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The effects of rapid urbanisation of tropical sub-Saharan developing cities on local and global climate are of great concern due to the negative impacts of Urban Heat Island (UHI) effects. The importance of urban parks, vegetative cover and forest reserves in these tropical cities have been undervalued with a rapid degradation and loss of these vegetative covers to urban developments which continue to cause an increase in daily mean temperatures and changes to local climatic conditions. Using Landsat data of the same months and period intervals, the spatial variations of land cover changes, temperature, and vegetation were examined to determine how vegetation improves local temperature and the effects of urbanisation on daily mean temperatures over the past 12 years. The remote sensing techniques of maximum likelihood supervised classification, land surface temperature retrieval technique, and normalised differential vegetation index techniques were used to analyse and create the land use land cover (LULC), land surface temperature (LST), and vegetation and non-vegetation cover maps respectively. Results from the study showed an increase in daily mean temperature by 0.80 °C as a result of rapid increase in urban area by 46.13 sq. km and loss of vegetative cover by 46.24 sq. km between 2005 and 2017. The LST map also shows the existence of UHI within the urban areas of Accra, the potential mitigating effects offered by the existence of forest and vegetative cover as demonstrated by the existence of cool islands around the Achimota ecological forest and University of Ghana botanical gardens areas.

Keywords: land surface temperature, climate, remote sensing, urbanisation

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Authors: Rosa Figueroa, Christopher Flores

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Text categorization is the problem of assigning a new document to a set of predetermined categories, on the basis of a training set of free-text data that contains documents whose category membership is known. To train a classification model, it is necessary to extract characteristics in the form of tokens that facilitate the learning and classification process. In text categorization, the feature extraction process involves the use of word sequences also known as N-grams. In general, it is expected that documents belonging to the same category share similar features. The Smith-Waterman (SW) algorithm is a dynamic programming algorithm that performs a local sequence alignment in order to determine similar regions between two strings or protein sequences. This work explores the use of SW algorithm as an alternative to feature extraction in text categorization. The dataset used for this purpose, contains 2,610 annotated documents with the classes Obese/Non-Obese. This dataset was represented in a matrix form using the Bag of Word approach. The score selected to represent the occurrence of the tokens in each document was the term frequency-inverse document frequency (TF-IDF). In order to extract features for classification, four experiments were conducted: the first experiment used SW to extract features, the second one used unigrams (single word), the third one used bigrams (two word sequence) and the last experiment used a combination of unigrams and bigrams to extract features for classification. To test the effectiveness of the extracted feature set for the four experiments, a Support Vector Machine (SVM) classifier was tuned using 20% of the dataset. The remaining 80% of the dataset together with 5-Fold Cross Validation were used to evaluate and compare the performance of the four experiments of feature extraction. Results from the tuning process suggest that SW performs better than the N-gram based feature extraction. These results were confirmed by using the remaining 80% of the dataset, where SW performed the best (accuracy = 97.10%, weighted average F-measure = 97.07%). The second best was obtained by the combination of unigrams-bigrams (accuracy = 96.04, weighted average F-measure = 95.97) closely followed by the bigrams (accuracy = 94.56%, weighted average F-measure = 94.46%) and finally unigrams (accuracy = 92.96%, weighted average F-measure = 92.90%).

Keywords: comorbidities, machine learning, obesity, Smith-Waterman algorithm

Procedia PDF Downloads 297