Search results for: recruitment model

Authors: U. Ali Rahoma, Nabil Esawy, Fawzia Ibrahim Moursy, A. H. Hassan, Samy A. Khalil, Ashraf S. Khamees

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The design of any solar energy conversion system requires the knowledge of solar radiation data obtained over a long period. Satellite data has been widely used to estimate solar energy where no ground observation of solar radiation is available, yet there are limitations on the temporal coverage of satellite data. Reanalysis is a “retrospective analysis” of the atmosphere parameters generated by assimilating observation data from various sources, including ground observation, satellites, ships, and aircraft observation with the output of NWP (Numerical Weather Prediction) models, to develop an exhaustive record of weather and climate parameters. The evaluation of the performance of reanalysis datasets (ERA-5) for North Africa against high-quality surface measured data was performed using statistical analysis. The estimation of global solar radiation (GSR) distribution over six different selected locations in North Africa during ten years from the period time 2011 to 2020. The root means square error (RMSE), mean bias error (MBE) and mean absolute error (MAE) of reanalysis data of solar radiation range from 0.079 to 0.222, 0.0145 to 0.198, and 0.055 to 0.178, respectively. The seasonal statistical analysis was performed to study seasonal variation of performance of datasets, which reveals the significant variation of errors in different seasons—the performance of the dataset changes by changing the temporal resolution of the data used for comparison. The monthly mean values of data show better performance, but the accuracy of data is compromised. The solar radiation data of ERA-5 is used for preliminary solar resource assessment and power estimation. The correlation coefficient (R2) varies from 0.93 to 99% for the different selected sites in North Africa in the present research. The goal of this research is to give a good representation for global solar radiation to help in solar energy application in all fields, and this can be done by using gridded data from European Centre for Medium-Range Weather Forecasts ECMWF and producing a new model to give a good result.

Keywords: solar energy, solar radiation, ERA-5, potential energy

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Authors: Yasemin Akar, Jan G. Wissink, Herlina Herlina

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The effect of various levels of contamination on the interfacial air–water gas transfer velocity is studied by Direct Numerical Simulation (DNS). The interfacial gas transfer is driven by isotropic turbulence, introduced at the bottom of the computational domain, diffusing upwards. The isotropic turbulence is generated in a separate, concurrently running the large-eddy simulation (LES). The flow fields in the main DNS and the LES are solved using fourth-order discretisations of convection and diffusion. To solve the transport of dissolved gases in water, a fifth-order-accurate WENO scheme is used for scalar convection combined with a fourth-order central discretisation for scalar diffusion. The damping effect of the surfactant contamination on the near surface (horizontal) velocities in the DNS is modelled using horizontal gradients of the surfactant concentration. An important parameter in this model, which corresponds to the level of contamination, is ReMa⁄We, where Re is the Reynolds number, Ma is the Marangoni number, and We is the Weber number. It was previously found that even small levels of contamination (ReMa⁄We small) lead to a significant drop in the interfacial gas transfer velocity KL. It is known that KL depends on both the Schmidt number Sc (ratio of the kinematic viscosity and the gas diffusivity in water) and the surface divergence β, i.e. K_L∝√(β⁄Sc). Previously it has been shown that this relation works well for surfaces with low to moderate contamination. However, it will break down for β close to zero. To study the validity of this dependence in the presence of surface contamination, simulations were carried out for ReMa⁄We=0,0.12,0.6,1.2,6,30 and Sc = 2, 4, 8, 16, 32. First, it will be shown that the scaling of KL with Sc remains valid also for larger ReMa⁄We. This is an important result that indicates that - for various levels of contamination - the numerical results obtained at low Schmidt numbers are also valid for significantly higher and more realistic Sc. Subsequently, it will be shown that - with increasing levels of ReMa⁄We - the dependency of KL on β begins to break down as the increased damping of near surface fluctuations results in an increased damping of β. Especially for large levels of contamination, this damping is so severe that KL is found to be underestimated significantly.

Keywords: contamination, gas transfer, surfactants, turbulence

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Authors: Stephen Wagman

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This paper identifies three common structures in English sentences that are important for understanding academic texts, regardless of the characteristics or background of the readers or whether they are reading English as a second or a foreign language. Adapting a model from the Humanities, the explication of texts used in literary studies, the paper analyses sample sentences to reveal structures that enable the reader not only to decide which words are necessary for understanding the main ideas but to make the decision without knowing the meaning of the words. By their very syntax noun structures point to the key word for understanding them. As a rule, the key noun is followed by easily identifiable prepositions, relative pronouns, or verbs and preceded by single adjectives. With few exceptions, the modifiers are unnecessary for understanding the idea of the sentence. In addition, sentences are often structured by lists in which the items frequently consist of parallel groups of words. The principle of a list is that all the items are similar in meaning and it is not necessary to understand all of the items to understand the point of the list. This principle is especially important when the items are long or there is more than one list in the same sentence. The similarity in meaning of these items enables readers to reduce sentences that are hard to grasp to an understandable core without excessive use of a dictionary. Finally, the idea of subordination and the identification of the subordinate parts of sentences through connecting words makes it possible for readers to focus on main ideas without having to sift through the less important and more numerous secondary structures. Sometimes a main idea requires a subordinate one to complete its meaning, but usually, subordinate ideas are unnecessary for understanding the main point of the sentence and its part in the development of the argument from sentence to sentence. Moreover, the connecting words themselves indicate the functions of the subordinate structures. These most frequently show similarity and difference or reasons and results. Recognition of all of these structures can not only enable students to read more efficiently but to focus their attention on the development of the argument and this rather than a multitude of unknown vocabulary items, the repetition in lists, or the subordination in sentences are the one necessary element for comprehension of academic articles.

Keywords: development of the argument, lists, noun structures, subordination

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Authors: C. O. Igberi, M. U. Amadi

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This research paper on the impact of import restriction on rice production in Nigeria is aimed at finding/proffering valid solutions to the age long problem of rice self-sufficiency, through a better understanding of policy measures used in the past, in this case, the effectiveness of rice import restriction of the early 90’s. It tries to answer the questions of; import restriction boosting domestic rice production and the macroeconomic determining factors of Gross Domestic Rice Product (GDRP). The research probe is investigated through literature and analytical frameworks, such that time series data on the GDRP, Gross Fixed Capital Formation (GFCF), average foreign rice producers’ prices(PPF), domestic producers’ prices (PPN) and the labour force (LABF) are collated for analysis (with an import restriction dummy variable, POL1). The research objectives/hypothesis are analysed using; Cointegration, Vector Error Correction Model (VECM), Impulse Response Function (IRF) and Granger Causality Test(GCT) methodologies. Results show that in the short-run error correction specification for GDRP, a percentage (1%) deviation away from the long-run equilibrium in a current quarter is only corrected by 0.14% in the subsequent quarter. Also, the rice import restriction policy had no significant effect on the GDRP at this time. Other findings show that the policy period has, in fact, had effects on the PPN and LABF. The choice variables used are valid macroeconomic factors that explain the GDRP of Nigeria, as adduced from the IRF and GCT, and in the long-run. Policy recommendations suggest that the import restriction is not disqualified as a veritable tool for improving domestic rice production, rather better enforcement procedures and strict adherence to the policy dictates is needed. Furthermore, accompanying policies which drive public and private capital investment and accumulation must be introduced. Also, employment rate and labour substitution in the agricultural sector should not be drastically changed, rather its welfare and efficiency be improved.

Keywords: import restriction, gross domestic rice production, cointegration, VECM, Granger causality, impulse response function

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Authors: Pauliasi Tony Fakahau

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This paper provides an overview of the impact of the revenue reform programme on vulnerable communities in the Kingdom of Tonga. Economic turmoil and mismanagement during the late 1990s forced the government to seek technical and financial assistance from the Asian Development Bank to undertake a comprehensive Economic and Public Sector Reform (EPSR) programme. The EPSR is a Western model recommended by donor agencies as the solution to Tonga’s economic challenges. The EPSR programme included public sector reform, private sector growth, and revenue generation. Tax reform was the main tool for revenue generation, which set out to strengthen tax compliance and administration as well as implement a value-added consumption tax. The EPSR is based on Western values and ideology but failed to recognise that Tongan cultural values are important to the local community. Two participant groups were interviewed. Participant group one consisted of 51 people representing vulnerable communities. Participant group two consisted of six people from the government and business sector who were from the elite of Tongan society. The Kakala Research Methodology provided the framework for the research, and the Talanoa Research Method was used to conduct semi-structured interviews in the homes of the first group and in the workplaces of the second group. The research found a heavy burden of the consumption tax on the purchasing power of participant group one (vulnerable participants), having an impact on nearly every financial transaction they made. Participant group ones’ main financial priorities were kavenga fakalotu (obligations to the church), kavenga fakafāmili (obligations to the family) and kavenga fakafonua (obligations to cultural events for the village, nobility, and royalty). The findings identified inequalities of the revenue reform, especially from consumption tax, for vulnerable people and communities compared to the elite of society. The research concluded that government and donor agencies need ameliorating policies to reduce the burden of tax on vulnerable groups more susceptible to the impact of revenue reform.

Keywords: tax reform, tonga vulnerable community revenue, revenue reform, public sector reform

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Authors: Roshanim Koris, Norashidah Mohamed Nor, Sharifah Azizah Haron, Normaz Wana Ismail, Syed Mohamed Aljunid Syed Junid, Amrizal Muhammad Nur, Asrul Akmal Shafie, Suraya Yusuff, Namaitijiang Maimaiti

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An ageing population has huge implications for virtually every aspect of Malaysian societies. The elderly consume a greater volume of healthcare facilities not because they are older, but because of they are sick. The chronic comorbidities and deterioration of cognitive ability would lead the elderly’s health to become worst. This study aims to provide a comprehensive estimate of the direct and indirect costs of health care used in a nationally representative sample of community-dwelling elderly with dementia and as well as the determinants of healthcare cost. A survey using multi-stage random sampling techniques recruited a final sample of 2274 elderly people (60 years and above) in the state of Johor, Perak, Selangor and Kelantan. Mini Mental State Examination (MMSE) score was used to measure the cognitive capability among the elderly. Only the elderly with a score less than 19 marks were selected for further analysis and were classified as dementia. By using a two-part model findings also indicate household income and education level are variables that strongly significantly influence the healthcare cost among elderly with dementia. A number of visits and admission are also significantly affect healthcare expenditure. The comorbidity that highly influences healthcare cost is cancer and seeking the treatment in private facilities is also significantly affected the healthcare cost among the demented elderly. The level of dementia severity is not significant in determining the cost. This study is expected to attract the government's attention and act as a wake-up call for them to be more concerned about the elderly who are at high risk of having chronic comorbidities and cognitive problems by providing more appropriate health and social care facilities. The comorbidities are one of the factor that could cause dementia among elderly. It is hoped that this study will promote the issues of dementia as a priority in public health and social care in Malaysia.

Keywords: ageing population, dementia, elderly, healthcare cost, healthcare utiliztion

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Authors: Abdul Mutalib Md Jani, Abdul Hadi Mahmud, Mohd Tajuddin Mohd Ali

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The rapid growth of interest in surface modification of nanostructures materials that exhibit improved structural and functional properties is attracting more researchers. The unique properties of highly ordered nanoporous anodic aluminium oxide (NAAO) membrane have been proposed as a platform for biosensing applications. They exhibit excellent physical and chemical properties with high porosity, high surface area, tunable pore sizes and excellent chemical resistance. In this study, NAAO was functionalized with 3-aminopropyltriethoxysilane (APTES) to prepared silane-modified NAAO. Amine functional groups are formed on the surface of NAAO during silanization and were characterized using Fourier Transform Infrared spectroscopy (FTIR). The synthesis of multi segment of peptide on NAAO surfaces can be realized by changing the surface chemistry of the NAAO membrane via click chemistry. By click reactions, utilizing alkyne terminated with amino group, various peptides tagged on NAAO can be envisioned from chiral natural or unnatural amino acids using standard coupling methods (HOBt, EDCI and HBTU). This strategy seemly versatile since coupling strategy of dipeptide with another amino acids, leading to tripeptide, tetrapeptide or pentapeptide, can be synthesized without purification. When an appropriate terminus is selected, multiple segments of amino acids can be successfully synthesized on the surfaces. The immobilized NAAO should be easily separated from the reaction medium by conventional filtration, thus avoiding complicated purification methods. Herein, we proposed to synthesize multi fragment peptide as a model for capturing and attaching various small biomolecules on NAAO surfaces and can be also applied as biosensing device, drug delivery systems and biocatalyst.

Keywords: nanoporous anodic aluminium oxide, silanization, peptide synthesise, click chemistry

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Authors: Prajna Paramita Mohapatra, Pamu Dobbidi

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Lithium ferrite (LiFe5O8) has potential applications as a component of microwave magnetic devices such as circulators and monolithic integrated circuits. For efficient device applications, spinel ferrites in the form of thin films are highly required. It is necessary to improve their magnetic and dielectric behavior by optimizing the processing parameters during deposition. The lithium ferrite thin films are deposited on Pt/Si substrate using the pulsed laser deposition technique (PLD). As controlling the film thickness is the easiest parameter to tailor the strain, we deposited the thin films having different film thicknesses (160 nm, 200 nm, 240 nm) at oxygen partial pressure of 0.001 mbar. The formation of single phase with spinel structure (space group - P4132) is confirmed by the XRD pattern and the Rietveld analysis. The optical bandgap is decreased with the increase in thickness. FESEM confirmed the formation of uniform grains having well separated grain boundaries. Further, the film growth and the roughness are analyzed by AFM. The root-mean-square (RMS) surface roughness is decreased from 13.52 nm (160 nm) to 9.34 nm (240 nm). The room temperature magnetization is measured with a maximum field of 10 kOe. The saturation magnetization is enhanced monotonically with an increase in thickness. The magnetic resonance linewidth is obtained in the range of 450 – 780 Oe. The dielectric response is measured in the frequency range of 104 – 106 Hz and in the temperature range of 303 – 473 K. With an increase in frequency, the dielectric constant and the loss tangent of all the samples decreased continuously, which is a typical behavior of conventional dielectric material. The real part of the dielectric constant and the dielectric loss is increased with an increase in thickness. The contribution of grain and grain boundaries is also analyzed by employing the equivalent circuit model. The highest dielectric constant is obtained for the film having a thickness of 240 nm at 104 Hz. The obtained results demonstrate that desired response can be obtained by tailoring the film thickness for the microwave magnetic devices.

Keywords: PLD, optical response, thin films, magnetic response, dielectric response

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Authors: N. W. I. A. Jayawardana, W. A. T. A. Jayalath, W. M. T. Madhujith, U. Ralapanawa, R. S. Jayasekera, S. A. S. B. Alagiyawanna, A. M. K. R. Bandara, N. S. Kalupahana

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There is mounting evidence to the effect that dietary and lifestyle changes affect the incidence of non-communicable diseases (NCDs). This study was conducted to investigate the association of diet, physical activity, smoking, alcohol consumption and duration of sleep with overweight, obesity, hypertension and diabetes in a cohort of males from the Central Province of Sri Lanka. A total of 2694 individuals aged between 17 – 68 years (Mean = 31) were included in the study. Body Mass Index cutoff values for Asians were used to categorize the participants as normal, overweight and obese. The dietary data were collected using a food frequency questionnaire [FFQ] and data on the level of physical activity, smoking, alcohol consumption and sleeping hours were obtained using a self-administered validated questionnaire. Systolic and diastolic blood pressure, random blood glucose levels were measured to determine the incidence of hypertension and diabetes. Among the individuals, the prevalence of overweight and obesity were 34% and 16.4% respectively. Approximately 37% of the participants suffered from hypertension. Overweight and obesity were associated with older age men (P<0.0001), frequency of smoking (P=0.0434), alcohol consumption level (P=0.0287) and the quantity of lipid intake (P=0.0081). Consumption of fish (P=0.6983) and salty snacks (P=0.8327), sleeping hours (P=0.6847) and the level of physical activity were not significantly (P=0.3301) associated with the incidence of overweight and obesity. Based on the fitted model, only age was significantly associated with hypertension (P < 0.001). Further, age (P < 0.0001), sleeping hours (P=0.0953) and consumption of fatty foods (P=0.0930) were significantly associated with diabetes. Age was associated with higher odds of pre diabetes (OR:1.089;95% CI:1.053,1.127) and diabetes (OR:1.077;95% CI:1.055,1.1) whereas 7-8 hrs. of sleep per day was associated with lesser odds of diabetes (OR:0.403;95% CI:0.184,0.884). High prevalence of overweight, obesity and hypertension in working-age males is a threatening sign for this area. As this population ages in the future and urbanization continues, the prevalence of above risk factors will likely to escalate.

Keywords: age, males, non-communicable diseases, obesity

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Authors: Xianglu Tang, Zhenxue Jiang, Zhuo Li

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Characterization of shale multi scale heterogeneity is an important part to evaluate size and space distribution of shale gas reservoirs in sedimentary basins. The origin of shale heterogeneity has always been a hot research topic for it determines shale micro characteristics description and macro quality reservoir prediction. Shale multi scale heterogeneity was discussed based on thin section observation, FIB-SEM, QEMSCAN, TOC, XRD, mercury intrusion porosimetry (MIP), and nitrogen adsorption analysis from 30 core samples in Silurian Longmaxi formation. Results show that shale heterogeneity can be characterized by pore structure and mineral composition. The heterogeneity of shale pore is showed by different size pores at nm-μm scale. Macropores (pore diameter > 50 nm) have a large percentage of pore volume than mesopores (pore diameter between 2~ 50 nm) and micropores (pore diameter < 2nm). However, they have a low specific surface area than mesopores and micropores. Fractal dimensions of the pores from nitrogen adsorption data are higher than 2.7, what are higher than 2.8 from MIP data, showing extremely complex pore structure. This complexity in pore structure is mainly due to the organic matter and clay minerals with complex pore network structures, and diagenesis makes it more complicated. The heterogeneity of shale minerals is showed by mineral grains, lamina, and different lithology at nm-km scale under the continuous changing horizon. Through analyzing the change of mineral composition at each scale, random arrangement of mineral equal proportion, seasonal climate changes, large changes of sedimentary environment, and provenance supply are considered to be the main reasons that cause shale minerals heterogeneity from microcosmic to macroscopic. Due to scale effect, the change of shale multi scale heterogeneity is a discontinuous process, and there is a transformation boundary between homogeneous and in homogeneous. Therefore, a shale multi scale heterogeneity changing model is established by defining four types of homogeneous unit at different scales, which can be used to guide the prediction of shale gas distribution from micro scale to macro scale.

Keywords: heterogeneity, homogeneous unit, multiscale, shale

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Authors: Javier Muro, Anja Linstadter, Florian Manner, Lisa Schwarz, Stephan Wollauer, Paul Magdon, Gohar Ghazaryan, Olena Dubovyk

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Monitoring the trade-off between biomass production and biodiversity in grasslands is critical to evaluate the effects of management practices across environmental gradients. New generations of remote sensing sensors and machine learning approaches can model grasslands’ characteristics with varying accuracies. However, studies often fail to cover a sufficiently broad range of environmental conditions, and evidence suggests that prediction models might be case specific. In this study, biomass production and biodiversity indices (species richness and Fishers’ α) are modeled in 150 grassland plots for three sites across Germany. These sites represent a North-South gradient and are characterized by distinct soil types, topographic properties, climatic conditions, and management intensities. Predictors used are derived from Sentinel-1 & 2 and a set of topoedaphic variables. The transferability of the models is tested by training and validating at different sites. The performance of feed-forward deep neural networks (DNN) is compared to a random forest algorithm. While biomass predictions across gradients and sites were acceptable (r2 0.5), predictions of biodiversity indices were poor (r2 0.14). DNN showed higher generalization capacity than random forest when predicting biomass across gradients and sites (relative root mean squared error of 0.5 for DNN vs. 0.85 for random forest). DNN also achieved high performance when using the Sentinel-2 surface reflectance data rather than different combinations of spectral indices, Sentinel-1 data, or topoedaphic variables, simplifying dimensionality. This study demonstrates the necessity of training biomass and biodiversity models using a broad range of environmental conditions and ensuring spatial independence to have realistic and transferable models where plot level information can be upscaled to landscape scale.

Keywords: ecosystem services, grassland management, machine learning, remote sensing

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Authors: Jinhoa Lee

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The relationships between environmental quality, energy use and economic output have created growing attention over the past decades among researchers and policy makers. Focusing on the empirical aspects of the role of CO2 emissions and energy use in affecting the economic output, this paper is an effort to fulfill the gap in a comprehensive case study at a country level using modern econometric techniques. To achieve the goal, this country-specific study examines the short-run and long-run relationships among energy consumption (using disaggregated energy sources: crude oil, coal, natural gas, electricity), carbon dioxide (CO2) emissions and gross domestic product (GDP) for Turkey using time series analysis from the year 1980-2010. To investigate the relationships between the variables, this paper employs the Phillips–Perron (PP) test for stationarity, Johansen maximum likelihood method for cointegration and a Vector Error Correction Model (VECM) for both short- and long-run causality among the research variables for the sample. All the variables in this study show very strong significant effects on GDP in the country for the long term. The long-run equilibrium in the VECM suggests negative long-run causalities from consumption of petroleum products and the direct combustion of crude oil, coal and natural gas to GDP. Conversely, positive impacts of CO2 emissions and electricity consumption on GDP are found to be significant in Turkey during the period. There exists a short-run bidirectional relationship between electricity consumption and natural gas consumption. There exists a positive unidirectional causality running from electricity consumption to natural gas consumption, while there exists a negative unidirectional causality running from natural gas consumption to electricity consumption. Moreover, GDP has a negative effect on electricity consumption in Turkey in the short run. Overall, the results support arguments that there are relationships among environmental quality, energy use and economic output but the associations can to be differed by the sources of energy in the case of Turkey over of period 1980-2010.

Keywords: CO2 emissions, energy consumption, GDP, Turkey, time series analysis

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Authors: Aidan Battison, Neliswa Mama

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Environmental pollution by ionic species has been identified as one of the biggest challenges to the sustainable development of communities. The widespread use of organic and inorganic chemical products and the release of toxic chemical species from industrial waste have resulted in a need for advanced monitoring technologies for environment protection, remediation and restoration. Some of the disadvantages of conventional sensing methods include expensive instrumentation, well-controlled experimental conditions, time-consuming procedures and sometimes complicated sample preparation. On the contrary, the development of fluorescent chemosensors for biological and environmental detection of metal ions has attracted a great deal of attention due to their simplicity, high selectivity, eidetic recognition, rapid response and real-life monitoring. Coumarin derivatives S1 and S2 (Scheme 1) containing 1,2,3-triazole moieties at position -3- have been designed and synthesized from azide and alkyne derivatives by CuAAC “click” reactions for the detection of metal ions. These compounds displayed a strong preference for Fe3+ ions with complexation resulting in fluorescent quenching through photo-induced electron transfer (PET) by the “sphere of action” static quenching model. The tested metal ions included Cd2+, Pb2+, Ag+, Na+, Ca2+, Cr3+, Fe3+, Al3+, Cd2+, Ba2+, Cu2+, Co2+, Hg2+, Zn2+ and Ni2+. The detection limits of S1 and S2 were determined to be 4.1 and 5.1 uM, respectively. Compound S1 displayed the greatest selectivity towards Fe3+ in the presence of competing for metal cations. S1 could also be used for the detection of Fe3+ in a mixture of CH3CN/H¬2¬O. Binding stoichiometry between S1 and Fe3+ was determined by using both Jobs-plot and Benesi-Hildebrand analysis. The binding was shown to occur in a 1:1 ratio between the sensor and a metal cation. Reversibility studies between S1 and Fe3+ were conducted by using EDTA. The binding site of Fe3+ to S1 was determined by using 13 C NMR and Molecular Modelling studies. Complexation was suggested to occur between the lone-pair of electrons from the coumarin-carbonyl and the triazole-carbon double bond.

Keywords: chemosensor, "click" chemistry, coumarin, fluorescence, static quenching, triazole

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Authors: Slamet Setioboro, Rahutami Kusumaningsih, Prabowo Setiyawan, Danna Darmayadi

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Designing of cold-formed steel capacity connections often based on the formula used for hot rolled steel. It makes the result of the actual capacity connection doesn’t accurate anymore. When the hot rolled steel receives the axial load pull, it will have different characteristics. As the result, there will be failure result when designing Truss structure made of hot rolled steel. This research aims to determine the capacity of actual cold-formed steel connections section which is loaded by the axial tensile force. It will test the appeal of the connection using bolt grafting tool and screw grafting tool. The variations of the test will be on the type of connection (single and double slap), the number of the connection tools and connection configuration. Bold and screw connections failure mode observed in this research are different each other. Failure mode of bolted connections includes sliding pivot plate, tearing at the plate and cutting of the bolt head. While the failure mode of screw connections includes tilting, hole-bearing, pull over and cutting the screw body out. This research was conducted using a laboratory test of HW2-600S Universal Testing Machine model with ASTM E8. It has done in the materials testing laboratory of Mechanical Engineering Department, Faculty of Engineering UNNES. The results obtained through the laboratory diversification towards theoretical calculations using the standards specified in ISO 7971-2013 Cold-Rolled Steel Structures. Based on the research, it can be concluded that the effective connection in receiving force strength is bolted connections neither single nor double plate. The method used is by applying 4 bolts through 2 parallel lines configuration. Furthermore, this connection deals with the consequences of holding the highest Pmaks, lowest failure risk and getting a little kind of mode of failure.

Keywords: axial load, cold-formed steel, capacity connections, bolted connections, screw connections

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Authors: M. S. Nikitenko, S. A. Kizilov, D. Y. Khudonogov

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The paper considers an approach to a machine vision operating system combined with using a grid of light markers. This approach is used to solve several scientific and technical problems, such as measuring the capability of an apron feeder delivering coal from a lining return port to a conveyor in the technology of mining high coal releasing to a conveyor and prototyping an autonomous vehicle obstacle detection system. Primary verification of a method of calculating bulk material volume using three-dimensional modeling and validation in laboratory conditions with relative errors calculation were carried out. A method of calculating the capability of an apron feeder based on a machine vision system and a simplifying technology of a three-dimensional modelled examined measuring area with machine vision was offered. The proposed method allows measuring the volume of rock mass moved by an apron feeder using machine vision. This approach solves the volume control issue of coal produced by a feeder while working off high coal by lava complexes with release to a conveyor with accuracy applied for practical application. The developed mathematical apparatus for measuring feeder productivity in kg/s uses only basic mathematical functions such as addition, subtraction, multiplication, and division. Thus, this fact simplifies software development, and this fact expands the variety of microcontrollers and microcomputers suitable for performing tasks of calculating feeder capability. A feature of an obstacle detection issue is to correct distortions of the laser grid, which simplifies their detection. The paper presents algorithms for video camera image processing and autonomous vehicle model control based on obstacle detection machine vision systems. A sample fragment of obstacle detection at the moment of distortion with the laser grid is demonstrated.

Keywords: machine vision, machine vision operating system, light markers, measuring capability, obstacle detection system, autonomous transport

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Authors: Balasooriya B. M. C. M., Sujeeva N., Thowfeek Z., Siddiqa Omo, Liyanagunawardana J. E., Jayawardana Saiu, Manathunga S. S., Katulanda G. W.

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Introduction and objectives: Adrenal venous sampling (AVS) is the gold standard to discriminate unilateral primary aldosteronism (UPA) from bilateral disease (BPA). AVS is technically demanding and only performed in a limited number of centers worldwide. To the best of our knowledge, Except for one study conducted in India, no other research studies on this area have been conducted in South Asia. This study aimed to evaluate the effectiveness of AVS in the management of primary aldosteronism. Methods: A total of 32 patients who underwent AVS at the National Hospital of Sri Lanka from April 2021 to April 2023 were enrolled. Demographic, clinical and laboratory data were obtained retrospectively. A procedure was considered successful when adequate cannulation of both adrenal veins was demonstrated. Cortisol gradient across the adrenal vein (AV) and the peripheral vein was used to establish the success of venous cannulation. Lateralization was determined by the aldosterone gradient between the two sides. Continuous and categorical variables were summarized with mean, SD, and proportions, respectively. The mean and standard deviation of the contralateral suppression index (CSI) were estimated with an intercept-only Bayesian inference model. Results: Of the 32 patients, the average age was 52.47 +26.14 and 19 (59.4%) were males. Both AVs were successfully cannulated in 12 (37.5%). Among them, lateralization was demonstrated in 11(91.7%), and one was diagnosed as a bilateral disease. There were no total failures. Right AV cannulation was unsuccessful in 18 (56.25%), of which lateralization was demonstrated in 9 (50%), and others were inconclusive. Left AV cannulation was unsuccessful only in 2 (6.25%); one was lateralized, and the other remained inconclusive. The estimated mean of the CSI was 0.33 (89% credible interval 0.11-0.86). Seven patients underwent unilateral adrenalectomy and demonstrated significant improvement in blood pressure during follow-up. Two patients await surgery. Others were treated medically. Conclusions: Despite failure due to procedural difficulties, AVS remained useful in the management of patients with PA. Moreover, the success of the procedure needs experienced hands and advanced equipment to achieve optimal outcomes in PA.

Keywords: adrenal venous sampling, lateralization, contralateral suppression index, primary aldosteronism

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Authors: Betül sönmez, Fatma Azizoğlu, S. Bilge Hapçıoğlu, Aytolan Yıldırım

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Background: Social innovativeness contains the procurement of a sustainable benefit for a number of problems from working conditions to education, social development, health, and from environmental control to climate change, as well as the development of new social productions and services. Objectives: This study was conducted to determine the correlation between the social innovation tendency of nursing and medical faculty students and value types. Methods and participants: The population of this correlational study consisted of third-year students studying at a medical faculty and a nursing faculty in a public university in Istanbul. Ethics committee approval and permission from the school administrations were obtained in order to conduct the study and voluntary participation of the students in the study was ensured. 524 questionnaires were obtained with a total return rate of 57.1% (65.0% in nurse student and 52.1% in physic students). The data of the study were collected by using the Portrait Values Questionnaire and a questionnaire containing the Social Innovativeness Scale. Results: The effect of the subscale scores of Portrait Values Questionnaire on the total score of Social Innovativeness Scale was 26.6%. In the model where a significance was determined (F=37.566; p<0.01), the highest effect was observed in the subscale of universalism. The effect of subscale scores obtained from the Portrait Values Questionnaire, as well as age, gender and number of siblings was 25% on the Social Innovativeness in nursing students and 30.8% in medical faculty students. In both models where a significance was determined (p<0.01), the nursing students had the values of power, universalism and kindness, whereas the medical faculty students had the values of self-direction, stimulation, hedonism and universalism showed the highest effect in both models. Conclusions: Universalism is the value with the highest effect upon the social innovativeness in both groups, which is an expected result by the nature of professions. The effect of the values of independent thinking and self-direction, as well as openness to change involving quest for innovation (stimulation), which are observed in medical faculty students, also supports the literature of innovative behavior. These results are thought to guide educators and administrators in terms of developing socially innovative behaviors.

Keywords: social innovativeness, portrait values questionnaire, nursing students, medical faculty students

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Authors: Heeba A. Gurku

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Introduction: Cone Beam CT(CBCT) images play an integral part in proper patient positioning in cancer patients undergoing radiation therapy treatment. But these images are low in quality. The purpose of this study is to generate high-quality synthetic CT images from CBCT using generative models. Material and Methods: This study utilized two datasets from The Cancer Imaging Archive (TCIA) 1) Lung cancer dataset of 20 patients (with full view CBCT images) and 2) Pancreatic cancer dataset of 40 patients (only 27 patients having limited view images were included in the study). Cycle Generative Adversarial Networks (GAN) and its variant Attention Guided Generative Adversarial Networks (AGGAN) models were used to generate the synthetic CTs. Models were evaluated by visual evaluation and on four metrics, Structural Similarity Index Measure (SSIM), Peak Signal Noise Ratio (PSNR) Mean Absolute Error (MAE) and Root Mean Square Error (RMSE), to compare the synthetic CT and original CT images. Results: For pancreatic dataset with limited view CBCT images, our study showed that in Cycle GAN model, MAE, RMSE, PSNR improved from 12.57to 8.49, 20.94 to 15.29 and 21.85 to 24.63, respectively but structural similarity only marginally increased from 0.78 to 0.79. Similar, results were achieved with AGGAN with no improvement over Cycle GAN. However, for lung dataset with full view CBCT images Cycle GAN was able to reduce MAE significantly from 89.44 to 15.11 and AGGAN was able to reduce it to 19.77. Similarly, RMSE was also decreased from 92.68 to 23.50 in Cycle GAN and to 29.02 in AGGAN. SSIM and PSNR also improved significantly from 0.17 to 0.59 and from 8.81 to 21.06 in Cycle GAN respectively while in AGGAN SSIM increased to 0.52 and PSNR increased to 19.31. In both datasets, GAN models were able to reduce artifacts, reduce noise, have better resolution, and better contrast enhancement. Conclusion and Recommendation: Both Cycle GAN and AGGAN were significantly able to reduce MAE, RMSE and PSNR in both datasets. However, full view lung dataset showed more improvement in SSIM and image quality than limited view pancreatic dataset.

Keywords: CT images, CBCT images, cycle GAN, AGGAN

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Authors: Chiling Chen, Chiaoying Chou, Siyang Wu

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Taiwan locates at the west of Pacific Ocean and intersects between continental and marine climate. Typhoons frequently strike Taiwan and come with meteorological disasters, i.e., heavy flooding, landslides, loss of life and properties, etc. Global climate change brings more extremely meteorological disasters. So, develop techniques to improve disaster prevention and mitigation is needed, to improve rescue processes and rehabilitations is important as well. In this study, UAVs (Unmanned Aerial Vehicles) are applied to take instant images for improving the disaster investigation and rescue processes. Paddy rice fields in the central Taiwan are the study area. There have been attacked by heavy rain during the monsoon season in June 2016. UAV images provide the high ground resolution (3.5cm) with 3D Point Clouds to develop image discrimination techniques and digital surface model (DSM) on rice lodging. Firstly, image supervised classification with Maximum Likelihood Method (MLD) is used to delineate the area of rice lodging. Secondly, 3D point clouds generated by Pix4D Mapper are used to develop DSM for classifying the lodging levels of paddy rice. As results, discriminate accuracy of rice lodging is 85% by image supervised classification, and the classification accuracy of lodging level is 87% by DSM. Therefore, UAVs not only provide instant images of agricultural damage after the meteorological disaster, but the image discriminations on rice lodging also reach acceptable accuracy (>85%). In the future, technologies of UAVs and image discrimination will be applied to different crop fields. The results of image discrimination will be overlapped with administrative boundaries of paddy rice, to establish GIS-based assist system on agricultural damage discrimination. Therefore, the time and labor would be greatly reduced on damage detection and monitoring.

Keywords: Monsoon, supervised classification, Pix4D, 3D point clouds, discriminate accuracy

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Authors: Y. D. Lim, K. S. Yap, K. T. Ooi

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In recent years, environmental issue has been a hot topic in the world, especially the global warming effect caused by conventional non-environmentally friendly refrigerants has increased. Several studies of a more energy-efficient and environmentally friendly refrigeration system have been conducted in order to tackle the issue. In search of a better refrigeration system, CO2 refrigeration system has been proposed as a better option. However, the high throttling loss involved during the expansion process of the refrigeration cycle leads to a relatively low efficiency and thus the system is impractical. In order to improve the efficiency of the refrigeration system, it is suggested by replacing the conventional expansion valve in the refrigeration system with an expander. Based on this issue, a new type of expander-compressor combined unit, named Cross Vane Expander-Compressor (CVEC) was introduced to replace the compressor and the expansion valve of a conventional refrigeration system. A mathematical model was developed to calculate the performance of CVEC, and it was found that the machine is capable of saving the energy consumption of a refrigeration system by as much as 18%. Apart from energy saving, CVEC is also geometrically simpler and more compact. To further improve its efficiency, optimization study of the device is carried out. In this report, several design parameters of CVEC were chosen to be the variables of optimization study. This optimization study was done in a simulation program by using complex optimization method, which is a direct search, multi-variables and constrained optimization method. It was found that the main design parameters, which was shaft radius was reduced around 8% while the inner cylinder radius was remained unchanged at its lower limit after optimization. Furthermore, the port sizes were increased to their upper limit after optimization. The changes of these design parameters have resulted in reduction of around 12% in the total frictional loss and reduction of 4% in power consumption. Eventually, the optimization study has resulted in an improvement in the mechanical efficiency CVEC by 4% and improvement in COP by 6%.

Keywords: complex optimization method, COP, cross vane expander-compressor, CVEC, design optimization, direct search, energy saving, improvement, mechanical efficiency, multi variables

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Authors: Bassma A. Abdel Haleem, Ehab K. Emam, George E. Yacoub, Ashraf M. Salem

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Background: Obesity is an increasingly common problem in childhood. Childhood obesity is considered the main risk factor for the development of metabolic syndrome (MetS) (diabetes type 2, dyslipidemia, and hypertension). Recent studies estimated that among children with obesity 30-60% will develop MetS. Visceral fat thickness is a valuable predictor of the development of MetS. Computed tomography and dual-energy X-ray absorptiometry are the main techniques to assess visceral fat. However, they carry the risk of radiation exposure and are expensive procedures. Consequently, they are seldom used in the assessment of visceral fat in children. Some studies explored the potential of ultrasound as a substitute to assess visceral fat in the elderly and found promising results. Given the vulnerability of children to radiation exposure, we sought to evaluate ultrasound as a safer and more cost-efficient alternative for measuring visceral fat in obese children. Additionally, we assessed the correlation between visceral fat and obesity indicators such as insulin resistance. Methods: A cross-sectional study was conducted on 46 children with obesity (aged 6–16 years). Their visceral fat was evaluated by ultrasound. Subcutaneous fat thickness (SFT), i.e., the measurement from the skin-fat interface to the linea alba, and visceral fat thickness (VFT), i.e., the thickness from the linea alba to the aorta, were measured and correlated with anthropometric measures, fasting lipid profile, homeostatic model assessment for insulin resistance (HOMA-IR) and liver enzymes (ALT). Results: VFT assessed via ultrasound was found to strongly correlate with the BMI, HOMA-IR with AUC for VFT as a predictor of insulin resistance of 0.858 and cut off point of >2.98. VFT also correlates positively with serum triglycerides and serum ALT. VFT correlates negatively with HDL. Conclusions: Ultrasound, a safe and cost-efficient technique, could be a useful tool for measuring the abdominal fat thickness in children with obesity. Ultrasound-measured VFT could be an appropriate prognostic factor for insulin resistance, hypertriglyceridemia, and elevated liver enzymes in obese children.

Keywords: metabolic syndrome, pediatric obesity, sonography, visceral fat

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Authors: Safee Chaudhary, Mahnoor Naseer Gondal, Hira Anees Awan, Abdul Rehman, Ammar Arif, Risham Hussain, Huma Khawar, Zainab Arshad, Muhammad Faizyab Ali Chaudhary, Waleed Ahmed, Muhammad Umer Sultan, Bibi Amina, Salaar Khan, Muhammad Moaz Ahmad, Osama Shiraz Shah, Hadia Hameed, Muhammad Farooq Ahmad Butt, Muhammad Ahmad, Sameer Ahmed, Fayyaz Ahmed, Omer Ishaq, Waqar Nabi, Wim Vanderbauwhede, Bilal Wajid, Huma Shehwana, Muhammad Tariq, Amir Faisal

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Cancer is a manifestation of multifactorial deregulations in biomolecular pathways. These deregulations arise from the complex multi-scale interplay between cellular and extracellular factors. Such multifactorial aberrations at gene, protein, and extracellular scales need to be investigated systematically towards decoding the underlying mechanisms and orchestrating therapeutic interventions for patient treatment. In this work, we propose ‘TISON’, a next-generation web-based multiscale modeling platform for clinical systems oncology. TISON’s unique modeling abstraction allows a seamless coupling of information from biomolecular networks, cell decision circuits, extra-cellular environments, and tissue geometries. The platform can undertake multiscale sensitivity analysis towards in silico biomarker identification and drug evaluation on cellular phenotypes in user-defined tissue geometries. Furthermore, integration of cancer expression databases such as The Cancer Genome Atlas (TCGA) and Human Proteome Atlas (HPA) facilitates in the development of personalized therapeutics. TISON is the next-evolution of multiscale cancer modeling and simulation platforms and provides a ‘zero-code’ model development, simulation, and analysis environment for application in clinical settings.

Keywords: systems oncology, cancer systems biology, cancer therapeutics, personalized therapeutics, cancer modelling

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Authors: Fatemeh Abdollahi, Munn-Sann Lye, Jamshid Yazdani Charati, Mehran Zarghami

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Fathers are at risk of depression during the postpartum period. Some studies have been reported maternal depression is the key predictor of paternal postpartum depression (PPD). This study aimed to estimate the prevalence and predictors of parental PPD and its association with maternal PPD. In a cross-sectional study, via a stratified random and convenience sampling method, participants referring to health centers during 2-8 weeks postpartum were recruited from March to October 2017. Paternal PPD and its relation to maternal PPD and other related factors were assessed using multiple logistic regression. Participants were 591 literate couples who referred to Mazandaran province primary health centers during to study period. Couples were screened for depression using Edinburgh Postnatal Depression Scale (EPDS). Fathers provided information on socio-demographic characteristics, life events, neonatal stressor, perceived stress (Perceived Stress Scale), social support (Multidimensional Scale of Perceived Social Support), and general health status using General Health Questionnaire (GHQ) as well. Data on mothers ‘demographic characteristics and obstetrics factors was also gathered. Overall, 93 fathers (15.7%) and 188 mothers (31.8%) reported depressive symptoms above the cut-off EPDS score of 12. In the multiple logistic regression model, older age [OR=1.20, (95%CI: 1.05- 1.36)], maternal depressive symptoms [OR=1.15, (95%CI: 1.04-1.27)], higher GHQ scores [OR=1.21, (95%CI: 1.11-1.33)] and increased recent life events [OR=1.42, (95%CI: 1.01-1.2.00)] were related to paternal PPD. A significant inverse association was found between number of children and paternal PPD [OR=0.20, (95%CI: 0.07-0.53)]. Depressive symptoms, especially in first-time fathers following the birth of a child, are not uncommon. Maternal depressive symptoms and paternal well-being were strong predictors of parental PPD. Creating opportunities for men to access special health care services, parental education to help adapting to parenthood, screening programs, and psychiatric/psychosocial interventions to decrease the suffering of depression for both depressed parents are recommended.

Keywords: depression, men, postpartum, risk factors, women

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Authors: Shilu Deepa Thomas, P. Jayaprakash, Dorota Łazewska, Katarzyna Kieć-Kononowicz, B. Sadek

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A large body of evidence suggests the involvement of cognitive impairment, increased levels of inflammation and oxidative stress in the pathogenesis of autism spectrum disorder (ASD). ASD commonly coexists with psychiatric conditions like anxiety and cognitive challenges, and individuals with ASD exhibit significant levels of inflammation and immune system dysregulation. Previous Studies have identified elevated levels of pro-inflammatory markers such as IL-1β, IL-6, IL-2 and TNF-α, particularly in young children with ASD. The current therapeutic options for ASD show limited effectiveness, signifying the importance of exploring an efficient drugs to address the core symptoms. The role of histamine H3 receptors (H3Rs) in memory and the prospective role of H3R antagonists in pharmacological control of neurodegenerative disorders, e.g., ASD, is well-accepted. Hence, the effects of chronic systemic administration of H3R antagonist E159 on autistic-like repetitive behaviors, social deficits, memory and anxiety parameters, as well as neuroinflammation in Black and Tan BRachyury (BTBR) mice, were evaluated using Y maze, Barnes maze, self-grooming, open field and three chamber social test. E159 (2.5, 5 and 10 mg/kg, i.p.) dose-dependently ameliorated repetitive and compulsive behaviors by reducing the increased time spent in self-grooming and improved reduced spontaneous alternation in BTBR mice. Moreover, treatment with E159 attenuated disturbed anxiety levels and social deficits in tested male BTBR mice. Furthermore, E159 attenuated oxidative stress by significantly increasing GSH, CAT, and SOD and decreasing the increased levels of MDA in the cerebellum as well as the hippocampus. In addition, E159 decreased the elevated levels of proinflammatory cytokines (tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), and IL-6). The observed results show that H3R antagonists like E159 may represent a promising novel pharmacological strategy for the future treatment of ASD.

Keywords: histamine H3 receptors, antagonist E159, autism, behaviors, mice

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Authors: Mike Chia-Yu Huang

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China’s port facility construction projects in the Indian Ocean (IO) region, Gwadar Port and Djibouti Port projects in particular, have led to a heated debate among both Chinese and Western strategists over whether the country has literally been carrying out its “string of pearls” strategy, an alleged Chinese plan to challenge America’s military predominance in South Asia. Even though the Chinese government repeatedly denied the existence of such a strategy and highlighted the civilian/commercial nature of its port projects, it has significantly enhanced its strategic cooperation with littoral countries in the IO region since the “One Belt One Road” initiative was introduced by Chinese President Xi Jinping in 2013. Whether China does have a plan to expand its sphere of military influence westward concerns the balance of power in the IO region. If the answer is positive, the security environment there will be changed drastically. This paper argues that rather than simply copying the U.S. model of developing overseas military bases along the IO periphery, Beijing has been deliberating a more sophisticated plan for its physical presence there: creating a new set of “overseas strategic pivots.” These “pivots,” semi-military and semi-commercial in nature, are designed to help Beijing sustain its anti-piracy operations in the Gulf of Aden and serve as forward stations for the transportation of China’s imported energy and merchandise. They can support the Chinese Navy’s operations overseas but are not supposed to undertake face-to-face combat missions. This upgraded Chinese scheme can be identified as “string of pearls” strategy 2.0. Moreover, it is expected to help China deepen its roots in the IO region, implying that Beijing has to a large extent scratched its old diplomatic philosophy which highlighted the merits of non-interference and nonalignment. While a full-scale maritime confrontation between China and the U.S.-India security alliance is unlikely to be witnessed in the near future, an ambitious Chinese plan to step into the global maritime domain has been evidently shown.

Keywords: Chinese navy, Djibouti, Gwadar, Indian Ocean, string of pearls strategy

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Authors: Angelo Corallo, Maria Elena Latino, Marta Menegoli

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Agri-food value chain involves various stakeholders with different roles. All of them abide by national and international rules and leverage marketing strategies to advance their products. Food products and related processing phases carry with it a big mole of data that are often not used to inform final customer. Some data, if fittingly identified and used, can enhance the single company, and/or the all supply chain creates a math between marketing techniques and voluntary traceability strategies. Moreover, as of late, the world has seen buying-models’ modification: customer is careful on wellbeing and food quality. Food citizenship and food democracy was born, leveraging on transparency, sustainability and food information needs. Internet of Things (IoT) and Analytics, some of the innovative technologies of Industry 4.0, have a significant impact on market and will act as a main thrust towards a genuine ‘4.0 change’ for agriculture. But, realizing a traceability system is not simple because of the complexity of agri-food supply chain, a lot of actors involved, different business models, environmental variations impacting products and/or processes, and extraordinary climate changes. In order to give support to the company involved in a traceability path, starting from business model analysis and related business process a Framework to Manage Product Data in Agri-Food Supply Chain for Voluntary Traceability was conceived. Studying each process task and leveraging on modeling techniques lead to individuate information held by different actors during agri-food supply chain. IoT technologies for data collection and Analytics techniques for data processing supply information useful to increase the efficiency intra-company and competitiveness in the market. The whole information recovered can be shown through IT solutions and mobile application to made accessible to the company, the entire supply chain and the consumer with the view to guaranteeing transparency and quality.

Keywords: agriculture 4.0, agri-food suppy chain, industry 4.0, voluntary traceability

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Authors: Christina Hagen, Pragathi Kamale Gurmurthy, Thorsten M. Buzug

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CFD simulations are performed in the upper airway of a patient suffering from obstructive sleep apnea (OSA) that is a sleep related breathing disorder characterized by repetitive partial or complete closures of the upper airways. The simulations are aimed at getting a better understanding of the pathophysiological flow patterns in an OSA patient. The simulation is compared to medical data of a sleep endoscopic examination under sedation. A digital model consisting of surface triangles of the upper airway is extracted from the MR images by a region growing segmentation process and is followed by a careful manual refinement. The computational domain includes the nasal cavity with the nostrils as the inlet areas and the pharyngeal volume with an outlet underneath the larynx. At the nostrils a flat inflow velocity profile is prescribed by choosing the velocity such that a volume flow rate of 150 ml/s is reached. Behind the larynx at the outlet a pressure of -10 Pa is prescribed. The stationary incompressible Navier-Stokes equations are numerically solved using finite elements. A grid convergence study has been performed. The results show an amplification of the maximal velocity of about 2.5 times the inlet velocity at a constriction of the pharyngeal volume in the area of the tongue. It is the same region that also shows the highest pressure drop from about 5 Pa. This is in agreement with the sleep endoscopic examinations of the same patient under sedation showing complete contractions in the area of the tongue. CFD simulations can become a useful tool in the diagnosis and therapy of obstructive sleep apnea by giving insight into the patient’s individual fluid dynamical situation in the upper airways giving a better understanding of the disease where experimental measurements are not feasible. Within this study, it could been shown on one hand that constriction areas within the upper airway lead to a significant pressure drop and on the other hand a good agreement of the area of pressure drop and the area of contraction could be shown.

Keywords: biomedical engineering, obstructive sleep apnea, pharynx, upper airways

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Authors: María Dolores Caro, Eugenio M. Fedriani, Ángel F. Tenorio

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When lorries transport dangerous goods, there exist some legal stipulations in the European Union for assuring the security of the rest of road users as well as of those goods being transported. At this respect, lorry drivers cannot park in usual parking areas, because they must use parking areas with special conditions, including permanent supervision of security personnel. Moreover, drivers are compelled to satisfy additional regulations about resting and driving times, which involve in the practical possibility of reaching the suitable parking areas under these time parameters. The “European Agreement concerning the International Carriage of Dangerous Goods by Road” (ADR) is the basic regulation on transportation of dangerous goods imposed under the recommendations of the United Nations Economic Commission for Europe. Indeed, nowadays there are no enough parking areas adapted for dangerous goods and no complete study have suggested the best locations to build new areas or to adapt others already existing to provide the areas being necessary so that lorry drivers can follow all the regulations. The goal of this paper is to show how many additional parking areas should be built in the Iberian Peninsula to allow that lorry drivers may park in such areas under their restrictions in resting and driving time. To do so, we have modeled the problem via graph theory and we have applied a new efficient algorithm which determines an optimal solution for the problem of locating new parking areas to complement those already existing in the ADR for the Iberian Peninsula. The solution can be considered minimal since the number of additional parking areas returned by the algorithm is minimal in quantity. Obviously, graph theory is a natural way to model and solve the problem here proposed because we have considered as nodes: the already-existing parking areas, the loading-and-unloading locations and the bifurcations of roads; while each edge between two nodes represents the existence of a road between both nodes (the distance between nodes is the edge's weight). Except for bifurcations, all the nodes correspond to parking areas already existing and, hence, the problem corresponds to determining the additional nodes in the graph such that there are less up to 100 km between two nodes representing parking areas. (maximal distance allowed by the European regulations).

Keywords: dangerous goods, parking areas, Iberian peninsula, graph-based modeling

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Authors: Junjira Mahaboon, Anongnard Boonpak, Nattakarn Worrasan, Busma Kama, Mujalin Saikliang, Siripor Dankachatarn

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Rubber wood processing is one of the most important industries in southern Thailand. The process has several safety hazards for example unsafe wood cutting machine guarding, wood dust, noise, and heavy lifting. However, workers’ occupational health and safety measures to promote their behaviors are still limited. This quasi-experimental research was to determine factors affecting workers’ safety behaviors using theory of planned behavior after implementing job safety intervention program. The purposes were to (1) determine factors affecting workers’ behaviors and (2) to evaluate effectiveness of the intervention program. The sample of study was 66 workers from a rubber wood processing factory. Factors in the Theory of Planned Behavior model (TPB) were measured before and after the intervention. The factors of TPB included attitude towards behavior, subjective norm, perceived behavioral control, intention, and behavior. Firstly, Job Safety Analysis (JSA) was conducted and Safety Standard Operation Procedures (SSOP) were established. The questionnaire was also used to collect workers’ characteristics and TPB factors. Then, job safety intervention program to promote workers’ behavior according to SSOP were implemented for a four month period. The program included SSOP training, personal protective equipment use, and safety promotional campaign. After that, the TPB factors were again collected. Paired sample t-test and independent t-test were used to analyze the data. The result revealed that attitude towards behavior and intention increased significantly after the intervention at p<0.05. These factors also significantly determined the workers’ safety behavior according to SSOP at p<0.05. However, subjective norm, and perceived behavioral control were not significantly changed nor related to safety behaviors. In conclusion, attitude towards behavior and workers’ intention should be promoted to encourage workers’ safety behaviors. SSOP intervention program e.g. short meeting, safety training, and promotional campaign should be continuously implemented in a routine basis to improve workers’ behavior.

Keywords: job safety analysis, rubber wood processing workers, safety standard operation procedure, theory of planned behavior

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Authors: Chandrakant Gurav, Md Babar, Ajaykumar Asode

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Morphometric analysis is the first stage of any basin analysis. By using these morphometric parameters we give indirect information about the nature and relations of stream with other streams, Geology of the area, groundwater condition and tectonic history of the basin. In the present study, Yelganga, Shivbhadra and Kohilla rivers, tributaries of the Godavari River in Aurangabad district, Maharashtra, India are considered to compare and study their morphometric characters. The linear, areal and relief morphometric aspects of the sub-basins have been assessed and evaluated in GIS environment. For this study, ArcGIS 10.1 software has been used for delineating, digitizing and generating different thematic maps. The Survey of India (SOI) toposheets maps and Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) on resolution 30 m downloaded from United States Geological Survey (USGS) have been used for preparation of map and data generation. Geologically, the study area is covered by Central Deccan Volcanic Province (CDVP). It mainly consists of ‘aa’ type of basaltic lava flows of Late (upper) Cretaceous to Early (lower) Eocene age. The total geographical area of Yelganga, Shivbhadra and Kohilla river sub-basins are 185.5 sq. km., 142.6 sq. km and 122.3 sq. km. respectively The stream ordering method as suggested by the Strahler has been employed for present study and found that all the sub-basins are of 5th order streams. The average bifurcation ratio value of the sub-basins is below 5, indicates that there appears to be no strong structural control on drainage development, homogeneous nature of lithology and drainage network is in well-developed stage of erosion. The drainage density of Yelganga, Shivbhadra and Kohilla Sub-basins is 1.79 km/km2, 1.48 km/km2 and 1.89 km/km2 respectively and stream frequency is 1.94 streams/km2, 1.19 streams/km2 and 1.68 streams/km2 respectively, indicating semi-permeable sub-surface. Based on textural ratio values it indicates that the sub-basins have coarse texture. Shape parameters such as form factor ratio, circularity ratio and elongation ratio values shows that all three sub- basins are elongated in shape.

Keywords: GIS, Kohilla, morphometry, Shivbhadra, Yelganga

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