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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.

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 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).

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.

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.

Nanophytosome from the combination of Merbau wood (Intsia sp.) and Gotu Kola leaves (Centella asiatica) extracts (NMG) have the potential as natural active ingredients of antiaging creams. This study aims to analyze the preference level of creams with the active ingredient of 4% NMG and the additions of essential oils and to test the physicochemical stability of the most preferred cream. The cream added the essential oil of nutmeg leaf, kaffir lime peel, and lime peel at consentration of 0%, 0.5%, 1%, and 1.5% (w/w). The preference level was measured by hedonic rating tests on the scent, texture, and viscosity by 30 non-standard panelists aged ≥25 years. The most preferred formula was tested for physicochemical stability by storage at low temperature (±4 °C), room temperature (±27 °C), and extreme temperature (±40 °C) for 21 days. The results showed that the most preferred formula was F9, which used 1% kaffir lime peel essential oil. The higher the temperature, the spreadability of the cream will increase; conversely, the higher the storage temperature, the lower the pH value, viscosity and stickiness of the cream, but it still meets the physicochemical standard of cosmetics cream. So this antiaging cream can be used for cosmetic applications.