The need for quick analysis for road pavement survey is inevitable, especially in a developing country. A new data collection method by using small format photo, which is recorded by drone is developed. The function o...
The need for quick analysis for road pavement survey is inevitable, especially in a developing country. A new data collection method by using small format photo, which is recorded by drone is developed. The function of drone is not only for photographic purposes, but also developed to measure and record road damage. Digital aerial photogrammetric methods are developed faster than before. A small format areal imagery based on pixel size is developed for this study, so that the degree of road damage can be obtained quickly. In order to obtain a maximum pixel size to detect a maximum damage level of 1 cm, the shooting is done at a height of 24 m drone from the road surface. The result of road damage measured by measuring distance through image is then tested based on the measured sample, directly in the field with a trust level of 97.83%. These results show that the accuracy of road damage measurements made above high resolution photo images is very effective for data collection of road damage. Analysis of Condition Priority can be obtained in one day in complement with contour map and road level, while in previous time it is done within a week without contour map and level.
Feasibility of developing a geothermal project depends on the financial return generated from the investment. One of the strategies to achieve optimum return is formulating a financial model with a high level of confi...
Feasibility of developing a geothermal project depends on the financial return generated from the investment. One of the strategies to achieve optimum return is formulating a financial model with a high level of confidence. Technical input parameters in the financial model are determined by the amount of available geothermal reserve in the form of a field development scenario. The best method for predicting geothermal reserve is a numerical simulation. The objective of this study is to determine the electricity tariff to generate 30 MW, 60 MW, and 110 MW which meet the 50% of the Rate of Return value will be equal or not exceed 16% (P50) for a specific geothermal field with a probabilistic approach. This study started with determining the technical input parameters: the number of production wells; makeup wells; and injection wells from each development scenarios based on numerical simulation result that has been studied by another researcher. The electricity tariff that meets the P50 of Rate of Return at 16% was calculated for those scenarios. Then, the tariffs were evaluated based on the Average Cost of Electricity Generation (BPP) on the relevant local grid. The result shows that the tariff or/and generation cost need to be negotiated. Moreover, total investment and economic indicators forecasting indicated that the investment was attractive. Lastly, sensitivity analysis shows that Rate of Return strongly affected by well drilling cost and power plant cost (EPCC).
Design teaching which is part of the system development life cycle, both information systems and application systems is very important to be taught, learned and understood in the informatics engineeringstudyprogram....
Design teaching which is part of the system development life cycle, both information systems and application systems is very important to be taught, learned and understood in the informatics engineeringstudyprogram. System design teaching in private universities in Indonesia whose students are very diverse in terms of abilities and skills require teaching materials, lecture strategies, quality of lecturers and facilities that must also be able to adapt to the challenges and complexity in teaching. The study of system design teaching uses Hevner’s information systems research framework which includes the steps of constructing artifacts in the form of constructs, models, methods, instances and evaluation of artifacts using case study in informatics engineering lecture. The use of the framework is intended to support business strategies and processes in studyprograms and to ensure the relevance of research. The result of research is a model and evaluation of the model. First, this research will produce a system design teaching model that can be used as a reference in the informatics engineeringstudyprogram to produce graduates with good literacy, skills using the stages of system design, understanding user needs and system design capabilities. Second, evaluating the model that has been built by applying it to the case study on human computer interaction lecture and measuring the results of lectures to improve the quality of lecture material, teaching and students.
This study aimed at investigating the maintenance management of welding engineering workshops and factors affecting the damage of welding equipment in vocational high schools located in Special Region of Yogyakarta. T...
This study aimed at investigating the maintenance management of welding engineering workshops and factors affecting the damage of welding equipment in vocational high schools located in Special Region of Yogyakarta. The study employed quantitative descriptivedesign. It was conducted at vocational high schools SMKN 1 Sedayu, SMKN 2 Pengasih, SMK Muhammadiyah 2 Wates, and SMKN 1 Pundong. The respondents were heads of workshops, teachers of welding engineering subject, workshop technicians, and students. The data were collected through survey, observation, and interview. The quantitative descriptive technique was employed to analyze the collected data. The results of the study show that the maintenance management of welding engineering workshops in some VHS in Yogyakarta is Very Gooddespitesome problemsin the maintenance procedure. The factors causing the equipment damage are the unscheduled maintenance procedure, absence of inventory lists, lack of technicians, improper use of workshop equipment, and the limited amount of maintenance budget.
The Sawahtambang Sandstone Formation of Sawahlunto, Indonesia has hitherto never been studied in detail to ascertain its depositional processes and its palaeoenvironment. The Sawahtambang Sandstone has more than 394 m...
The Sawahtambang Sandstone Formation of Sawahlunto, Indonesia has hitherto never been studied in detail to ascertain its depositional processes and its palaeoenvironment. The Sawahtambang Sandstone has more than 394 m thickness which consists of conglomeratic sandstone, sandstone, and clay-silt intercalation within which six lithofacies types (St, Sp, Sh, Ss, Fl, and Fm) appear creating iterated fining upward sequence. Herewith, this paper aims to replenish the avantgarde sedimentological interpretation of the Sawahtambang Sandstone in the intermontane basin of Indonesia based on outcrops along the Trans-Sumatra Highway. The study is attained through facies identification based on stratigraphic measuring section or outcrop profile, studio analysis consists of log analysis and superposition reconstruction, and architectural element delineation according to facies association. Structures in clay-silt facies consist of lamination and fissile whereas in the sand grained include planar and trough cross-bedding, planar lamination and granule lag, which depicts a lower-flow-regime sand channel. The architectural elements that made from facies association are identified into five distinct elements (multi-storey channel, single storey channels, sand bedforms, laminated sand sheet, and floodplain fines), which present a fluvial environment. The relation of the architectural elements demonstrates that the Sawahtambang Sandstone uphold a record of the braided river system that flowed from southwest to northeast in the southwestern part of Ombilin Basin. The dominance of coarse-grained (channel and sandy bedform) element over clay-silt grained (laminated sand sheet and floodplain fines) element and the extensive appearance of thick amalgamated channel elements reinforce the interpretation of a low-sinuous braided fluvial system in which the stacking pattern shows the channel bodies accumulated both lateral via lateral accretion of point bar and via vertical amalgamated streams.
The study aims to describe (1) the development stages of the manual arc welding job sheet and (2) its validity. It is a Research and Development (R & D) of which the data were collected by means of non-test instru...
The study aims to describe (1) the development stages of the manual arc welding job sheet and (2) its validity. It is a Research and Development (R & D) of which the data were collected by means of non-test instruments, namely the closed-ended questionnaires with the 5-scale responses. The data were collected from the three research participants acting as the material and media experts,namely two lecturers in the Mechanical engineering Education studyprogram, faculty of engineering (FE), Yogyakarta State University (YSU), and a teacher of the Basic Welding Technique subject. The job sheet development stages were adapted from Thiagarajan’s model, namely the Four-D model covering the definition, design, development, and dissemination. Data were analyzed quantitatively by means of the descriptive statistics. The results of the material evaluation by the material expert I prove that the job sheet is categorized as Appropriate (with the total score of 145 or 82.9%) and Very Appropriate based on the material expert II with the total score of 153 (87.4%). Besides, in terms of the media, the job sheet is Appropriate based on the media expert I (with the total score of 207 or 82.8%) and Very Appropriate based on the media expert II (with the total score of 215 or 84.4%).
The main of tapioca industrial wastes are cassava fiber, cassava skin, and wastewater. To increase the revenue of tapioca industry, cassava fiber was also extracted to produce energy and the effluent of biogas plant w...
The main of tapioca industrial wastes are cassava fiber, cassava skin, and wastewater. To increase the revenue of tapioca industry, cassava fiber was also extracted to produce energy and the effluent of biogas plant was utilized as organic fertilizer. The aims of this research were to estimate energy generation from tapioca wastewater and cassava fiber and also to estimate Nitrogen and Phosphorous potential from the effluent of biogas plant. This research was conducted in a tapioca factory which was equipped with biogas plant, in Lampung Province, Indonesia. Concentration of COD (Chemicals Oxygen Demand), Total Nitrogen (TN) and total Phosphorous (TP) were measured in the inlet and outlet of biogas plant. Enhancement of biogas production from cassava fiber was also estimated. Flow rate of wastewater and cassava fiber production were also measured. Wastewater generation is 2.75 m3/ton of cassava with COD 9,647.5 mg/l. Electricity production was estimated about 29.96 kWh and 30.44 kWh per ton of cassava from the wastewater and cassava fiber, respectively. The observed tapioca factory could be fulfilling energy needs for drying tapioca process if they utilized wastewater and cassava fiber. The effluent of biogas plant also still has potential to produce about 1.15 and 0.05 kg of TN and TP per ton of cassava, respectively.
Occupational Safety and Health (OSH) is a part of the practical courses in educational institutions. This research was aimed at investigating: (1) students' knowledge of OSH used in practical courses, (2) students...
Occupational Safety and Health (OSH) is a part of the practical courses in educational institutions. This research was aimed at investigating: (1) students' knowledge of OSH used in practical courses, (2) students' attitudes toward OSH, and (3) the implementation of OSH in practical courses in the Electronics engineering Education studyprogram, faculty of engineering, Yogyakarta State University. It is a non-experimental study employing a quantitative descriptive approach. This study was conducted in the Electronics engineering Education studyprogram, faculty of engineering, Yogyakarta State University from February to June 2018. The subject of this study included students, lecturers, and technicians. Students' knowledge of OSH in practical courses in the Electronics studyprogram is good (74.2%). Their attitudes toward OSH are also good (92.2%). Although some students do not implement OSH procedures when conducting practical courses, the implementation of OSH in the studyprogram is categorized good (63.3%). Furthermore, more intensive studies on the importance OSH implementation in practical courses needs to done.
Scanning Electron Microscope (SEM) is an instrument that used to observe the surface of an object at a scale of nanometer. However, image degradations caused by blur and noise may be occurred on SEM observation images...
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Scanning Electron Microscope (SEM) is an instrument that used to observe the surface of an object at a scale of nanometer. However, image degradations caused by blur and noise may be occurred on SEM observation images. Its problems limit the process of observing and quantification problem for subsequent image analysis and visualization. To mitigate problems on blur, an estimation of point spread function (PSF) for specific SEM experiment become challenging, due to noise on a measured image. In the work, an edge preserving filter based on spatial and frequency domains are used for support PSF estimation. The performance of proposed scheme is evaluated for SEM images that acquired using Hitachi SU3500. An object TEM grid is imaged using SEM parameters, i.e. accelerating voltage 30 kV, spot size 10, 20, 30, and 40 with magnification 350 times. The results shown that proposes scheme can be confirmation that estimation PSF has characteristic increasing a radius in x-y plane as proportional with increasing spot size of electron beam.
Bangka Island is an important tin producer in Indonesia, mostly from the secondary tin deposits. However, the secondary tin deposit is depleting, causing further exploration shifted to the primary tin mineral. The pur...
Bangka Island is an important tin producer in Indonesia, mostly from the secondary tin deposits. However, the secondary tin deposit is depleting, causing further exploration shifted to the primary tin mineral. The purpose of this study is to make a mineralization model of primary tin deposit in Bangka Island. Methods that implemented in this study are petrographic analysis, mineragraphic analysis, XRD (X-Ray Diffraction), and XRF (X-Ray Fluorescence) analysis. The studied rock samples that consisted of granite, meta-sandstone, and sandstone. Some of the rocks are altered rocks with varying intensity. Petrographic and mineragraphic analysis show the presence of minerals that indicate the primary tin deposits, such as cassiterite, tourmaline, topaz, sericite, pyrite, and sphalerite. XRF analysis shows data about the value of Sn elements so that they can be classified into two classes, very high grade (> 800 ppm), and low grade (100–200 ppm). XRD analysis is necessary to do to determine the type and intensity of alterations that occur in the study area. The results of each analysis will provide supporting information regarding the primary tin mineralization process in Bangka Island.
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