Search results for: controlled release rate

Authors: Suha K. Shihab, Zahid A. Khan, Aas Mohammad, Arshad Noor Siddiquee

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This paper presents the influence of cutting parameters (cutting speed, feed and depth of cut) on flank wear (VB) in turning of 52100 hard alloy steel using multilayer coated carbide insert under dry condition. Nine experiments were performed based on Taguchi’s L9 orthogonal array. Analysis of variance (ANOVA) was used to determine the effects of the cutting parameters on flank wear. The results of the study revealed that the cutting speed (A) and feed rate (B) are the dominant factors affecting flank wear, while the depth of cut (C) has not a significant effect. The optimal combination of the cutting parameters for flank wear is found to be A1B1C1. The mathematical model for flank wear is found to be statistically significant. The predicted and measured values of flank wear are found to be very close to each other.

Keywords: flank wear, hard turning, Taguchi approach, optimization

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Authors: Zaaraoui Abdelkader, Kerfah Rabeh, Noura Belkheir, Matene Elhacene

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The trapezoidal bluff body is a typical configuration of vortex shedding bodies. The aim of this work is to study flow behaviour over a trapezoidal cylinder at low Reynolds number. The geometry was constructed from a prototype device for measuring the volumetric flow-rate by counting vortices. Simulations were run for this geometry under steady and unsteady flow conditions using finite volume discretization. Laminar flow was investigated in this model with rigid walls and homogeneous incompressible Newtonian fluid. Calculations were performed for Reynolds number range 5 ≤ Re ≤ 180 and several flow parameters were documented. The present computations are in good agreement with the experimental observations and the numerical calculations by several investigators.

Keywords: bluff body, confined flow, numerical calculations, steady and unsteady flow, vortex shedding flow meter

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Authors: Ehab AbdulRazzaq Hussein

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Quantum cryptography (QC) is an emerging technology for secure key distribution with single-photon transmissions. In contrast to classical cryptographic schemes, the security of QC schemes is guaranteed by the fundamental laws of nature. Their security stems from the impossibility to distinguish non-orthogonal quantum states with certainty. A potential eavesdropper introduces errors in the transmissions, which can later be discovered by the legitimate participants of the communication. In this paper, the modeling approach is proposed for QC protocol BB84 using polarization coding. The single-photon system is assumed to be used in the designed models. Thus, Eve cannot use beam-splitting strategy to eavesdrop on the quantum channel transmission. The only eavesdropping strategy possible to Eve is the intercept/resend strategy. After quantum transmission of the QC protocol, the quantum bit error rate (QBER) is estimated and compared with a threshold value. If it is above this value the procedure must be stopped and performed later again.

Keywords: security, key distribution, cryptography, quantum protocols, Quantum Cryptography (QC), Quantum Key Distribution (QKD).

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Authors: Nouha Khediri, Mohammed Ben Ammar, Monji Kherallah

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Recently, facial emotion recognition (FER) has become increasingly essential to understand the state of the human mind. Accurately classifying emotion from the face is a challenging task. In this paper, we present a facial emotion recognition approach named CV-FER, benefiting from deep learning, especially CNN and VGG16. First, the data is pre-processed with data cleaning and data rotation. Then, we augment the data and proceed to our FER model, which contains five convolutions layers and five pooling layers. Finally, a softmax classifier is used in the output layer to recognize emotions. Based on the above contents, this paper reviews the works of facial emotion recognition based on deep learning. Experiments show that our model outperforms the other methods using the same FER2013 database and yields a recognition rate of 92%. We also put forward some suggestions for future work.

Keywords: CNN, deep-learning, facial emotion recognition, machine learning

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Authors: Mohammad Reza Ostad Ali Naghi Kashani, Esfanji Elia

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Nowadays, the amounts of companies which tend to have an Enterprise Resource Planning (ERP) application are increasing particularly in developing countries like Iran. ERP projects are expensive, time consuming, and complex, in addition the failure rate is high among these projects. It is important to know whether these projects could meet their goals or not. Furthermore, the area which should be improved should be identified. In this paper we made a framework to evaluate ERP projects success implementation. First, based on literature review we made a framework based on BSC model, financial, customer, processes, learning and knowledge, because of the importance of change management it was added to model. Then an organization was divided in three layers. We choose corporate, managerial, and operational levels. Then to find criteria to assess each aspect, we use Delphi method in two rounds. And for the second round we made a questionnaire and did some statistical tasks on them. Based on the statistical results some of them are accepted and others are rejected.

Keywords: ERP, BSC, ERP project evaluation, IT projects

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Authors: Tariq Mansoor, Lubos Hes, Vladimir Bajzik

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Socks comfort has great significance in our daily life. This significance even increased when we have undergone a work of low or high activity. It causes the sweating of our body with different rates. In this study, plain socks with differential fibre composition were wetted to saturated level. Then after successive intervals of conditioning, these socks are characterized by thermal resistance in dry and wet states. Theoretical thermal resistance is predicted by using combined filling coefficients and thermal conductivity of wet polymers instead of dry polymer (fibre) in different models. By this modification, different mathematical models could predict thermal resistance at different moisture levels. Furthermore, predicted thermal resistance by different models has reasonable correlation range between (0.84 -0.98) with experimental results in both dry (lab conditions moisture) and wet states. "This work is supported by Technical University of Liberec under SGC-2019. Project number is 21314".

Keywords: thermal resistance, mathematical model, plain socks, moisture loss rate

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Authors: El Hadji Mamadou Sonko, Mbaye Mbéguéré, Cheikh Diop, Linda Strande

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In new approaches that are being developed for the treatment of sludge, the valorization of by-product is increasingly encouraged. In this perspective, Echinochloa pyramidalis has been successfully tested in Cameroon. Echinochloa pyramidalis is an efficient forage plant in the treatment of faecal sludge. It provides high removal rates and biosolids of high agronomic value. Thus in order to advise the use of this plant in planted drying beds in Senegal its comparison with the plants long been used in the field deserves to be carried out. That is the aim of this study showing the influence of the nature of the plants on the drainage, the purifying performances and the quality of the biosolids. Echinochloa pyramidalis, Typha australis, and Phragmites australis are the three macrophytes used in this study. The drainage properties of the beds were monitored through the frequency of clogging, the percentage of recovered leachate and the dryness of the accumulated sludge. The development of plants was followed through the measurement of the density. The purification performances were evaluated from the incoming raw sludge flows and the outflows of leachate for parameters such as Total Solids (TS), Total Suspended Solids (TSS), Total Volatile Solids (TVS), Chemical Oxygen Demand (COD), Total Kjeldahl Nitrogen (TKN), Ammonia (NH₄⁺), Nitrate (NO₃⁻), Total Phosphorus (TP), Orthophosphorus (PO₄³⁻) and Ascaris eggs. The quality of the biosolids accumulated on the beds was measured after 3 months of maturation for parameters such as dryness, C/N ratio NH₄⁺/NO₃⁻ ratio, ammonia, Ascaris eggs. The results have shown that the recovered leachate volume is about 40.4%; 45.6% and 47.3%; the dryness about 41.7%; 38.7% and 28.7%, and clogging frequencies about 6.7%; 8.2% and 14.2% on average for the beds planted with Echinochloa pyramidalis, Typha australis and Phragmites australis respectively. The plants of Echinochloa pyramidalis (198.6 plants/m²) and Phragmites australis (138 plants/m²) have higher densities than Typha australis (90.3 plants/m²). The nature of the plants has no influence on the purification performance with reduction percentages around 80% or more for all the parameters followed whatever the nature of the plants. However, the concentrations of these various leachate pollutants are above the limit values of the Senegalese standard NS 05-061 for the release into the environment. The biosolids harvested after 3 months of maturation are all mature with C/N ratios around 10 for all the macrophytes. The NH₄⁺/NO₃⁻ ratio is lower than 1 except for the biosolids originating from the Echinochloa pyramidalis beds. The ammonia is also less than 0.4 g/kg except for biosolids from Typha australis beds. Biosolids are also rich in mineral elements. Their concentrations of Ascaris eggs are higher than the WHO recommendations despite a percentage of inactivation around 80%. These biosolids must be stored for an additional time or composted. From these results, the use of Echinochloa pyramidalis as the main macrophyte can be recommended in the various drying beds planted in sub-Saharan climate conditions.

Keywords: faecal sludge, nature of plants, quality of biosolids, treatment performances

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Authors: Mindaugas Zavalis

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Analysis of experimental tests data of bending one-way reinforced concrete slabs from various articles of science revealed that voided slabs with a grid of hollow plastic inserts inside have smaller mechani-cal and physical parameters compared to continuous cross-section slabs (solid slabs). The negative influence of a reinforced concrete slab is impacted by hollow plastic inserts, which make a grid of voids in the middle of the cross-sectional area of the reinforced concrete slab. A formed grid of voids reduces the slab’s stiffness, which influences the slab’s parameters of serviceability, like deflection and cracking. Prima-ry investigation of data established during experiments illustrates that cracks occur faster in the tensile surface of the voided slab under bend-ing compared to bending solid slab. It means that the crack bending moment force for the voided slab is smaller than the solid slab and the reduction can variate in the range of 14 – 40 %. Reduce of resistance to cracking can be controlled by changing a lot of factors: the shape of the plastic hallow insert, plastic insert height, steps between plastic in-serts, usage of prestressed reinforcement, the diameter of reinforcement bar, slab effective depth, the bottom cover thickness of concrete, effec-tive cross-section of the concrete area about reinforcement and etc. Mentioned parameters are used to evaluate crack width and step of cracking, but existing analytical calculation methods for cracking eval-uation of voided slab with plastic inserts are not so exact and the re-sults of cracking evaluation in this paper are higher than the results of analyzed experiments. Therefore, it was made analytically calculations according to experimental bending tests of voided reinforced concrete slabs with hollow plastic inserts to find and propose corrections for the evaluation of cracking for reinforced concrete voided slabs with hollow plastic inserts.

Keywords: voided slab, cracking, hallow plastic insert, bending, one-way reinforced concrete, serviceability

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Authors: A. Hany A. Khater, G. M. Mostafa, M. R. Badawy

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The techno-economic analysis of the nuclear desalination is a very important tool that enables studying of the mutual effects between the nuclear power plant and the coupled desalination plant under different operating conditions, and hence investigating the feasibility of safe and economical production of potable water. For this purpose, a comprehensive model for both technical and economic performance evaluation of the nuclear desalination has been prepared. The developed model has the capability to be used in performing a parametric study for the performance measuring parameters of the nuclear desalination system. Also a sensitivity analysis of varying important factors such as interest/discount rate, power plant availability, fossil fuel prices, purchased electricity price, nuclear fuel cost, and specific base cost for both power and water plant has been conducted.

Keywords: uclear desalination, PWR, MED, MED-TVC, MSF, RO

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Authors: Fruzsina Luca Kézér, Viktor Jurkovich, Ottó Szenci, János Tőzsér, Levente Kovács

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Positive interaction between people and animals could have a favorable effect on the welfare and production by reducing stress levels. However, to the repeated contact with humans (e.g. farm staff, veterinarians or herdsmen), animals may respond with escape behavior or avoidance, which both have negative effects on the ease of handling, welfare and may lead to the expression of aggressive behaviors. Rough or aversive handling can impair health and the function of the cardiac autonomic activity due to fear and stress, which also can be determined by certain parameters of heart rate variability (HRV). Although the essential relationships between fear from humans and basal tone of the autonomic nervous system were described by the authors previously, several questions remained unclear in terms of the associations between different coping strategies (behavioral syndromes) of the animals and physiological responsiveness to humans. The main goal of this study was to find out whether human behavior and emotions to the animals have an impact on cardiac function and behavior of animals with different coping styles in response situations. Therefore, in the present study, special (fear, approaching, restraint, novel arena, novel object) tests were performed on healthy, 2-year old heifers (n = 104) differing in coping styles [reactive (passive) vs. proactive (active) coping]. Animals were categorized as reactive or proactive based on the following tests: 1) aggressive behavior at the feeding bunk, 2) avoidance from an approaching person, 3) immobility, and 4) daily activity (number of posture changes). Heart rate, the high frequency (HF) component of HRV as a measure of vagal activity and the ratio between the low frequency (LF) and HF components (LF/HF ratio) as a parameter of sympathetic nervous system activity were calculated for all individual during lying posture (baseline) and for response situations in novel object, novel arena, and unfamiliar person tests (both for 5 min), respectively. The differences between baseline and response were compared between groups. Higher sympathetic (higher heart rates and LF/HF ratios) and lower parasympathetic activity (lower HF) was found for proactive animals in response situations than for reactive (passive) animals either during the novel object, the novel arena and the unfamiliar person test. It suggests that animals with different behavioral traits differ in their immediate autonomic adaptation to novelty and people. Based on our preliminary results, it seems, that the analysis of HRV can help to understand the physiological manifestation of responsiveness to novelty and human presence in dairy cattle with different behavioral syndromes.

Keywords: behavioral syndromes, human-cattle interaction, novel arena test, physiological responsiveness, proactive coping, reactive coping

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Authors: Shunpu Zhang

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We propose a new multiple test called the minPOP test for testing multiple hypotheses simultaneously. Under the assumption that the test statistics are independent, we show that the minPOP test has higher global power than the existing multiple testing methods. We further propose a stepwise multiple-testing procedure based on the minPOP test and two of its modified versions (the Double Truncated and Left Truncated minPOP tests). We show that these multiple tests have strong control of the family-wise error rate (FWER). A method for finding the p-values of the proposed tests after adjusting for multiplicity is also developed. Simulation results show that the Double Truncated and Left Truncated minPOP tests, in general, have a higher number of rejections than the existing multiple testing procedures.

Keywords: multiple test, single-step procedure, stepwise procedure, p-value for multiple testing

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Authors: José Maria, Vânia Laranjo, Luís Abrunhosa, António Inês

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The occurrence of mycotoxigenic moulds such as Aspergillus, Penicillium and Fusarium in food and feed has an important impact on public health, by the appearance of acute and chronic mycotoxicoses in humans and animals, which is more severe in the developing countries due to lack of food security, poverty and malnutrition. This mould contamination also constitutes a major economic problem due the lost of crop production. A great variety of filamentous fungi is able to produce highly toxic secondary metabolites known as mycotoxins. Most of the mycotoxins are carcinogenic, mutagenic, neurotoxic and immunosuppressive, being ochratoxin A (OTA) one of the most important. OTA is toxic to animals and humans, mainly due to its nephrotoxic properties. Several approaches have been developed for decontamination of mycotoxins in foods, such as, prevention of contamination, biodegradation of mycotoxins-containing food and feed with microorganisms or enzymes and inhibition or absorption of mycotoxin content of consumed food into the digestive tract. Some group of Gram-positive bacteria named lactic acid bacteria (LAB) are able to release some molecules that can influence the mould growth, improving the shelf life of many fermented products and reducing health risks due to exposure to mycotoxins. Some LAB are capable of mycotoxin detoxification. Recently our group was the first to describe the ability of LAB strains to biodegrade OTA, more specifically, Pediococcus parvulus strains isolated from Douro wines. The pathway of this biodegradation was identified previously in other microorganisms. OTA can be degraded through the hydrolysis of the amide bond that links the L-β-phenylalanine molecule to the ochratoxin alpha (OTα) a non toxic compound. It is known that some peptidases from different origins can mediate the hydrolysis reaction like, carboxypeptidase A an enzyme from the bovine pancreas, a commercial lipase and several commercial proteases. So, we wanted to have a better understanding of this OTA degradation process when LAB are involved and identify which molecules where present in this process. For achieving our aim we used some bioinformatics tools (BLAST, CLUSTALX2, CLC Sequence Viewer 7, Finch TV). We also designed specific primers and realized gene specific PCR. The template DNA used came from LAB strains samples of our previous work, and other DNA LAB strains isolated from elderberry fruit, silage, milk and sausages. Through the employment of bioinformatics tools it was possible to identify several proteins belonging to the carboxypeptidase family that participate in the process of OTA degradation, such as serine type D-Ala-D-Ala carboxypeptidase and membrane carboxypeptidase. In conclusions, this work has identified carboxypeptidase proteins being one of the molecules present in the OTA degradation process when LAB are involved.

Keywords: carboxypeptidase, lactic acid bacteria, mycotoxins, ochratoxin a.

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Authors: Lexuan Zhong, Chang-Seo Lee, Fariborz Haghighat, Stuart Batterman, John C. Little

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Ultraviolet photocatalytic oxidation (UV-PCO) technology has been recommended as a green approach to health indoor environment when it is integrated into mechanical ventilation systems for inorganic and organic compounds removal as well as energy saving due to less outdoor air intakes. Although much research has been devoted to UV-PCO, limited information is available on the UV-PCO behavior tested by the mixtures in literature. This project investigated UV-PCO performance and by-product generation using a single and a mixture of acetone and MEK at 100 ppb each in a single-pass duct system in an effort to obtain knowledge associated with competitive photochemical reactions involved in. The experiments were performed at 20 % RH, 22 °C, and a gas flow rate of 128 m3/h (75 cfm). Results show that acetone and MEK mutually reduced each other’s PCO removal efficiency, particularly negative removal efficiency for acetone. These findings were different from previous observation of facilitatory effects on the adsorption of acetone and MEK on photocatalyst surfaces.

Keywords: by-products, inhibitory effect, mixture, photocatalytic oxidation

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Authors: Hayder H. Kareem, Shunqi Pan

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Groundwater is a vital water resource in many areas in the world, particularly in the Middle-East region where the water resources become scarce and depleting. Sustainable management and planning of the groundwater resources become essential and urgent given the impact of the global climate change. In the recent years, numerical models have been widely used to predict the flow pattern and assess the water resources security, as well as the groundwater quality affected by the contaminants transported. In this study, MODFLOW is used to study the current status of groundwater resources and the risk of water resource security in the region centred at Al-Najaf City, which is located in the mid-west of Iraq and adjacent to the Euphrates River. In this study, a conceptual model is built using the geologic and hydrogeologic collected for the region, together with the Digital Elevation Model (DEM) data obtained from the "Global Land Cover Facility" (GLCF) and "United State Geological Survey" (USGS) for the study area. The computer model is also implemented with the distributions of 69 wells in the area with the steady pro-defined hydraulic head along its boundaries. The model is then applied with the recharge rate (from precipitation) of 7.55 mm/year, given from the analysis of the field data in the study area for the period of 1980-2014. The hydraulic conductivity from the measurements at the locations of wells is interpolated for model use. The model is calibrated with the measured hydraulic heads at the locations of 50 of 69 wells in the domain and results show a good agreement. The standard-error-of-estimate (SEE), root-mean-square errors (RMSE), Normalized RMSE and correlation coefficient are 0.297 m, 2.087 m, 6.899% and 0.971 respectively. Sensitivity analysis is also carried out, and it is found that the model is sensitive to recharge, particularly when the rate is greater than (15mm/year). Hydraulic conductivity is found to be another parameter which can affect the results significantly, therefore it requires high quality field data. The results show that there is a general flow pattern from the west to east of the study area, which agrees well with the observations and the gradient of the ground surface. It is found that with the current operational pumping rates of the wells in the area, a dry area is resulted in Al-Najaf City due to the large quantity of groundwater withdrawn. The computed water balance with the current operational pumping quantity shows that the Euphrates River supplies water into the groundwater of approximately 11759 m3/day, instead of gaining water of 11178 m3/day from the groundwater if no pumping from the wells. It is expected that the results obtained from the study can provide important information for the sustainable and effective planning and management of the regional groundwater resources for Al-Najaf City.

Keywords: Al-Najaf city, conceptual modelling, groundwater, unconfined aquifer, visual MODFLOW

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Authors: Mohamed M. Mashaly, Ahmed M. F. El Shiwi

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Background: Shoulder impingement syndrome is an encroachment of subacromial tissues, rotator cuff, subacromial bursa, and the long head of the biceps tendon, as a result of narrowing of the subacromial space. Activities requiring repetitive or sustained use of the arms over head often predispose the rotator cuff tendon to injury. Purpose: To compare between Combined effect therapeutic exercises and Shockwave therapy versus therapeutic exercises and phonophoresis in the treatment of shoulder impingement syndrome. Methods: Thirty patients diagnosed as shoulder impingement syndrome stage II Neer classification due to mechanical causes. Patients were randomly distributed into two equal groups. The first group consisted of 15 patients with a mean age of (45.46+8.64) received therapeutic exercises (stretching exercise of posterior shoulder capsule and strengthening exercises of shoulder muscles) and shockwave therapy (6000 shocks, 2000/session, 3 sessions, 2 weeks apart, 0.22mJ/mm^2) years. The second group consisted of 15 patients with a mean age of 46.26 (+ 8.05) received same therapeutic exercises and phonophoresis (3 times per week, each other day, for 4 consecutive weeks). Patients were evaluated pretreatment and post treatment for shoulder pain severity, shoulder functional disability, shoulder flexion, abduction and internal rotation motions. Results: Patients of both groups showed significant improvement in all the measured variables. In between groups difference the shock wave group showed a significant improvement in all measured variables than phonophoresis group. Interpretation/Conclusion: Combined effect of therapeutic exercises and shock wave were more effective than therapeutic exercises and phonophoresis on decreasing shoulder pain severity, shoulder functional disability, increasing in shoulder flexion, abduction, internal rotation in patients with shoulder impingement syndrome.

Keywords: shoulder impingement syndrome, therapeutic exercises, shockwave, phonophoresis

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Authors: G. Yanay-Ventura, H. Desivilya Syna, K. Michael

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Social businesses are based on the idea that an enterprise can be established for the sake of profit and, at the same time, with the aim of fulfilling social goals. Yet, the question of how these goals can be integrated in practice to derive parallel benefit in both realms still needs to be examined. Particularly notable in this context is the ‘governance challenge’ of social businesses, meaning the danger of the mission drifts from the social goal in the pursuit of good business. This study is based on an evaluation study of a social business that operates as a restaurant providing professional training to at-risk youth. The evaluation was based on the collection of a variety of data through interviews with stakeholders in the enterprise (directors and managers, business partners, social partners, and position holders in the restaurant and the social enterprise), a focus group consisting of the youth receiving the professional training, observations of the restaurant’s operation, and analysis of the social enterprise’s primary documents. The evaluation highlighted significant strengths of the social enterprise, including reaching relatively fast business sustainability, effective management of the restaurant, stable employment of the restaurant staff, and effective management of the social project. The social enterprise and business management have both enjoyed positive evaluations from a variety of stakeholders. Clearly, the restaurant was deemed by all a promising young business. However, the social project suffered from a 90% dropout rate among the youth entering its ranks, extreme monthly fluctuation in the number of youths participating, and a distinct minority of the youth who have succeeded in completing their training period. Possible explanations of the high dropout rate included the small number of cooks, which impeded the effectiveness of the training process and the provision of advanced cooking skills; lack of clarity regarding the essence and the elements of training; and lack of a meaningful peer group for the youth engaged in the program. Paradoxically, despite the stakeholders’ great appreciation for the social enterprise, the challenge of governability was also formidable, revealing a tangible risk of mission drift in the reduction of the social enterprise’s target population and a breach of the commitment made to the youth with regard to practical training. The risk of mission drifts emerged as a hidden and evasive issue for the stakeholders, who revealed a deep appreciation for the management and the outcomes of the social enterprise. The challenge of integration, therefore, requires an in-depth examination of how to maintain a successful business without hindering the achievement of the social goal. The study concludes that clear conceptualization of the training process and its aims, increased cooks’ participation in the social project, and novel conceptions with regard to the evaluation of success could serve to benefit the youth and impede mission drift.

Keywords: evaluation study, management, mission drift, social business

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Authors: Megha, Diksha, Seema Rani, Balwinder Kaur, Harminder Kaur

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Fe₃O₄@SiO₂@SB functionalized magnetic nanoparticles were synthesized and used to detect heavy metal ions such as Pb²⁺, Hg²⁺, and Cd²⁺ in water. The formation of Fe₃O₄@SiO₂@SB nanocatalyst was confirmed by XRD, SEM, TEM, and IR. The simultaneous determination of analyte cations was carried out using square wave anodic stripping voltammetry (SWASV). Investigation and optimisation were done to study how experimental variables affected the performance of the modified magnetic electrode. Pb²⁺, Hg²⁺, and Cd²⁺ were successfully detected using the designed sensor in the presence of various possibly interfering ions. The recovery rate was found to be 97.5% for Pb²⁺, 96.2% for Hg²⁺, 103.5% for Cd²⁺. The electrochemical sensor was also employed to determine the presence of heavy metal ions in drinking water samples, which are well below the World Health Organization (WHO) guidelines.

Keywords: magnetic nanoparticles, heavy metal ions, electrochemical sensor, environmental water samples

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Authors: J. M. Kim, Y. W. Jung, E. Lee, Y. K. Kwack, , S. K. Sim*

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Cyanobacterial blooms in lakes, reservoirs, and rivers have been environmental and social issues due to its toxicity, odor, etc. Among the cyanotoxins, microcystins exist mostly within the cyanobacterial cells, and they are released from the cells. Therefore, an innovative technology is needed to detoxify the harvested microalgae for environment-friendly utilization of the harvested microalgae. This study develops detoxification method of microcystins in the harvested microalgae and recycling harvested microalgae with food waste using salt-tolerant mushroom strains and natural ecosystem decomposer. During this eco-friendly organic waste recycling process, diverse bacteria or various enzymes of the salt-tolerant mushroom strains decompose the microystins and cyclic peptides. Using PHLC/Mass analysis, it was verified that 99.8% of the microcystins of the harvested microalgae was detoxified in the harvested mushroom as well as in the recycled organic biomass. Further study is planned to verify the decomposition mechanisms of the microcystins by the bacteria or enzymes. In this study, the harvested microalgae is mixed with the food waste, and then the mixed toxic organic waste is used as mushroom compost by adjusting the water content of about 70% using cellulose such as sawdust cocopeats and cottonseeds. The mushroom compost is bottled, sterilized, and salt-tolerant mushroom spawn is inoculated. The mushroom is then cultured and growing in the temperature, humidity, and CO2 controlled environment. During the cultivation and growing process of the mushroom, microcystins are decomposed into non-toxic organic or inorganic compounds by diverse bacteria or various enzymes of the mushroom strains. Various enzymes of the mushroom strains decompose organics of the mixed organic waste and produce nutritious and antibiotic mushrooms. Cultured biomass compost after mushroom harvest can be used for organic fertilizer, functional bio-feed, and RE-100 biomass renewable energy source. In this eco-friendly organic waste recycling process, no toxic material, wastewater, nor sludge is generated; thus, sustainable with the circular economy.

Keywords: microalgae, microcystin, food waste, salt-tolerant mushroom strains, sustainability, circular economy

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Authors: M. Schapira, S. Françoise, F. Maheux, O. Pierre-Duplessix, E. Rabiller, B. Simon, R. Le Gendre

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Pico- and nano-phytoplankton are abundant and ecologically critical components of the autotrophic communities in the pelagic realm. While the role of physical forcing related to tidal cycle, water mass intrusion, nutrient availability, mixing and stratification on microphytoplankton blooms have been widely investigated, these are often overlooked for pico- and nano-phytoplankton especially in estuarine waters. This study investigates changes in abundances and community composition of pico- and nano-phytoplankton under different estuarine tidal conditions in the mouth of the Seine River in relation to nutrient availability, water column stratification and spatially localized currents. Samples were collected each day at high tide, over spring tide to neap tide cycle, from 21 stations homogeneously distributed in the Seine river month in May 2011. Vertical profiles of temperature, salinity and fluorescence were realized at each sampling station. Sub-surface water samples (i.e. 1 m depth) were collected for nutrients (i.e. N, P and Si), phytoplankton biomass (i.e. Chl a) and pico- and nano-phytoplankton enumeration and identification. Pico- and nano-phytoplankton populations were identified and quantified using flow cytometry. Total abundances tend to decrease from spring tide to neap tide. Samples were characterized by high abundances of Synechococcus and Cryptophyceae. The composition of the pico- and nano-phytoplankton varied greatly under the different estuarine tidal conditions. Moreover, at the scale of the river mouth, the pico- and nano-phytoplankton population exhibited patchy distribution patterns that were closely controlled by water mass intrusion from the Sea, freshwater inputs from the Seine River and the geomorphology of the river mouth. This study highlights the importance of physical forcing to the community composition of pico- and nano-phytoplankton that may be critical for the structure of the pelagic food webs in estuarine and adjacent coastal seas.

Keywords: nanophytoplancton, picophytoplankton, physical forcing, river mouth, tidal cycle

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Authors: Liaquat Ahmad, Muhammad Aslam, Muhammad Azam

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In this article, we propose a control chart based on repetitive group sampling scheme for the location parameter. This charting scheme is based on the regression estimator; an estimator that capitalize the relationship between the variables of interest to provide more sensitive control than the commonly used individual variables. The control limit coefficients have been estimated for different sample sizes for less and highly correlated variables. The monitoring of the production process is constructed by adopting the procedure of the Shewhart’s x-bar control chart. Its performance is verified by the average run length calculations when the shift occurs in the average value of the estimator. It has been observed that the less correlated variables have rapid false alarm rate.

Keywords: average run length, control charts, process shift, regression estimators, repetitive group sampling

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Authors: V. Vargas-Alejo, L. E. Montero-Moguel

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Understanding the concept of function has been important in mathematics education for many years. In this study, the models built by a group of five business administration and accounting undergraduate students when carrying out a population growth activity are analyzed. The theoretical framework is the Models and Modeling Perspective. The results show how the students included tables, graphics, and algebraic representations in their models. Using technology was useful to interpret, describe, and predict the situation. The first model, the students built to describe the situation, was linear. After that, they modified and refined their ways of thinking; finally, they created exponential growth. Modeling the activity was useful to deep on mathematical concepts such as covariation, rate of change, and exponential function also to differentiate between linear and exponential growth.

Keywords: covariation reasoning, exponential function, modeling, representations

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Authors: Zahid Ali Ghazi

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Supercapacitors (SCs) have emerged as auspicious energy storage devices because of their fast charge-discharge characteristics and high power densities. In the current study, a simple approach is used to coat activated carbon (AC) with a thin layer of nickel (Ni) by an electroless deposition process to enhance the electrochemical performance of the SC. The synergistic combination of large surface area and high electrical conductivity of the AC, as well as the pseudocapacitive behavior of the metallic Ni, has shown great potential to overcome the limitations of traditional SC materials. First, the materials were characterized using X-ray diffraction (XRD) for crystallography, scanning electron microscopy (SEM) for surface morphology and energy dispersion X-ray (EDX) for elemental analysis. The electrochemical performance of the nickel-coated activated carbon (Ni-AC) is systematically evaluated through various techniques, including galvanostatic charge-discharge (GCD), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The GCD results revealed that Ni/AC has a higher specific capacitance (1559 F/g) than bare AC (222 F/g) at 1 A/g current density in a 2 M KOH electrolyte. Even at a higher current density of 20 A/g, the Ni/AC showed a high capacitance of 944 F/g as compared to 77 F/g by AC. The specific capacitance (1318 F/g) calculated from CV measurements for Ni-AC at 10mV/sec was in close agreement with GCD data. Furthermore, the bare AC exhibited a low energy of 15 Wh/kg at a power density of 356 W/kg whereas, an energy density of 111 Wh/kg at a power density of 360 W/kg was achieved by Ni/AC-850 electrode and demonstrated a long life cycle with 94% capacitance retention over 50000 charge/discharge cycles at 10 A/g. In addition, the EIS study disclosed that the Rs and Rct values of Ni/AC electrodes were much lower than those of bare AC. The superior performance of Ni/AC is mainly attributed to the presence of excessive redox active sites, large electroactive surface area and corrosive resistance properties of Ni. We believe that this study will provide new insights into the controlled coating of ACs and other porous materials with metals for developing high-performance SCs and other energy storage devices.

Keywords: supercapacitor, cyclic voltammetry, coating, energy density, activated carbon

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Authors: Trishita Ray, Ashok Perka, Arnab Karani, M. Shome, Saurabh Kundu

Abstract:

Line pipe steels are used for long distance transportation of crude oil and gas under extreme environmental conditions. Welding is necessary to lay large scale pipelines. Coarse Grain Heat Affected Zone (CGHAZ) of a welded joint exhibits worst toughness because of excessive grain growth and brittle microstructures like bainite and martensite, leading to early failure. Therefore, it is necessary to investigate microstructures and properties of the CGHAZ for different welding heat inputs. In the present study, CGHAZ for two heat inputs of 10 kJ/cm and 50 kJ/cm were simulated in Gleeble 3800, and the microstructures were investigated in detail by means of Scanning Electron Microscopy (SEM) and Electron Backscattered Diffraction (EBSD). Charpy Impact Tests were also done to evaluate the impact properties. High heat input was characterized with very low toughness and massive prior austenite grains. With the crystallographic information from EBSD, the area of a single prior austenite grain was traced out for both the welding conditions. Analysis of the prior austenite grains showed the formation of high angle boundaries between the crystallographic packets. Effect of these packet boundaries on secondary cleavage crack propagation was discussed. It was observed that in the low heat input condition, formation of finer packets with a criss-cross morphology inside prior austenite grains was effective in crack arrest whereas, in the high heat input condition, formation of larger packets with higher volume of low angle boundaries failed to resist crack propagation resulting in a brittle fracture. Thus, the characteristics in a crystallographic packet and impact properties are related and should be controlled to obtain optimum properties.

Keywords: coarse grain heat affected zone, crystallographic packet, toughness, line pipe steel

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Authors: Sanchita B. Sarma, M. P. Nath

Abstract:

Adequate analgesia following caesarean section decreases morbidity, hastens ambulation, improves patient outcome and facilitates care of the newborn. Intrathecal magnesium, an NMDA antagonist, has been shown to prolong analgesia without significant side effects in healthy parturients. The aim of this study was to evaluate the onset and duration of sensory and motor block, hemodynamic effect, postoperative analgesia, and adverse effects of magnesium or fentanyl given intrathecally with hyperbaric 0.5% bupivacaine in patients with mild preeclampsia undergoing caesarean section. Sixty women with mild preeclampsia undergoing elective caesarean section were included in a prospective, double blind, controlled trial. Patients were randomly assigned to receive spinal anesthesia with 2 mL 0.5% hyperbaric bupivacaine with 12.5 µg fentanyl (group F) or 0.1 ml of 50% magnesium sulphate (50 mg) (group M) with 0.15ml preservative free distilled water. Onset, duration and recovery of sensory and motor block, time to maximum sensory block, duration of spinal anaesthesia and postoperative analgesic requirements were studied. Statistical comparison was carried out using the Chi-square or Fisher’s exact tests and Independent Student’s t-test where appropriate. The onset of both sensory and motor block was slower in the magnesium group. The duration of spinal anaesthesia (246 vs. 284) and motor block (186.3 vs. 210) were significantly longer in the magnesium group. Total analgesic top up requirement was less in group M. Hemodynamic parameters were similar in both the groups. Intrathecal magnesium caused minimal side effects. Since Fentanyl and other opioid congeners are not available throughout the country easily, magnesium with its easy availability and less side effect profile can be a cost effective alternative to fentanyl in managing pregnancy induced hypertension (PIH) patients given along with Bupivacaine intrathecally in caesarean section.

Keywords: analgesia, magnesium, pre eclampsia, spinal anaesthesia

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Authors: Damiaa Saad Khudor

Abstract:

The paper describes an investigation for the thermal design of a fluidized bed cooler and prediction of heat transfer rate among the media categories. It is devoted to the thermal design of such equipment and their application in the industrial fields. It outlines the strategy for the fluidization heat transfer mode and its implementation in industry. The thermal design for fluidized bed cooler is used to furnish a complete design for a fluidized bed cooler of Sodium Bicarbonate. The total thermal load distribution between the air-solid and water-solid along the cooler is calculated according to the thermal equilibrium. The step by step technique was used to accomplish the thermal design of the fluidized bed cooler. It predicts the load, air, solid and water temperature along the trough. The thermal design for fluidized bed cooler revealed to the installation of a heat exchanger consists of (65) horizontal tubes with (33.4) mm diameter and (4) m length inside the bed trough.

Keywords: fluidization, powder technology, thermal design, heat exchangers

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Authors: Bongmun Kang, Kagnari Yamakawa, Yoshihisa Hagihara, Yuji Ito, Michimasa Kishimoto, Yoichi Kumada

Abstract:

The PMMA-tag was genetically fused with the C-terminal region of VHH molecules. This antibody, VHH, is known as a single-chain domain, which is devoid of light chains. The PMMA-tag, which could affect the isoelectric point (pI) changeable with a charge of amino acid in VHHs were closely related to the solubility of VHH molecules during refolding. The genetic fusion of PMMA-tag to C-terminal region of VHHs significantly affects the recovery of their soluble protein during refolding by 50 mM TAPS at pH 8.5. It could be refolded with a recovery of more than 95% by dialysis at pH 8.5. A marked difference in the antigen-binding activities in the adsorption state was significantly high in VHH-PM compared to the wild type of VHH. There are approximately 8-fold differences in the antigen-binding activities in the adsorption state between VHH-PM and VHH.

Keywords: VHH, PMMA-tag, isoelectric point, pH, Solubility, refolding, immobilization, ELISA

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Authors: Akram Abi, Clarissa Müller, Hans-Joachim Jördening

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Laminaribiose is a beta-1,3-glycoside which is used in the medical field for the treatment of dermatitis and also can be used as a building block for new pharmaceutics. The conventional process of laminaribiose production is the uneconomical process of hydrolysis of laminarin extracted from natural polysaccharides of plant origin. A more economical approach however is attainable by enzymatically synthesis of laminaribiose via a reverse phosphorylase reaction catalyzed by laminaribiose phosphorylase (LP) from Euglena gracilis. Different cultivation methods of Euglena gracilis and the effect on LP production have been investigated. Buffered/unbuffered heterotrophic and mixotrophic cultivations of Euglena gracilis has been carried out. Changes of biomass and LP production, glucose level and pH, cell count and shape has been monitored in the course of time. The results obtained from experiments each in three repetitions, show that in the heterotrophic cultivation of Euglena gracilis not only more biomass is produced compared to mixotrophic cultivation, but also higher specific protein concentration is achieved. Furthermore, the LP activity test showed that the protein extracted from heterotrophically cultured cells has a higher LP activity. It was also observed that the cells develop in a distinctive different shape between these two cultures and have different length to width ratios. Taking the heterotrophic culture as the more efficient cultivation method in LP production, another comparative experiment between buffered and unbuffered heterothrophic culture was carried out that showed the unbuffered culture has advantages over the other one in respect of both LP production and resulting activity. A hetrotrophic cultivation of Euglena gracilis in a 5L bioreactor with controlled operating conditions showed a distinctive improvement of all the aspects of culture compared to the shaking flask cultivations. Biomass production was improved from 5 to more than 8 g/l (dry weight) which resulted in a specific protein concentration of 45 g/l in the heterotrophic cultivation in the bioreactor. In further attempts to improve LP production, different purification methods were tested and each method was checks through an activity assay. A laminaribiose yield of 35% was achieved which was by far the highest amount amongst different methods tested.

Keywords: euglena gracilis, heterotrophic culture, laminaribiose production, mixotrophic culture

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Authors: Mlk. Khouadjia, B. Mezghiche

Abstract:

The environment protection has led to a growing interest in the use of crushed sand, which is not correctly exploited due to the high rate of fine particles that it contains and which affect concrete properties. This study will examine the variation of the compressive strength of concrete with several local areas of sand exposed to freeze-thaw cycles and chemical solutions. The experiments have been realized on crushed, river, and dune sands. We use software (MATLAB) to find the coefficient of particle shape. Finally, we have found a relationship between the reference concrete without modification and concrete modified with river and dune sands to predict the variations of resistance after curing in different environments. The results showed that the behavior of concrete is different according to the types of sand and the environment of exposition.

Keywords: crushed sand, compressive strength, freeze-thaw, MATLAB, dune sand, river sand

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Authors: Shabnam Dadparvar, Laijin Shen

Abstract:

After a period of conflict between Russia and the West, new signs of confrontation between the United States and China are observed. China, as the most populous country in the world with a high rate of economic growth, neither stands the hegemonic power of the United States nor has the intention of direct confrontation with it. By raising the costs of the United States’ leadership at the international level, China seeks to find a better status without direct confrontation with the US. Meanwhile, the Shanghai Cooperation Organization (SCO), as a soft balancing strategy against the hegemony of the United States is used as a tool to reach this goal. The authors by using a descriptive-analytical method try to explain the policies of China and the United States on Shanghai Cooperation Organization as well as confrontation between these two countries within the framework of 'balance of soft power theory'.

Keywords: balance of soft power, Central Asia, Shanghai cooperation organization, terrorism

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Authors: Ramzi Bekri Umer

Abstract:

Aim: This study attempts to investigate the causes and difficulties with women’s incarceration as well as threat for their reintegration after release from prison with emphasis on the correctional facility of Haramaya city. Method and Methodology: Both quantitative and qualitative research methods were employed in this study; key informant interviews and participant observation were utilized to gather qualitative data, while crosssectional and descriptive research designs were used to gather quantitative data. Findings: This study shows that the women's incarceration was caused by their family histories, genderbased violence, illiteracy, and socioeconomic issues. The principal charges made against the female culprits were theft, vandalism, murder, and moral perversion. A poor quality of life in prison, concerns about family dissolution, emotional instability, financial difficulties, and a lack of spirituality were the main causes of unhappiness for the women behind bars, while social stigma, mistrust, and retaliation fears were the main obstacles to the women's ability to reintegrate into their families and communities. Theoretical Importance: This study involves incarcerated women at correctional center of Haramaya who committed various types of crimes. The local government sectors and non-governmental organization will gain from the study in order to create workable plans to reduce women's criminality and the growing number of female lawbreakers. Local communities and other governmental and nongovernmental partners will be able to support gender equality initiatives that seek to eradicate gender-based violence and discrimination, which worsen the criminality of women. Data Collection and Analysis Procedures: The quantitative and qualitative data were collected prospectively from a sample of 100 women prisoners. Quantitative data were analyzed using descriptive statistics, whereas, thematic analysis, were used for qualitative data. Question Answered: 1. What are the main causes women’s imprisonment in Haramaya city correctional facility. 2. What are the main obstacles of the women's ability to reintegrate into their families and communities after released from incarceration. Conclusion: The study concludes that incarcerated women experience a tremendous impact on their daily life. It highlights the importance of addressing factors such as family backgrounds, gender-based violence, illiteracy and socio-economic problem to decrease the number of women imprisonment. Detention environment, fear for family breakup, financial hardship and deprivation of spiritual life are the major sources of distress among the incarcerated women.

Keywords: Ethiopia, women prisoner, incarceration, reintegration

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