Nadhifa Salsabila | University of Indonesia (original) (raw)
Papers by Nadhifa Salsabila
Journal of Physics: Conference Series
Geometry is important material in mathematics, but some students still find it difficult to learn... more Geometry is important material in mathematics, but some students still find it difficult to learn geometry. The teacher used technology to make it easier for students to learn geometry. The aim of this study is to describe the perception of junior high school students on technology in geometry learning. This type of study is a survey study. The population of study were 100 junior high school students in MTsN 1 Mataram, NTB, Indonesia. The data were taken from 3 to 4 December 2019. The data were collected by questionnaire. Data were analysed using quantitative descriptive methods. The results showed that most students were able to utilize technology in their daily lives. There are 57% of students who have experience learning geometry with technology. There are 67% of students utilizing technological devices for learning geometry and 66% of the devices students often use are smartphones. There are 56% of students who use learning technology such as a learning video. The data also show...
Energy
East Nusa Tenggara (NTT) is a province with low electrification ratio (78.3%) and high number of ... more East Nusa Tenggara (NTT) is a province with low electrification ratio (78.3%) and high number of underdeveloped villages (74.8%), despite its abundant renewable energy resources potential. The objective of this study is to obtain technically-economically feasible village model with integrated renewable energy system for developing productive zone, Prukades-postharvest cocoa processing, in Wewaria, NTT. The methodology used is technoeconomic analysis, in which technical analysis include optimization for hybrid power generation system (HPGS), done by using HOMER Pro. Several financing schemes are proposed to evaluate the economic feasibility. Environmental comparative analysis of mitigated GHG emission is also evaluated. It is found that the HPGS consists of 95 kW photovoltaic, 78 kW wind turbine, and 200 kW diesel generator, equipped with battery storage, and the Prukades system has annual capacity of 250 tons of wet cocoa beans/year with 32.9% yield. Prukades system is economically feasible with all proposed schemes, and potential to increase annual income of cocoa farmers. On the other hand, HPGS is only economically feasible with FS-5 scheme with 100% grant as financial intervention. The economic attractiveness of both systems is relatively higher by using integrated scenario, both owned by the same business entity, resulting in 3 other schemes to be feasible.
A maintenance strategy is an important factor in the production activities of the process industr... more A maintenance strategy is an important factor in the production activities of the process industry. Since the process industry consists of many components, the failure mode is relatively complex. This paper observes one of the petrochemical companies in Indonesia which produces Pythalic Anhydride. The company is able to produce in 20.69 days every month. In reality, during 2017, the company produced 23 days every month on average. Production, known as the calendar day, which cannot achieve the target can affect customer service level. This research focuses on evaluating availability in order to minimize Mean Time to Repair (MTTR). One of the best strategies is to control the spare part inventory policy so that the spare part must be available when an equipment downtime occurs. We will use two modeling techniques to solve the problem: (a) reliability block diagram will be used to model the failure mode and (b) the simulation model will be used to model the entire system, including random variables and variable inter-dependency. After conducting scenario analysis by varying some parameters, the availability increased to 91.8% and average calendar days decreased to 22.64 days per month.
Journal of Physics: Conference Series
Geometry is important material in mathematics, but some students still find it difficult to learn... more Geometry is important material in mathematics, but some students still find it difficult to learn geometry. The teacher used technology to make it easier for students to learn geometry. The aim of this study is to describe the perception of junior high school students on technology in geometry learning. This type of study is a survey study. The population of study were 100 junior high school students in MTsN 1 Mataram, NTB, Indonesia. The data were taken from 3 to 4 December 2019. The data were collected by questionnaire. Data were analysed using quantitative descriptive methods. The results showed that most students were able to utilize technology in their daily lives. There are 57% of students who have experience learning geometry with technology. There are 67% of students utilizing technological devices for learning geometry and 66% of the devices students often use are smartphones. There are 56% of students who use learning technology such as a learning video. The data also show...
Energy
East Nusa Tenggara (NTT) is a province with low electrification ratio (78.3%) and high number of ... more East Nusa Tenggara (NTT) is a province with low electrification ratio (78.3%) and high number of underdeveloped villages (74.8%), despite its abundant renewable energy resources potential. The objective of this study is to obtain technically-economically feasible village model with integrated renewable energy system for developing productive zone, Prukades-postharvest cocoa processing, in Wewaria, NTT. The methodology used is technoeconomic analysis, in which technical analysis include optimization for hybrid power generation system (HPGS), done by using HOMER Pro. Several financing schemes are proposed to evaluate the economic feasibility. Environmental comparative analysis of mitigated GHG emission is also evaluated. It is found that the HPGS consists of 95 kW photovoltaic, 78 kW wind turbine, and 200 kW diesel generator, equipped with battery storage, and the Prukades system has annual capacity of 250 tons of wet cocoa beans/year with 32.9% yield. Prukades system is economically feasible with all proposed schemes, and potential to increase annual income of cocoa farmers. On the other hand, HPGS is only economically feasible with FS-5 scheme with 100% grant as financial intervention. The economic attractiveness of both systems is relatively higher by using integrated scenario, both owned by the same business entity, resulting in 3 other schemes to be feasible.
A maintenance strategy is an important factor in the production activities of the process industr... more A maintenance strategy is an important factor in the production activities of the process industry. Since the process industry consists of many components, the failure mode is relatively complex. This paper observes one of the petrochemical companies in Indonesia which produces Pythalic Anhydride. The company is able to produce in 20.69 days every month. In reality, during 2017, the company produced 23 days every month on average. Production, known as the calendar day, which cannot achieve the target can affect customer service level. This research focuses on evaluating availability in order to minimize Mean Time to Repair (MTTR). One of the best strategies is to control the spare part inventory policy so that the spare part must be available when an equipment downtime occurs. We will use two modeling techniques to solve the problem: (a) reliability block diagram will be used to model the failure mode and (b) the simulation model will be used to model the entire system, including random variables and variable inter-dependency. After conducting scenario analysis by varying some parameters, the availability increased to 91.8% and average calendar days decreased to 22.64 days per month.