Disain dan Uji Kinerja Pendingin Evaporatif Tipe Aliran Searah Menggunakan CFD (Computational Fluid Dynamics)

After harvesting, fruits will change due to physiological, physical, chemical, and microbiological influences, and they are living materials. Therefore, it is necessary to know how to harvest and handle fresh fruits and their storage conditions to handle the fruits after harvesting so that the quality of the products can be maintained. One of the first treatments in the fruit cold chain is evaporative cooling. In order to get an evaporative cooling system that has an even temperature distribution, it is necessary to make a spatial model when designing an evaporative cooling system using CFD (Computational Fluid Dynamics). The objectives of this research are: (1) design of direct flow type evaporative cooling systems and (2) test the performance of direct flow type evaporative coolers. This research method uses design methods, experiments, and computer simulations. The results showed the performance of the evaporative cooler system in the scenario with the roof on, the highest effectiveness value was 1.198, the highest approximation value was 2.832, and the highest range value was 4.589. In the scenario without a roof on the evaporative cooler system, the highest effectiveness value was 1.767, the highest approach value was 2.139, and the highest range value was 4.835. The CFD analysis in the scenario with a roof had the highest temperature value of 25.9 ° C and the lowest temperature of 21.9 ° C, while the CFD analysis in the scenario without roof had the highest temperature of 23.7 ° C and the lowest temperature of 20.4 ° C. Keywords: CFD, direct flow type, evaporative cooler, quality, fruit

Implementasi Monitoring Suhu dan Kelembaban pada Budidaya Jamur Tiram dengan IOT

Oyster mushroom commodity has been widely used as raw material for processed food products, monitoring of temperature and humidity intensively, the quality will be well maintained. Monitoring at Rumah Jamur Barokah full 24 hours, so it will be difficult if done manually. This is the reason why it is necessary to design monitoring tools in maintaining the ideal temperature and humidity with the concept of the Internet of Things. This research aims to design temperature and humidity monitoring tools (IoT), and how much the increase value of time efficiency and effectiveness after the tool is implemented. The blackbox testing method is performed for performance feasibility testing, by comparing thermo-hygrometers and sensors. The result of the tool performance test at the temperature parameter obtained an error value 0.33 0C and the DHT22 tolerance limit ± 0.5 0C. In the humidity parameter obtained an error of 1.8% RH and the DHT22 tolerance limit ± 2% RH, so the DHT22 sensor feasible to use. In the analysis of efficiency calculation obtained a result of 77.95% for improved time efficiency. In the analysis of the quality effectiveness value of oyster mushrooms is less than ideal, getting an increase in value by 143% to 163%. Keywords: blackbox testing, cultivation, internet of things (iot), monitoring, oyster mushroom

Pengaruh Kadar Perekat Terhadap Karakteristik Briket Arang Limbah Kayu Karet (Hevea brasiliensis Muell. Arg)

The study aimed to determine the effects of adhesive content on rubber wood charcoal briquette characteristics. Wood charcoal was produced using a double-drum retort kiln at > 500°C. Wood charcoals were crushed into powder and then mixed with tapioca adhesive of 5%, 10%, and 15%. The charcoal-adhesive mix was then pressed using a hydraulic press machine. For comparison, rubber wood biomass briquettes were also produced using wood particle-adhesive mix with similar adhesive content. Biomass and charcoal briquettes characteristics as physical properties (density and water absorption), chemical properties (ultimate analysis, and FTIR analysis) and energy properties (calorific value) were evaluated. The results showed that density ranged between 0.52-0.56 g/cm3, water absorption of 6.54-7.47%, C content of 82.67-84.41%, H content of 3.28-3.60%, N content of 0.67%-0.74%, and calorific value of 30.76-32.86 MJ/kg. The results of FTIR analysis showed changes in the spectrum of the wave band on the functional groups OH, CH, C≡H, C=C, and C=O, indicating the decomposition of the chemical components of rubber wood due to pyrolysis. The results prove that increasing the adhesive content can reduce the quality of briquettes. Based on physical, chemical, and energy properties, charcoal briquettes with 5% adhesive showed better characteristics than briquettes with 10% and 15% adhesive content, showing water absorption of 6.54%, C content of 84.41%, H content of 3.28%, and heating value of 32.86 MJ/kg. Keywords: adhesive content, charcoal briquette, pyrolysis, rubber wood waste, tapioca starch

Daya Dukung Sumberdaya Air dan Indeks Kekritisan Air Sub DAS Cisokan Hulu

Upper Cisokan sub-watershed is a natural ecosystem of water resource providers that can be used directly or indirectly by the community in it. The population rate and sectoral needs in a sub-watershed area are estimated have put pressure to the water resources balance. The value of the carrying capacity and the water criticality index in the existing condition and its projections for the next 10 years are known from the water balance analysis. The availability of water resources (Wn) was determined based on the flow rate probability (Q80) of Weibull Method, the value of groundwater estimation, springs and wells, and also the raw water supply of local water company. Water demand (qpt) was estimated based on Statistic data of Upper Cisokan sub-Watershed 2020 and the projection for 2030, industrial data, agricultural area data, livestock production data, and fishery area data. The water resources carrying capacity (Cw) of the Upper Cisokan sub-watershed is generally still adequate (High), but at the peak of the dry season, namely June to November, the water carrying capacity status shows a value of 1.84 (Critical) to 0.24 (Deficit). In general, the water criticality index is still safe (Not Critical), but in the dry period, especially in July, August and November, it shows a value of 125% to 421% (Very Critical). To anticipate the water crisis, all stakeholders should allocate water efficiently according to its availability. So that the sub-watershed ecosystem is sustainably provide ecosystem services for providing water resources to the community. Key words: Ecosystem Services, Water Supply, Water Demand, Water Balance, Water Resources Carrying Capacity, Water Criticality Index, Upper Cisokan Sub Watershed

Pendugaan Umur Simpan Bubuk Kopi Arabika Menggunakan Metode Arrhenius dengan Kemasan Aluminium Foil dan Plastik (Polipropilen)

The storage method is one way to maintain coffee quality. Storage with aluminum foil and plastic (PP) packaging is an effective and safe technology to protect coffee grounds. Specialty coffee powder cannot be accepted if the organoleptic score is below 80, for that it is necessary to estimate the shelf life. This study aims to analyze the quality degradation of Bondowoso arabica coffee powder based on specialty standards using the SCAA protocol during storage with aluminum foil packaging and compare it with plastic packaging (PP) and estimated the shelf life of Bondowoso arabica ground coffee products based on flavor value parameters using the arrhenius method. Coffee powder quality degradation with plastic packaging (PP) is faster than aluminum foil packaging. This is because plastic packaging on the fourth day with a temperature of 40°C is not meet specialty standards. The greater the temperature used, the greater the decrease in quality. The shelf life of coffee powder uses aluminum foil packaging, which is 3 days at 40°C, 2 days at 50°C, and 1.3 days at 60°C. Whereas with plastic packaging (PP), the shelf life is shorter, which is 2 days at 40°C, 1.2 days at 50°C and 1 day at 60°C. Keyword: accelerated Shelf-Life Testing (ASLT), aluminum foil, arabica coffee, packaging, shelf

Respon Pupuk Fosfat dan Silika Terhadap Pertumbuhan Padi Hitam (Oryza sativa L. Indica)

Black rice produces black rice which contains a lot of nutrients for the body, but there is still not much research done in increasing the growth and productivity of black rice. The purpose of this study was to determine the level of increase in the productivity of black rice after the addition of phosphorus and silica fertilizers to black rice varieties. The experimental location is in Palir Village, Tengah Tani District, Cirebon Regency with a height of four 9 m above sea level. The type of soil in the experimental location was alluvial with a pH of 6. The experiment was carried out in March-August 2019. This experiment used a factorial RAK consisting of SP36 (P) fertilizer dosage and SipadiHS (S) Silica fertilizer dosage. The dosage of SP36 (P) fertilizer consists of P1 (50 kg ha-1) P2 (100 kg ha-1) and P3 (150 kg ha-1) while the dosage of SipadiHS (S) silica fertilizer consists of S0 (without silica), S1 (100 kg ha-1), S2 (200 kg ha-1) and S3 (200 kg ha-1). The results showed that there was an interaction with the variable height growth of plants aged 56 DAS in P2S3 and P3S3 treatments and the number of tillers 56 DAS in P2S1 treatment. Meanwhile, phosphate and silica treatments independently affected the observations of plant height at the age of 28 DAS and 42 DAS, Shoot Root Ratio at 42 DAS and 56 DAS. Keywords: black rice, SP36, Silica SipadiHS

Rancang Bangun Hidroponik Dengan Bantuan Pompa Bertenaga Surya

Agriculture traditionally still uses large areas of land with relatively large amounts of water. The application of solar energy is one of the uses of new and renewable energy. This research uses a 50 Wp photovoltaic cell, battery, solar charge controller, DC stepdown, DC pump and hydroponic frame. The stages of the research are the design of the tools, the calculation of the power required by the tools, the manufacture of the tools, the collection of data and the analysis of the data. The data collected is temperature, sunlight intensity, electric power, electrical energy, water discharge, and photovoltaic efficiency. The data were processed and analyzed in an exploratory manner. Based on the results of the research conducted, the lowest average temperature was 25.33 C and the highest was 33.70 C with the highest average light intensity of 920.26 w/m2 at 12.00 WIB. The relationship between temperature and light intensity with a value of R2 of 0.7594. The highest average electrical energy obtained by polycrystalline is 30.44Wh. The water lost from the hydroponic system is 0.03%. The efficiency of photovoltaic cells is 10.09%–15.72%. Keywords: DC pump, hydroponics, light intensity, photovoltaic

Modifikasi Proses Pengolahan Kopi Arabika Menggunakan Metode Honey Process

The amount of mucilage can be adjusted according to the washing intensity. The level of ripeness of the coffee fruit is also directly proportional to the mucilage constituent components. Optimally ripe coffee cherries have a higher sugar, protein, lipid and water content than raw coffee cherries. So that research is needed to determine the effect of washing intensity and level of ripeness of coffee cherries on the characteristics of the resulting taste of coffee. The research design used was a complete two-factor block design. The first factor is the intensity of washing mucilage that sticks to the surface of the coffee beans; 2 times washing, 1 time washing, without washing. The second factor is the level of ripeness of the coffee cherries; raw coffee cherries, optimally ripe coffee cherries, past ripe coffee cherries. The analyzes were carried out, namely water content, ash content, total sugar content, pH value, Brix, and organoleptic test using the SCAA cupping method. The results of this study indicate that washing intensity affects the Brix value, water content, total sugar content, and pH. Whereas in the second factor, the level of ripeness of the coffee fruit affects the Brik value, water content, total sugar content, and pH. This study also showed that there was a correlation between washing intensity and the level of ripeness of the coffee cherries and the preference of the panelists. The non-washing treatment (black honey) and the optimal level of ripeness were the most preferred by the panelists, all coffees produced from this study met SNI 01-3542-2004. Keywords: arabica characteristics, honey process, maturity level, washing intensity

Evaluasi Termal Vertical Greenery System Tipe Green Facade pada Dinding Bangunan

Increasing of ambient temperature due to global warming has a direct impact on increasing the room temperature. Heat from surrounding is transferred to building wall and room. By installing the Vertical Greenery System (VGS) on the building wall, it can be an alternative for heat absorber and eco-friendly indicator. The aims of this study are to determine the temperature that can be reduced by VGS type Green Façade (GF) and achieve the energy consumption reduction because of GF installation. GF is installed on the building wall, property of Mining Engineering Department, Sriwijaya University, to measure its temperature, then compare it with the temperature on control wall. The results showed that the GF can reduce the room temperature up to 1,2oC, compared to the control wall and the average is 0,3oC. The decrease in average temperature causes a decrease in energy consumption due to the use of air conditioners by 1.56-1.92%. Keywords: global warming, green facade, thermal evaluation, vertical greenery system

Dampak Perubahan Curah Hujan Terhadap Tingkat Kerentanan Erosi Tanah Di Sub DAS Merawu, Jawa Tengah

This research was held to estimate rainfall and change in soil erosion vulnerability from 2020 to 2050 in Merawu Sub-Watershed, Banjanegara District with RCP 2.6, 4.5 and 8.5. The RCP is an overview of the concentration trends for greenhouse gases, aerosols and land use change created by the climate modeling community. Rainfall prediction was generated from SDSM Software and combined with USLE to predict soil erosion in ArcGIS 10.4. Changes in rainfall intensity are an important factor in changes of soil erosion rates because the kinetic energy of falling rainwater can cause soil erosion.The results showed rainfall in Banjarnegara Station at 2020-2050 with RCP 2.6,4.5 and 8.5 were increasing by +0,26%; +0,60%; +0,52%, while in Kalisapi Station were decreasing by -1,54%; -1,65% dan -2,20%. The change of soil erosion vulnerability prediction showed that soil erosion in Sub-DAS Merawu at 2020-2050 with RCP 2.6,4.5 and 8.5 in very light category were -0,02%;-0,02%;-0,03%, light category were -0,17%;-0,17%;-0,17%, moderate category -0,05%;-0,05%;-0,04%, heavy category -0,26%;-0,35%;-0,37%, and very heavy category were +1,46%;+1,88%;+1,95%. While the average soil erosion prediction at RCP 2.6, 4.5 and 8.5 were +0,86, +1,19% and +1,03%, respectively. Keywords: soil erosion prediction, rainfall prediction, SDSM Software, Sub-DAS Merawu