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This study aims to analyze the application of human resource management strategies at the Bintan Regency Environmental Office. This research is a study that uses qualitative research. The results showed that the implementation of human resource strategies at the Bintan Regency Environmental Office has been implemented but must be developed again because basically human resources have many differences for each individual. Planning at the Bintan Regency Environmental Office has been done well through planning, implementation, organizing. In terms of organizing, human resources owned by the Bintan Regency Environmental Office are still developing and training in order to implement the policies contained in the Bintan Regency regional regulations because the Bintan Regency Environmental Office is engaged in the government sector that regulates government regulations through policies that have been regulated in law.

The Government of the Republic of Indonesia through Presidential Regulation Number 100 of 2014 and Presidential Regulation Number 117 of 2015 aims the construction of the 2770 km Trans Sumatra Toll Road from Bakauheni to Banda Aceh to be fully constructed by 2024. There are two key stages in the project phase, i.e planning and construction stages. The planning stage is carried out using the Building Information Model (BIM), while the construction phase integrates BIM with 3D-Machine-Control. This study is conducted in Trans Sumatera Pekanbaru - Bangkinangs Toll Road with 40 kilometers long as a study case. The data acquisition methodology is conducted using qualitative and quantitative methods throughout the fields experiments. This study conducted the examination of the LiDAR UAV digital surveys accuracy, the BIM implementation on Level of Development (LOD) 200, 300, and 400, verification of the usage of Motor Grader with 3D-Machine-Control efficiency in elevation cutting works, and the application of Vibro Compactor with 3D-Machine-Control for improving the accuracy of soil compaction on the subgrade and base course. The results showed that the topographic data from UAV LiDAR are accurate within LE90 accuracy with 0.176 cm. The optimalization of 3D-Machine-Control could carry out the earthworks as similar as design also can be used as quality and quantity control. The time efficiency which obtained from implementing Motor Grader with 3D-Machine-Control for elevation cutting application is 47 percent.

Construction industry activities are increasing. Construction industry players need to be prepared to face the possibility of changes of design planed that are not in accordance with field conditions. The purpose of this research is to identify, analyze the causes and impacts of Contract Change Orders (CCO) at the pre-construction, construction implementation, and post-construction stages with case study is Proyek Simpang Susun Balaraja Timur at Tol Jakarta – Merak, Kabupaten Tangerang. The research method used is descriptive and qualitative methods by conducting Earned Value Analysis and Fishbone Analysis to identify the causal factors and impacts of CCO so that efforts can be made to mitigate the performance of the construction contract from the aspect of quality, cost, and time. The results of the analysis show 3 factors causing CCO namely consultant factors, such as lack of planning preparation and non-compliance with field conditions, project owner factors, and contractor factors. The results of Earned Value Analysis with Estimate at Completion (EAC) calculations can be used to identify the need for additional contract value and additional execution time. On initial contract identification: Cost Performance Index (CPI) is 0.77 (insufficient costs with cost overrun – Rp. 52.502,111,631.83) and Schedule Performance Index (SPI) 1.21, means that Addendum 1 needs to be done with the results: CPI is 1.17 (the costs used are sufficient from the available fees), EAC is Rp. 189,848,751,106.02 with changes in the contract value is Rp. 222,017,999,900.65, SPI is 1.21 from the initial contract value Rp. 174,437,684,167.96

The Wells turbine is an ocean wave energy converter that has been implemented in several countries around the world. The hysteresis phenomenon, which causes a torque reduction when the rotor acquires air flow acceleration, is one of the Wells turbine's drawbacks. One enhancement strategy is converting the conventional Wells turbine, which operates in air, into a hydraulic Wells turbine, which operates in ocean water. This method aims to obtain a higher density of working fluid, which can increase the momentum acting on the Wells turbine blades. This research compared the performance and hysteresis phenomenon of conventional and hydraulic Wells turbines. A CFD method based on Reynolds Averaged Navier-Stokes (RANS) and k-ω SST turbulence model is used in this study. Under transient conditions, 3D modeling with periodic boundaries is applied to model the hysteresis phenomenon. This study demonstrated that the hydraulic Wells turbine outperforms the conventional Wells turbine. According to the simulation result, the hydraulic turbine achieves a significant improvement in maximum torque, approximately 124% of the conventional air turbine torque. The concept of immersing the Wells turbine in ocean water improves its efficiency as well. Furthermore, unlike the conventional one, the hydraulic Wells turbine does not exhibit hysteresis.

Pumps, especially centrifugal pumps, play an important role in engineering application, such as petroleum and petro-chemical industries, agricultural industries, portland cement industries etc. To obtain the best performance of the pumps, one has to operate the pumps at their design conditions. In some circumstances, however, the pumps must operate lower than their design conditions and result in the decrease in their performances. In such cases, it is possible to replace the pump impeller with the smaller impeller diameter or to cut its original impeller to smaller size as necessary. The cut of the impeller, or it is frequently referred to as impeller trimming, in some extence is preferable than replacing with new impeller or even by replacing with new pump with smaller head and capacity. In this study, we examine the effect of the pump impeller trimming to the pump performaces. The study was performed in the Fluid Mechanics Laboratory, Mechanical Engineering Department of ITS, Surabaya. The pump impellers were cut up to approximately 19 percent of its original pump impeller diameter, where the original pump impeller diameter is 129 mm. The pump has the maximum capacity of 100 liters/min and the total head of 31.5 m. The pump is powered by a 300 Watt electrical motor. Parameters to be studied in this research include pump capacity, pump head, pump power, and pump efficiency. The results of this study show that all data are in good agreement with the pump affinity laws. Pump capacity, pump head, and pump power decresase as the pump impeller diameter decreases. The pump efficiency is, however, in some extent, increases as the pump impeller diameter decreases. The maximum increase in pump efficiency is obtained when the ratio between the trimmed impeller to its original pump impeller diameter is approximately 89 percent (i.e. D2/D1 = 0.89), with the increase in pump efficiency of approximately 20 percent.

Sorghum is uniquely adapted to dryland and used by the Indonesian government to optimize the utilization of dryland and increase farmers’ incomes. The objective of this study was to analyze the contribution of sorghum to increasing income and the level of welfare of dryland farmer households in Wonogiri, Central Java, Indonesia. The study was conducted from October to December 2022 using a survey method through direct interviews with purposively selected sorghum-growing farmers. A set of questions included household income and expenditure. The average total income and expenditure indicators, poverty line figures, RMW, and ERFHI were used to measure the welfare level of farmer households. The study found that the income derived from sorghum contributes 22.87% to total household income and tends to increase household income by 29.65%. According to the average total income earned, farming households were in a prosperous condition. This can be seen from the total income, which is higher than the total expenditure, the average per capita income higher than the poverty line, the average total income higher than RMW, and the value of ERFHI at 1.25. Income derived from sorghum has increased by 21.43–56.00% from less prosperous households to prosperous ones. The results of this study are expected to contribute to the existing literature on sorghum development and farmers’ income and to be a reference for policy makers in formulating poverty alleviation programs and improving the welfare of farmer households, as well as expanding sorghum development by optimizing the utilization of agroecological, economic and social resources.

Rose water was water that has a distinctive flavor of rose and produced from the extraction of red rose petals using the steam distillation method. Red rose flowers have been used by some people as food. The purpose of this study was to determine the antioxidant activity of red rose water extract using Diphenyl Picril Hidrazil (DPPH) at various extraction times. The research method consisted of extraction of rose water by steam distillation at a pressure of 2 bar, phytochemical test including phenolic and vitamin C analysis, and antioxidant activity tests. The results of the phytochemical test showed that the extraction time for rose water was 75 minutes, the highest phenolic compound content was 115.04 ± 0.52 mg GAE/g and the highest vitamin C content was 2.201,67±2,89 mg/ 100 g. Based on the IC50 value of rose water extract according to the extraction time successively at the 75 minute was 49.46 ppm; at the 150 minute was 108.36 ppm; at the 225 minute it was 120.22 ppm and the 300 minute it was 160.78 ppm. This shows that rose water is classified as having very strong to moderate antioxidant activity

The perfect wing is a dream that many airplanes has manufactured have been striving to achieve since the beginning of the airplane design. There are some aspect that most influence in aircraft design lift, drag, thrust, and weight. The combination of these aspects leads to a decrease in fuel consumption, which reduces pollution in our atmosphere and increase in economic revenue. One way to improve aircraft performance is to modify the tip of the wing geometry, which has become a common sight on today’s airplanes. With computational programs, the effects on drag due to wingtip devices can be previewed. This research was done numerically by using turbulence model k-ω SST. Reynolds number in this research was 2,34 x 10 4 with angle of attacks are 0o, 2o, 4o, 6o, 8o, 10o, 12o, 15o, 17o and 19o. The model specimen is wing airfoil Eppler 562 with winglets. Two types of wingtips are used: forward and rearward wingtip fence. From this study, it was found that wingtip fence reduced the strength of vorticity magnitude on the x axis compared to plain wings. The leakage of fluid flow effect at the leading edge corner of the wingtip, giving pressure gradient and slightly shifting towards the trailing edge. this occurs in the plain wing and rearward wingtip fence but does not occur in the forward wingtip fence. .

Sorghum is an important food crop commodity in the midst of climate change conditions and the threat of a global food crisis. Sorghum, which has an adaptive advantage to all land conditions, is suitable for use as a food substitute for rice and wheat. The purpose of this study was to evaluate the economic value, farmers’ perceptions, and specific strategies for developing sorghum in Central Java and Yogyakarta, Indonesia. The research was conducted in Wonogiri Regency, Central Java, and Gunungkidul Regency, Yogyakarta from September to November 2022. The research was carried out through the observation of 120 respondents with indicators of farming characteristics and farmers’ perceptions of sorghum development, as well as focus group discussions (FGD) and depth interviews with indicators of internal and external factors for sorghum development. The analysis used is benefit cost (BC) to evaluate the economic value of sorghum farming, the Likert scale to determine farmers’ perceptions of sorghum, and Strength Weak Opportunity Threat (SWOT) to determine specific strategies for developing sorghum. The results showed that sorghum farming is feasible to develop in Wonogiri Central Java and Gunungkidul Yogyakarta because it provides a profit value greater than production costs with a BCR value of >1. The perception of farmers in Central Java regarding the development of sorghum is included in the very good category with an average value of 3.31, and the perception of farmers in Yogyakarta is included in the good category with an average value of 2.55. The operational policy strategy for developing sorghum in Wonogiri Central Java and Gunungkidul Yogyakarta is an expansion strategy (S-O).

A study on the utilization of biomass in power plants as an alternative fuel was conducted. The benefit of biomass fuel is that it reduces greenhouse gas emissions, namely carbon dioxide, and contributes to reducing the effects of global warming. This paper discusses the characterization of coal and empty fruit bunch (EFB) blends as well as the characteristics of EFB using TG-DTA (Thermo gravimetric-Differential Thermal Analyzer). The study was conducted at a heating rate of 20°C/min in reaction air and inert (nitrogen) gas up to 900°C. Combustion properties were analyzed by observing the combustion profile graph. The increasing heating rate can shorten the reaction time (in the same temperature region), and therefore the temperature required for the sample to decompose is higher. However, combustion reactivity was analyzed by the reactivity index, where the higher the value, the higher the combustion rate and the faster the combustion time. A higher reactivity value of coal and EFB blends relative to coal has the potential to reduce the unburned carbon content of fly ash.

The growth of the Indonesian population has led to an increase in the demand for rice, which the country has yet to satisfy. Indonesia needs a comprehensive strategy that integrates meaningful efforts to increase its agricultural production. This study aims to review the examined trends in rice yield in Indonesia for 70 years after Indonesia’s independence (1945–2016) followed by the identification of the application technology and factors that contribute to increasing rice yields to forecast sustainable food security scenarios up to 2030. This article reviews the results of research on rice production technology in Indonesia from 1945 to 2016, and the outlook for 2030. This paper examines the main points of the Indonesian transformation of rice technology: improvement of rice varieties, integrated crop management, innovations in agricultural machinery, and the Integrated Cropping Calendar Information System (ICCIS). We found that transformation has helped Indonesia increased its rice yields from 3 t ha−1 prior to 1961 to 4.6 t ha−1 in 1985, stagnated in 1990, and increased again in 2017 to 5.46 t ha−1. The increase in yield was sustained by an increase in the harvested area owing to cropping index (CI) innovation. Food security and sustainable development remain the primary goals of Indonesia’s agricultural sector. The application of appropriate technologies and institutional innovations can assist Indonesia in achieving its food security. Therefore, the transformation of technological innovations will continue to be an essential driver of future agricultural growth, including greater use of crop varieties, machinery, and land/institutional reforms.

Rice production in the karst dryland is still low, due to soil characteristics that lack nutrient availability. Meanwhile, upland rice has received less attention, and it has not been used to its full potential. This study aimed to evaluate the effect of various combinations of inorganic fertilizers, poultry manure, and upland rice varieties on the production and economic value of karst dryland in Gunungkidul, Yogyakarta. This experiment was arranged in a factorial design, with inorganic fertilizers, poultry manure, and upland rice varieties set in a randomized block design with three replications. The first factor was a combination of inorganic and organic fertilizer rates: 72 N kg ha−1 + 26 P2O5 kg ha−1 + 25 K2O ha−1 + 3 t ha−1 organic, 92 N kg ha−1 + 36 P2O5 kg ha−1 + 30 K2O kg ha−1 + 2 t ha−1 organic, 112 N kg ha−1 + 46 P2O5 kg ha−1 + 35 K2O kg ha−1 + 1 t ha−1 organic. The second factor is the upland varieties of Inpago 8, Inpago 10, and Inpago 12 and lowland variety Inpari 42 Agritan GSR, as checked. Based on the study, we concluded that the combination of 92 N kg ha−1 + 36 P2O5 kg ha−1 + 30 K2O kg ha−1 + 2 t ha−1 poultry manure fertilizers with Inpago 8 resulted in an IDR profit of 23,586,000 ha−1, and it is the most recommendable fertilizer and variety combination to be developed in the karst dryland, in consideration of land fertility and sustainability.

The aims of the study was to improve quality of cocoa bans by fermentation of sun dried cocoa beans. The fermentation variations were conducted as follows: first, fermentation without the addition of inoculum (control), the second treatment using inoculum of S. cerevisiae (FNCC 3056), L. lactis (FNC 0086) and A. aceti (FNCC 0016), each of 108 cfu/g given simultaneously at the beginning of fermentation.and the third treatment wassequential administration, i.e: yeast at the initial fermentation, lactic acid bacteria after 24 hours fermentation, and acetic acid bacteria after 48 hr of fermentation third with the same microbial population with the second treatment. The fermentation was conducted for120 hours. The fermentation temperature were controlled during fermentation as follows: 35 °C for the first 24 hours, 45 °C for the next second 24- hours, 55 °C the third 24 hours and 35 °C for the last 48 hours of fermentation. The results showed that after the rehydration, pulp composition of dry beans could be used as a substrate for fermentation. During fermentation, dry cocoa beans showed reduction of total sugar content, pH and total polyphenols for all the three treatments. Cut test of dried cocoa beans during the fermentation showed the increasing percentage of brown color of the three treatments. Reducing sugar and fermentation indexes increasedfor all treatments during fermentation. Concentration of ethanol, lactic acid and acetic acid reached highest level at 24, 60, and 108 hours of fermentationfor all treatments. Highest populations of S. cerevisiae, L. lactis and A. aceti of three treatments obtained at 24, 48 and 72 hours of fermentation. After fermentation and roasting, dry beans produced hydrophobic amino acids as precursors of flavor and volatile compounds. ABSTRAK Penelitian ini bertujuan untuk mengetahui perubahan sifat kimia pada fermentasi biji kakao kering jemur. Biji kakao kering jemur yang diperoleh dari petani memiliki kadar air yang tidak seragam. Guna menimalkan kegagalan fermentasi maka biji kakao kering jemur diperoleh melalui pengeringan biji kakao segar menggunakan kabinet dryer dengan sebelumnya dikondisikan pada suhu seperti pengeringan dengan sinar matahari, dan masing ditentukan kadar gula reduksinya. Percobaan fermentasi biji kakao kering dilakukan fermentasi pada wadah fermentasi dengan jumlah biji 150 g setiap wadah. Sebelum difermentasi terlebih dahulu biji kakao kering jemur direhidrasi agar didapat kadar air mendekati biji segar, kemudian biji kakao kering jemur diinkubasi selama enam hari dan tanpa dibalik selama fermentasi. Setiap perlakuan diulangi tiga kali dan diamati tiap 24 jam sampai 120 jam. Kadar gula reduksi (kontrol 4,49–11,45%, inokulum diawal (IA) 4,69–11,55%, inokulum bertahap (IB) 4,64–11,54%), kadar asam tertitrasi (kontrol 4,48–6,45%, inokulum diawal (IA) 4,64–6,39%, inokulum bertahap (IB) 4,45–6,59%), populasi Saccharomycescerevisiae (kontrol 5,56–7,28 (log CFU/g), inokulum diawal (IA) 6,45–8,75 (logCFU/g), inokulum bertahap (IB) 6.88 – 8.99 (logCFU/g), Lactobacillus lactis (kontrol 6,66–8,15 (log CFU/g), inokulum diawal (IA) 7,65–8,21(log CFU/g), inokulum bertahap (IB) 7,66–8,95 (log CFU/g) dan Acetobacter aceti (kontrol 4,26–6,95% (log CFU/g), inokulum diawal (IA) 4,85–7,40 (log CFU/g), inokulum bertahap (IB) 4,35–7,91 (log CFU/g)) dalam pulp fermentasi diamati selama proses fermentasi. Untuk mengetahui kualitas biji kakao dilakukan pengukuran pH (kontrol 5,67–3,98, inokulum diawal (IA) 5,67–3,55, inokulum bertahap (IB) 5,67–3,50), kadar etanol (kontrol 0,3–0,5%, inokulum diawal (IA) 0,3–0,52%, inokulum bertahap (IB) 0,35–0,53%) dan indeks fermentasi selama fermentasi (kontrol 0,31–0,88, inokulum diawal (IA) 0,32–0,99, inokulum bertahap (IB) 0,33–1,03). Kata kunci: Acetobacter aceti; biji kakao kering jemur; fermentasi; Lactobacillus lactis; Saccharomyces cerevisiae

The study aims to determine the effect of applying for intercropping food crops (rice, corn, and soybeans = jagole) on the cropping index and income of urban farming community activists. This study was conducted by comparing the use of six models of growing food crops, namely three kinds of monoculture model of jagole, upland rice-soybean, sweet corn-soybean, and sweet corn-upland rice polyculture/ “Turiman”. Observational data includes data on land characteristics, annual cropping patterns in related locations, and input-output data of the test models. Corn and soybeans are harvested young. Data were processed using descriptive analysis and the economic feasibility analysis of the tested technology was based on the R/C ratio. Based on data, it is known that there is potential to increase the cropping index of dry or limited land in the Jakarta area, from 1-2 to 2-3 a year by optimizing planting through intercropping systems/ food crop Turiman. such as corn-upland rice-soybean. The results of the analysis showed that the soybean monoculture technology model, with yields of young soybeans, gave a higher profit (R/C 2.58), compared to the other models, namely sweet corn monoculture, upland rice monoculture, upland rice-sweet corn polyculture, soybean-sweet corn polyculture, soybean-upland rice polyculture, and (R/C respectively: 0.24, 0.54, 0.17, 1.25, and 1.71).

Most cocoa beans produced by Indonesian farmers are non-fermented dry cocoa whose quality can be improved by the fermentation. However, it requires the optimization for fermentation process. This study was conducted to determine the effect of giving a pure culture of Saccharomyces cerevisiae, Lactobacillus lactis and Acetobacter aceti bacteria in fermented dry cocoa beans. Dry beans obtained by drying the wet (fresh) cocoa beans in the cabinet dryer, and subsequently their levels of reduction sugar were determined. The experiments of the fermentation of dry cocoa beans were conducted in a box (p = 120 cm, l = 80 cm, t = 40 cm) with aeration hole (diameter of 1 cm) and the distance between holes was 10 cm. Cocoa beans were incubated for 6 days and without inverted during fermentation. The studied treatments were A1 (without the addition of inoculum (control)), A2 (inocolum was added at the beginning of the incubation), A3 (inoculum was added at the beginning of fermentation (Saccharomyces cerevisiae). After 24 hours of experiment, Lactobacillus lactis was added while Acetobacter aceti was added after 48 hours. Each treatment was repeated three times and observed every two days. The levels of reducing sugars, etanol, acidity, yeasts and acetic acid bacteria population in the fermentation pulp/liquid were observed during the fermentation process. In order to determine the quality of dry beans, several aspects have been measured such as: pH, fermentation index and split test on dry beans after fermentation. ABSTRAK Sebagian besar biji kakao yang dihasilkan petani Indonesia merupakan kakao kering non-fermentasi yang kualitasnya masih dapat ditingkatkan dengan metode fermentasi, tetapi dibutuhkan optimasi agar fermentasi dapat berjalan dengan baik. Penelitian ini dilakukan untuk mengetahui pengaruh dari pemberian biakan murni murni Saccharomyces cerevisiae, Lactobacillus lactis dan Acetobacter aceti pada fermentasi biji kakao kering jemur. Biji kakao kering jemur diperoleh dengan mengeringkan biji kakao basah (segar) dalam kabinet dryer, dan ditentukan kadar gula reduksinya. Percobaan fermentasi biji kakao kering jemur dilakukan dalam kotak fermentasi (p = 120 cm, l = 80 cm, t = 40 cm) yang diberi lubang aerasi berdiameter 1 cm dan jarak antar lubang 10 cm. Biji kakao difermentasi selama 6 hari dan tanpa dibalik selama fermentasi. Perlakuan dalam penelitian ini adalah A1 (tanpa penambahan biakan murni murni (kontrol)), A2 (pemberian biakan murni murni diawal fermenatasi), A3 (pemberian biakan murni murni secara bertahap selama fermentasi (Saccharomyces cerevisiae), setelah jam ke 24 diberikan Lactobacillus lactis dan setelah jam ke 48 diberikan Acetobacter aceti. Setiap perlakuan diulangi tiga kali dan diamati tiap dua hari sekali. Kadar gula reduksi, kadar etanol, kadar asam tertitrasi, populasi khamir, dan bakteri asam asetat dalam pulp/cairan fermentasi diamati selama proses fermentasi. Untuk mengetahui kualitas biji kakao kering jemur dilakukan pengukuran pH, indeks fermentasi dan uji belah pada biji kakao kering jemur setelah fermentasi.

New Superior Varieties (VUB) is a cultivation technology innovation that is continuously being developed by Balitbangtan. The average production addition of inbred rice seed is about 1.5% per year. Inbred rice varieties include Inpari 62 varieties, Inpago 18 varieties, and Inpara 11 varieties. Currently, farmers have used 25 varieties of Inpari, and 5 varieties of Inpago. This means that the use of VUB at the farm level is not optimal yet. Therefore, the aim of this paper is to determine the determinants of VUB adoption in the rice productivity improvement program. Data were collected using a questionnaire filled out via google form from 30 BPTP. Respondents consisted of 180 researchers and 113 extension workers. Data were analyzed using Analytical Hierarchy Process. The results of the analysis showed that the success of VUB adoption is influenced by determinants such as: (i) the nature of VUB innovation according to farmers' preferences, (ii) easy seed distribution and (iii) dissemination by improving technical guidance. The use of VUB can be increased by taking into account: (i) user preferences and according to the location of planting, and (ii) involving local breeders in overcoming availability and serving as a pilot location.

Previous in vitro studies showed that nanoparticle extract of turmeric, zedoary, and garlic exhibit antibacterial activity against Mycoplasma gallisepticum (M. gallisepticum) which causes chronic respiratory disease (CRD) in chicken. This research aimed to determine the antibacterial activity of nanoparticles of Curcuma longa, Curcuma zedoaria, and Allium sativum extract to CRD infected chicken. In vivo test of antibacterial activity of turmeric, zedoary, and garlic nanoparticle in combination was conducted on chicken infected by M. gallisepticum and Escherichia coli (E.coli). Antibiotic control used was enrofloxacin. As many as 75 chickens were divided into 5 groups containing 15 chickens each. Group one consisted of healthy chickens (positive control); group two consisted of chickens that have been inoculated by bacteria (negative control); group three (treatment) were chickens inoculated by bacterium and given extract nanoparticle combination on day 7 of infection for 7 days; group four (prevention) were chickens inoculated by bacterium and given combination of extract nanoparticles on day 5 before infection for 14 days; group five were chickens inoculated with bacterium and given enrofloxacin antibiotics for 7 days. In vivo research results showed increased body weight and performance indicated by improvements in clinical signs, and gross pathology changes. The combination of three extract nanoparticles showed the best activity in controlling CRD in chicken, both as preventive and curative means.

Boundary layer akan terbentuk apabila aliran viscous melewati suatu kontur permukaan. Hal ini menyebabkan terjadinya gaya drag di kontur permukaan, oleh karena itu boundary layer yang terbentuk perlu dikontrol. Salah satu cara untuk mengkontrol boundary layer yang terbentuk adalah dengan memberi alur permukaan yang dilalui aliran. Pada penelitian ini, aliran yang dikaji adalah aliran boundary layer turbulen yang melintasi suatu pelat datar dengan alur melintang tipe-D. Alur tipe-D adalah tipe alur berbentuk persegi dengan kedalaman dan jarak antar alur yang sama, diletakan normal terhadap arah aliran. Penelitian ini dilakukan secara simulasi numerik. Terdapat 4 model yang disimulasikan yaitu pelat datar (smooth-wall), pelat beralur tipe-D ukuran 4mm, 10mm, dan 30mm . Bilangan Reynolds berdasarkan panjang pelat yaitu Rel = 2.16 x 106 dan kecepatan freestream pada inlet sebesar 10 m/s. Pemodelan numerik dilakukan menggunakan software Gambit 2.4.6 dan Fluent 6.3.26 dengan model 2ddp unsteady, viscous model standart k-epsilon. Berdasarkan hasil penelitian, penambahan alur tipe-D berbagai ukuran meningkatkan koefisien drag total dibanding pelat datar (smooth-wall). Pressure-gradient yang terbentuk didalam alur berkontribusi pada peningkatan ini walaupun nilai koefisien skin-friction mengalami penurunan. Tidak hanya koefisien drag total, tapi nilai intensitas turbulensi juga mengalami peningkatan dibanding pelat datar (smooth-wall). Didalam alur juga terbentuk vortex yang berkontribusi dalam penurunan koefisien skin-friction. Dari ketiga ukuran alur yang berbeda, ditemukan ukuran alur tipe-D ukuran 4mm memiliki nilai koefisien drag total yang lebih rendah daripada lainya.

The aim of this research was to determine the effects of type and amount of binder on the chemical and physical properties of sweet corn milk-like powder. Sweet corn milk-like powder was prepared from sweet corn kernel extracted with water with ratio of water and kernel of 2:1 (v/w), then dehydrated by spray dryer. Dextrin and arabic gum in various amount i.e. 2.5; 5.0; and 7.5% (w/v), respectively were added to the sweet corn milk-like before drying, and control was also made. The reducing sugar and total sugar, protein, fat, and moisture content, and as well as bulk density, colour, and solubility of the powder were then analyzed. The chemical and physical properties of sweet corn milk-like powder with addition of dextrin and arabic gum in the amount of 2.5; 5.0; and 7.5% (w/v) were significantly different (p > 0.05). According to all aspects studied, sweet corn milk-like powder with addition of dextrin in the amount of 2.5% was the best product of all, which had reducing sugar of 5.00% (db); total sugar 17.01% (db); protein13.67% (db); fat 5.97% (db); moisture 5.38%; bulk density 0.47 g/cm3; and solubility of 93.70%.

Winglet is a tool used to improve the efficiency of aircraft and UAV performance by preventing fluid flow jump from lower surface to upper surface at wingtip. The addition of this winglet resulted in improved lift and reduction of drag force from the aircraft wing or UAV. From Whitcomb's research, it was found that the use of winglet on a full size airplane can increase fuel efficiency by 7%. The research led to the idea of conducting research on fluid flow characteristics on the UAV wing with the Eppler 562 airfoil combined with the whitcomb winglet. This numerical study was conducted using the Computational Fluid Dynamics (CFD) method based on the advantages of using this simulation that can review the fluid flow in macroscopic way. This study is provide accurate fluid flow visualization results and can improve the performance of the wings when compared with wings without winglet (plain wing). Wing with the Eppler 562 airfoil combined with the whitcomb winglet results reduction in rotating motion that makes velocity components as opposed to lift.

Low access to credit in the agricultural sector is also caused by problems of agricultural sector actors (especially farmers) and financial institutions. Farmers are still having difficulty in accessing credit (accessibility and unbankable) and the limited financial institutions that channel credit to the agricultural sector. Therefore, the government must issue a policy in growing the agricultural sector, especially in anticipation of access credit constraints by farmers. The agricultural sector as a high-risk business, therefore formal institutions are less interested in financing the agricultural sector on the grounds of high transaction costs, asymmetric information, low profits, lack of collateral, education of farmers is relatively low. In addition, most banks do not want to finance agriculture due to fluctuating production and uncontrolled price risk. While the constraints of the farmers in obtaining formal credit is a complex procedure, there should be collateral as well as high payment delay fees, long distances and less information about capital.

The research is aimed to study the effect of heat of microwave in the preparation of reclaimed rubber from used tire and the application of rubber compound observed from the characteristics of its vulcanization. Reclaimed rubber is found from used tire treads that ground and shifted using 10 mesh of shifter. Devulcanization was carried out in microwave with power output from 0, 100 – 200 watt. The reclaimed rubber was used as the natural rubber substitute, with proportion of 20, 40, and 60 parts per hundred of rubber. The cracteristic of the compound was tested by using Rheometer whereas the reactivity of the rubber against the Vulcanizing agents was observed by using Fourier Transform Infrared Spectrophotometer. The results showed that reclaimed rubber prepared by heating in microwave with power output of 100 and 200 watt as well as without heating treatment showed significant effect to characteristic of vulcanization. Proportion of utilization of reclemed rubber as much as 20,40 and 60 parts showed significant effect to characteristic of vulcanization. Proportion of 40 part reclaimed rubber prepared by microwave heating with power output 100 watt showed the best characteristic of vulcanization.

The objectives of the research were to determine the chemical and physical characteristics of purple-flesh sweet potato flour as base of suitability for processed foods production, and to determine the acceptability of products by panelists. Cookies and pound cake were made by using purple-flesh sweet potato flour as raw material and using stages of process as follows: dough preparation, molding, shaping and baking. The results showed that purple-flesh sweet potato flour contain moisture 10.92 ± 0.09 % (db), protein 6.44 ± 0.27 % (db), starch 74.57 ± 0.32 % (db), amylose 24.79 ± 0.94 % (db), reducing sugar 3.15 ± 0.30 % (db), and crude fiber 2.40 ± 0.35 % (db). Peak viscosity at 65 oC was 6.17 dPa.s and setback viscosity was similar to the peak viscosity. Starch granules of purple-flesh sweet potato were polygonal with size of 10-25 μm. The cookies made by using mixture of 25 % wheat flour and 75 % purple-flesh sweet potato flour, and pound cake made by using 100 % purple-flesh sweet potato flour were acceptable for panelists. Keywords: Purple-flesh sweet potato flour, cookies, pound cake Abtrak Tujuan penelitian adalah untuk mengetahui karakteristik kimia dan fisik tepung ubi jalar ungu sebagai dasar penentuan kesesuaian untuk pembuatan pangan olahan berbasis tepung ubi jalar ungu serta untuk mengetahui tingkat penerimaan panelis. Tepung ubi jalar ungu diolah menjadi cookies dan pound cake mengikuti tahap penyiapan adonan, pencetakan, dan pemanggangan. Dilakukan uji inderawi cookies dan pound cake melalui uji kesukaan oleh panelis yang meliputi parameter warna, aroma, cita-rasa, tekstur, dan kesukaan keseluruhan serta uji deskriptif. Hasil penelitian menunjukkan bahwa tepung ubi jalar ungu memiliki berturut-turut komponen kadar air 10,92 ± 0,09 % (bk), protein 6,44 ± 0,27 % (bk), pati 74,57 ± 0,32 % (bk), amilosa 24,79 ± 0,94 % (bk), gula reduksi 3,15 ± 0,30 % (bk), dan serat kasar 2,40 ± 0,35 % (bk). Viskositas puncak tepung ubi jalar ungu pada suhu 65 oC sebesar 6,17 dPa.s, dan viskositas baliknya relatif sama dengan viskositas puncak. Granula pati tepung ubi jalar ungu berbentuk poligonal dengan ukuran 10-25 μm. Cookies yang dibuat dari kombinasi antara tepung terigu 25 % dan tepung ubi jalar ungu 75 %, dan pound cake yang dibuat dari tepung ubi jalar ungu 100 % (tanpa tepung terigu) cukup disukai panelis. Kata kunci: Tepung ubi jalar ungu, cookies, pound cake

Development in hydropower technology leads to modern and efficient technology. The emergence of gravitational vortex water turbine (GVWT) is a promising invention. It is suitable for harnessing energy from low head and flow rate water sources, ranging from approximately 0.7–2 m and 0.03–5 m3/s. A series of experimental studies had been conducted to develop the GVWT with a propeller runner. The objective of this study is to analyze the effect of runner design, including the number of blades, runner diameter and runner installation position, on the GVWT's performance. A preliminary study on a dual-stage GVWT was carried out to increase the single-stage GVWT performance. The experimental result shows that 4-blade and 5-blade runners provide better performance than 3-blade runner and 6-blade runner. For a 5-blade runner, the optimal installation position is between 60% and 70% of depth. Installing a runner in the basin produces a blockage effect, which increase the runner performance. An extremely large blockage ratio causes stoppage which is undesirable. The maximum allowed blockage ratio is 0.8. The preliminary study on the dual-stage GVWT proves that it increases the GVWT's performance. The efficiency of GVWT ranges from 25% − 50%. [ABSTRACT FROM AUTHOR]

Shallots have been used for generations as traditional medicine, one of which is used in the treatment of diarrhea. This study determined the antidiarrheal activity of the shallot bulbs using intestinal protection and intestinal transit methods, and to determine the effective concentration that gives the best antidiarrheal effect in mice. This study used thirty mice and divided into six groups. The negative control group was given Tween 80 (1%), positive control group was given Loperamide HCl, and four various concentrations of shallot infusion treatment groups (1.25%, 2.5%, 5%, and 10 %). The treatment was given by the oral route. The parameters used in the intestinal protection method were frequency of defecation and feces consistency, while in intestinal transit method the parameters used were the percentage ratio of the marker trajectories compared to the overall length of the intestine. The results showed that the 1.25% concentration of shallot infusion indicated the best antidiarrheal activity and had a smaller ratio or stronger inhibition to intestinal peristaltic compared to all other concentrations, 2.5%, 5%, dan 10%. We concluded that shallot bulbs infusion with a concentration of 1.25% has the most effective anti-diarrheal effect. This research can be continued by measurement of other diarrheal parameters such as stool weight, as well as start and stop time of diarrhea to further clarify the anti-diarrheal potential of shallot bulb infusion.

This study investigates the co-gasification of municipal solid waste (MSW) and coconut shell (CS) using natural zeolite catalysts, with a focus on elucidating physicochemical properties, syngas composition, and potential synergistic effects to enhance energy production performance. Proximate and ultimate analyses of MSW and CS delineate distinctive properties, guiding optimized co-processing. Natural zeolite catalysts, identified as mordenite, clinoptilolite, and alpha quartz via XRD analysis, introduce a novel dimension with potential catalytic influences on gasification products. Experimental assessments reveal the nuanced impact of varying biomass ratios on syngas composition, showcasing significant shifts in CO, CH4, and H2 concentrations quantified through gas chromatography. Flame color visualizations, captured quantitatively in real-time, provide immediate indicators of flammable gas presence during co-gasification scenarios, offering insights into process dynamics. Residue analyses, quantified across different biomass ratios, delineate tar, char, and gas distributions, informing optimization strategies. XRD analysis of chars at 750°C quantitatively illustrates microcrystalline structures and potential catalytic implications of CaCO3 in the presence of MSW. This study bridges theoretical and practical dimensions, providing quantitative insights into the gasification process, syngas composition, and residue management. Emphasizing the potential of co-gasification with natural zeolite catalysts, it contributes substantial quantitative data, positioning itself as a scientific reference for advancing waste-to-energy processes and optimizing biomass utilization. The study underscores the importance of synergistic effects in achieving enhanced performance and sustainability in waste-to-energy conversion. [ABSTRACT FROM AUTHOR]

Sorghum (Sorghum bicolor L. Moench) is an essential food crop for more than 750 million people in tropical and sub-tropical dry climates of Africa, India, and Latin America. The domestic sorghum market in Indonesia is still limited to the eastern region (East Nusa Tenggara, West Nusa Tenggara, Java, and South Sulawesi). Therefore, it is crucial to carry out sorghum research on drylands. This research aimed to investigate the effect of sorghum genotype and planting distance and their interaction toward growth and sorghum’s productivity in the Gunungkidul dryland, Yogyakarta, Indonesia. In addition, the farm business analysis, including the feasibility of sorghum farming, was also examined. The research used a randomized complete block design (RCBD), arranged in a 5 × 4 factorial with 3 replicates. The first treatment consisted of 5 varieties (2 high-yielding varieties (Bioguma 1 and Kawali) and 3 local sorghum varieties (Plonco, Ketan Merah, and Hitam Wareng)). The second treatment consisted of 4 levels of planting distance, namely 50 × 20 cm, 60 × 20 cm, 70 × 15 cm, and 70 × 20 × 20 cm. Analysis of variance was used to analyze the data, where Duncan’s multiple range test (DMRT) was used post hoc. Plant height, panicle height, panicle width, panicle weight, stover weight, grains weight/plot, and productivity were significantly affected by sorghum varieties (p < 0.05). However, there was no significant effect from the planting distance treatment and no interaction between planting distance and varietal treatments. Ketan Merah had the highest height, panicle length, and panicle width, while Bioguma 1 had the highest stover weight, panicle weight, grain weight/plot, and productivity. There was a significant linear regression equation, i.e., productivity = 0.0054– 0.0003 panicle height + 0.4163 grains weight/plot. Our findings on farm business analysis suggested that four out of five tested sorghum varieties were feasible to grow, except for the Ketan Merah variety. The most economically profitable sorghum variety to grow in Gunungkidul dryland was Bioguma 1. [ABSTRACT FROM AUTHOR]