期刊文献+
共找到33篇文章
< 1 2 >
每页显示 20 50 100
Value Function Mechanism in WSNs-Based Mango Plantation Monitoring System
1
作者 Wen-Tsai Sung Indra Griha Tofik Isa Sung-Jung Hsiao 《Computers, Materials & Continua》 SCIE EI 2024年第9期3733-3759,共27页
Mango fruit is one of the main fruit commodities that contributes to Taiwan’s income.The implementation of technology is an alternative to increasing the quality and quantity of mango plantation product productivity.... Mango fruit is one of the main fruit commodities that contributes to Taiwan’s income.The implementation of technology is an alternative to increasing the quality and quantity of mango plantation product productivity.In this study,a Wireless Sensor Networks(“WSNs”)-based intelligent mango plantation monitoring system will be developed that implements deep reinforcement learning(DRL)technology in carrying out prediction tasks based on three classifications:“optimal,”“sub-optimal,”or“not-optimal”conditions based on three parameters including humidity,temperature,and soil moisture.The key idea is how to provide a precise decision-making mechanism in the real-time monitoring system.A value function-based will be employed to perform DRL model called deep Q-network(DQN)which contributes in optimizing the future reward and performing the precise decision recommendation to the agent and system behavior.The WSNs experiment result indicates the system’s accuracy by capturing the real-time environment parameters is 98.39%.Meanwhile,the results of comparative accuracy model experiments of the proposed DQN,individual Q-learning,uniform coverage(UC),and NaÏe Bayes classifier(NBC)are 97.60%,95.30%,96.50%,and 92.30%,respectively.From the results of the comparative experiment,it can be seen that the proposed DQN used in the study has themost optimal accuracy.Testing with 22 test scenarios for“optimal,”“sub-optimal,”and“not-optimal”conditions was carried out to ensure the system runs well in the real-world data.The accuracy percentage which is generated from the real-world data reaches 95.45%.Fromthe resultsof the cost analysis,the systemcanprovide a low-cost systemcomparedtothe conventional system. 展开更多
关键词 Intelligent monitoring system deep reinforcement learning(DRL) wireless sensor networks(WSNs) deep Q-network(DQN)
下载PDF
Investigation of contact behavior on a model of the dual-mobility artificial hip joint for Asians in different inner liner thicknesses
2
作者 Taufiq Hidayat Muhammad Imam Ammarullah +5 位作者 Rifky Ismail Eko Saputra M Danny Pratama Lamura Chethan K N Athanasius Priharyoto Bayuseno J Jamari 《World Journal of Orthopedics》 2024年第4期321-336,共16页
BACKGROUND The four components that make up the current dual-mobility artificial hip joint design are the femoral head,the inner liner,the outer liner as a metal cover to prevent wear,and the acetabular cup.The acetab... BACKGROUND The four components that make up the current dual-mobility artificial hip joint design are the femoral head,the inner liner,the outer liner as a metal cover to prevent wear,and the acetabular cup.The acetabular cup and the outer liner were constructed of 316L stainless steel.At the same time,the inner liner was made of ultra-high-molecular-weight polyethylene(UHMWPE).As this new dual-mobility artificial hip joint has not been researched extensively,more tribological research is needed to predict wear.The thickness of the inner liner is a significant component to consider when calculating the contact pressure.AIM To make use of finite element analysis to gain a better understanding of the contact behavior in various inner liner thicknesses on a new model of a dual-mobility artificial hip joint,with the ultimate objective of determining the inner liner thickness that was most suitable for this particular type of dual-mobility artificial hip joint.METHODS In this study,the size of the femoral head was compared between two diameters(28 mm and 36 mm)and eight inner liner thicknesses ranging from 5 mm to 12 mm.Using the finite element method,the contact parameters,including the maximum contact pressure and contact area,have been evaluated in light of the Hertzian contact theory.The simulation was performed statically with dissipated energy and asymmetric behavior.The types of interaction were surface-to-surface contact and normal contact behavior.RESULTS The maximum contact pressures in the inner liner(UHMWPE)at a head diameter of 28 mm and 36 mm are between 3.7-13.5 MPa and 2.7-10.4 MPa,respectively.The maximum von Mises of the inner liner,outer liner,and acetabular cup are 2.4–11.4 MPa,15.7–44.3 MPa,and 3.7–12.6 MPa,respectively,for 28 mm head.Then the maximum von Mises stresses of the 36 mm head are 1.9-8.9 MPa for the inner liner,9.9-32.8 MPa for the outer liner,and 2.6-9.9 MPa for the acetabular cup.A head with a diameter of 28 mm should have an inner liner with a thickness of 12 mm.Whereas the head diameter was 36 mm,an inner liner thickness of 8 mm was suitable.CONCLUSION The contact pressures and von Mises stresses generated during this research can potentially be exploited in estimating the wear of dual-mobility artificial hip joints in general.Contact pressure and von Mises stress reduce with an increasing head diameter and inner liner’s thickness.Present findings would become one of the references for orthopedic surgery for choosing suitable bearing geometric parameter of hip implant. 展开更多
关键词 Contact behavior Contact pressure Finite element analysis Dual-mobility Artificial hip joint
下载PDF
Overview of Jute Fibre as Thermoplastic Matrix Polymer Reinforcement
3
作者 Tezara Cionita Mohammad Hazim Mohamad Hamdan +9 位作者 Januar Parlaungan Siregar Deni Fajar Fitriyana Ramli Junid Wong Ling Shing Jamiluddin Jaafar Agustinus Purna Irawan Teuku Rihayat Rifky Ismail Athanasius Priharyoto Bayuseno Emilianus Jehadus 《Journal of Renewable Materials》 EI CAS 2024年第3期457-483,共27页
Recent decades have seen a substantial increase in interest in research on natural fibres that is aligned with sustainable development goals(SDGs).Due to their renewable resources and biodegradability,natural fiberrei... Recent decades have seen a substantial increase in interest in research on natural fibres that is aligned with sustainable development goals(SDGs).Due to their renewable resources and biodegradability,natural fiberreinforced composites have been investigated as a sustainable alternative to synthetic materials to reduce the usage of hazardous waste and environmental pollution.Among the natural fibre,jute fibre obtained from a bast plant has an increasing trend in the application,especially as a reinforcement material.Numerous research works have been performed on jute fibre with regard to reinforced thermoset and thermoplastic composites.Nevertheless,current demands on sustainable materials have required new developments in thermoplastic composites.In this paper,the author reviews jute plants as reinforcement materials for thermoplastic matrix polymers.This review provides an overview of the sustainability of jute plants as reinforcement material for thermoplastic matrix polymers.The overview on jute based thermoplastic composites focused on the thermal behavior and mechanical properties.Apart from physical,chemical,and mechanical properties,the study also covers the current and perspectives for future research challenges faced by the researchers on jute fibre reinforced thermoplastic composites. 展开更多
关键词 Jute fibre sustainable development goals(SDGs) natural fibre THERMOPLASTIC composite sustainable manufacturing
下载PDF
An IoT-Based Aquaculture Monitoring System Using Firebase
4
作者 Wen-Tsai Sung Indra Griha Tofik Isa Sung-Jung Hsiao 《Computers, Materials & Continua》 SCIE EI 2023年第8期2179-2200,共22页
Indonesia is a producer in the fisheries sector,with production reaching 14.8 million tons in 2022.The production potential of the fisheries sector can be optimally optimized through aquaculture management.One of the ... Indonesia is a producer in the fisheries sector,with production reaching 14.8 million tons in 2022.The production potential of the fisheries sector can be optimally optimized through aquaculture management.One of the most important issues in aquaculture management is how to efficiently control the fish pond water conditions.IoT technology can be applied to support a fish pond aquaculture monitoring system,especially for catfish species(Siluriformes),in real-time and remotely.One of the technologies that can provide this convenience is the IoT.The problem of this study is how to integrate IoT devices with Firebase’s cloud data system to provide reliable and precise data,which makes it easy for fish cultivators to monitor fishpond conditions in real time and remotely.The IoT aquaculture fishpond monitoring use 3 parameters:(1)water temperature;(2)pHwater level;and(3)turbidity level of pond water.IoT devices use temperature sensors,pH sensors,and turbidity sensors,which are integrated with a microcontroller and Wi-Fi module.Data from sensor readings are sent to the Firebase cloud via theWi-Fi module so that it can be accessed in real time by end users with an Androidbased mobile app.The findings are(1)the IoT-based aquaculture monitoring system device has a low error rate in measuring temprature,pH,and turbidity with a percentage of 1.75%,1.94% and 9.78%,respectively.Overall,the total average error of the three components is 4.49%;(2)in cost analysis,IoT-based has a cost-effectiveness of 94.21% compared to labor costs.An IoT-based aquaculture monitoring system using Firebase can be effectively used as a technology for monitoring fish pond conditions in real-time and remotely for fish cultivators that contribute to providing an IoT-based aquaculture monitoring system that produces valid data,is precise,is easy to implement,and is a low-cost system. 展开更多
关键词 Internet of Things aquaculture technology water monitoring system real-time database aquaculture monitoring system
下载PDF
Engine Performance Using Blended Fuels of Biodiesel and Eco Diesel
5
作者 Muhammad Idris IHusin +4 位作者 Indra Hermawan Uun Novalia RDBatubara Nugroho Agung Pambudi Alfan Sarifudin 《Energy Engineering》 EI 2023年第1期107-123,共17页
Diesel engines is an internal combustion engine with high thermal efficiency,which also uses biodiesel fuel,an environmentally friendly,non-toxic,and low sulfur content.Biodiesel has been around for a long time due to... Diesel engines is an internal combustion engine with high thermal efficiency,which also uses biodiesel fuel,an environmentally friendly,non-toxic,and low sulfur content.Biodiesel has been around for a long time due to its similar characteristics to diesel fuels which has limited availability.However,several disadvantages are associated with biodiesel,such as poor volatility and high viscosity,which reduces engine performance.Therefore,this study was carried out to improve the diesel engine performance by mixing biodiesel with ecodiesel(ED),an additive produced from natural ingredients that is dissolvable in biodiesel.The biodiesel fuel properties used are density 860 kg/m3,dynamic viscosity 4.50E-06 m2/s,cetane number 45,and flashpoint 52°C.The results showed that biodiesel-ED mixture could improve engine performance and the optimum performance was at a speed of 3000 rpm on 43.30(kW),124.93(N.m)of the engine torque,and 2.45E–5(kg/kW.s)of the specific fuel consumption.According to paired sample t-test,the difference in the engine performance is only experienced in the torque,which has a significant increase in the composition of the biodiesel+ED by 0.07 gr mixture. 展开更多
关键词 CAR vehicle EXPERIMENT COMBUSTION ED renewable energy
下载PDF
Properties of Wear Rate of Composites Made of Carbon Powder with a Matrix of Waste Glass 被引量:1
6
作者 Agus Edy Pramono Indriyani Rebet +2 位作者 Sidiq Ruswanto Anne Zulfia Johny Wahyuadi Soedarsono 《材料科学与工程(中英文A版)》 2012年第11期669-676,共8页
关键词 复合材料 磨损率 废玻璃 碳粉 粉末粒度 矩阵 属性 网目尺寸
下载PDF
Effect of the Density to the Electrical Conductivity of Carbon-Carbon Composite Made of the Mixture of Organic Waste Carbon 被引量:1
7
作者 Agus Edy Pramono Anne Zulfia Johny Wahyuadi Soedarsono 《材料科学与工程(中英文A版)》 2012年第5期402-409,共8页
关键词 碳复合材料 混合物 导电性 有机废弃物 密度 电导率值 煤焦油沥青 混合煤
下载PDF
Effect of the Composition Ratio Against the Electrical Conductivity Properties and the Wear Rate of the Composite
8
作者 Agus Edy Pramono 《材料科学与工程(中英文B版)》 2013年第11期700-706,共7页
关键词 碳纤维复合材料 导电性能 磨损率 玻璃复合体 废玻璃瓶 酚醛树脂 碳化碳 混合物
下载PDF
Generalized Normalized Euclidean Distance Based Fuzzy Soft Set Similarity for Data Classification
9
作者 Rahmat Hidayat Iwan Tri Riyadi Yanto +2 位作者 Azizul Azhar Ramli Mohd Farhan Md.Fudzee Ansari Saleh Ahmar 《Computer Systems Science & Engineering》 SCIE EI 2021年第7期119-130,共12页
Classification is one of the data mining processes used to predict predetermined target classes with data learning accurately.This study discusses data classification using a fuzzy soft set method to predict target cl... Classification is one of the data mining processes used to predict predetermined target classes with data learning accurately.This study discusses data classification using a fuzzy soft set method to predict target classes accurately.This study aims to form a data classification algorithm using the fuzzy soft set method.In this study,the fuzzy soft set was calculated based on the normalized Hamming distance.Each parameter in this method is mapped to a power set from a subset of the fuzzy set using a fuzzy approximation function.In the classification step,a generalized normalized Euclidean distance is used to determine the similarity between two sets of fuzzy soft sets.The experiments used the University of California(UCI)Machine Learning dataset to assess the accuracy of the proposed data classification method.The dataset samples were divided into training(75%of samples)and test(25%of samples)sets.Experiments were performed in MATLAB R2010a software.The experiments showed that:(1)The fastest sequence is matching function,distance measure,similarity,normalized Euclidean distance,(2)the proposed approach can improve accuracy and recall by up to 10.3436%and 6.9723%,respectively,compared with baseline techniques.Hence,the fuzzy soft set method is appropriate for classifying data. 展开更多
关键词 Soft set fuzzy soft set CLASSIFICATION normalized euclidean distance SIMILARITY
下载PDF
Application of Physics Phenomenon Model Towards Economic Symptoms in Indonesia (Spring Oscillation Model and Rupiah Rate Exchange)
10
作者 Kunlestiowati H. Nani Yuningsih Sardjito 《Economics World》 2018年第2期133-141,共9页
A physical phenomenon can be duplicated similarly to different phenomenon. Based on these facts, the application of physics phenomenon model towards the economic cases that occurred in Indonesia will be discussed. Phy... A physical phenomenon can be duplicated similarly to different phenomenon. Based on these facts, the application of physics phenomenon model towards the economic cases that occurred in Indonesia will be discussed. Physical phenomenon to be discussed is the loaded oscillation spring, while the economic case is the dynamics of the Rupiah against foreign currencies, namely U.S. Dollars. Symptoms of the analyzed oscillations involve vibration load on the spring, with the mass load changes against time; for free oscillation, damped oscillation, forced oscillation, as well as forced damped oscillation. Oscillation is modeled into a non homogenous second order differential equation, which results in a solution of the deviation function of time in the form of logarithmic harmonic function. Obtained solutions of physical phenomenon model are matched with the dynamics of the exchange rate data for both steady state, as well as to the condition shortly after the surge (crash). Models are quite satisfactory, especially when being associated with the occurrence of momentary interruption followed by a relaxation mechanism, both for amplitude and period. 展开更多
关键词 spring oscillations mass change exchange rate logarithmic harmonic function
下载PDF
Effect of HP Process Temperature on the Density and Porosity of Carbon-Carbon Composites Made of Coal Waste Powder
11
作者 Agus Edy Pramono Anne Zulfia Johny Wahyuadi Soedarsono 《材料科学与工程(中英文B版)》 2011年第3期316-322,共7页
关键词 碳复合材料 温度变化 煤矸石粉 高密度 孔隙率 HP 低孔隙度 煤焦油沥青
下载PDF
Accounting of Foreign Currencies: Difference in Exchange Transactions and Relation With Taxation of Indonesia (Case Study in Fishery Company)
12
作者 Ilham Hidayah Napitupulu Abdul Rahman Dalimunthe 《Journal of Modern Accounting and Auditing》 2013年第5期609-615,共7页
Future need of globalization in business is no longer focused on the local transaction; instead, it has involved many countries so as to affect the exchange rate of rupiah against foreign currencies. As a result, diff... Future need of globalization in business is no longer focused on the local transaction; instead, it has involved many countries so as to affect the exchange rate of rupiah against foreign currencies. As a result, differences in the exchange rate will lead to foreign exchange, be it a foreign exchange gain or foreign exchange losses. Exchange rate used at the beginning of the transaction is the exchange rate on the transaction, but in Indonesian currency transactions, what is often used is the exchange rate issued by the Directorate General of Taxation (DGT). If at the end of the period, a balance of foreign currency still exists, then it will be adjusted using a fixed rate or an exchange rate of Central Bank of Indonesia. The results showed that the treatment of foreign exchange at the fishery company was using both the exchange rate allowed in the accounting and taxation regulations in Indonesia. The balance of transactions is related to export, be it a balance of accounts receivable on the sale of the outstanding balance of exports and export freight carried at the exchange rate adjustment of Central Bank of Indonesia, subsequent transactions relating to the purchase of imports were adjusted to a fixed exchange rate, which means that the balance payable on imports will continue to use the exchange rate at the beginning of the transaction 展开更多
关键词 accounting for foreign exchange exchange rate TAXATION
下载PDF
Drying Characteristic of Anchovy Fish
13
作者 Rahmat Subarkah Abdurrachim +1 位作者 Jooned Hendrarsakti Belyamin 《Journal of Food Science and Engineering》 2013年第2期87-93,共7页
This paper focuses on the drying characteristic of anchovy fish (Anchovia engraulidae). It is necessary to understand the drying behavior, quality of the products and time required to optimize the energy consumption... This paper focuses on the drying characteristic of anchovy fish (Anchovia engraulidae). It is necessary to understand the drying behavior, quality of the products and time required to optimize the energy consumption of the process. The optimum velocity and temperature of drying air for good quality dried anchovy fish was determined. In average, the fish are 7 cm in length and 3.0-3.5 g in mass. Although some research on fish drying has been done, the study of drying of anchovy fish and its characteristic has not been well reported. The fish to be dried were arranged on 15 × 15 cm2 tray in the drying chamber of 17 × 30 cm2. The hot air of 40 -70 ℃ was delivered parallel to the tray with the velocity of 0.6 and 0.9 m s-1. It is found that thermal conductivity (k) and specific heat (cp) of anchovy fish are function of the moisture content (MC). The higher moisture content results in higher thermal conductivity and specific heat. Critical water content is also found in this experiment as well as the optimum drying condition. Drying rate period of anchovy fish will change from the constant drying rate period to the falling drying rate period when critical moisture content is about 48.8%-50.3% (wet basis). At these experiments, there is no case-hardening, even at temperature of 70 ℃. To achieve the optimum result, the drying process should be implemented in three steps, drying process at 70 ℃ for 150 min followed by drying at 50℃ for 100 min, and finally drying at 40℃ till achieving equilibrium moisture content. This research will contribute to improvement of drying method to achieve good quality of dried fish. 展开更多
关键词 Anchovy fish drying characteristic drying optimization.
下载PDF
A new empirical equation of shear wave velocity to predict the different peak surface accelerations for Jakarta city
14
作者 Munirwansyah Munirwansyah Mohamad Ali Fulazzaky +3 位作者 Halida Yunita Reza Pahlevi Munirwan Jonbi Jonbi Kasni Sumeru 《Geodesy and Geodynamics》 2020年第6期455-467,共13页
Site condition and bedrock depth play important roles in the determination of peak surface acceleration(PSA)values by earthquake motions.The soil parameters of shear wave velocity(Vs)and standard penetration test-numb... Site condition and bedrock depth play important roles in the determination of peak surface acceleration(PSA)values by earthquake motions.The soil parameters of shear wave velocity(Vs)and standard penetration test-number(N)value for Jakarta city are available up to 100 m below the Earth’s surface even though the typical depths to bedrock are in excess of 100 m.This study referred to the base motion peak ground acceleration(PGA)values of 0.100 g,0.218 g and 0.378 g to predict the PSA values using the Nonlinear Earthquake site Response Analysis(NERA)to analyse a simulated dataset for the bedrock depths of 100 m,200 m,300 m,400 m and 500 m with conditioned by clayey and sandy soils.A new empirical equation of Vs=102.48 N0.297(m/s)was proposed to calculate the values of Vsused as an input parameter in the NERA programme for the prediction of seismic wave propagation.The results showed that the PSA values are dependent on the amplitude of seismic waves,depths of bedrock and the local site conditions.Changes in the PSA values from 41.0%to 51.5%and from 46.1%to 79.8%for the bedrocks overlain by sand,from 20.0%to 42.1%and from 45.9%to 58.8%for the bedrocks overlain by clay with increasing of bedrock depths from 200 m to 300 m and from 400 m to 500 m,respectively,were predicted for a 2500-year return period earthquake.Decreases in the PSA values by 41.0%,51.5%,46.1%,79.8%for the bedrocks overlain by sand and by 20.0%,42.1%,45.9%,58.8%for the bedrocks overlain by clay were predicted for a 2500-year return period earthquake due to the bedrock depth changes of 200 m,300 m,400 m,500 m.Large-magnitude earthquake of Jakarta city has a significant effect on an increase or a decrease of the PSA value with depth of bedrock and may cause the vibration damage to buildings and other constructions on the ground.The analysis of the PSA value and PSA ratio influenced by the PGA value,bedrock depth and local soil conditions will make a contribution to the design of earthquake-safe building for Jakarta city in the future. 展开更多
关键词 Bedrock depth Clayey soil Jakarta city Peak ground acceleration Peak surface acceleration Sandy soil
下载PDF
Nutritional Composition and Topoisomerase Inhibitor Activity of Ethnomedicinal Marine Mollusk Nerita albicilla
15
作者 Linawati Hardjito Dani Sjafardan Royani Joko Santoso 《Journal of Food Science and Engineering》 2012年第10期550-556,共7页
DNA topoisomerases (topo) I and II are molecular targets of several potent anticancer agents. Thus, inhibitors of these enzymes are potential candidates for anticancer development. Traditionally, Nerita albicilla ha... DNA topoisomerases (topo) I and II are molecular targets of several potent anticancer agents. Thus, inhibitors of these enzymes are potential candidates for anticancer development. Traditionally, Nerita albicilla had been used in Kei Island, Southern Maluku, Indonesia to treat liver disease including cancer. The paper reports on the chemical composition ofNerita albicilla and its topo I inhibitor ofhexane, ethyl acetate and methanol extracts. Topoisomerase-I inhibitor activity was determined using the method reported by TopoGEN. The proximate analysis described that Nerita albicilla dried powder contained 12.45% ± 0.05% moisture; 9.17% ± 0.03% ash; 62.05% ± 0.10% protein; 5.58% ± 0.08% fat; 6.60% ± 0.02% crude fiber and 4.15% ± 0.24% carbohydrate (by difference). Furthermore, the protein consisted of 11 essential amino acids and six non-essential amino acids. It contained significant amount of branched-chain amino acids (BCAA) valine, leucine, isoleucine (a total of 187.8 mg g-1 protein) and lower content of aromatic amino acids phenylalanine, tyrosine and histidine (a total of 111.26 mg .g-1 protein). The protein score was 92.2. The yield of hexane, ethyl acetate and methanol extracts ofNerita albicilla were 2.05% ± 0.05%, 1.56% ± 0.06% and 6.99% ± 0.14%, respectively. All extracts showed topoisomerase-I inhibitor activities. Minimum inhibitory concentration (MIC) of methanol extract was 2.50 ug mL-1. Chemical screening of the extracts showed that they contained steroidal and alkaloid compounds. The investigation revealed that Nerita albicilla contains active compounds that could be potential for nutraceutical or pharmaceutical development. 展开更多
关键词 Nerita albicilla nutritional composition topoisomerase-I inhibitor.
下载PDF
Green Product of Liquid Fuel from Plastic Waste by Pyrolysis at 900 ℃
16
作者 Dianta Mustofa Kamal Fuad Zainuri 《Journal of Energy and Power Engineering》 2015年第1期40-44,共5页
Alternative treatments to convert plastic waste into fuel currently receive great attention from researchers worldwide. The objective of the research is to obtain liquid fuel from pyrolysis of waste plastics that is s... Alternative treatments to convert plastic waste into fuel currently receive great attention from researchers worldwide. The objective of the research is to obtain liquid fuel from pyrolysis of waste plastics that is safe for humans as well as environment, with a heating value and fuel quality meet the standardized compliant. The method used for the research is plastic waste pyrolysis heated at 900 ℃, and the resulting vapor is condensed through a crossflow condenser. The method resulted in a liquid fuel with a calorific value of 46,848 J/g, which is greater than that of plastic waste processing at a temperature of 425 ℃ that is only 41,870 J/g. In addition, the nature of current method for treating plastic waste is considered more secure than that of plastic waste processing at the temperature of 425 ℃. The reason for this is the fact that the percentage of compounds that could potentially be carcinogenic (boric acid and cyclopentanone) is reduced. 展开更多
关键词 Plastic waste FUEL PYROLYSIS green product
下载PDF
Improving Fuel Diesel Efficiency Using Fuel Filter
17
作者 Tatun Hayatun Nufus Dianta Mustofa Kamal Sri Lestari Kusumastuti 《Journal of Energy and Power Engineering》 2016年第6期364-367,共4页
The price of fuel oil continues to rise, decreased supplies oil at the other side, both factors increase the interest of researchers to conduct research related to fuel efficiency. Therefore the aim of this study is t... The price of fuel oil continues to rise, decreased supplies oil at the other side, both factors increase the interest of researchers to conduct research related to fuel efficiency. Therefore the aim of this study is to improve the efficiency fuel of diesel engine using fuel filter. The method used for the research is testing the most efficient fuel filters made of coil wire coil winding 5,000, the three distinguished from the coil core diameter of 44.5, 28.5 and 17.5 mm in diesel engine. The performance test was conducted from 1,100 rpm to 1,700 rpm, the throttle opening of 30%-60%. The first testing was done by creating a constant speed 1,500 rpm and throttle opening varies from 30% to 60%, further testing is done by varying the rpm start from 1,100 rpm to 1,700 rpm to make constant valve 40% and 60%. 展开更多
关键词 Specific fuel consumption CLUSTERING de-clustering throttle.
下载PDF
Simulation and experimentation of Propeller-Savonius turbine tested underwater surface
18
作者 Sri Wuryanti Teguh Sasono +2 位作者 Bambang P.Manunggal Wahyu B.Mursanto Sugianto 《Clean Energy》 EI CSCD 2024年第3期20-33,共14页
Indonesia’s vast maritime territory offers a unique opportunity for harnessing the potential Energy of seawater currents.This study explores the effectiveness of a combined Savonius and propeller-type turbine system.... Indonesia’s vast maritime territory offers a unique opportunity for harnessing the potential Energy of seawater currents.This study explores the effectiveness of a combined Savonius and propeller-type turbine system.The Savonius turbine,known for its efficiency in capturing ocean currents due to its large sweep area,is combined with a propeller-type turbine to enhance rotational speed and power generation.A novel approach is employed to induce turbulence and optimize energy extraction,first channeling water through the propeller turbine and then into the Savonius turbine.A comprehensive investigation is conducted through simulations and experimental tests within a controlled tunnel environment.The study explores the performance of two-bladed and three-bladed Propeller-Savonius configurations at varying inlet water velocities(0.1,0.3,0.6 and 1.0 m/s).The simulation incorporates a turbulence model with 5%intensity and a hydraulic diameter of 0.216 m.Results indicate that the proposed configuration achieves a maximum power output of 2.0293 W with an impressive efficiency of 63.339%in simulation.Concurrently,experimental testing yields a peak efficiency of 61.335%and turbine power of 0.3951 W.The findings demonstrate the feasibility of the combined turbine system and highlight the importance of turbulence in optimizing energy extraction from seawater currents.This research contributes valuable insights into the design and performance of hybrid turbines for harnessing oceanic Energy,emphasizing the potential for sustainable power generation in maritime regions.The methodology and results presented herein offer a foundation for further exploration and refinement of seawater current energy conversion technologies. 展开更多
关键词 hydro-turbine propeller-Savonius renewable energy water
原文传递
Assessing the impact of booster vaccination on diphtheria transmission:Mathematical modeling and risk zone mapping
19
作者 Ilham Saiful Fauzi Nuning Nuraini +4 位作者 Ade Maya Sari Imaniah Bazlina Wardani Delsi Taurustiati Purnama Magdalena Simanullang Bony Wiem Lestari 《Infectious Disease Modelling》 CSCD 2024年第1期245-262,共18页
The COVID-19 pandemic caused significant disruptions in the healthcare system,affecting vaccinations and the management of diphtheria cases.As a consequence of these disruptions,numerous countries have experienced a r... The COVID-19 pandemic caused significant disruptions in the healthcare system,affecting vaccinations and the management of diphtheria cases.As a consequence of these disruptions,numerous countries have experienced a resurgence or an increase in diphtheria cases.West Java province in Indonesia is identified as one of the high-risk areas for diphtheria,experiencing an upward trend in cases from 2021 to 2023.To analyze the situation,we developed an SIR model,which integrated DPT and booster vaccinations to determine the basic reproduction number,an essential parameter for infectious diseases.Through spatial analysis of geo-referenced data,we identified hotspots and explained diffusion in diphtheria case clusters.The calculation of R0 resulted in an R0=1.17,indicating the potential for a diphtheria outbreak in West Java.To control the increasing cases,one possible approach is to raise the booster vaccination coverage from the current 64.84%to 75.15%,as suggested by simulation results.Furthermore,the spatial analysis revealed that hot spot clusters were present in the western,central,and southern regions,posing a high risk not only in densely populated areas but also in rural regions.The diffusion pattern of diphtheria clusters displayed an expansion-contagious pattern.Understanding the rising trend of diphtheria cases and their geographic distribution can offer crucial insights for government and health authorities to manage the number of diphtheria cases and make informed decisions regarding the best prevention and intervention strategies. 展开更多
关键词 DIPHTHERIA VACCINATION Mathematical modeling SIR model Hot spot analysis
原文传递
A new approach of CO_(2)separation by applying rapid expansion of supercritical CO_(2)rich natural gas
20
作者 Saripudin Tutuka Ariadji +2 位作者 Sanggono Adisasmito Leksono Mucharam Doddy Abdassah 《Petroleum Research》 EI 2023年第1期71-76,共6页
The previous methods for CO_(2)separation from CO_(2)rich natural gas led to expensive production costs.This work was implemented to overcome the problems utilizing a new approach economically.The cooling and rapid ex... The previous methods for CO_(2)separation from CO_(2)rich natural gas led to expensive production costs.This work was implemented to overcome the problems utilizing a new approach economically.The cooling and rapid expansion processes were integrated for the CO_(2)separation from CO_(2)rich natural gas on the supercritical condition.The experimental apparatus was newly constructed to perform the experiments,and the results were simulated using a various equation of state.The result reveals that the inlet temperature of supercritical expansion diminished the outlet temperature and the gas condensed easily.The simulation indicated that the 70%CO_(2)in natural gas was condensed easier than 45%CO_(2).We found that the outlet temperature of42C and the vapor fraction of 0.69 was attained at the CO_(2)composition of 70%.Besides,the pressure drop change influences the vapor fraction at various CO_(2)compositions.The vapor fraction under supercritical diminished significantly compared with the nonsupercritical condition.The expansion coefficient determined utilizing the equation of state escalates by the enhancement of expansion inlet temperature based on CO_(2)composition in natural gas.The acid gas equation of state was the perfect equation to estimate the expansion coefficient with the absolute average error of 4.83%.This work suggests that the CO_(2)separation from CO_(2)rich natural gas with the cooling and rapid expansion method promotes the new approach to overcome the disadvantages of previous methods. 展开更多
关键词 Rich natural gas CO_(2)separation SUPERCRITICAL COOLING Rapid expansion
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部