This article aims to re-examine the regional convergence hypothesis on income in Indonesia over the 2000-2017 period. By applying a non-linear dynamic factor model, this article tests the club ...convergence hypothesis using a novel dataset of income at the district level. The results show significant five convergence clubs in Indonesian districts' income dynamics, implying the persistence of income disparity problems across districts even after implementing the decentralization policy. The subsequent analysis reveals two appealing features regarding the convergence clubs. First, districts belonging to the same province tend to be in the same club, and second, districts with specific characteristics (i.e. big cities or natural resources-rich regions) dominate the highest income club. Overall, our findings suggest some insightful policy implications, including the importance of differentiated development policies across convergence clubs and inter-provincial development strategies.
The mechanical power, total rotor drag, and near-wake velocity of a 1:6 scale model (1.075 m diameter) of the US Department of Energy's Reference Model vertical-axis cross-flow turbine were measured ...experimentally in a towing tank, to provide a comprehensive open dataset for validating numerical models. Performance was measured for a range of tip speed ratios and at multiple Reynolds numbers by varying the rotor's angular velocity and tow carriage speed, respectively. A peak power coefficient CP = 0.37 and rotor drag coefficient CD = 0.84 were observed at a tip speed ratio λ0 = 3.1. A regime of weak linear Re-dependence of the power coefficient was observed above a turbine diameter Reynolds number ReD ≈ 106. The effects of support strut drag on turbine performance were investigated by covering the rotor's NACA 0021 struts with cylinders. As expected, this modification drastically reduced the rotor power coefficient. Strut drag losses were also measured for the NACA 0021 and cylindrical configurations with the rotor blades removed. For λ = λ0, wake velocity was measured at 1 m (x/D = 0.93) downstream. Mean velocity, turbulence kinetic energy, and mean kinetic energy transport were compared with results from a high solidity turbine acquired with the same test apparatus. Like the high solidity case, mean vertical advection was calculated to be the largest contributor to near-wake recovery. However, overall, lower levels of streamwise wake recovery were calculated for the RM2 case-a consequence of both the relatively low solidity and tapered blades reducing blade tip vortex shedding-responsible for mean vertical advection-and lower levels of turbulence caused by higher operating tip speed ratio and therefore reduced dynamic stall. Datasets, code for processing and visualization, and a CAD model of the turbine have been made publicly available.
Reinforced concrete beams reinforced with Fiber Reinforced Polymer (FRP) have several failure patterns, one of which is Concrete Cover Delamination. To prevent this failure, in this study, FRP U-Wrap ...was installed which was calculated using Strut and Tie Modelling (STM). The specimens of reinforced concrete beams with a length of 3300 mm, a width of 300 mm, and variations in height of 500, 600, and 700 mm were loaded with the two-point load method. Data collection and analysis was carried out using Digital Image Correlation, LVDT, strain gauge, and data logger. The bending behaviour reviewed in this study is ductility, crack pattern, type of failure, flexural capacity, and stiffness. In this study, the addition of U-Wrap did not have a significant effect on flexural behaviour when compared to beams without U-Wrap FRP. All beams experienced a failure pattern of FRP Debonding, so that the Concrete Cover Delamination did not occur.
Optimal and effective use of water in coastal areas is an essential aspect of plant growth in horticulture and the maintenance of water availability. It is necessary to monitor soil moisture ...continuously as the basis for watering time. However, it is hard for farmers to be in the field frequently to monitor the land humidity, even using an instrument to measure it at the site. It is needed a monitoring technique that can control the land humidity remotely. This paper presents a design of wireless soil moisture measurement based on the Internet of Things. We applied capacitive soil moisture sensors coupled with an ESP32 WIFI with a built-in 12-bit ADC function for reading analog sensor output and establishing a wireless connection to the internet network. The ESP32 was programmed using Arduino software. We made a web-based user interface and Google spreadsheet application using the Nodered which is a programmable IoT platform to show soil moisture and control the irrigation sprayers through the pump.
A fire damaged structure at the eastern part of Singapore was assessed. Some concrete spalling exposing corroded steel reinforcements were noted on the post tensioned concrete beam and reinforced ...concrete slab, raising a concern about the structural integrity of the overall floor. A comprehensive condition assessment was performed on the affected structural elements to determine the extent of the damage, which included some on-site destructive and non-destructive tests as well as some laboratory testing on the collected concrete and steel samples. Testing data revealed that the concrete was still in consistently good condition with the average residual compressive strength of 36.51MPa. Petrographic examinations suggested that the top 5mm of the concrete surface might be exposed to a temperature not more than 450o C. The steel reinforcement and post tension strands were found to be still in good condition as well. The findings of this assessment will then be used for further structural assessment to determine the most effective structural rehabilitation program.
Increasing global warming due to the uncontrolled use of fossil fuels has resulted in climate change which is currently a worldwide concern. Various efforts to use alternative energy have been made ...to overcome these problems, one of which is Pyrolysis technology to convert solid plastic waste into liquid fuel. Pyrolysis is a heating process, or the working principle is the same as distilling a raw material particle that will change shape from a solid to a gas and then passing through a condenser tube to cool down so that the steam will turn into a liquid. This process generally takes place at temperatures between 500-800°C. The pyrolysis process occurs with the help of heating from LPG gas. From the data obtained, further testing can be carried out on the physical and chemical properties of the pyrolysis oil to determine its characteristics. The physical properties tested included density and viscosity, while the chemical properties tested were the calorific value of the plastic pyrolysis process. The next step is to test the pyrolysis oil using WBT (Water Boiling Test) to determine the performance of the oil stove with pyrolysis oil as fuel. From the results of the efficiency of the stove from the pyrolysis of plastic oil, it is known that the largest input energy (Qin) is obtained in the pyrolysis oil without a catalyst in the first condenser of 2375,291 watts. The result of sensible heat (SH) of the most significant pyrolysis oil sample from pyrolysis without a catalyst in condenser one is 125.4 watts. The highest latent heat value was found in the pyrolysis of natural zeolite catalyst in condenser three at 231.752 watts, while the highest thermal efficiency value of pyrolysis using natural zeolite catalyst in condenser one was 28.39%. Natural zeolite catalysts reduce the liquid and solid products but increase gas products. The catalysts from pyrolysis oil have a darker color than without a catalyst. The cause is the reaction of the catalyst during the pyrolysis process.
Polymer concrete (PC) has been used to replace cement concrete when harsh service conditions exist. Polymers have a high carbon footprint when considering their life cycle analysis, and with ...increased climate change concerns and the need to reduce greenhouse gas emission, bio-based polymers could be used as a sustainable alternative binder to produce PC. This paper examines the development and characterization of a novel bio-polymer concrete (BPC) using bio-based polyurethane used as the binder in lieu of cement, modified with benzoic acid and carboxyl-functionalized multi-walled carbon nanotubes (MWCNTs). The mechanical performance, durability, microstructure, and chemical properties of BPC are investigated. Moreover, the effect of the addition of benzoic acid and MWCNTs on the properties of BPC is studied. The new BPC shows relatively low density, appreciable compressive strength between 20-30 MPa, good tensile strength of 4 MPa, and excellent durability resistance against aggressive environments. The new BPC has a low carbon footprint, 50% lower than ordinary Portland cement concrete, and can provide a sustainable concrete alternative in infrastructural applications.
This study aims to analyze and examine the influence of internal auditor certification, risk assessment, and the role of senior management on the effectiveness of cybersecurity for internal auditors ...who have experience in cybersecurity and information technology. This research method is a quantitative method, data analysis uses structural equation modeling (SEM) with SmartPLS 3.0 software tools. The population of this study is internal auditors who have experience in cybersecurity and information technology. The sample for this study was 480 respondents who were determined by the snowball sampling method. The research data was obtained from an online questionnaire which was distributed via social media. The questionnaire was designed using a Likert scale of 1 to 5. The stages of data analysis were validity test, reliability test and significance test. The results of this study indicate that internal auditor certification has a positive effect on cybersecurity effectiveness, risk assessment has a positive effect on cybersecurity effectiveness, and the role of senior management has a positive effect on cybersecurity effectiveness.
The discussion on regional income per capita convergence in Indonesia continues with an emphasis on whether regional per capita incomes tend to converge or diverge over the long run. This study ...evaluates the regional convergence hypothesis at the provincial level during the recent deindustrialization period 2001–2017 of Indonesia. First, the study examines the existence of convergence clubs in Indonesia using a recently assembled panel dataset. Results reveal four convergence clubs with particularly large income gaps, mostly arising from the top of the income distribution. Second, using an ordered logit model, the study examines the determinants of the convergence clubs. Result reveals that industrialization increases the probability of membership to a high‐income club.
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