Search results for: size control

Authors: Mihir Hota, Namita Jena, S. N. Sahu

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LEEH (L-cysteine ethyl ester hydrochloride) capped CdS semiconductor nanocrystals are grown at 800C using a simple chemical route. Photoluminescence (PL), Optical absorption (UV) and Transmission Electron Microscopy (TEM) have been carried out to evaluate the structural and optical properties of the nanocrystal. Optical absorption studies have been carried out to optimize the sample. XRD and TEM analysis shows that the nanocrystal belongs to FCC structure having average size of 3nm while a bandgap of 2.84eV is estimated from Photoluminescence analysis. The nanocrystal emits bluish light when excited with 355nm LASER.

Keywords: cadmium sulphide, nanostructures, luminescence, optical properties

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Authors: Alaa Fezai, Anuj Sharma, Wolfgang Mueller-Hirsch, André Zimmermann

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Viscoelastic materials have been widely used in the automotive industry over the last few decades with different functionalities. Besides their main application as a simple and efficient surface damping treatment, they may ensure optimal operating conditions for on-board electronics as thermal interface or sealing layers. The dynamic behavior of viscoelastic materials is generally dependent on many environmental factors, the most important being temperature and strain rate or frequency. Prior to the reliability analysis of systems including viscoelastic layers, it is, therefore, crucial to accurately predict the dynamic and lifetime behavior of these materials. This includes the identification of the dynamic material parameters under critical temperature and frequency conditions along with a precise damage localization and identification methodology. The goal of this work is twofold. The first part aims at applying an inverse viscoelastic material-characterization approach for a wide frequency range and under different temperature conditions. For this sake, dynamic measurements are carried on a single lap joint specimen using an electrodynamic shaker and an environmental chamber. The specimen consists of aluminum beams assembled to adapter plates through a viscoelastic adhesive layer. The experimental setup is reproduced in finite element (FE) simulations, and frequency response functions (FRF) are calculated. The parameters of both the generalized Maxwell model and the fractional derivatives model are identified through an optimization algorithm minimizing the difference between the simulated and the measured FRFs. The second goal of the current work is to guarantee an on-line detection of the damage, i.e., delamination in the viscoelastic bonding of the described specimen during frequency monitored end-of-life testing. For this purpose, an inverse technique, which determines the damage location and size based on the modal frequency shift and on the change of the mode shapes, is presented. This includes a preliminary FE model-based study correlating the delamination location and size to the change in the modal parameters and a subsequent experimental validation achieved through dynamic measurements of specimen with different, pre-generated crack scenarios and comparing it to the virgin specimen. The main advantage of the inverse characterization approach presented in the first part resides in the ability of adequately identifying the material damping and stiffness behavior of soft viscoelastic materials over a wide frequency range and under critical temperature conditions. Classic forward characterization techniques such as dynamic mechanical analysis are usually linked to limitations under critical temperature and frequency conditions due to the material behavior of soft viscoelastic materials. Furthermore, the inverse damage detection described in the second part guarantees an accurate prediction of not only the damage size but also its location using a simple test setup and outlines; therefore, the significance of inverse numerical-experimental approaches in predicting the dynamic behavior of soft bonding layers applied in automotive electronics.

Keywords: damage detection, dynamic characterization, inverse approaches, vibration testing, viscoelastic layers

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Authors: Warakorn Supwirapakorn

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The purpose of this research was to study the effects of choice theory in group counseling on coping strategies of students. The sample consisted of 16 students at a boarding school, who had the lowest score on the coping strategies. The sample was divided into two groups by random assignment and then were assigned into the experimental group and the control group, with eight members each. The instruments were the Adolescent Coping Scale and choice theory group counseling program. The data collection procedure was divided into three phases: The pre-test, the post-test, and the follow-up. The data were analyzed by repeated measure analysis of variance: One between-subjects and one within-subjects. The results revealed that the interaction between the methods and the duration of the experiment was found statistically significant at 0.05 level. The students in the experimental group demonstrated significantly higher at 0.05 level on coping strategies score in both the post-test and the follow-up than in the pre-test and the control group. No significant difference was found on coping strategies during the post-test phase and the follow-up phase of the experimental group.

Keywords: coping strategies, choice theory, group counseling, boarding school

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Authors: Mohamed Ahmed Tony, Mohamed Hamoud

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The present study was conducted to determine the effect of commercially coated slow-release sodium butyrate (CM3000®) as a feed additive on zootechnical performance, immune status and Clostridium perfringens severity after experimental infection. Three hundred 1-d-old broiler chicks (Cobb 500) were randomly distributed into 3 treatment groups (4 replicates each) using 25 chicks per replicate on floor pens. Control (C) birds were offered non-supplemented basal diets. Treatments 1 and 2 (T1 and T2) were fed diets containing CM3000® at 300 and 500 g/ton feed, respectively, during the entire experimental period (35 days). Feed and water were offered ad-libitum. Feed consumption and body weight were recorded weekly to calculate body weight gain and feed conversion. Blood samples were collected to evaluate the immune status of the birds against Newcastle disease vaccines using HI test. At the end of the experimental period, 20 birds were chosen randomly from each group (5 birds from each pen) to compare carcass yield. At day 16 of age 20 birds from each group (5 birds/replicate) were bacteriologically examined and proved to be free from Clostridium perfringens. The isolated birds were challenged orally with 1 ml buffer containing 106 CFU/ml Clostridium perfringens local isolate and prepared from necrotic enteritis (NE) diseased farms. Birds were observed on a regular basis daily for any signs of NE. Birds that died in the challenged group were necropsied to determine the cause of death. On day 28 of age, the surviving chickens were killed by cervical dislocation and necropsied immediately. Intestinal tracts were removed and intestinal lesions were scored. Tissue samples of the duodenum, jejunum, ileum and cecum for histopathological examination were collected. All collected data were statistically analyzed using IBM SPSS® version 19 software for personal computers. Means were compared by one-way ANOVA (P<0.05) followed by the Duncan Post Hoc test. The results revealed that body weight gain was significantly (P<0.05) improved in chicks fed on both doses of CM3000® compared to the control one. Final body weight gain in T1 and T2 were 2064.94 and 2141.37 g/bird, respectively, while in the control group, the weight gain showed 1952.78 g/bird. In addition, supplementation of diets with CM3000® increased significantly feed intake (P<0.05). Total feed intake in T1 and T2 were 3186.32 and 3273.29 g/bird, respectively; however, feed intake in the control group recorded 3081.95 g/bird. The best feed conversion was recorded in T2 group (1.53). Feed conversion in the control and T1 groups were 1.58 and 1.54, respectively. Dressing percentage, liver weights and the other carcasses yields were not different between treatments. The butyrate significantly enhanced immune responses measured against Newcastle disease vaccines. Sodium butyrate significantly reduced NE lesions and healthy improved the intestinal tissues in the samples collected from T1 and T2-challenged chickens versus those collected from the control group. In conclusion, exogenous administration of slow-release butyrate (CM3000®) is capable of improving performance, enhancing immunity and NE disease resistance in broiler chickens.

Keywords: sodium butyrate, broiler chicken, zootechnical performance, immunity, necrotic enteritis

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Authors: Gadisa Demie, Mesele Negash, Zerihun Asrat, Lojka Bohdan

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Deforestation and forest degradation in the tropics have led to significant carbon (C) emissions. Agroforestry (AF) is a suitable land-use option for tackling such declines in ecosystem services, including climate change mitigation. However, it is unclear how biomass models, AF practices, and socio-ecological factors determine these roles, which hinders the implementation of climate change mitigation initiatives. This study aimed to estimate the ecosystem C stocks of the studied AF practices in relation to socio-ecological variables in central Ethiopia. Out of 243 AF farms inventoried, 108 were chosen at random from three AF practices to estimate their biomass and soil organic carbon. A total of 432 soil samples were collected from 0–30 and 30–60 cm soil depths; 216 samples were taken for each soil organic carbon fraction (%C) and bulk density computation. The study found that the currently developed allometric equations were the most accurate to estimate biomass C for trees growing in the landscape when compared to previous models. The study found higher overall biomass C in woodlots (165.62 Mg ha-¹) than in homegardens (134.07 Mg ha-¹) and parklands (19.98 Mg ha-¹). Conversely, overall, SOC was higher for homegardens (143.88 Mg ha-¹), but lower for parklands (53.42 Mg ha-¹). The ecosystem C stock was comparable between homegardens (277.95 Mg ha-¹) and woodlots (275.44 Mg ha-¹). The study found that elevation, wealthy levels, AF farm age, and size have a positive and significant (P < 0.05) effect on overall biomass and ecosystem C stocks but non-significant with slope (P > 0.05). Similarly, SOC increased with increasing elevation, AF farm age, and wealthy status but decreased with slope and non-significant with AF farm size. The study also showed that species diversity had a positive (P <0.05) effect on overall biomass C stocks in homegardens. The overall study highlights that AF practices have a great potential to lock up more carbon in biomass and soils; however, these potentials were determined by socioecological variables. Thus, these factors should be considered in management strategies that preserve trees in agricultural landscapes in order to mitigate climate change and support the livelihoods of farmers.

Keywords: agricultural landscape, biomass, climate change, soil organic carbon

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Authors: Amer Elgerwi, Abdelrazzag El-Magdoub, Abubakr El-Mahmoudy

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There are many bacterial infections affecting sheep that necessitates antibiotic intervention. Amoxicillin is among commonly used antibiotics in such case for its broad spectrum of activity. However, the side alterations in blood and organ function that may be associated during or after treatment are questionable. Therefore, the aim of the present study was to assess the possible alterations in blood parameters and organ function bio markers of sheep that may occur following intramuscular injection of amoxicillin. Amoxicillin has been administered intramuscularly to 10 sheep at a dosage regimen of 7 mg/kg of body weight for 5 successive days. Two types of blood samples (with and without anticoagulant) were collected from the jugular vein pre- and post-administration of the drug. Amoxicillin significantly (P < 0.001) increased total leukocyte count and (P < 0.05) absolute eosinophilic count when compared with those of the control samples. Aspartate aminotransferase, alkaline phosphatase and cholesterol were significantly (P < 0.05) higher than the corresponding control values. In addition, amoxicillin significantly (P < 0.05) increased blood urea nitrogen and creatinine but decreased phosphorus level when compared with those of prior-administration samples. These data may indicate that although the side changes caused by amoxicillin are minor in sheep, yet the liver and kidney functions should be monitored during its usage in therapy and it should be used with care for treatment of sheep with renal and/or hepatic impairments.

Keywords: amoxicillin, biogram, haemogram, sheep

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Authors: Yazan S. Khaled, Shazana Shamsuddin, Jim Tiernan, Mike McPherson, Thomas Hughes, Paul Millner, David G. Jayne

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Introduction: There is a need for real-time imaging of colorectal cancer (CRC) to allow tailored surgery to the disease stage. Fluorescence guided laparoscopic imaging of primary colorectal cancer and the draining lymphatics would potentially bring stratified surgery into clinical practice and realign future CRC management to the needs of patients. Fluorescent nanoparticles can offer many advantages in terms of intra-operative imaging and therapy (theranostic) in comparison with traditional soluble reagents. Nanoparticles can be functionalised with diverse reagents and then targeted to the correct tissue using an antibody or Affimer (artificial binding protein). We aimed to develop and test fluorescent silica nanoparticles and targeted against CRC using an anti-carcinoembryonic antigen (CEA) Affimer (Aff). Methods: Anti-CEA and control Myoglobin Affimer binders were subcloned into the expressing vector pET11 followed by transformation into BL21 Star™ (DE3) E.coli. The expression of Affimer binders was induced using 0.1 mM isopropyl β-D-1-thiogalactopyranoside (IPTG). Cells were harvested, lysed and purified using nickle chelating affinity chromatography. The photosensitiser Foslip (soluble analogue of 5,10,15,20-Tetra(m-hydroxyphenyl) chlorin) was incorporated into the core of silica nanoparticles using water-in-oil microemulsion technique. Anti-CEA or control Affs were conjugated to silica nanoparticles surface using sulfosuccinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (sulfo SMCC) chemical linker. Binding of CEA-Aff or control nanoparticles to colorectal cancer cells (LoVo, LS174T and HC116) was quantified in vitro using confocal microscopy. Results: The molecular weights of the obtained band of Affimers were ~12.5KDa while the diameter of functionalised silica nanoparticles was ~80nm. CEA-Affimer targeted nanoparticles demonstrated 9.4, 5.8 and 2.5 fold greater fluorescence than control in, LoVo, LS174T and HCT116 cells respectively (p < 0.002) for the single slice analysis. A similar pattern of successful CEA-targeted fluorescence was observed in the maximum image projection analysis, with CEA-targeted nanoparticles demonstrating 4.1, 2.9 and 2.4 fold greater fluorescence than control particles in LoVo, LS174T, and HCT116 cells respectively (p < 0.0002). There was no significant difference in fluorescence for CEA-Affimer vs. CEA-Antibody targeted nanoparticles. Conclusion: We are the first to demonstrate that Foslip-doped silica nanoparticles conjugated to anti-CEA Affimers via SMCC allowed tumour cell-specific fluorescent targeting in vitro, and had shown sufficient promise to justify testing in an animal model of colorectal cancer. CEA-Affimer appears to be a suitable targeting molecule to replace CEA-Antibody. Targeted silica nanoparticles loaded with Foslip photosensitiser is now being optimised to drive photodynamic killing, via reactive oxygen generation.

Keywords: colorectal cancer, silica nanoparticles, Affimers, antibodies, imaging

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Authors: Siamak Yaghoubi, Vahideh Rashtchi, Marzieh Khezri, Hamid Kayalha, Monadi Hamidfar

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Background and objectives: Effective postoperative pain management in abdominal surgeries, which are painful procedures, plays an important role in reducing postoperative complications and increasing patient’s satisfaction. There are many techniques for pain control, one of which is Patient-Controlled Analgesia (PCA). The aim of this study was to compare the analgesic effects of morphine, paracetamol and ketorolac in the patients undergoing open cholecystectomy, using PCA method. Material and Methods: This randomized controlled trial was performed on 330 ASA (American Society of Anesthesiology) I-II patients ( three equal groups, n=110) who were scheduled for elective open cholecystectomy in Shahid Rjaee hospital of Qazvin, Iran from August 2013 until September 2015. All patients were managed by general anesthesia with TIVA (Total Intra Venous Anesthesia) technique. The control group received morphine with maximum dose of 0.02mg/kg/h, the paracetamol group received paracetamol with maximum dose of 1mg/kg/h, and the ketorolac group received ketorolac with maximum daily dose of 60mg using IV-PCA method. The parameters of pain, nausea, hemodynamic variables (BP and HR), pruritus, arterial oxygen desaturation, patient’s satisfaction and pain score were measured every two hours for 8 hours following operation in all groups. Results: There were no significant differences in demographic data between the three groups. there was a statistically significant difference with regard to the mean pain score at all times between morphine and paracetamol, morphine and ketorolac, and paracetamol and ketorolac groups (P<0.001). Results indicated a reduction with time in the mean level of postoperative pain in all three groups. At all times the mean level of pain in ketorolac group was less than that in the other two groups (p<0.001). Conclusion: According to the results of this study ketorolac is more effective than morphine and paracetamol in postoperative pain control in the patients undergoing open cholecystectomy, using PCA method.

Keywords: analgesia, cholecystectomy, ketorolac, morphine, paracetamol

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Authors: Nnennaya Samuel Okoro

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An experiment was conducted to determine the growth performance, blood parameters and reproductive characteristics of 8-week old male weaner rabbits fed 20% boiled pigeon pea seed meal (PPSM). The study lasted for 16 weeks. Results showed that haematological parameters of the two groups of rabbit bucks were not significantly affected (P>0.05) by the treatment, meaning that the PPSM was adequate for maintaining the blood parameters at the normal levels. The 20% boiled PPSM significantly affected (P<0.05) serum Alanine Aminotransferase (ALT) (67.72±2.5 I.U/I) more than the ALT (57.50±2.02 I.U/I) of the control, which is an indication of liver problem. The globulin level (3.00 ± 0.23 g/d) of the 20% boiled PPSM group was significantly higher than that of the control (2.60±0.06 g/dl), indicating that the test diet did not alter protein metabolism in the rabbits. Boiled pigeon pea seed meal supported organ weight and testicular development in rabbit bucks, suggesting that boiling reduced the level of the anti-nutritional factors in pigeon pea seed meal. Thus, 20% boiled pigeon pea can be included in diets of rabbits without adverse effect on blood parameters and internal organs characteristics.

Keywords: haematology, internal organs, pigeon pea, rabbits, serum biochemistry

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Authors: Kenza Aida Amara, Bachir Djebbar

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We treat the two-dimensional bin packing problem which involves packing a given set of rectangles into a minimum number of larger identical rectangles called bins. This combinatorial problem is NP-hard. We propose a pretreatment for the oriented version of the problem that allows the valorization of the lost areas in the bins and the reduction of the size problem. A heuristic method based on the strategy first-fit adapted to this problem is presented. We present an approach of resolution by bee colony optimization. Computational results express a comparison of the number of bins used with and without pretreatment.

Keywords: bee colony optimization, bin packing, heuristic algorithm, pretreatment

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Authors: Itulelo Matiyabu Imaja, Patrick Ndayizigamiye, Manoj Maharaj

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There are many catalysts of corruption. These include amongst others, lack of effective control measures to deter or detect corrupt behaviour. Literature suggests that ICT could assist in curbing corruption through the implementation of automated systems, citizens engagement through e-government and online media to name a few. In the Democratic Republic of Congo, lack of transparency and accountability in public funds collection and allocation contribute to corruption in funds mismanagement. Using the accountability theory and available literature, this paper analyses how Democratic Republic of Congo (DRC) institutions could be strengthened through ICT in order to deter instances of corruption. Findings reveal that DRC lacks reliable control, monitoring and evaluation mechanisms that could identify potentially corrupt behavior. In addition, citizens and civil society organizations who are meant to hold the institutions accountable are not given secure platform to express their views and potentially flag any corrupt behavior. Hence, the paper presents a preliminary conceptual framework that depicts how ICT could be used to strengthen current institutions to potentially deter corrupt behavior in public funds management in Congo.

Keywords: corruption, ICT adoption, transparency, DR Congo

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Authors: Ramandeep Kaur, Kamaljit Kaur, Preeti Ahluwalia, Poonam A. Sachdev

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Bread is an ideal vehicle to impart bioactive compounds to the consumers in a convenient manner. This study evaluated bread enriched with red sweet pepper powder (RSP) at 2, 4, 6, 8, 10% and compared to control bread (without RSP). The bread crumbs were assayed for bioactive, physical, nutritional, textural, color, and sensory properties. Bread supplemented with RSP improved its color, nutritional, and bioactive properties. The low moisture content and increased hardness were observed at higher levels of RSP. Color intensity (expressed as L*, a*, b* values) of bread with 2 and 4% RSP were lower than those of high levels, and the same trend was observed for protein, fibre and ash content of bread. Significant (p < 0.05) increases were recorded for bioactive compounds such as total phenols (0.145 to 235 mg GAE/g), antioxidant activity (56% to 78%) and flavonoids (0.112 to 0.379 mg/g) as the level of powder increased. Bread enriched with 8% RSP showed improved sensory profile as compared to control, whereas a further increase in RSP decreased the sensory and textural properties. Thus, RSP act as a natural colorant and functional food that enhanced the functional and nutritional properties of bread and can be used to customize bread for specific health needs.

Keywords: breads, bioactive compounds, red sweet pepper powder, sensory scores

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Authors: Filip Rusak, Yulia Arzhaeva, Dadong Wang

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Machine learning based Computer-Aided Diagnosis (CAD) is gaining much popularity in medical imaging and diagnostic radiology. However, it requires a large amount of high quality and labeled training image datasets. The training images may come from different sources and be acquired from different radiography machines produced by different manufacturers, digital or digitized copies of film radiographs, with various sizes as well as different pixel intensity distributions. In this paper, a content-aware image augmentation method is presented to deal with these variations. The results of the proposed method have been validated graphically by plotting the removed and added seams of pixels on original images. Two different chest X-ray (CXR) datasets are used in the experiments. The CXRs in the datasets defer in size, some are digital CXRs while the others are digitized from analog CXR films. With the proposed content-aware augmentation method, the Seam Carving algorithm is employed to resize CXRs and the corresponding labels in the form of image masks, followed by histogram matching used to normalize the pixel intensities of digital radiography, based on the pixel intensity values of digitized radiographs. We implemented the algorithms, resized the well-known Montgomery dataset, to the size of the most frequently used Japanese Society of Radiological Technology (JSRT) dataset and normalized our digital CXRs for testing. This work resulted in the unified off-the-shelf CXR dataset composed of radiographs included in both, Montgomery and JSRT datasets. The experimental results show that even though the amount of augmentation is large, our algorithm can preserve the important information in lung fields, local structures, and global visual effect adequately. The proposed method can be used to augment training and testing image data sets so that the trained machine learning model can be used to process CXRs from various sources, and it can be potentially used broadly in any medical imaging applications.

Keywords: computer-aided diagnosis, image augmentation, lung segmentation, medical imaging, seam carving

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Authors: In-Lee Choi, Sung Mi Hong, Min Jae Jeong, Jun Pill Baek, Ho-Min Kang

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Gomchwi (Ligularia fischeri) is grown in the wetland of the deep mountains in Korea and East Asia and has properties that are, inflammation control, whitening, antimutagenic and antigenotoxic. Jangajji is a type of pickle in Korean fermented food which is made by pickling or marinating vegetables in a sauce, such as soy sauce, chili pepper paste, soybean paste, or diluted vinegar for a long period of time. Handaeri-gomchwi jangajii is generally packed a film that has very low or no gas permeability in the Korean domestic market, so packages have a risk of swelling or bursting as a result of internal gas generation during storage or sale This study was conducted to improve secure distribution of Handaeri-gomchwi (Ligularia fischeri var. spiciformis Nakai) Jangajji using laser ablation OTR (oxygen transmission rate) films. Handaeri-gomchwi cultivated in Yangu, Gangwon province, Republic of Korea (Ligularia fischeri var. spiciformis Nakai) was processed in to Jangajji using soy sauce. They were packed by different OTR films, and were stored for 90 days in 7℃(10,000 cc, 20,000 cc, 40,000 cc and 80,000 cc O2/m²• day • atm), 20 days in 20℃ (10,000 cc, 30,000 cc, 70,000 cc and 100,000 cc) and compared with the control film(PP film, 1,300cc). The fresh weight loss, carbon dioxide, oxygen, and ethylene concentrations of Handaeri–gomchwi packages were measured during storage. On the final day of storage, incidence rate of fungi, pH, salinity, firmness, and off-flavor were measured. The fresh weight loss rate of Handaeri–gomchwi was less than 2.0% in 10,000cc OTR films at two different storage periods and temperatures. At 80,000cc(7℃) and 100,000cc(20℃), carbon dioxide contents were 2.0% and 6.4% respectively, whereas the control treatment had the highest concentration. Which was 35%(20℃) and 15%(7℃) , that resulted the packages to swell during storage. The control treatment Showed the lowest oxygen concentration at 2.5% in 7℃ and 0.8% in 20℃. Packages in 7℃ (0.3-1.7μL/L) showed very lower ethylene concentration than in 20℃(10-25μL/L), they also had no significant relation. On the final storage day, fungi were found in every film at both temperatures, except the 10,000cc, as oxygen permeability increased so did the pH, while the salinity decreased. Firmness and off-flavor Showed the best results at 10,000cc in both temperatures best result at 10,000cc in both temperature. Following the results, 10,000cc film is the most reasonable treat in storing Handaeri–gomchwi. For it had a suitable oxygen transmission rate, which prevents billowing, and maintained good qualities in both temperatures.

Keywords: carbon dioxide, Korean pickle, marketable, oxygen

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Authors: Gebregziabher Brhane Berhe, Wei-Nien Su, Bing Joe Hwang

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A new lithium-ion battery is configured by coupling sulfurized carbon anode and high voltage LiNi₀.₅Mn₁.₅O₄ (LNMO) cathode. The anode is derived from sulfurized polyacrylonitrile (S-C(PAN)). Severe capacity fading usually becomes unavoidable due to the oxidative decomposition of solvents, primarily when a conventional carbonate electrolyte with 1 M lithium hexafluorophosphate (LiPF6) is employed. Fluoroethylene carbonate (FEC), ethyl methyl carbonate (EMC), and 1, 1, 2, 2-Tetrafluoroethyl-2, 2, 3, 3-tetrafluoropropyl ether (TTE) are formulated as the best electrolyte (3:2:5 in vol. ratio) for this new high-voltage lithium-ion battery to mitigate this capacity fading and improve the adaptability of the S-C(PAN) and LNMO. The discharge capacity of a full cell made with 1 M lithium hexafluorophosphate (LiPF6) in FEC/EMC/TTE (3:2:5) electrolyte reaches 688 mAh g⁻¹ at a rate of 2 C, while 19 mAh g⁻¹ for the control electrolyte. X-ray photoelectron spectroscopy (XPS) results confirm that the fluorinated electrolyte effectively stabilizes both surfaces of S-C(PAN) and LNMO in the full cell. Compared to the control electrolyte, the developed electrolyte enhances the cyclic stability and rate capability of both half cells (Li//S-C(PAN and Li//LiNi₀.₅Mn₁.₅O₄) and S-C(PAN)//LiNi₀.₅Mn₁.₅O₄ full cells.

Keywords: fluorinated electrolyte, high voltage, lithium-ion battery, polyacrylonitrile

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Authors: Monirah Alkathiry, Hanan Aljarwan

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Cloud computing is one of the most significant technologies that the world deals with, in different sectors with different purposes and capabilities. The cloud faces various challenges in securing data from unauthorized access or modification. Consequently, security risks and levels have greatly increased. Therefore, cloud service providers (CSPs) and users need secure mechanisms that ensure that data are kept secret and safe from any disclosures or exploits. For this reason, CSPs need a number of techniques and technologies to manage and secure access to the cloud services to achieve security goals, such as confidentiality, integrity, identity access management (IAM), etc. Therefore, this paper will review and explore various access controls implemented in a cloud environment that achieve different security purposes. The methodology followed in this survey was conducting an assessment, evaluation, and comparison between those access controls mechanisms and technologies based on different factors, such as the security goals it achieves, usability, and cost-effectiveness. This assessment resulted in the fact that the technology used in an access control affects the security goals it achieves as well as there is no one access control method that achieves all security goals. Consequently, such a comparison would help decision-makers to choose properly the access controls that meet their requirements.

Keywords: access controls, cloud computing, confidentiality, identity and access management

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Authors: Edwin Christmann, John Hicks

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This meta-analysis compared the mathematics achievement of students who received either traditional instruction or traditional instruction supplemented with computer-assisted instruction (CAI). From the 27 conclusions, an overall mean effect size of 0.236 was calculated, indicating that, on average, students receiving traditional instruction supplemented with CAI attained higher mathematics achievement than did 59.48 percent of those receiving traditional instruction per se.

Keywords: CAI, science, meta-analysis, traditional

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Authors: Tharntip Tawnie Chutikulrungsee, Oliver Kisalay Burmeister, Maumita Bhattacharya, Dragana Calic

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Sharing on social network sites (SNSs) has rapidly emerged as a new social norm and has become a global phenomenon. Billions of users reveal not only their own information (self disclosure) but also information about others (other-generated disclosure), resulting in a risk and a serious threat to either personal or informational privacy. Self-disclosure (SD) has been extensively researched in the literature, particularly regarding control of individual and existing privacy management. However, far too little attention has been paid to other-generated disclosure (OGD), especially by insiders. OGD has a strong influence on self-presentation, self-image, and electronic word of mouth (eWOM). Moreover, OGD is more credible and less likely manipulated than SD, but lacks privacy control and legal protection to some extent. This article examines OGD in depth, ranging from motivation to both online and offline impacts, based upon lived experiences from both ‘the disclosed’ and ‘the discloser’. Using purposive sampling, this phenomenological study involves an online survey and in-depth interviews. The findings report the influence of peer disclosure as well as users’ strategies to mitigate privacy issues. This article also calls attention to the challenge of OGD privacy and inadequacies in the law related to privacy protection in the digital domain.

Keywords: facebook, online privacy, other-generated disclosure, social networks sites (SNSs)

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Authors: Fangfang Wang, Tianjing Wang, Leyi Fu, Feng Yun, Ningning Xie, Jue Zhou, Fan Qu

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Background: Ferroptosis, a recently discovered form of programmed cell death characterized by iron-dependent lipid peroxidation, may be linked to polycystic ovary syndrome (PCOS). Diseases marked by iron overload have been correlated with ferroptosis. Coincidently, investigations have revealed anomalies in iron metabolism among women with PCOS; however, there were inconsistencies in the evidence. Objective and Rationale: This review aimed to comprehensively explore the potential relationship between ferroptosis and PCOS by investigating the differences in iron metabolism among women with PCOS in comparison to a control group. Additionally, a narrative synthesis was provided on the past research status regarding the association between PCOS and ferroptosis. Methods: A systematic search of the literature was performed using PubMed, Embase, Web of Science from inception up to December 2022. Search terms relating to assisted PCOS, ferroptosis, and iron metabolism were used. PRISMA guidance was followed. RevMan 5.4 was utilized for conducting the meta-analysis, wherein the investigated outcomes included iron status (ferritin, iron, transferrin saturation) and a systemic iron-regulatory hormone (hepcidin). A narrative synthesis was performed to explore the correlation between PCOS and ferroptosis. Results: In the meta-analysis comprising a total of 16 studies, significant differences in serum ferritin levels between the PCOS group and the control group were observed (15 studies, standardized mean difference (SMD): 0.41, 95% CI: 0.22 to 0.59, P<0.01). This indicates elevated serum ferritin levels in PCOS patients compared to women without PCOS. The transferrin saturation in PCOS patients was significantly higher than that in the control group (3 studies, mean difference (MD): 4.39, 95% CI: 1.67 to 7.11, P<0.01). Regarding serum iron (6 studies, SMD: 0.05, 95% CI: -0.24 to 0.33, P=0.75) and serum hepcidin (4 studies, SMD: -0.44, 95% CI: -1.41 to 0.52, P=0.37), no statistically significant differences were observed between the PCOS group and the control group. Other studies have found that ferroptosis is involved in the occurrence and development of PCOS, offering valuable insights for guiding potential treatment measures and prognosis evaluation of PCOS. In addition, ferroptosis is involved in the miscarriage of PCOS-like rats; thus, controlling ferroptosis might improve pregnancy outcomes in PCOS. Conclusions: The observation of a significant elevation in serum ferritin and transferrin saturation levels in women with PCOS may suggest an underlying disturbance in iron metabolism, potentially inducing the activation of ferroptosis. Further research is imperative to elucidate the underlying pathophysiology, providing insights for potential preventive measures and therapeutic strategies. Limitation: There are some limitations as follows: First, due to limited extractable information, we excluded purely abstract publications and non-English publications. Second, the majority of original articles were case-control studies, making it difficult to determine the causal relationship between iron metabolism abnormalities and the onset of PCOS. Third, there is substantial heterogeneity in the definition of PCOS.

Keywords: polycystic ovary syndrome, ferroptosis, iron metabolism, systematic review and meta-analysis

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Authors: Ali Babajanzade, Hossein Bozorgian

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Cognitive load plays an important role in learning in general and L2 listening comprehension in particular. This study is an attempt to investigate the effect of metacognitive strategy intervention through dialogic interaction (MSIDI) on L2 listeners’ cognitive load. A mixed-method design with 50 participants of male and female Iranian lower-intermediate learners between 20 to 25 years of age was used. An experimental group (n=25) received weekly interventions based on metacognitive strategy intervention through dialogic interaction for ten sessions. The second group, which was control (n=25), had the same listening samples with the regular procedure without a metacognitive intervention program in each session. The study used three different instruments: a) a modified version of the cognitive load questionnaire, b) digit span tests, and c) focused group interviews to investigate listeners’ level of cognitive load throughout the process. Results testified not only improvements in listening comprehension in MSIDI but a radical shift of cognitive load rate within this group. In other words, listeners experienced a lower level of cognitive load in MSIDI in comparison with their peers in the control group.

Keywords: cognitive load theory, human mental functioning, metacognitive theory, listening comprehension, sociocultural theory

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Authors: Neslihan Ozsoy Taskiran, Miray Dayioglu, Belgin Gunbey, Banu Yucel, Cigdem Takma, Unal Karik, Tugce Olgun, Levent Aydin

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A greater wax moth (Galleria mellonella L.), which is one of the most important pests after Varroa, plays a role in the transportation of many pathogens into the hive as well as damage to the honeycombs, and beekeepers suffer economically. Due to the risk that some of the methods against this pest may cause residue in bee products, and it can be harmful to the health of people who consume these products. Therefore, the most appropriate, most economical, and effective method should be applied in the moth control. For this purpose, in the first phase of the project (2017-2018), planned to be 2-stage in the Aegean Agricultural Research Institute in 2017-2020, the honeycombs, certified with good agricultural practice, were kept in a favorable condition for moths. Later, applications (Sulfur - B401 - Walnut (Leaf & Smoker) - lavender essential oil (1cc & 2cc & 3cc & 4cc) - laurel essential oil (1cc & 2cc & 3cc & 4cc) - control) were applied to the honeycombs with moths. In 2017, the B401 group had the highest wax moth damage area, and the group with the lowest wax moth damage area was determined as lavender 1cc; In 2018, the highest wax moth damage area was found in the walnut smoker group, while the lowest wax moth damage area was found in sulfur, walnut leaves, laurel 1cc - 2cc - 4cc, lavender 1cc - 2cc - 3cc - 4cc and control groups. In addition, sulfur residue amount (mean 128,18 mg/kg) in honeycomb was measured in the sulfur-treated group. Phase 1 of the project was completed, and the most important sub-groups among walnut (leaf) - lavender (1cc) and laurel (4cc) groups were identified. Accordingly, it is planned to carry out these treatments ((sulfur - B401 - walnut (leaf) - lavender (1cc) and laurel (4cc)) on honeycombs with do not contain moths, and later, it is planned to examine the effects of the treatment on the offspring area and honey yield by giving these honeycombs to the hives, in the 2nd stage of the project (2019-2020).

Keywords: honey bee, lavender essential oil, laurel essential oil, walnut, wax moth

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Authors: Sobhy Fathy A. Hashesh

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The study was carried out in the High School Classes of Andalus Private Schools, boys section, using control and experimental groups that were randomly assigned. The study investigated the effect of Al-Andalus Improvement Model (AIM) on the development of students’ skills acquiring. The society of the study composed of Al-Andalus Private Schools, high school students, boys Section (N=700), while the sample of the study composed of four randomly assigned groups two groups of teachers (N=16) and two groups of students (N=42) with one experimental group and one control group for teachers and their students respectively. The study followed the quantitative and qualitative approaches in collecting and analyzing data to investigate the study hypotheses. Results of the study revealed that there were significant statistical differences in teachers’ performances and students' skills acquiring for the favor of the experimental groups and there was a strong correlation between the teachers performances and the students skills acquiring. The study recommended the implementation of the AIM model for the sake of teachers performances and students’ learning outcomes.

Keywords: AIM, improvement model, Classera, Al-Andalus Improvement Model.

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Authors: Rahul Saraswat

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More recently, a focus has been given to replacing machined stainless steel metal flow fields with inexpensive wire mesh current collectors. The flow fields are based on simple woven wire mesh screens of various stainless steels, which are sandwiched between a thin metal plate of the same material to create a bipolar plate/flow field configuration for use in a stack. Major advantages of using stainless steel wire screens include the elimination of expensive raw materials as well as machining and/or other special fabrication costs. The objective of the project is to improve the performance of the passive direct methanol fuel cell without increasing the cost of the cell and to make it as compact and light as possible. From the literature survey, it was found that very little is done in this direction, and the following methodology was used. 1. The passive direct methanol fuel cell (DMFC) can be made more compact, lighter, and less costly by changing the material used in its construction. 2. Controlling the fuel diffusion rate through the cell improves the performance of the cell. A passive liquid feed direct methanol fuel cell (DMFC) was fabricated using a given MEA (Membrane Electrode Assembly) and tested for different current collector structures. Mesh current collectors of different mesh densities along with different support structures, were used, and the performance was found to be better. Methanol concentration was also varied. Optimisation of mesh size, support structure, and fuel concentration was achieved. Cost analysis was also performed hereby. From the performance analysis study of DMFC, we can conclude with the following points: Area specific resistance (ASR) of wire mesh current collectors is lower than the ASR of stainless steel current collectors. Also, the power produced by wire mesh current collectors is always more than that produced by stainless steel current collectors. 1. Low or moderate methanol concentrations should be used for better and stable DMFC performance. 2. Wiremesh is a good substitute for stainless steel for current collector plates of passive DMFC because of its lower cost (by about 27 %), flexibility, and light in weight characteristics of wire mesh.

Keywords: direct methanol fuel cell, membrane electrode assembly, mesh, mesh size, methanol concentration, support structure

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Authors: Adia Fatima, Naila Chand, Rifat Ullah Khan

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The goal of this study was to determine how fennel seed supplementation affected broiler growth, carcass quality, antioxidant status, and antibody titer in heat-stressed broilers. A total of 720 one-day-old broiler chickens were weighed and assigned to 28-floor pens (25 broiler chickens per pen). The broiler chickens were housed in a thermoneutral (TN) environment and were exposed to heat stress (HS). For 23 hours, the broiler chickens were kept under fluorescent lighting. For 35d, HS broiler chickens were fed a control diet and three levels of fennel seeds powder at rates of 15g/kg (Fen-15), 20 g/kg (Fen-20), and 25 g/kg (Fen-25). Overall feed intake, weight gain, and dressing % were considerably greater (P < 0.05) in Fen-25 and TN, but FCR was significantly reduced (P<0.01) in the same groups. When TN, Fen-20, and Fen-25 were compared to the control, malondialdehyde (MDA), paraoxonase (PON1), and antibody titer against New Castle disease (ND) were considerably (P < 0.05) greater. Further, the linear and quadratic response was for feed intake, weight gain, FCR, MDA, PON1, and ND titer. It was concluded that Fen-20 and Fen-25 increased broiler growth, carcass quality, antioxidant status, and immunological response under HS conditions.

Keywords: heat stress, growth, antioxidant, immunity

Procedia PDF Downloads 101

Authors: Ojo Oo, Akinde S. B., Kiilani A. O., Jayeola Jo, Jogbodo T. M., Ajani Ka, Olaniyan So, Adeagbo Oy, Bolarinwa Ra, Durosomo Ha, Sule W. F.

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Lockdown imposed to control SARS-CoV-2 transmission hampered malaria control services in Nigeria. Considering COVID-19 vaccination, we assessed Plasmodium falciparum (Pf) antigen and SARS-CoV-2 immunoglobulin-G (IgG) positivity among adults in Osogbo, Osun State, Nigeria. Consenting attendees of four Healthcare Centres were consecutively enrolled for blood sampling; relevant socio-demographic/behavioral/clinical/environmental data were collected with a questionnaire. Samples were tested, using commercial rapid test kits, for Pf antigen and SARS-CoV-2 IgG and results were analyzed using logistic regression. Participants' mean age was 40.99 years (n=200), and they were predominantly females (84.5%), traders/businessmen/women (86.0%), with self-reported receipt of COVID-19 vaccine from 123 (61.5%). Pf antigen positivity was 17.5% (95% CI: 12.23–22.77%) with age (p=0.004), marital status (p=0.004), report of stagnant water around the workplace (p=0.041) and bush around homes (p=0.008) being associated. SARS-CoV-2 IgG positivity was 56.5% (95% CI: 49.63–63.37%) with age (p=0.012) and receipt of COVID-19 vaccination (p=0.001) being associated. Although the vaccinated had a 22.8 times higher likelihood of IgG positivity, no factor was predictive of COVID-19 vaccine receipt. We report 17.5% Pf antigen positivity with four predictors, and 56.5% SARS-CoV-2 IgG positivity with two predictors.

Keywords: COVID-19, vaccine, IgG, Plasmodium falciparum, SARS-CoV-2

Procedia PDF Downloads 141

Authors: Stanislav Perepechko

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Industrial companies - one of the major sources of harmful substances to the atmosphere. The main cause of pollution on the concrete plants are cement dust emissions. All the cement silos, pneumatic transport, and ventilation systems equipped with filters, to avoid this. Today, many Russian companies have to decide on replacement morally and physically outdated filters and guided back to the electrostatic filters as usual equipment. The offered way of a cleaning of waste-free filtering of air differs in the fact that a filtering medium of the filter is used in concrete manufacture. Basalt is widespread and pollution-free material. In the course of cleaning, one part of basalt fiber and cement immediately goes to the mixer through flow-control units of initial basalt fiber and cement. Another part of basalt fiber goes to filters for purification of the air used in systems of an air lift, and ventilating emissions passes through them, and with trapped particles also goes to the mixer through flow-control units of the basalt fiber fulfilled in filters. At the same time, regulators are adjusted in such a way that total supply of basalt fiber and cement into the mixer remains invariable and corresponds to a given technological mode.

Keywords: waste-free air filtration, concrete, basalt fiber, building automation

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Authors: Darius Jakimavicius

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Artificial intelligence is the subject of intense debate in the international arena, identified both as a technological breakthrough and as a component of the strategic stability effect. Both the kinetic and non-kinetic development of AI and its application in the national strategies of the great powers may trigger a change in the security situation. Artificial intelligence is generally faster, more capable and more efficient than humans, and there is a temptation to transfer decision-making and control responsibilities to artificial intelligence. Artificial intelligence, which, once activated, can select and act on targets without further intervention by a human operator, blurs the boundary between human or robot (machine) warfare, or perhaps human and robot together. Artificial intelligence acts as a force multiplier that speeds up decision-making and reaction times on the battlefield. The role of humans is increasingly moving away from direct decision-making and away from command and control processes involving the use of force. It is worth noting that the autonomy and precision of AI systems make the process of strategic stability more complex. Deterrence theory is currently in a phase of development in which deterrence is undergoing further strain and crisis due to the complexity of the evolving models enabled by artificial intelligence. Based on the concept of strategic stability and deterrence theory, it is appropriate to develop further research on the development and impact of AI in order to assess AI from both a scientific and technical perspective: to capture a new niche in the scientific literature and academic terminology, to clarify the conditions for deterrence, and to identify the potential uses, impacts and possibly quantities of AI. The research problem is the impact of artificial intelligence developed by great powers on strategic stability. This thesis seeks to assess the impact of AI on strategic stability and deterrence principles, with human exclusion from the decision-making and control loop as a key axis. The interaction between AI and human actions and interests can determine fundamental changes in great powers' defense and deterrence, and the development and application of AI-based great powers strategies can lead to a change in strategic stability.

Keywords: artificial inteligence, strategic stability, deterrence theory, decision making loop

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Authors: Mohammad Hossein Mohammadi Sanjani, Ashknaz Oraee, Oriol Gomis Bellmunt, Vinicius Albernaz Lacerda Freitas

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The use of distributed and renewable sources in power systems has grown significantly, recently. One the most popular sources are wind farms which have grown massively. However, ¬wind farms are connected to the grid, this can cause problems such as reduced voltage stability, frequency fluctuations and reduced dynamic stability. Variable speed generators (asynchronous) are used due to the uncontrollability of wind speed specially Doubley Fed Induction Generators (DFIG). The most important disadvantage of DFIGs is its sensitivity to voltage drop. In the case of faults, a large volume of reactive power is induced therefore, use of FACTS devices such as SVC and STATCOM are suitable for improving system output performance. They increase the capacity of lines and also passes network fault conditions. In this paper, in addition to modeling the reactive power control system in a DFIG with converter, FACTS devices have been used in a DFIG wind turbine to improve the stability of the power system containing two synchronous sources. In the following paper, recent optimal control systems have been designed to minimize fluctuations caused by system disturbances, for FACTS devices employed. For this purpose, a suitable method for the selection of nine parameters for MPSH-phase-post-phase compensators of reactive power compensators is proposed. The design algorithm is formulated ¬¬as an optimization problem searching for optimal parameters in the controller. Simulation results show that the proposed controller Improves the stability of the network and the fluctuations are at desired speed.

Keywords: renewable energy sources, optimization wind power plant, stability, reactive power compensator, double-feed induction generator, optimal control, genetic algorithm

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Authors: Lusine S. Stepanyan, Elina V. Asriyan.

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It is known, that the efficiency of management depend on individual characteristics of manager. In case, was shown the role of personal position in the efficiency of management. Current research is aimed at reveal psychological and psychophysiological basis efficiency of management and finding ways of increasing the productivity of management that is most essential and topical problems of modern society. To understand the investigated phenomenon it was applied a complex approach. The Eysenk questionnaire was used for determining the level of aggression, frustration, anxiety and rigidity. The test of egocentric associations was used for determining the level of egocentrism. The test of COS (communicativeness and organizational skills) was used for diagnosing the level of communicativeness. The integral index of job satisfaction was used for diagnosis the efficiency of management activity. Then, the relationship between the above mentioned mental state, communicativeness, self-esteem, job satisfaction, locus of control, and egocentrism was investigated. The obtained results have shown the positive correlation between the egocentrism and frustration, anxiety and also the negative correlation with job satisfaction and communicativeness. Intergroup analyses has revealed the significant differences by communicativeness and the internality’ level. The revealed results can be used for diagnosis of efficiency of management.

Keywords: egocentrism, locus control, mental state, job satisfaction, professional activity

Procedia PDF Downloads 368

Authors: Zhichao Song, Swanand Vaidya

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Nowadays, most portable (e.g., smartphones) and wearable (e.g., smartwatches and earphones) consumer hardware are designed to be dustproof following IP5 or IP6 ratings to ensure the product is able to handle potentially dusty outdoor environments. On the other hand, the design guideline is relatively vague for indoor devices (e.g., smart displays and speakers). While it is generally believed that the indoor environment is much less dusty, in certain circumstances, dust ingression is still able to cause functional failures, such as microphone frequency response shift and camera black spot, or cosmetic dissatisfaction, mainly the dust build up in visible pockets and gaps which is hard to clean. In this paper, we developed a simulation methodology to analyze dust settlement and ingression into known ports of a device. A closed system is initialized with dust particles whose sizes follow Weibull distribution based on data collected in a user study, and dust particle movement was approximated as a settlement in stationary fluid, which is governed by Stokes’ law. Following this method, we simulated dust ingression into MEMS microphone through the acoustic port and protective mesh. Various design and environmental parameters are evaluated including mesh pore size, acoustic port depth-to-diameter ratio, mass density of dust material and inclined angle of microphone port. Although the dependencies of dust resistance on these parameters are all monotonic, smaller mesh pore size, larger acoustic depth-to-opening ratio and more inclined microphone placement (towards horizontal direction) are preferred for dust resistance; these preferences may represent certain trade-offs in audio performance and compromise in industrial design. The simulation results suggest the quantitative ranges of these parameters, with more pronounced effects in the improvement of dust resistance. Based on the simulation results, we proposed several design guidelines that intend to achieve an overall balanced design from audio performance, dust resistance, and flexibility in industrial design.

Keywords: dust settlement, numerical simulation, microphone design, Weibull distribution, Stoke's equation

Procedia PDF Downloads 107