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The accumulation in large volume of solid waste in the area of TPA Mandung is creating a new serious problem since the leachate is extremely increasing. The spill drastically contaminates the groundwater and the surrounding environment because the wastewater treatment plant isn’t working on full capacity. Based on those facts, it is necessary to start researching on how the leachate influences the soil characteristics, and how to get the soil to provide a proper filtration. The samples of soil and the leachate from TPA Mandung have, at first, been collected; soil properties have been physically and mechanically tested, while the leachate characteristics have been determined from the parameters of the contained substances. The leachate filtration was performed simultaneously with a hydraulic conductivity test simply varying its height from 7 cm, 9 cm, and 11 cm. The water drained from the hydraulic conductivity test has been reexamined to determine the changes in the leachate parameters after passing through the soil. The K value (hydraulic conductivity coefficient) in the soil hydraulic conductivity test sampled with height 11 cm, 9 cm, 7 cm, were respectively 0.000050 cm/sec, 0.000062 cm/sec, and 0.000065 cm/sec. The results showed a decrease in the coefficient of hydraulic conductivity along with the addition of leachate and the variation in sample height. The leachate in TPA Mandung before and after filtration had COD, BOD5, TSS, TDS and oil levels that exceeded the permitted threshold according to Regulation of Minister of Environment No. 5 of2014 concerning Wastewater Quality Standard.

The alternative electric vehicle for delivery (E-Trike) is a developing three-wheel electric vehicle for goods delivery. Small size and its three-wheel mobility are required for flexible manoeuvrability on urban space due to traffic, parking and alley road. In this study, three different Alpha frames (Alpha-0, Alpha-1, and Alpha-2) of E-Trike vehicle are analysed using numerical simulation LS-DYNA. This study is conducted to obtain the modal response E-Trike vehicle. Eigenvalues of dynamics properties are investigated to avoid a resonance on excitation frequency. LS-DYNA implicit simulation used for simulating quadrangular shell element for the surface geometry of the frames. Boundary conditions are applied to the steering and suspension joints represent the real field. The result shows the amplitudes and the natural frequencies of Alpha frames. Bending mode and torsion mode can be determined. Based on the simulation, there is a pattern of vibration modes. Alpha-2 which is the latest version of three configurations has better response on vibration modes. There is about 3% reduction of vibration amplitude at Alpha-2 than Alpha-0 and Alpha-1. Natural frequency response for each mode occurs at similar range. Furthermore, a shifted natural frequency of Alpha-2 combination mode occurs due to addition of the stretched frame.

This paper aims to demonstrate a measurement method of pressure wave speed in stainless-steel pipe filled with water caused by water hammer phenomenon. The pressure wave is generated using a self-developed drop impact testing equipment. An impactor is dropped to collide a buffer which then induces the water hammer phenomenon. The generated pressure and its propagation speed in the water are carefully measured here. Pressure measurement is conducted by a pressure transducer, while pressure wave speed is measured by two methods, which utilize peak time of the pressure recorded by pressure transducer and peak time of strains recorded by two strain gages positioned in a different location. These strain gages are oriented to the circumferential direction of the pipe. Measurement result shows that at 1.5 m height, impact pressure of between 0.86 to 1.16 MPa and wave velocity of 1250 m/s were obtained. From the experimental results, the characteristic of pressure wave in the water was able to be observed.

Traffic jams are a common phenomenon in Indonesia’s big cities due to the proliferation of private vehicles. The resulting air pollution directly threatens public health and urban quality of life. This research is to identify and analyze air pollution levels and forecast the potential to improve air quality by developing mass public transportation. This research employs the dust sampler method to measure the air pollution levels and calculate traffic volume, while the simulation method is used to analyze the data. The results show that the air pollution levels detected exceed the air quality thresholds established by regulations in the Decision by the Minister of Health and Environment. Traffic jam levels indicated by the Degree of Saturation (SD) were determined to be, on average, > 0.75. The simulation results show that by changing modes of transportation traffic jam levels decrease, ranging from 0.2201 to 0.291(DS), and air pollution decreases. Specifically, nitrogen oxides (NOx) are reduced by 48.19 %; sulfur dioxide (SO2) is reduced by 51.77 %; particulate matter (PM) is reduced by 29.86%; lead (Pb) is reduced by 52.22%; and carbon monoxide (CO) is reduced by 52.15%. This research suggests the mass public transportation planning should be implemented.

Material transfer is one of the most important activities in the production process activities and has a close relationship with the design of the layout of production facilities. A manufacturing company engaged in the manufacture and assembly of machine spare parts at the oil palm plant constraints in terms of material handling so that the decline in utility of the production floor layout and the increasing cost of moving raw materials. To improve the utility on the production floor using group technology method that is Rank Order Clustering (ROC) and Similarity Coefficient (SC). From the result of matrix rank calculation in pairs or between machines then SC method is the best layout design with decreasing material displacement moment by 56,86%. And to improve the layout of facilities on the production floor using BLOCPLAN algorithm that is the value of the degree of Adjency Score of 0.5317. This proposed layout provides a smaller displacement moment so as to shorten the processing time of all parts by 338 minutes and increase utility on the production floor.

The existence of a city is very important in civilization. It is notonly as a physical habitat where a group of human lives together but alsoas a place where a community develops and becomes a noble andprosperous society. Islamic community creates a city as a means to create aphysical, economic, social and religious environment. This paper discussedhow the settlement of a city develops Islamic civilizations, from the periodof the Prophet in Madinah, then spread to Arab, Africa, and Asian regions, bringing significant roles for the community. Istanbul, one of the importantcities in Islamic civilization, grew with a combination of many traditions, from Hellenic, Byzans, Persia and later Islam; these traditions thenunderwent fusion as basic thinking to develop the city. This thinking wasimplemented in many ways, from the planning conceptions for thestructure of the city, the unity of the main components of the city (palace, mosque, square and market), the settlement configurations, until theaesthetics of the city expressions.

Batik is one of Indonesian cultural heritage that confirmed by United Nations of Educational, Scientific, and Cultural Organization (UNESCO) on October 2009. This legal confirmation improves the number of batik industry from many regions based its local unique characteristic. The increasing number of batik SMEs in Indonesia requires a strategy that can create competitive advantage. This strategy can be done by reducing production waste. One of Indonesian batik SMEs is SME Batik CM located in Yogyakarta. There are several problems that occur in the industry, i.e. length of the production process, spots on Batik and excessive raw materials inventory. Based on that problems, this research is done by applying lean manufacturing concept using value stream mapping (VSM) method to evaluate production wastes. Based on the result of the research, there are seven types of production waste: overproduction (9,62%), inventory (17,3%), defect (23,08%), motion (9,62%), transportation (9,62%), Over processing (9,62%) and waiting (21,15%). Process improvement is done to reduce the highest waste, defect, using quality filter mapping (QFM).

Security issues are an important part of everyday life. A vital link in security chain is the identification of users who will enter the room. This paper describes the prototype of a secured room access control system based on face recognition. The system comprises a webcam to detect faces and a solenoid door lock for accessing the room. Every user detected by the webcam will be checked for compatibility with the database in the system. If the user has access rights then the solenoid door lock will open and the user can enter the room. Otherwise, the data will be sent to the master user via Android-based smartphone that installed certain applications. If the user is recognized by the master user, then the solenoid door lock will be opened through the signal sent from the smartphone. However, if the user is not recognized, then the buzzer will alert. The main control circuit on this system is Raspberry pi. The software used is OpenCV Library which is useful to display and process the image produced by webcam. In this paper, we employ Haar Cascade Classifier in an image processing of user face to render the face detection with high accuracy.

The Failure Modes and Effects Analysis (FMEA) method has been widely recognized as a tool that systematically identifies the consequences and failures of the system or process, and reduces or eliminates the chances of the failure. This study applies that method to evaluate the causes of failure in the use of sugarcane machine that have been designed in the previous studies. FMEA approach anticipated the failures at the design stage, so that a more reliable and ergonomic design can be produced for future sugarcane machine. The potential failure identified from the machine consists of capacity issues, machine maintenance, preliminary treatment, and procedures of use. The study found that capacity issues are the priority problems that cause the machine failure. Then, this study proposed some actions to reduce the risk priority number (RPN) on 12 failures.

Transportation plays a vital role in palm oil industry supply process because it provides the opportunity to continuously create supply operational efficiency and improve supply chain performance. The objective of this paper is to optimize route transportation process to represent a capacitated shortest route problem in palm oil FFB. A metaheuristic method based on genetic algorithm is designed as a model solution for the mathematical model. A case study in PTPN III Indonesia is presented to test the model effectivity and efficiency. The results indicate that the proposed metaheuristic method can find a better route rather than random method used by the company.

Globally, there is growing interest in microalgae as production organisms. Microalgae contain lipids (oil), proteins and carbohydrates (sugars), and, especially marine algae have been used as food and feed for centuries. Recently, production cost reduction related to the supply of growth nutrients is necessary to make it profitable. Therefore, utilization of molasses, a byproduct of sugar production, as the natural carbon, macronutrients, and micronutrients sources can be helpful. The analysis showed that the content of sucrose, glucose, fructose, potassium, zinc, and magnesium was 68.4% w/w, 18.5% w/w, and 13.1% w/w, 5.5% w/w, 3.91 ppm, and 1,370 ppm respectively. This work aimed to determine the effect of molasses addition to the physio-chemical properties of multi-culture species of microalgae isolated from southern Java coastal region in Indonesia grown under mixotrophic culture. The cultivation in this work used medium which was self-formulated by the authors consisting of NaNO3 (5 mL/L), H3BO3 (1 mL/L), EDTA (1 mL/L), N2H2PO4 (5 mL/L), FeSO4 (1 mL/L), MgSO4 (1 mL/L), NaCl (1 mL/L), micronutrients (1 mL/L), vitamin B1 (1 mL/L), and vitamin B12 (1 mL/L) in 500 mL of water. The medium will be treated to have molasses concentration of 0.05% v/v, 0.15% v/v, 0.25% v/v, 0.35% v/v, and 0.45% v/v.

Biodiesel production from microalgae is one of the solution of the future energy problem, but its production cost is still high. One of the costly stages of this process is the lipid extraction process. It can be reduced by microalgae cell disruption. One of the mechanical method to cell disruption with the lowest energy requirement is hydrodynamic cavitation. This aim of this study is to evaluate the distribution coefficient and the mass transfer coefficient value of lipid extraction of Nannochloropsis sp. assisted by hydrodynamic cavitation and compare with conventional extraction. The hydrodynamic cavitation extraction was done at 34 °C, 1 atm. The conventional extraction was done at 34 °C, 1 atm with stirring speed 260 and 1000 rpm. The experimental result shows that the distribution coefficient dependent on the temperature with the values for 50, 44, 38 and 34 °C were 0.502, 0.394, 0.349, and 0.314 respectively. And it was according to Van’ Hoff equation with the values of ΔH° was 20.718 kJ/mol and ΔS° was 58.05 J/mol/K. The hydrodynamic cavitation extraction was faster than conventional. The mass transfer coefficient values for hydrodynamic cavitation, conventional 260 rpm and 1000 rpm were 7.373, 0.534 and 0.121 1/s respectively.

Computer mediated communication are the communication activities using technology which have rapidly in progress. Communication interactive activities nowadays has no longer only involving person to person but mediated by technology, and have been done in many fields including in education and teaching activity. In this study, presentation media based on cloud's infrastructure designed to replace face to face or in class lectures. In addition, the presentation will allow media data storage indefinitely, and accessible wherever and anytime. This is in line with the concept of student center learning where students were encouraged to more active in the lecture activities. The purpose of this research is making or designing a presentation model based on cloud‘s infrastructure. This research is using research and development method which is consists of four stages, where the first phase is composing the concept of media presentation design. The second phase are choosing the subject that will be designed as the subject of presentation. The third stage is designing presentation model. And the fourth phase is collecting materials of the subject that will be presented by each lecturer.

At the time, development of technology and system information provide an idea in project management information system. One of industrial which growing up in Indonesia is Engineering Procurement and Construction (EPC), in this case required a system to facilitate between all stakeholders to improve their performance. Progress report on the project that was created approach using earn value analysis (EVA) system which considered cost and schedule of work as well as a productivity performance index of workers. In addition, project progress was formed by comparing between plans and realization of work which has projected since of the beginning of the project. The result on the system was provides information of progress every time through on the dashboard page input by the user. The first step of making a report on the system, started which input the project name and then step over to make the detailed work in each department or discipline in project. The data obtained were then processed by the project control team to provide information of progress project status against the top management. The establishment of information system can be stored and accessed online by all user who have been classified in the system. That information can be integrated between the top management to take a decision against the ongoing project.

In the last decade, several hybrid methods combining the finite element and meshfree methods have been proposed for solving elasticity problems. Among these methods, a novel quadrilateral four-node element with continuous nodal stress (Q4-CNS) is of our interest. In this method, the shape functions are constructed using the combination of the ‘non-conforming’ shape functions for the Kirchhoff’s plate rectangular element and the shape functions obtained using an orthonormalized and constrained least-squares method. The key advantage of the Q4-CNS element is that it provides the continuity of the gradients at the element nodes so that the global gradient fields are smooth and highly accurate. This paper presents a numerical study on the accuracy and convergence of the Q4-CNS interpolation and its gradients in surface fitting problems. Several functions of two variables were employed to examine the accuracy and convergence. Furthermore, the consistency property of the Q4-CNS interpolation was also examined. The results show that the Q4-CNS interpolation possess a bi-linier order of consistency even in a distorted mesh. The Q4-CNS gives highly accurate surface fittings and possess excellent convergence characteristics. The accuracy and convergence rates are better than those of the standard Q4 element.

The importance of machine maintenance has been gradually recognized especially with the great attention in industrial sector. A company was named M is a manufacturing company which engaged in the industrial manufacturer of body pail cans. Previously, the process of machine maintenance at company M is to repair the machine when a problem occurs. This causes several machines to break down frequently and disrupt the production process. Furthermore, the purpose of this research is to determine the optimum and well-planned maintenance scheduling that can reduce the risk of-or prevent machine failures that may ruin the production process by doing the preventive maintenance in right time. Ant Colony Optimization (ACO) method was used in this research as maximizing the interval time between preventive maintenance periods before the trouble occurs based on previous breakdown data period as minimizing frequency of the task. In the principle of ACO, the required parameters are α, β, m, e, el. As a result of using ACO with the combination of parameters above, the optimal well-planned maintenance scheduling was obtained by using α=2, β=5, e=0.3, e1=0.96, and a number of ants needed. Finally, the optimizing of schedule maintenance has proposed in daily for next year period.