cover
Contact Name
Eko Didik Widianto
Contact Email
rumah.jurnal@live.undip.ac.id
Phone
-
Journal Mail Official
jvsarvokasiundip@gmail.com
Editorial Address
Vocational School of Diponegoro University Jl. Prof. H. Soedarto, S.H. Tembalang, Semarang 50275
Location
Kota semarang,
Jawa tengah
INDONESIA
Journal of Vocational Studies on Applied Research
Published by Universitas Diponegoro
ISSN : -     EISSN : 26848090     DOI : -
Core Subject : Engineering,
Journal of Vocational Studies on Applied Research [e-ISSN 2684-8090] is an open access peer reviewed journal published by Vocational School Diponegoro University Semarang Central Java Indonesia. Journal of Vocational Studies on Applied Research is an Journal publishing academic and industrial topics which covers area of interest on applied research as well as vocational studies. Research papers on Engineering, Science and Vocational Studies are welcomed. The Journal is double-blind reviewed which accepts Original Research Paper, Short Communication and Review Articles.
Articles 75 Documents
Design of Blowdown Line LNG Filling Station ISO Tank Ariwibowo, Didik; Wahyuddin, Wahyuddin; Murni, Murni; Sutrisno, Sutrisno; Handayani, Sri Utami
Journal of Vocational Studies on Applied Research Volume 1, Issue 2, Year 2019 (October 2019)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (638.801 KB) | DOI: 10.14710/jvsar.v1i2.4805

Abstract

LNG (Liquid Natural Gas) is a liquefied natural gas, with composition of 87% - 96% methane, 1,8-5,1% ethan, 0,1-5,1% propane and other compounds. The composition of natural gas (LNG formation) varies depending on the source and the process of its formation. Methane gas in LNG has odorless, non-corrosive and non-toxic properties (Air Products, 1999). LNG is basically an alternative method to deliver gas from producer to consumer. When cooled to -162˚C at 1 atm pressure, natural gas becomes liquid and its volume decreases up to 600 times (Handbook of Liquefied Natural Gas, 2014). With such a large volume reduction, liquefied natural gas (LNG) can be transported through the Tanker Ship and the ISO Tank Truck. PT Badak NGL has 3 (Three) T.U.K.S (Terminal For Ownership) As Tanker Ship Facilities and 1 (One) LNG Filling Station as a means of filling LNG to ISO Tank. Development of business process of PT. Badak NGL leads to an increase in LNG filling Station capacity. Along with the plan to increase the filling station capacity, the problem of BOG (Blow of Gas) wastage along with some LNG to ground flare becomes a serious concern. When the number of fillling stations is only 1 (one) station, the BOG wasted condition is not significant. However, with plans to increase the number of filling stations, BOG wasted need to be considered to be fully utilized. Therefore, there is a thought to utilize BOG to become more economic value, through the design of blowdown line on LNG ISO Tank filling station. In the Design of this line Blowdown, Using Pipe Ø2 "(PIPE BE 40S SS A312-TP305 SMLS) interconnecting with Pipe Ø6" (PIPE BE 40S SS A312-TP305 SMLS) BOG Header of new Filling Station under construction (Beginning January 2018 ).
Mechanical Properties of Commercial Recycled Polypropylene from Plastic Waste Handayani, Sri Utami; Fahrudin, Muhamad; Mangestiyono, Wiji; Hadi Muhamad, Alaya Fadlu
Journal of Vocational Studies on Applied Research Volume 3, Issue 1, Year 2021 (April 2021)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (331.225 KB) | DOI: 10.14710/jvsar.v3i1.10868

Abstract

In Indonesia increasing the use of plastic will increase plastic waste because waste management in Indonesia is still poor. Plastics can be recycled and used to make plastic bags, toys and various household utensils, but their use is still very limited. This limitation is because the strength of recycled plastic is not as good as virgin plastic pellets, so the resulting product tends to be brittle. This study aims to determine the mechanical properties of plastics made from recycled polypropylene plastic. Five specimens are made according to the ASTM D 638 type II standard. The results show that yield strength is 16.357±2.65 MPa, elastic modulus 295,926 ± 41,97 MPa and ultimate tensile stress 19,701±1,261 MPa. The yield stress of recycled polypropylene has a lower value than the yield stress on recycled polypropylene studied by Abdelhaleem et.al or Barbosa et.al which is around 21 MPa[7][5]. This difference is possible due to the different quality of raw materials and processing.
Credit Transfer System (CTS) Design in Academic Information System of Diponegoro University Subari, Arkhan; Fauzi, Adnan
Journal of Vocational Studies on Applied Research Volume 1, Issue 1, Year 2019 (April 2019)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (560.755 KB) | DOI: 10.14710/jvsar.v1i1.4293

Abstract

One of the information system built in Diponegoro University is Academic Information System. This system manages every process and outcome of academic activities. Academic information system is developed to meet the needs of process and academic data that is also always growing. One of growing academic process is the implementation of Credit Transfer System (CTS). Credit Transfer System is an academic process whereby every Diponegoro University student can attend lectures in subjects that are interested without being tied to courses and curriculum. The realization is that every student can take a course or KRS interest in any study program in Undip. With the implementation of the CTS, the Academic Information System should be developed by adding new features to adopt the system. The application of CTS in academic information systems is done by adding a group of menus to the academic information system, offering CTS courses, creating a CTS lecture schedule, looking at college schedules, viewing and printing present CTS lectures, creating UTS and UAS schedules, printing UTS and UAS att
Reliability Analysis of Fire Water Line Sutrisno, Sutrisno; Ariwibowo, Didik; Darmanto, Seno; Mangestiyono, Wiji; Saputra, Galih Satria Hendri
Journal of Vocational Studies on Applied Research Volume 2, Issue 2, Year 2020 (October 2020)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1022.22 KB) | DOI: 10.14710/jvsar.v2i2.7773

Abstract

The purpose of this research is to analyze the reliability of firewater as a water distribution for emergency conditions.  To determine the remaining useful life (RUL) of the firewater line, this research will apply the counting process so that the rate of remaining useful life (RUL) of the firewater line can be known. The data used as the basis for calculation is failure data gained from technical division databases from 2018. The data obtained will be processed using visual inspection and ultrasonic thickness test methods to produce the remaining useful life of the firewater line. From 5 example fire water lines, only 3 needed to replace of firewater line cause less than 10 years. RUL to 9 years at 10” and 12” Train C/D, 2.45 year at 14” Train C/D, 8 years at 10” and 12” Utilities I.   The mathematical modeling will be verified using visual thickness and ultrasonic Test method to ensure Remaining useful life of firewater line at Badak LNG. Visual inspection refer to API 571 and ultrasonic test refer to API 570 and ASME B31.3
Temperature Optimization and Addition of Aloe Vera Gel as Antibacteria In Coconut Oil-Based Liquid Soap Rahman, Azizah; Paramita, Vita
Journal of Vocational Studies on Applied Research Volume 3, Issue 2, Year 2021 (October 2021)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (305.56 KB) | DOI: 10.14710/jvsar.v3i2.12655

Abstract

This study aims to determine the optimization of the ratio of coconut oil to KOH and temperature in the manufacture of liquid soap. In this study, the saponification reaction was used by reacting coconut oil with a strong base of KOH. The mole ratio between coconut oil and KOH used is 1:3, 1:4 and 1:5. The temperature used 3 points, there are 30oC, 40oC, and 50oC. Parameters observed were free fatty acid, pH, free alkali content, unsaponication fat content, density, and viscosity. The best results in the physiochemical test were running 4 (KOH ratio 5 and temperature 50oC) with pH 8, free alkali content of 0%, unsaponication fat content of 0.00175%, density 1.02 g/ml, viscosity 715.87 cP, and 1% free fatty acids. The critical value for the optimization of the liquid bath soap formula on the level of unsaponification fat based on RSM data is achieved at a KOH ratio of 4.28758 with a temperature of 62.40793oC.
Cultural Immersion Program as a Potential Live Laboratory for Applied English Students in Indonesia Reswari, Girindra Putri Ardana; Kalimanzila, James
Journal of Vocational Studies on Applied Research Volume 2, Issue 1, Year 2020 (April 2020)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (178.479 KB) | DOI: 10.14710/jvsar.v2i1.7631

Abstract

Applied English students as vocational future graduates must be prepared to be ready to work in international atmosphere directly after they are graduates. One of the most essential skills that should be learned is intercultural interaction. There are two problems that should be answered in this research. First, how is the previous implementation of CIP in Indonesia? Second is why CIP can be used as live laboratory for applied English students? The purpose of this research is to discuss and analyze the success of CIP in Indonesia and its potentials of Cultural Immersion Program (CIP) in becoming the live laboratory for Applied English students. Reflected on the increasing number of International Students in Indonesia, many Cultural Immersion Programs (CIP) held by some institutions to build interaction between local society and international students. This research is a qualitative study. The data is collected by asking 30 international students. This study found that the implementation of CIP in Indonesian is seen as something effective to learn about Indonesia by the international students who ever joined the program. Another finding is CIP could be a miniature of the working place for international tourism since it also has intercultural interaction as well as has same goal and principle with international tourism. Therefore, it could be a potential live laboratory for Applied English students in Vocational School at the university level.
The Effect of Bacillus subtilis on Bioethanol Production from Ambon Banana (Musa paradisiaca var. sapientum Linn) Peels by Using Fermentation Process Bilyartinus, Gaudentius; Siswanto, Anggun Puspitarini
Journal of Vocational Studies on Applied Research Volume 3, Issue 2, Year 2021 (October 2021)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (325.352 KB) | DOI: 10.14710/jvsar.v3i2.11081

Abstract

The breakthrough to optimize Indonesia's energy is by utilizing abundant renewable energy sources. Its geographic location has the potential to become a country with the largest renewable energy source in the world. The potential energy that comes from vegetables is called bioethanol. Bioethanol is an organic fuel produced by bioethanol fermentation. It can be an alternative material for making sanitary products amid the increasing spread ofCOVID-19 in Indonesia.So the authors try to innovate how to use Ambon Banana (Musa paradisiaca var. sapientum Linn) peels to become bioethanol. This research aimed to investigate the effect of Bacillus subtilis in the fermentation of bioethanol production from Ambon banana peels. The methods used were pretreatment, hydrolysis, fermentation, and distillation. Bacillus subtilis and Saccharomyces cerevisiae ratio (10: 5 and 5: 5) use for obtaining high ethanol yields, as well as variations in pH 2 and 6 in the fermentation starter. The variable were designed by using Factorial Design. The result shows the yeast ratio of B. subtilis and S. cerevisiae (10: 5) resulted the highest concentration of bioethanol (6%) in 6 days. In acidic conditions (pH 2), the bacteria don’t grow optimally. The higher concentration of bioethanol (6%) was reached  in pH 6.The research supports the Government Program Reducing the dependency of fossil fuels and innovation to produce sanitary product from bioethanol.
Modification of Drain Hayward Strainer Pipe Header Pipes to Improve Efforts of Cooling Water Pump Train EF Badak LNG Bontang Murni, Murni; Ferdiyanto, Riky; Darmanto, Seno; Ariwibowo, Didik
Journal of Vocational Studies on Applied Research Volume 1, Issue 2, Year 2019 (October 2019)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2426.156 KB) | DOI: 10.14710/jvsar.v1i2.4815

Abstract

In Badak LNG the role of the cooling water pump is very important, and becomes the main support for transferring sea water where the water is used in the cooling process of industrial machinery or as emergency safety for firefighters. Water pump cooling has a hayward strainer that serves to filter water with a smaller filter so that the cooling water that is sent is completely free of dirty water. The purpose of this final project is to find out the main causes of the performance degradation of the EF cooling water pump due to the barrier to the hayward strainer which results in lower pressure on the cooling water. The methodology applied was based on field observations and conducted a solidwork simulation test. Field observations show that when more than one hayward strainer is in backwash, the effectiveness of backwash release decreases because the main disposal of the hayward strainer becomes one. The solidwork simulation found that the pressure on the Hayward train E strainer was high enough to create back pressure and limit the flow of the Hayward strainer outlet. By performing actual simulations by only running only one exhaust system at Hayward train E trainer has improved performance on the hayward strainer system. The performance analysis of the cooling water pump was carried out to determine the cause of the pump pressure drop on the hayward strainer and it was found that the main cause of performance was due to back pressure disposal, the pressure was increasing at each outlet of the Hayward strainer which had more distance to the outlet drain. Taking into account the problem of back pressure, separating the train E and F cooling water pump lines is a good choice. After simulating solid work, the separation of the E train line and the F colling water train shows an increase in the performance of the cooling water pump system because the Hayward strainer runs well so that the pump pressure is maintained for the industrial engine cooling needs.
Effect of Winglets on Improving Wind Turbine Performance Handayani, Sri Utami
Journal of Vocational Studies on Applied Research Volume 3, Issue 1, Year 2021 (April 2021)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (328.987 KB) | DOI: 10.14710/jvsar.v3i1.10906

Abstract

Indonesia, with the longest coastline in the world, has enormous potential to develop large-scale wind energy. In wind turbines, the formation of a wake behind the wind turbine can reduce efficiency. It is estimated that the formation of a vortex tip behind the wind turbine blade can be reduced by adding a winglet. The main function of winglets attached to the blade is to reduce the effect of the wingtip vortices which are generated due to 3D spanwise flow that occurs because of the pressure non- equalization between the upper and lower blade surfaces. This paper aims to summarize the results of research on the effect of adding winglets to wind turbines.
Economic Factor on the In Situ Vanillin Enzymatic Formation from the Green Pods Vanilla Hartati, Indah; Ardi, Pradipta Risma Rukma; Milzam, Muhammad; Paramita, Vita
Journal of Vocational Studies on Applied Research Volume 1, Issue 1, Year 2019 (April 2019)
Publisher : Vocational College of Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jvsar.v1i1.4294

Abstract

This work proposed a study of a direct enzymatic of vanillin formation by using rumen liquid which has enzymatic capability for tissue disruption of vanilla green pods to avoid the curing process. Application of enzymes during the formation of vanilla aromas and its extraction present nice opportunity to improve productivity, as the enzymatic reaction possibly substitute the microbial process in the traditional fermentation. Green vanilla pods were applied for the direct enzymatic extraction of vanillin, while liquid rument provide cell wall degrading enzyme in order to support the hydrolysis process (destruction) of cell wall. Glucovanillin were contacted with the β-glucosidase in the green pods due to the desruction of the cell wall, followed by the formation of glucovanillin into vanillin. Vanillin content of vanilla green pods was found higher in which by treating the vanilla green pods at 30 °C.