Rancang Bangun Sistem Pengendali Irigasi Berbasis Analisis Evapotranspirasi Dengan Kontroler On/off

Food is a basic requirement for life so that the availability is absolutely necessary of all time. The need for food continues to increase along with the growth of population. While the source of the water decreases and becomes scarce during the dry season. So the real action to improve agricultural products is indispensable. One way to meet the water needs of plants properly is to calculate the crop evapotranspiration with Penman-Monteith equation. While the tools to realize the results of these calculations is to create an irrigation controllers system. Irrigation control system that is made has inputs from weather environment obtained with the sensor and has an output valve to drain the water. The main parameters are used as input air temperature, wind speed, relative humidity, and solar radiation. All parameters acquired digitally except solar radiation, solar radiation are acquired from correlation shaping using artificial neural networks algorithm with input temperature and light intensity. The type of valve used is on/off with controller type used is on/off. This study divided into three steps, the first steps is modeling with matlab software. Second, the design of simulation tools with results shown on oscilloscope. Third, the design of the controller device. Artificial neural networks are used feedforward structure with 2 hidden layer. The amount of the first layer size is 15x2 matrix and The amount of the second layer is 1, which produces a fairly good prediction, i.e., with the largest error of 1.13%. The simulation results of the control system on/off produces an error of 1.8% while the application of control system on/off produces an error of 2.20%

Determination of Operation Condition and Product Dimension Accuracy Optimization of Filament Deposition Modelling on Layer Manufacturing Application

Layer manufacturing process has proven as a process that can produce a high complexity mechanical part.Now, Improvement of LM methods continuously conduct that is aimed to increase precessions and efficiency of theseprocesses. Pressure filament deposition modelling is a form of layer manufacturing process that is designed to produce aplastic part with controlling its semisolid phase. In this research, the equipment of filament depositor is designed andtested to make the product filament deposition. With operation condition observation, the optimal temperature andpressure of deposition process was determined. These experiments used PVC as crystalline material and polypropyleneas amorphous material. To optimize this process, the tensile strength and density test were conducted. The shape oftensile test specimens is based on ASTM 638 standard and made in 3 orientations deposition path, namely: in 0 degree,45 degree and 90 degree from load force axis. To found the most accurate dimension, controlling the time delay,temperature of build part, feeding speed and variation deposition path was conducted. The results of experiments showthat the filament deposition method can only be applied for amorphous material in which it has a semisolid phase. Fromthe tensile strength test, the binding strength among filaments is 0.5 kg/mm2, 20% of the tensile strength of filament.And the density of a sample product, which used the filament diameter of 0.8 mm, is 0.7668 g/cm3. Accuracy of productdimension can be increased by: controlling time delay in location where the motion orientation of hopper filament ischanged and controlling temperature of build part surface

DETERMINATION OF OPERATION CONDITION AND PRODUCT DIMENSION ACCURACY OPTIMIZATION OF FILAMENT DEPOSITION MODELLING ON LAYER MANUFACTURING APPLICATION

Layer manufacturing process has proven as a process that can produce a high complexity mechanical part.Now, Improvement of LM methods continuously conduct that is aimed to increase precessions and efficiency of theseprocesses. Pressure filament deposition modelling is a form of layer manufacturing process that is designed to produce aplastic part with controlling its semisolid phase. In this research, the equipment of filament depositor is designed andtested to make the product filament deposition. With operation condition observation, the optimal temperature andpressure of deposition process was determined. These experiments used PVC as crystalline material and polypropyleneas amorphous material. To optimize this process, the tensile strength and density test were conducted. The shape oftensile test specimens is based on ASTM 638 standard and made in 3 orientations deposition path, namely: in 0 degree,45 degree and 90 degree from load force axis. To found the most accurate dimension, controlling the time delay,temperature of build part, feeding speed and variation deposition path was conducted. The results of experiments showthat the filament deposition method can only be applied for amorphous material in which it has a semisolid phase. Fromthe tensile strength test, the binding strength among filaments is 0.5 kg/mm2, 20% of the tensile strength of filament.And the density of a sample product, which used the filament diameter of 0.8 mm, is 0.7668 g/cm3. Accuracy of productdimension can be increased by: controlling time delay in location where the motion orientation of hopper filament ischanged and controlling temperature of build part surface.Keywords: semi solid phase, deposition, filament flow-rat

Predictors of Acceptance and Rejection of Online Peer Support Groups as a Digital Wellbeing Tool

© 2020, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG. Digital media usage can be problematic; exhibiting symptoms of behavioural addiction such as mood modification, tolerance, conflict, salience, withdrawal symptoms and relapse. Google Digital Wellbeing and Apple Screen Time are examples of an emerging family of tools to help people have a healthier and more conscious relationship with technology. Peer support groups is a known technique for behaviour change and relapse prevention. It can be facilitated online, especially with advanced social networking techniques. Elements of peer support groups are being already embedded in digital wellbeing tools, e.g. peer comparisons, peer commitments, collective usage limit-setting and family time. However, there is a lack of research about the factors influencing people acceptance and rejection of online peer support groups to enhance digital wellbeing. Previous work has qualitatively explored the acceptance and rejection factors to join and participate in such groups. In this paper, we quantitatively study the relationship between culture, personality, self-control, gender, willingness to join the groups and perception of their usefulness, on such acceptance and rejection factors. The qualitative phase included two focus groups and 16 interviews while the quantitative phase consisted of a survey (215 participants). We found a greater number of significant models to predict rejection factors than acceptance factors, although in all cases the amount of variance explained by the models was relatively small. This demonstrates the need to design and, also, introduce such technique in a contextualised and personalised style to avoid rejection and reactance

Development of a p84/zcc composite carbon membrane for gas separation of h2/co2 and h2/ch4

Hydrogen (H2) has become one of the promising alternative clean energy resources. Membrane technology is a potential method for hydrogen separation or production. This study aims to develop a new carbon membrane for hydrogen separation or production. Moreover, the permeation behavior of H2, CO2, and CH4 through a hollow fiber composite carbon membrane derived from P84 co-polyimide and with incorporation of zeolite composite carbon (ZCC) was also examined. ZCC was synthesized via the impregnation method of sucrose into zeolite-Y pores, followed by carbonization at 800 °C. Thus, this filler has a high surface area, high microporosity, ordered pore structure, and low hydrophilicity. The presence of zeolites in ZCC is predicted to increase certain gases' affinity for the membrane. Various heating rates (1-5 °C/min) were applied during pyrolysis to understand the effect of the heating rate on the pore structure and H2/CO2 and H2/CH4 gas separation performance. Moreover, gas permeation was evaluated at various temperatures (298-373 K) to study the thermodynamic aspect of the process. A characteristic graphite peak was detected at 2θ ∼44° in all carbon samples. Scanning electron microscopy (SEM) observations revealed the void-free surface and the asymmetric structure of the carbon membranes. During the permeation test, it was found that gas permeation through the membrane was significantly affected by the temperature of the separation process. The highest permeability of H2, CO2, and CH4 was detected on the composite carbon membrane at a 3 °C/min heating rate with a permeation temperature of 373 K. The thermodynamic study shows that CO2 and H2 have lower activation energies compared to CH4. The transport mechanism of the membrane involved adsorption and activated surface diffusion. The permeation temperature has a large impact on the transport of small penetrants in the carbon matrix

Online Peer Support Groups to Combat Digital Addiction: User Acceptance and Rejection Factors

The obsessive usage of digital media may exhibit symptoms traditionally associated with behavioural addictions such as mood modification, salience, tolerance and conflict. The educational methods, interventions, and treatments available to prevent or control such a digital addiction are, currently, very limited. Digital Addiction (DA) is yet not formally recognised as a mental disorder by the Diagnostic and Statistical Manual of Mental Disorders. Recently, in 2018, the World Health Organization recognised gaming disorder. Fortunately, the nature of digital media can also help the hosting of methods and mechanics to combat DA, e.g. in the monitoring of online usage and enabling individuals to stay in control of it. One of the techniques proposed in the literature is Online Peer Groups platforms, towards allowing people to form a group and provide peer support to control and regulate their usage, collectively. Online peer support groups are meant to provide peer support, counselling, motivational and learning environment, and ambivalence reduction through sharing and hope installation. However, there is a lack of research about the factors influencing people with DA to accept or reject online peer support groups. In this work, we conduct user studies and explore the acceptance and rejection factors to join and participate in such DA regulation and relapse prevention method. This will help to design and introduce the method and increase its adoption

Internet addiction and its psychosocial risks (depression, anxiety, stress and loneliness) among Iranian adolescents and young adults: a structural equation model in a cross-sectional study

Internet addiction has become an increasingly researched area in many Westernized countries. However, there has been little research in developing countries such as Iran, and when research has been conducted, it has typically utilized small samples. This study investigated the relationship of Internet addiction with stress, depression, anxiety, and loneliness in 1,052 Iranian adolescents and young adults. The participants were randomly selected to complete a battery of psychometrically validated instruments including the Internet Addiction Test, Depression Anxiety Stress Scale, and the Loneliness Scale. Structural equation modeling and Pearson correlation coefficients were used to determine the relationship between Internet addiction and psychological impairments (depression, anxiety, stress and loneliness). Pearson correlation, path analysis, multivariate analysis of variance (MANOVA), and t-tests were used to analyze the data. Results showed that Internet addiction is a predictor of stress, depression, anxiety, and loneliness. Findings further indicated that addictive Internet use is gender sensitive and that the risk of Internet addiction is higher in males than in females. The results showed that male Internet addicts differed significantly from females in terms of depression, anxiety, stress, and loneliness. The implications of these results are discussed

Towards an understanding of internet-based problem shopping behaviour: the concept of online shopping addiction and its proposed predictors

Abstract Background Compulsive and addictive forms of consumption and buying behaviour have been researched in both business and medical literature. Shopping enabled via the Internet now introduces new features to the shopping experience that translate to positive benefits for the shopper. Evidence now suggests that this new shopping experience may lead to problematic online shopping behaviour. This paper provides a theoretical review of the literature relevant to online shopping addiction (OSA). Based on this selective review, a conceptual model of OSA is presented. Method The selective review of the literature draws on searches within databases relevant to both clinical and consumer behaviour literature including EBSCO, ABI Pro-Quest, Web of Science — Social Citations Index, Medline, PsycINFO and Pubmed. The article reviews current thinking on problematic, and specifically addictive, behaviour in relation to online shopping. Results The review of the literature enables the extension of existing knowledge into the Internet-context. A conceptual model of OSA is developed with theoretical support provided for the inclusion of 7 predictor variables: low self-esteem, low self-regulation; negative emotional state; enjoyment; female gender; social anonymity and cognitive overload. The construct of OSA is defined and six component criteria of OSA are proposed based on established technological addiction criteria. Conclusions Current Internet-based shopping experiences may trigger problematic behaviours which can be classified on a spectrum which at the extreme end incorporates OSA. The development of a conceptual model provides a basis for the future measurement and testing of proposed predictor variables and the outcome variable OSA

Validation and psychometric analysis of the Internet Addiction Test in Spanish among college students

BACKGROUND: The wide use of the Internet in the workplace, academic or social field, can have an impact on daily life. One of the most used questionnaires worldwide to analyse these problems is the Internet Addiction Test (IAT). Our aim was to validate a Spanish version of the IAT and analyse its psychometric properties. METHODS: Population of study were college students participating in the uniHcos project (Universities of Granada, Huelva, Jaén, León, Salamanca, and Vigo). The questionnaire was translated and back-translated by two native English speakers. Reliability of scores was analysed using Pearson's correlation coefficient and agreement was analysed using the Bland-Altman and Kappa techniques. Test dimensions were analysed by exploratory and confirmatory factor analysis. RESULTS: The reliability of scores was good (r = 0.899, Kappa = 0.650 and mean difference using Bland-Altman = -3.5). The psychometric assessment identified two factors (Emotional Investment; Performance and Time Management) which explained 55 % of the variance (total internal consistency of 0.91) and only 19 items. The confirmatory analysis showed an acceptable goodness of fit, especially when items 6 and 8 were related (RMSEA = 0.07 90%IC = 0.06 - 0.08; WRMR = 1.01, CFI = 0.96; TLI = 0.95). The two dimensions were negatively correlated with age and positively correlated with time spent online, especially for the purposes of leisure and entertainment. DISCUSSION: The results show good reliability and psychometric properties of the Spanish version of IAT with a two-dimensional solution. This result is partially in concordance with previous validations of the IAT in other languages that have found uni- and multi-dimensional solutions using different methodologies. Moreover, we want to highlight the possibility that some item of this questionnaire is outdated due to the technological and lifestyles changes and should be not taken into account. CONCLUSION: The reliability and psychometric properties obtained in this study support the conclusion that this Spanish short version of the IAT represents a useful tool for the analysis of problems arising from misuse of the Internet

Portuguese validation of the Internet Addiction Test: An empirical study

Abstract Background and aims Research into Internet addiction (IA) has increased greatly over the last decade. Despite its various definitions and general lack of consensus regarding its conceptualisation amongst researchers, instruments for measuring this phenomenon have proliferated in a number of countries. There has been little research on IA in Portugal and this may be partly due to the absence of standardised measurement tools for assessing IA. Methods This study attempted to address this issue by adapting a Portuguese version of the Internet Addiction Test (IAT) via a translation-back translation process and Confirmatory Factor Analysis in a sample of 593 Portuguese students that completed a Portuguese version of the IAT along with questions related to socio-demographic variables. Results The findings suggested that the IAT appears to be a valid and reliable instrument for measuring IA among Portuguese young adults as demonstrated by its satisfactory psychometric properties. However, the present findings also suggest the need to reword and update some of the IAT's items. Prevalence of IA found in the sample was 1.2% and is discussed alongside findings relating to socio-demographic correlates. Limitations and implications of the present study are also discussed. Conclusions The present study calls for a reflection of the IAT while also contributing to a better understanding of the basic aspects of IA in the Portuguese community since many health practitioners are starting to realise that Internet use may pose a risk for some individuals