Politeknosains http://jurnal.politama.ac.id/index.php/jp <p>Jurnal Teknik Politeknik Pratama Mulia</p> Politeknik Pratama Mulia Surakarta en-US Politeknosains 1829-6181 <p><strong><span style="text-decoration: underline;">Authors who publish with this journal agree to the following terms:</span></strong></p> <ul> <li style="text-align: justify;">Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.</li> <li style="text-align: justify;">Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.</li> <li style="text-align: justify;">Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).</li> </ul> TM EFEK VARIASI KANDUNGAN AIR TERHADAP KERJA GAS ENGINE COOLER SUATU PLTB LIMBAH ORGANIK PASAR INDUK http://jurnal.politama.ac.id/index.php/jp/article/view/191 <p>Organic waste from wholesale market can be degraded to biogas by anaerobic digestion. In PLTB, biogas which has main composition of methane is used as fuel for gas engine to generate electricity. Before being used in the gas engine, biogas is purified and condensed to remove impurity gases. Biogas purification process used a high pressure water scrubber while for condensation used a gas engine cooler. The working of cooler is removing saturated water vapour before gas being burned into gas engine. The purpose of this research is analyzing the effect of water content to the working of cooler for removing water vapour in biogas. To analyze the working of cooler, mass flow of water for anaerobic digestion and water for scrubbing process is varied and simulated by the software AspenPlus V 8.6. In this simulation result, water influences to remove the impurity gases including water vapour. When the input of water is greater in feedstream or make up water, cooler removes water vapour is getting smaller because water vapour dissolved in the water is more. Keywords: organic waste, biogas, PLTB, gas engine, cooler, water.</p> Dede Hanafi Fajrin Nazarudin Sianaga ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2018-05-30 2018-05-30 15 1 1 8 TM MATERIAL SEMIKONDUKTOR ZnO DIDOPING Cu UNTUK MENINGKATKAN KONDUKTIVITAS THERMAL http://jurnal.politama.ac.id/index.php/jp/article/view/192 <p>Manufacture of semiconductor material ofzinc oxide (ZnO) doped with copper (Cu) aims to obtain a good p-type semiconductor material ZnO1-xCuxO. Materials zinc nitrate tetra hydrate and copper nitrate trihydratearean initial material which are combined through a process of mixing the powder in solution with varying content Cu of 0%, 2%, 4%, 6% and 8% mol. Next, the solution is dried, calcined and compacted into pellet form. The pellet is sintered with temperature 1300oC. Results of testing showed the characteristics of materials Zn1-xCuxO containing Cu and testing operating temperature at 450oC generates biggest value for the thermal conductivity of 1.85 W / mK. The amount of material doping affect the the thermal conductivity Keywords: p–type semiconductor materials , thermal conductivity, Cu doped ZnO.</p> Bayu Prabandono Agus Kurniawan Bram Armunanto ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2018-05-30 2018-05-30 15 1 9 14 TM PENGARUH PENGGUNAAN BAHAN BAKAR LGV PADA MOBIL PENUMPANG 1200 CC DAN 1500 CC TERHADAP KEBUTUHAN UDARA DAN BAHAN BAKAR http://jurnal.politama.ac.id/index.php/jp/article/view/193 <p>LGV (liquefied gas for vehicle) is one of the alternative fuel, which prioritized for a fuel diversification program of transportation sector in Indonesia. Having different characteristics and properties of gasoline fuel, the use of LGV fuel will have an effect on the working parameters of an engine. Based on that, this research is conducted to analyze the effect of using LGV fuel at a mass air flow rate and fuel rate in passenger cars. Through this research also expected as an act to support the diversification fuel program that proclaimed by Indonesia Government. Passenger cars used in this research have a different engine capacity, i.e., 1200 cc and 1500 cc. Measurement of mass air flow rate and fuel rate are performed with the throttle position variation (absolute throttle position) from 14% to 30% on third gear. The results obtained indicate that there is a decrease in air and fuel flow rate of 4% for the test car Honda Mobilio (1500 cc) and 2% for Mitsubishi Mirage (1200 cc). In addition, the air fuel ratio (AFR) of LGV fuel has the same range like fuel petrol mixing, the value of the measured air fuel ratio is 14.4-14.8 for Honda Mobilio and 13.5-14.6 for Mitsubishi Mirage. The lower value of fuel flow rate than gasoline fuel, prove that the use of the LGV fuel is more efficient and cheaper (due to the LGV price) than gasoline. In addition, LGV fuel also more environmentally friendly than gasoline fuel as seen from result of emission testing done by the most researchers. Keywords: fuels, LGV, passenger cars, throttle position.</p> Amirur Rozak Nazaruddin Sinaga ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2016-03-30 2016-03-30 15 1 15 23 PENGARUH VARIASI DIMENSI SALURAN TUANG TERHADAP FLUIDITAS, POROSITAS DAN KEKERASAN PENGECORAN DENGAN BAHAN BAKU ALUMINIUM BEKAS http://jurnal.politama.ac.id/index.php/jp/article/view/196 <p>Quality casting one of which depends on the system and the sprue size, so need to analyze the effect of sprue size, till how long aluminum molten able to flowing in sand molds.With made variations diameter in gate expected to be obtained capable of a maximum flow or is able to flow most distant. This will assist in completing the castings process for cast objects with a certain length. The purpose of this study was to determine the effect of variations dimensions sprue to fluidity, porosity and hardness foundry of the raw material for aluminum scrap. Smelting process carried out in the laboratory of the foundry Department Mechanical Engineering University of Proklamasi 45 Yogyakarta. The smelting process using the crucible furnace on it be put kowi the place aluminum to be melted down. Sand mold is made of 3 pieces for each sprue 1 (d1), sprue 2 (d2), sprue 3 (d3). Patterns made with thickness 3 mm, 4 mm, 6 mm and 7 mm. The measurement results calculated averages value length fluidity for each thickness the castings. Observations the porosity was do by weighing of the castings (mass, kg) divided by the volume of the castings, so obtainable the density of the castings. Hardness testing is done with the kind of Vickers hardness test. Testing in this study using a 200 g load suppression, loading time 10 seconds, using a hardness machine types Buehler High Quality Micro Hardness Tester 0054 MM models. The testing results and observations indicate that the longest fluidity with diameter sprue 13 mm for thickness objects 3 mm and 4 mm with length is 251.7 mm and 290 mm. The fluidity longest also be obtained on castings the sprue diameter 15 mm with thick 6 mm and 7 mm is 296.86 mm and 343.33 mm. Hardness testing results show the value of the highest hardness on sprue diameter 17 mm is 107.98 VHN, while the value of the lowest hardness on sprue diameter of 15 mm is 88.3 VHN. Porosity observations showed that diameter sprue 17 mm obtained the lowest porosity level that is equal to 2.734 gr/cm3, while the level of the highest porosity is obtained on the diameter sprue13 mm castings of 2.831 gr/cm3. Keywords: sprue, casting, aluminum scrap</p> Sumpena Sumpena ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2016-03-30 2016-03-30 15 1 24 31 TM KINERJA ROOM AIR CONDITIONER (RAC) WINDOW BERDASARKAN VARIASI TEKANAN PENGISIAN http://jurnal.politama.ac.id/index.php/jp/article/view/197 <p>This research was started with making the practice of media of Window Air Conditioner which will be used to teach Practice Refrigeration and Air conditioner subjects. The objective of this media was to explain the name, function, layout of the electrical and main components, R-22 circulation, evacuating the system, charging, and the working principle of the electrical system. The Media of window air conditioner was made in the Laboratory of Bench Work and Electrical Power Engineering in Politama Surakarta, which consists of the electrical and main components, and wiring diagram. The data were collected by observation, interview, and documentation. The research began by testing the system, namely: evacuating the system, then R-22 charging. The pressure of R-22 charging was varied from 23%, 38%, 45%, 55%, and 60% of the high pressure standard. The standard pressure on the window air conditioner was 4.8 bar or 70 psig with evaporation temperature 50C ( the low pressure side), and 16.3 bar or 236 psig at a temperature of 450C condensation (the high pressure side). The standard electric current in this research was 3,6A for compressor motor and 0,1A for fan motor. Data were analyzed by comparing the results of research observation with its default value, hereafter are described in percentages. Based on the research results, the system can achieve the vacuum pressure -30 in Hg within 3 minutes, and didnot experience leakage within 24 hours. The electric current on the compressor motor is proportional with increaseing charging pressure (42% - 61% of the standard current). The electric current of the fan motor in accordance with nameplate or standards, 0,1A (0%). The biggest percentage of input temperature is the evaporator (420% - 480%), then the compressor (164% - 173%), thereafter the condenser (51% - 61%) and the smallest is the capillary tube (29% - 38%). The biggest percentage of output temperature is the capillary tube (420% - 480%), then the evaporator (164% - 173%), thereafter the compressor (51% - 61%) and the smallest is the condensor (27% - 32%).The working principle of the media of window air conditioner consists of five positions, namely: Off, Fan, Super Quiet, Normal, and High Power. Keywords: the media of window air conditioner, pressure and standard current, evacuating and charging, working principle.</p> Jumardi Jumardi ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2016-03-30 2016-03-30 15 1 32 42 PERBANDINGAN KINERJA DATABASE SERVER MYSQL DAN SQL SERVER ( STUDI KASUS DATABASE SERVER POLITAMA SURAKARTA) http://jurnal.politama.ac.id/index.php/jp/article/view/198 <p>There are various kinds of database server application, including MySQL and SQL Server. Each <br>has advantages and disadvantages. Politama server uses SQL Server as its database server <br>application. Program used to access this server is created with desktop applications. Up to this time <br>applications can run smoothly. However, if the server is used to serve as many data requests at the <br>same time, servers are often slow to respond. One solution to overcome this problem is to use an <br>alternative database server application such as MySQL. Before it is implemented, we try to examine <br>the response speed between SQL Server and MySQL.<br>Comparisons were made using two computers with identical specifications. SQL Server and <br>MySQL installed on each computer. Then, an application is created to access both the database <br>server application. The tested instructions are SELECT, INSERT and DELETE.<br>The results showed that MySQL applications provide better performance on all SQL commands. <br>Access time to MySQL 1.85 times faster in SELECT command and 18.25 times faster at INSERT <br>command KRS table records. The difference of access time increase as the number of record <br>increase.<br>Keywords: <em>database, MySQL, SQL Server, comparison</em></p> Agus Haryawan ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2018-05-30 2018-05-30 15 1 43 49 DIGITAL IMAGE WATERMARKING (DIW) MENGGUNAKAN WAVELET TRANSFORM DOMAIN http://jurnal.politama.ac.id/index.php/jp/article/view/199 <p>Digital Image has its advantages can be duplicated easily. Need to add information embedded <br>on digital image as a mark of Multimedia Intellectual Property Rights. Technology to embedded <br>mark into images called Digital Image Watermarking (DIW). <br>This research aimed to : created software Digital Image Watermarking (DIW) in Wavelet <br>Transform Domain, that can be applied by the public. <br>The methods for this research are :1. Study Literature, 2. Sampling method, distributed some <br>questionnaire to public, and then from the result, we can take the sample for preliminary data, so <br>the conclusion about Digital Image Watermarking (DIW) can be obtained, 3. create the Digital <br>Image Watermarking (DIW) software. DIW given an attack geometric transformation: scaling, <br>cropping, translation, rotation, compression, and median filter.<br>The result of this research is Digital Image Watermarking (DIW) in the wavelet transform <br>domain, with spread spectrum mark robust to geometric transformation: scaling, cropping, <br>translation, rotation, compression, and median filter. The conclusion is Digital Image <br>Watermarking (DIW) in the Wavelet Transform Domain as the technology of Multimedia <br>Intellectual Property Rights robust to geometric transformation.</p> <p>Keywords: <em>digital image watermarking, wavelet transform domain, multimedia intellectual </em><br><em>property right, geometric transformation.</em></p> Yoiceta Vanda Setyawan Ary Cahyono ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2018-05-30 2018-05-30 15 1 50 57 POSI TI ONING DENGAN TEKNOLOGI BLUETOOTH MENGUNAKAN NAÏVE BAYES ALGORITMA http://jurnal.politama.ac.id/index.php/jp/article/view/200 <p>Bluetooth has emerged as a viable choice of technology in indoor positioning systems due to the <br>increase in the number of Bluetooth-enabled devices over the last decade. Bluetooth was initially <br>developed as a cable replacement technology but properties such as low cost and high availability <br>has led to the development of several indoor positioning systems relying on Bluetooth signals.<br>The characteristics of the Bluetooth device’s RSSI (Received Signal Strength Indication) <br>value were analyzed in preliminary experiments. According to the results of these experiments, <br>the proposed method combines processing using RSSI value threshold and handling of <br>instantaneous variation of RSSI value. Fingerprint data retrieval is done with each grid size 1m <br>x 1m and 2m x 2m. RSSI measurements performed at room Politeknik Pratama Mulia Surakarta. <br>Determination of the estimated location of the object is determined using Naïve Bayes algorithm<br>From the research known influence on the measurements include a fingerprint grid sizes, <br>algorithms and extensive amount of data from the fingerprint data measurement locations. The best <br>results of testing of algorithms to generate distance 1m greatest accuracy. From the results with 1 <br>meter got the result of 1.6 meters and 2 meters with 2:04 to scenario 2 results will be the first got <br>the result 1.85m m2 and 2 m2 with the results of 2.06 The test results of unknown size on the grid <br>one meter better than 2-meter grid.</p> <p><br>Keywords : <em>positioning, bl uetooth, naive-ba yes algoritma</em></p> Yusuf Eko Rohmadi Taman Ginting Didik Warasto ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2018-05-30 2018-05-30 15 1 58 65 MEDIA PEMBELAJARAN INTERAKTIF UNTUK PELAJARAN GEOGRAFI KELAS IX SMP DENGAN MACROMEDIA FLASH PRO 8 http://jurnal.politama.ac.id/index.php/jp/article/view/201 <p>One of the ways to deliver learning materials to students is through Instructional Media. By the <br>using of the media, students may accept and understand the topic effortlessly. With the rapid <br>development of technology and science, an interesting and easily understandable application is <br>needed by the students to study the social sciences-especially, for the ninth grade Geography <br>lessons- that aim to support the absorption process of learning materials.<br>The base of this application construction is the using of action script programming language, <br>combined with the animation created using Macromedia Flash Pro 8 applications are supported by <br>Adobe Audition CS5.5.The data material taken from textbooks geography class IX in accordance <br>with the applicable curriculum. This application contains the main and sub materials of teaching <br>materials, evaluation questions along with assessment results of the evaluation, and reference <br>sources of of teaching materials. To improve the attractiveness and for ease of understanding, <br>teaching materials presented in the form of text, video and audio are packed into animations. GUI <br>designed suitable to the characteristics of students of class IX.<br>From the examination result, it can be concluded that the use of interactive learning media is <br>capable to facilitate educators (teachers) to provide more effective and attractive learning delivery <br>alternatives. It is expected to arouse the interest of students to learn Geography.</p> <p><br>Keywords: <em>learning media, macromedia, interactive learning, geography</em></p> Harjono Harjono ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2018-05-30 2018-05-30 15 1 66 72 PENGOLAHAN DATA PENGIRIMAN PAKET DI PT POS INDONESIA SURAKARTA MENGGUNAKAN BAHASA PEMROGRAMAN VISUAL BASIC 6.0 http://jurnal.politama.ac.id/index.php/jp/article/view/203 <p>Data-Processing of Package Delivery In PT. Post of Indonesia Surakarta use the programming <br>language visual basic 6.0. with the progress of information technology in this time computer play a <br>part very important in the world of job. In technological growth this computer can assist the us in <br>producing and to save information in a complex system information.<br>In general computer used for the hollowing of duty like typing, but in fact knowledge about <br>computer need more developing so that can overcome the problems which complex progressively.<br>As for one of example of problems able to be overcome with the computer peripheral that is <br>problems of delivery of goods package that happened in PT. Post of Indonesia Surakarta By using <br>programming language of visual basic 06, in this paper writer hope can assist the PT. Post of <br>Indonesia Surakarta in solving problems of delivery of goods package especially, so that will get <br>the data and report which quickly, precisely and accurate. By using input of scrip certificate <br>transaction, town data, data of tariff of package and transaction claim so that can complete the <br>process which have there.<br>Keywords : data-processing, Visual Basic, system information</p> Didik Warasto ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2018-05-30 2018-05-30 15 1 73 82 SISTEM INFORMASI AKADEMIK PROGRAM STUDI SISTEM KOMPUTER BERBASIS VISUAL BASIC 6.0 http://jurnal.politama.ac.id/index.php/jp/article/view/204 <p>Academic Information System is built to address directly the problem and the need for<br>universities to academic management quickly and accurately. Academic Information Systems at the<br>University of Computer Studies Program Surakarta is still manual, including student database,<br>collection, processing subjects and values. Under these conditions required the existence of an<br>information system design technology to minimize constraints on information systems manual.<br>Academic Information System is built using the programming language Visual Basic 6.0, while<br>the database using Microsoft Office Access 2007. Chronology of Academic Information Systems<br>program design begins with collecting data, database design, designing queries, designing an<br>application in Visual Basic 6.0, compile the source code in visual basic 6.0, the output design<br>applications with crystall report and compile the source code in crystall report.<br>Academic Information System Study Program Computer Systems built containing information<br>about KRS and student database. Academic Information System is implemented in the Program of<br>Computer System Studies University Surakarta. The output of Academic Information Systems built<br>already meet the standards required in the study program.<br>Keywords: academic information system, Visual Basic 6.0, Microsoft Office Access 2007, <br>Department of Computer Systems</p> Cicilia Puji Rahayu Aditya Riawan ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 2018-05-30 2018-05-30 15 1 83 92