bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mathematical model for calculating the equilibrium point of the refrigerant circuit
Authors: Daci A , Bundo J 
Published: December 2020

Abstract
Calculating the equilibrium point of the refrigerant circuit is one of the most important processes in the air treatment industry. Knowing the evaporation and condensation temperatures serves not only to obtain information on the performance and operating point of the compressor, but also to evaluate the performance of the machine under different climatic conditions. Often, the solution of the refrigerant circuit is accomplished by empirical methods or numerical methods such as the Newton – Raphson method or the medium method. Since the iteration time with these methods is unknown at the time of the iteration start, it is very important to implement algorithms that provide convergence information or not, and which can bring the system to a solution in the shortest possible time. The implementation of such a method would pave the way for simulating the behaviour of machines in the air treatment industry as an advanced verification process for real evaluation of machine performance. In this article, experimental results and mathematical model calculations will be presented and discussed.
Effect of the surface of the rough pipe on the fluid flow rate
Authors: Heriyani Oktarina , Mugisidi Dan , Hilmi Irfan 
Published: December 2020

Abstract
The concept of controlling the flow over the circular cylinder to reduce drag force and vibration caused by vortex flow has been explored by many researchers. One of them is by adding plates and helical strakes. However, the splitter plate is only useful for determining the direction of the current, while helical strakes increase drag force compared to cylinder forces of the same diameter. The problem that arises is that the surface roughness of the pipe will affect the characteristics of the fluid flow through it, so this study aims to analyze the characteristics and effects of fluid flow through the rough surface of the outer wall of the pipe by visualizing using Particle Image Velocity (PIV). The variation of pipe roughness used in this study is the roughness of sandpaper 100 and sandpaper 400 that encloses the pipe. The results showed that the addition of surface roughness resulted in the addition of the distance of the formation of vortex where the distance of 0.07 m was the longest distance from the bottom vortex formation on the pipe wrapped in sandpaper 100.
The effect of vortex generator on the approach value on forced draft type cooling tower
Authors: Heriyani Oktarina , Mugisidi Dan , Gunawan P H , Apriliana Putri Dwi 
Published: December 2020

Abstract
Cooling tower is needed right now in the context of efficiency and energy conventions for cooling circulation. The type of cooling tower used depends on the level of performance. One type of cooling tower used in this study is forced draft. Cooling tower in this study was added by a rectangular winglet generator vortex with the aim to increase the effectiveness of performance by reducing the value of the approach. This is because forced tower cooling draft on its utilization results in performance that is not commensurate with the costs incurred. The results obtained in this study are a comparison of the value of the forced draft cooling tower approach with the addition of a vortex generator and without the addition of a vortex generator. This research was conducted in the workshop and laboratory of Mechanical Engineering, Faculty of Engineering UHAMKA with stages: designing tools, making prototypes, assembling, and testing. Based on the results of the study it was found that the approach value obtained on cooling towers that use 0.86% lower than without a vortex generator.
Design of control and monitoring tools for electricity use loads, and home security systems with internet of things system based on Arduino Mega 2560
Authors: Budiyanto Setiyo , Medriavin Silalahi Lukman , Artadima Silaban Freddy , Siti Salamah Ketty , Rahayu Fajar , Iwan Wahyuddin M. , Andryana Septi 
Published: December 2020

Abstract
High economic growth makes the demand for comfortable and safe houses increasingly increase and the most obvious application of technology is technology with automated systems. With this technology, the use of electricity in homes can be monitored remotely. With the aim of optimizing and time efficiency, this research created a control system based on IoT system. The control system with the function of providing security and comfort for the homeowner and the people who live in it, because it can facilitate the work to be faster, effective and efficient. In this regard, in this research the title “Design of Controls and Monitoring of Electricity Loads, and Home Safety with IoT-based Arduino Mega 2560 Systems” is adopted. This application is used as consideration for someone applying the concept of smart homes and the Internet of Things in real life. The results of this research are testing the camera to process the results of taking pictures until the upload process is completed in storage on a computer that is made as a client server is 30 seconds and the entire system works properly and normally.
A Performance study of a single basin double slope solar still with 45˚ of glass-cover slope angle in Indonesia
Authors: Ni Ketut Caturwati , Yusuf Yusvardi , Arifin Zaenal , Fajar Komara Muhamad 
Published: December 2020

Abstract
Solar energy is a clean energy, pollution free and available in abundance that can be used directly for heating. Utilization of solar heat in the supply of clean water through distillation is very suitable for use in remote coastal and swampy areas. In this study the performance test of a single basin type solar distillation system with a double slope cover that has 45˚ slope angle is operated in Cilegon-Indonesia. With rare rainy conditions the average solar distillation efficiency reaches 34.3%. The formation of condensate at night is almost five times greater than during the daytime, because temperature of water in the basin is higher than the inner surface temperature of the glass-cover. Thus the use of material as a thermal energy storage when the intensity of radiation is high and releasing it into the water at night will help a lot to increase condensate production.
Particleboard characterization using sawdust from sengon wood, mahogany wood, bayur wood, and rice husk ash as composite fillers
Authors: Sunardi  , Lusiani Rina , Saefuloh Iman , Listijorini Erny , Eka Sumarna Anggit , Fawaid Moh. , Meliana Yenny 
Published: December 2020

AbstractBanten Province, Indonesia, has abundant natural resources. Waste from processing natural resources has not been utilized maximally. Several types of wood and plants used in this study were sengon (albizia Chinensis), bayur (pterspermum javanicum), mahogany (Swietenia mahogany) and rice husk ash as filler. The reference particleboard characteristics used are Indonesian Standard, SNI 03-2105-2006. The characteristics observed were pore diameter, hardness, impact toughness, flexural strength, and thickness development. The particleboard composition is 50% filler, 15% oil palm empty fruit bunches, 20% polyvinyl acetate adhesive, and 15% epoxy resin. The length of fiber used is 5 mm. This research shows that particleboard with mahogany filler has optimum characteristics, namely pore diameter 2.0288 nm, hardness 43 N/mm2, flexural strength 641.65 N/mm2, toughness 3.54 kJ/m2, and thickness swelling 1.20%.
Development of liquid smoke production process as a latex coagulant by utilizing a refrigeration machine
Authors: Sipahutar Riman , Kusuma Pratiwi Diah , Bizzy Irwin , Sofijan Armin , Hidayati Baiti 
Published: December 2020

Abstract
This study aims to obtain a method of producing liquid smoke as a latex freezing material using a pyrolysis reactor equipped with a counter flow condenser with a cold water cooling medium. The raw materials as local wisdom studied were coconut shells and oil palm shells, abundant in South Sumatra. The condensation process uses a shell and tube type heat exchanger with counter flow. The raw materials were pyrolyzed with time variations of 180, 240 and 300 minutes. The production of liquid smoke with a pyrolysis duration of 300 minutes has the highest yield values of 36,66% and 29,74%, respectively, for the the raw materials of oil palm shell and coconut shell. The average amounts of tar separated from liquid smoke in a settling tank are 8.13% and 8.08%, respectively, for raw materials of oil palm shell and coconut shell.
Design of machine element in alpha type stirling machine innovation design based on plastic waste
Authors: Satria Dhimas , Rosyadi Imron , Lusiani Rina , Listijorini Erny 
Published: December 2020

Abstract
One effort to overcome the use of fossil fuels is to use alternative energy sources, including plastic waste. Stirling engine is an external combustion engine that can utilize heat from various heat sources. In this research, an analysis of the design of the engine elements in the alpha-type Stirling engine design innovation is based on plastic waste, so it is expected to get the best and safest engine element design specifications. Based on the analysis results of calculations based on the Kwurmi method, it has been obtained the specifications of the design results of the engine elements are as follows: shaft design (length = 250 mm, diameter = 15 mm), post design ( length = 20 mm, width = 6 mm, thickness = 6 mm), pulley design (driver diameter = 100 mm, diameter driven = 60 mm), belt design (length = 987 mm, width = 30 mm, thickness = 5 mm), Stirling engine (power = 94.3 to 205.4 watts, engine speed = 300 to 1305 rpm, heat temperature = 623 ° k, cold temperature = 305 ° k, phase angle = 180 °, dimension = 580 mm × 250 mm × 700 mm, thermal efficiency = 0.51).
Design of pneumatic press machine for 250 page bundle book based on microcontroller arduino uno
Authors: Listijorini Erny , Haryadi  , Satria Dhimas , Sunardi  , Azizi Rahman Yusuf 
Published: December 2020

Abstract
Abstrak. Book is a collection of recorded papers that were put together by binding technique. Several types of binding techniques are carried out in the book bundle suppression stage. In this research, designing and building a book bundle press machine. The design starts with the demand for printing, house of quality, determination of specifications, functions, morphology, concepts to produce the best variant selection. The book bundle suppression system used follows the needs of printing with a semi-automatic system. This Research, a pneumatic press system with 250 pages capacity was controlled by Arduino UNO. This study discusses the selection and counting of pneumatic components and their framework, the selection of control components, simulating the results of component selection and control. From the design results obtained component costs of IDR 2,565,500.
Characterization of aluminium AC4B/Nano TiC composite with the variation of volume fraction of nano TiC reinforced through stir casting process
Authors: Adam M K , Syahrial A Z 
Published: December 2020

Abstract
Characterization of aluminium ac4b/nano tic composite with variation of volume fraction of nano TiC reinforced through stir casting process has been studied. The aluminium matrix used was aluminium alloy AC4B, which contain silicon and copper as its main alloy. Furthermore, the addition of Nano TiC into AC4B composite can increase the tensile strength, ductility, and toughness of AC4B composite by refining the dendrite structure of the α-Al phase and forming super saturated solid phase, θ (Al2Cu). In this study, AC4B/Nano TiC composite were made through stir casting with some variable parameters of Nano TiC reinforce composition of 0.25%, 0.3%, 0.35%, 0.4%, and 0.5% volume fraction to determine the optimum value of the mechanical properties of AC4B/Nano TiC composite. Stir casting process was chosen because it has several advantages, such as easy to use, flexible, and can be used to produce a large number of the products. It is known that AC4B/Nano TiC composite has optimum value of the mechanical properties when Nano TiC composition is 0,3% volume fraction with ultimate tensile strength of 132,31 MPa and the hardness of 55,18 HRB.
Design and analysis of new box frame for online motorcycle transportation
Authors: Christa Nugraha Avid , Ferliadi R , Nurma Amelia A , Sahroni T R 
Published: December 2020

Abstract
With the increasing needs and human’s creativity, accompanied by the development of technological knowledge from various things, one example is the development of online-based transportation. Transportation is a tool in the form of a vehicle that purpose is to move an item from one place to another. In the current era of globalization, there are several companies that develop their business through online transportation, in addition to the shuttle service there is also a delivery or pick up of food/goods quickly that can provide convenience for the community. This paper describes the redesign of the box that motorcyclists could use in online transportation. The design concept is designed more innovative to design models and materials used are also more practical & efficient in terms of time in use both in terms of installation and dismantling of the box, the aim is to answer the problems of online transportation at this time, which are not only in terms of efficiency but also ergonomics. The research was conducted by observing the existing problems, then brainstorming in ergonomic box design and then making 3D modelling using the inventor’s stress analysis method. to achieved a new innovative and ergonomic design for helping online transportation.
Magnetic force microscopy characterization of write field profiles of magnetic recording heads having a pole-tip protrusion
Authors: Phuagprapun A , Saengkaew K , Cheowanish I , Damrongsak B 
Published: December 2020

Abstract
Almost all previous studies on a thermal-induced pole-tip protrusion (PTP) were mainly focused on the extension of the main pole which in turn affects the flying height of magnetic recording heads and the hard-disk drive reliability. None was reported the PTP effect on a variation of write filed profiles that is directly related to the track width of the magnetic data. In this work, a method to characterize the magnetic field distribution of perpendicular recording heads with a protrusion in a pole-tip region was proposed and implemented. A magnetic head under test was biased with two current sources, one for the write coil and the other for the heater. The write field was then observed by magnetic force microscopy (MFM). MFM images were post-processed in order to investigate the field profiles. Two models of magnetic write heads having different heater designs were employed as test samples. We observed the variations in the area of the write field for the write heads having the protrusion of the pole tip, while the magnitude of the field intensity was almost constant.
Simulating Elliptic Low-pass Filter based on MOCCCII
Authors: Chomnak Nanan , Srisamranrungrueang Siradanai , Wongprommoon Natapong 
Published: December 2020

Abstract
Multiple output current-control current conveyer (MOCCCII) based Elliptic low-pass filter by using a simulating of RLC ladder prototype is presented in this work. The good performances of RLC ladder as well as low-sensitivity are inherited. Signal flow graph (SFG) method is applied to convert the RLC Elliptic ladder low-pass filter prototype to be the different function blocks. These function blocks can be realized by integrator and differentiator. Lossy integrator, lossless integrator and lossless differentiator realized from MOCCCII are straightforward replaced in SFG. Due to the tuning ability of MOCCCII, the proposed Elliptic low-pass filter can be tuned by adjusting the bias current (IB
). In addition, the frequency responses can be varied from 50kHz to 1MHz by tuning IB
from 1μA to 100 μA to prove the electronic tuning performance of the proposed filter. The simulation results are carried out by PSpice that the performances are totally agreed with the theory.
Modification fitness function of particle swarm optimization to improve the cluster centroid
Authors: Ratanavilisagul Chiabwoot 
Published: December 2020

Abstract
Clustering is a classification technique. The clustering is brought to create models. The model is applied with the new input data to identify the class of that data. The goal of clustering is finding the best cluster centroid. The process of searching the best cluster centroid can use Particle Swarm Optimization. Many researches use it and obtain good results. But, searching the best cluster centroid by PSO suffers the problem from calculating the fitness function, because the fitness function is calculated by distances from the cluster centroid to all data inputs. These fitness functions may lead to the bad cluster centroid. So, this paper proposed the fitness function is calculated by the results from classification. The results from classification can lead to the good cluster centroid and create a good model to apply with the new input data. The proposed technique is tested on seven datasets from the UCI Machine Learning Repository and gives more satisfied search results in comparison with PSOs for the data clustering problems.
Case Study of Data Exchange using Cross-Boundary Direct Interconnection between highly constrained Wireless Sensor Networks
Authors: Singhanat Krongboon , Panchareon Kantida 
Published: December 2020

Abstract
Internet of Things (IoT) connects multiple network entities together with different platforms and standards using the backbone network and Internet Protocol. However, some network interconnections may happen remotely at the edge of the network boundary between highly constrained platforms in absence of the connection with the backbone infrastructure. In this paper, we report the implementation of payload exchange between highly constrained multi-hop Wireless Sensor Networks (WSNs). The Constrained Application Protocol (CoAP) is accommodated by a native communication link using a payload fragmentation. The impacts of the hop distance and the fragmentation regarding the reliability and the latency are evaluated using a testbed showing less than 0.2 percent unsuccessful payload delivery.
Physicochemical properties, antioxidant activities, and sensory evaluation of pineapple peel biovinegar
Authors: Selvanathan Y , Masngut N 
Published: December 2020

Abstract
The objective of this study was to characterize a biovinegar (OPPB) produced from natural fermentation of pineapple peel. Physicochemical properties, antioxidant activities and sensory evaluation were investigated to compare its quality with apple cider vinegar (ACV) and dates vinegar (DV). The vinegars were evaluated for their scavenging activity towards 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical for the antioxidant activities. Physicochemical properties such as ascorbic acid, reducing sugar, acidity, acetic acid, ethanol, total soluble solid, pH and sucrose content were also determined. Consumer preferences and perception towards the biovinegar were carried out through a survey. The OPPB shows a comparable radical scavenging of 82 % and physicochemical properties such as acidity of 3.03 %, ascorbic acid of 1.43 mg equi. AA/100 mL sample, pH of 3.16, acetic acid of 0.61 %, ethanol of 1.03 %, sucrose of 4.0 g/100 g, reducing sugar of 3.18 % and total soluble solid content of 8.0°Brix with commercial vinegar (ACV and DV). Descriptive statistical test indicates that there were no significant differences in color intensity, sourness, sweetness, flavor, and aroma with the vinegars tested but OPPB was 56 % more preferred than ACV and DV by the respondents.
Characterization of gel beads used for immobilization of Chlorella vulgaris and enhancement its density for lipid production
Authors: Abu Sepian N R , Mat Yasin N H , Zainol N 
Published: December 2020

Abstract
The success of microalgae immobilized in gel beads for lipid production heavily relies on the characteristics of the matrices employed. This study aims to determine cell density and characteristics of immobilized Chlorella vulgaris cells that contributed to the viability of the cells within beads. The new combined matrices with volumetric ratios (Matrices:Microalgae) namely, (1) mixed matrices, SACMCCA (0.3:1) (2) SACA (0.3:1) (3) SACMC (1:1) were proposed in this study and (4) SA (1:1) (sodium alginate, SA; calcium alginate, CA; sodium carboxymethyl cellulose, CMC) as a control experiment. The size of the beads, membrane thickness and chemical compound of these beads were examined. The cell density demonstrated that SACMCCA beads presented the highest value of 1.72 ± 0.5 × 109 cells/mL and lipid yield (30.43 ± 0.30 %) compared to SACA (24.29 ± 0.50 %), SACMC (13.00 ± 0.60 %) and SA (6.71 ± 0.50 %). The characterization had provided important characteristics for a successful entrapment of Chlorella vulgaris. In addition, the combination of single matrices had improved the cell density and lipid production for future applications in the biofuel industry.
Free fatty acid formation in oil palm fruits during storage
Authors: Ahmad Nizam A F , Muthiyah K , Mahmud M S 
Published: December 2020

Abstract
Free fatty acids (FFAs) are derived from the undesired hydrolysis reaction of glycerides with the presence of lipase, and quantified as acid value for crude palm oil (CPO) grading. Since FFA content is directly proportional to time, duration from harvest to sterilization of fruits is not more than a day. This paper reports peculiar trend of FFA formation over time when the analysis of FFA was carried out differently. Analysis results of FFA and glyceride contents by timely picking the fruitlets (R-fruit) from fresh fruit bunch (FFB) were compared with the fruitlets from spikelet (S-fruit) that were initially removed all for 7 days. The results showed that the increment of FFA content of the latter was 10 hour faster. This implies that the fruitlets from spikelet resemble the detached fruits which having higher rate of FFA formation compared to the fruitlets that attached to FFB. By using SigmaPlot, the graphs of R-fruit and S-fruit were best fitted into damped sine, 5 parameter with linear and rational with 4 parameters respectively. Nevertheless, lower R2 value was obtained for the fruitlets from readily-removed spikelet compared to the fruitlets from FFB, indicating that other factors might have also affected the formation of FFA.