bluuebunny/crossref_metadata_2025 huggingface dataset:
Economic valuation of protection and production forests in pekalongan regency
Authors: Harini R. , Yuniantari R. , Ariani R D
Published: March 2021

Regional autonomy authorizes local governments to optimize sources of income, one of which is through natural resources. Pekalongan Regency is a district in Central Java which has the potential of forest resources covering an area of 28,486 Ha including limited protected forests, production forests and limited production forests managed by Perum Perhutani. Forests are renewable natural resources that need to be managed sustainably to enable them to fulfill their (economic, social, environmental sustainability) functions according to sustainable development principles. Considering that at present some people do not have insights into the values of forest resources, especially their intangible benefits, this present study aimed to analyze the total economic value of protection and production forests to inform people about the economic value of forest resources. This study used a descriptive-quantitative method with primary and secondary data sources. The quantitative data processing technique used was the Total Economic Value model supported with the market price method, the travel cost method, and the benefit transfer method. The results of the analysis revealed that the economic value of protection and production forests in Pekalongan Regency is IDR. 232,355,092,970. The indirect use value (41.36%) of the forests indicates that forests have substantial intangible benefits. The total economic value analysis of the forests can be used as a recommendation for local governments and stakeholders in allocating forest resources to keep them in the sustainable development order.
Perception of the community affected by evictions in the bengawan solo river border of surakarta city in 2017
Authors: Ajar S B
Published: March 2021

River Normalization Aims to overcome flood disasters. One of the processes of normalization of bengawan solo is to clean the river border from the settlement. The eviction of settlements in the river border of the Bengawan Solo in the city of Surakarta will lead to positive and negative perceptions for the affected community. This study aims to determine the perceptions of the people affected by evictions in the Bengawan Solo river border of Surakarta city. This research uses descriptive method and research sampling is that the people affected by the eviction of settlements in the Bengawan Solo border include Joysuran Village, Sangkrah Village, Sewu Village, and Semanggi Village in Surakarta City. The results of the study showed that the affected community in Surakarta City gave a positive response to the process of evicting Bengawan Solo river border settlements in the form of approval of evictions with some conditions but the affected people also gave a negative response to the process of compensation for eviction of Bengawan Solo river border settlements in the form of unwillingness to be evicted before an agreement in compensation took place
The socio-economic impact of relocation policy to the communities affected by the mount sinabung eruption: a preliminary study
Authors: Novira N , Maxriz J , Restu  , Elfayetti  , Astuti A J D
Published: March 2021

Mount Sinabung has long been dormant. Since 2010, the great giant has woken up from the big sleep and has periodically been erupting ever since. The series of eruption resulted in catastrophic damage to many of the surrounding area, resulted in inhabitable villages. Many of the relocated inhabitants returned to their home village for one or more reasons while some others never moved at all. This indicated that there are some problems in the relocation policy. As a part of the research project ‘The Socio-Economic Impact of Relocation Policy to the Communities Affected by Mount Sinabung Eruption’, this study aims to explore the underlying factors of the returning relocated inhabitants from the relocation area to their home village and those who chose to stay in the andger area. The results demonstrated that the loss of source of income and the lack of alternative livelihood strategy are the main reasons to leave the relocation area. The secondary reason is the difficult access to children’s education and the problematic policy. From the results we learned that housing quality and the supporting facility are not the only factor that needs to be considered in the relocation plan.
Key geographical features on malaysia’s land tax system: a comparison study in negeri sembilan, malaysia
Authors: Adnan M Z , Suratman R , Samsudin S
Published: March 2021

Land tax or quit rent constitutes a form of tax levied against all alienated land in Malaysia. According to Federal Constitution, land is a state matter which mean it is the right and responsibility of the state government to administer the land in the jurisdiction. Though mandated, state governments also have responsible to assess and collect land tax. The amount of land tax on the ownership of unimproved or improved land, generally varies from state to state and within each state it also varies according to geographical physical features. In view, this paper investigates the primary geographical features that influencing the land tax and compare the differences rate in the case study area. This study using desk research approach from secondary resources. The result shows that the land tax rate primarily subject to land classification, locality and category of land use. Generally, all states have different rates for agricultural, building or industrial land based on the State Land Rules. Under each category of land use such as building, there are again different rates depending on whether the land is used for commercial or residential. Further, the evidence indicates that not all land used for such usage i.e. residential purpose has the same rate, depends on whether the land is classified as a town, village or country land. It also depends on the district where the parcel is located. The findings provide strong support for future land legislation policy reforms, along with other geographical features, in local land taxation system.
Spatial dynamic of land surface temperature in ciliwung watershed
Authors: Aditya M R , Tambunan M P , Purwadhi F S H
Published: March 2021

Land surface temperature (LST) is one of critical element in urban climatology study, especially on urban heat island (UHI) mitigation and water balance. Urbanization in Ciliwung watershed continuously erodes open areas and considerably significant affect the surface temperature within watershed area. Therefore, the purpose of the study is to explore the potential contribution of land surface rising between elevations, vegetation and built-up index. Landsat 8/OLI satellite images use to derive LST, normalize differences vegetation index (NDVI) and normalized differences built-up index (NDBI) in study area on 2014 and 2018. Furthermore, elevation derive from DEMNAS raster provide by Geospatial Information Agency (BIG). In summary, there were LST increases from means temperature from 28.52 Celsius (2014) to 29.10 Celsius (2018) along with land cover changes (LCC). Meanwhile, LST spatial distribution is very closely related to the distribution of NDVI and NDBI. Statistical test results show high correlation (R-squared = 0.89 - 0.91) between LST, elevation, NDVI and NDVI. This indicates elevation, NDVI and NDBI factor play a significant role in LST dynamics.
Hydrometeorological hazard prediction in the kuto bodri river region central java based on normalized difference vegetation index (ndvi) analysis
Authors: Basuki Y , Widjonarko
Published: March 2021

The objective of this paper is to predict drought as a hydrometeorological hazard to anticipate the lack of water in Kuto Bodri River Region. The method based on Normalized Difference Vegetation Index (NDVI) analysis. Drought assessment based on the assumption of photosynthetic. If photosynthesis goes well, it indicates that enough water is available to support the process. The data is using Landsat 8 image from March to October 2018. The results show that the potential of drought occurs in the Kuto Bodri River Area in the September-April period. The NDVI value in the period shows a low number, the pattern of distribution of NDVI with a low value is quite even and even in the upstream region which in fact is a forest area NDVI value shows a minus number, meaning photosynthesis does not run well and indicates the availability of water is minimal. The potential drought threat in the Kuto Bodri WS began in June 2018 to October 2018 and occur in the downstream area, especially in the type of paddy fields. Based on this result it is necesary to make policy to anticipate and overcome this hazard such as sosialization in farmer community.
Multitemporal landsat image utilization for spatial prediction of built up area in tasikmalaya city, indonesia
Authors: Ridwana R , Sugandi D , Arrasyid R , Himayah S , Pamungkas T D
Published: March 2021

Changes in built up area which are increasingly rapid consequence of the latest data requirements for urban planning. On the other side the process of expansion of built up area without control can impact the destruction of lands that have ecological functions so that they have an effect on the onset of social and environmental disasters. Of the many cities in Indonesia, the City of Tasikmalaya is one of the most significant cities that develops the built-up area. Effective technology that can be used to predict the development of built up area in the City of Tasikmalaya is to utilize multitemporal landsat imagery. This study aims are 1) Identify changes in built up area in Tasikmalaya City and its surroundings based on multitemporal landsat imagery, 2) Predict the development of built up area in Tasikmalaya City. The research method uses remote sensing technology, multitemporal recording landsat imagery in 2002 and 2019, through landuse change modeler modeling. The results of this study indicate an increase in built up area from 2002 to 2019, predicted results of the development land built up in 2034 produce a probability of expansion 0.229 with the direction development from northeast to southwest.
The impacts of mangrove ecotourism management on the socio-economic conditions of people in kulonprogo regency
Authors: Fistiningrum W , Harini R
Published: March 2021

Jangkaran Village is one of areas in the Special Region of Yogyakarta that has mangrove forests. Mangrove forests have unique characteristics and values of natural beauty so that they have the potential to be managed into mangrove ecotourism, particularly in Pasir Mendit and Pasir Kadilangu hamlets. Since mangrove ecotourism management also involves the surrounding communities the purpose of this present study was to assess the extent of community participation and mangrove ecotourism impacts on the socio-economic conditions of the surrounding communities. The study was conducted with survey methods using questionnaire instruments to collect the data. The research subjects were people who are involved or not involved in mangrove ecotourism management. The number of respondents sampled with quota sampling method was 40. The data were processed into frequency tables from scoring with Likert scale to determine the extent of community participation. The data were quantitative-descriptively analyzed with the Spearman Ranking Test to determine the relationship of internal factors with the level of community participation and the T-test to see the differences in the community conditions before and after the existence of the mangrove ecotourism and the differences between those people who are involved and not involved in the mangrove ecotourism management. The results showed that the levels of community participation in mangrove ecotourism management was moderate during the planning stage (3.05), very high during implementation and benefit taking (4.24 and 4.60, respectively), and high during evaluation (3.56); the impacts of mangrove forest ecotourism management to the community condition in the forms of additional income generating activities related to mangrove forests and social interaction in the form of voluntary works before and after the existence of mangrove ecotourism were similar, i.e. 47.5%; there was binding regulation that was moderate adhered (52.5% ) by the community, and; there were social conflicts (67.5%). The T- test statistics showed differences in the community incomes before and after the existence of mangrove tourism and between those who are involved and not involved in the mangrove ecotourism management.
The integration of local creativity-based tourism by the LED approach
Authors: Rahmafitria F , Purboyo H
Published: March 2021

Regional development model with top down approach oftentimes became uneffective in gaining local welfare and equity. Then, Local Economic Development (LED) become the way, with focus on local empowerment in stimulating local industries and economic growth. This paper discuss the idea of LED based on local creative communities as a basis in developing tourism in regional context. The implementation of this approach will run effectively if tourism development is integrated on the regional strategies. The study conducted with comparing secondary data of tourism and regional development achievement in West Nusa Tenggara (NTB). The result shows that the high rate of tourism investment is not significantly correlating with the increasing of local welfare. Instead of that, the number of poor communities and the unoptimistic perceived on jobs availability is increased. The concept of local creativity tourism is expected to encourage local economic development through local resources empowerment.
Sustainable tourism issues in local communities in ijen-baluran
Authors: Purnomo A , Syahbuddin I H , Glenn P
Published: March 2021

Tourism does provide many economic benefits that trigger an increase in the quality of the social environment and the strengthening of cultural values as a commodity. However, these benefits are not always consistent with sustainable management. In this article, the research gap focused on how local communities in managing sustainable tourism. In-depth surveys and interviews conducted in three local communities who manage travel in the National Tourism Strategic Area (KSPN) Ijen Baluran, which includes Situbondo, Banyuwangi, and Bondowoso. The analysis showed that the ability of communities in managing sustainable tourism relies heavily on the experience of interacting with tourists outside the area, government support and partner network. Interaction with tourists outside the area will provide a social exchange about the expectations of travelers or travel trend is growing. Interaction and social exchange to be a catalyst in accelerating the achievement of sustainable tourism management.
The characteristics of ethnics people at the banks of musi river in palembang
Authors: Putri M K , Nuranisa N , Mei E T W , Giyarsih S R , Sukmaniar S , Saputra W
Published: March 2021

The objective of this research is to observe the ethnics people at the banks of Musi River (River Side) Palembang. The writer used qualitative method. The respondents of this research is 397 people living at the River Side of Musi in Palembang. The technique of data colletion in this research is interviewing and site observation. Then, the data is qualitatively learnt and selected using certain stage i.e. data reduction, data presentation, drawing conclusion, and verification. The results of this research is that the ethnics of people living at the banks of Musi River consist of Malaya (Melayu), Arab, Java, and Sulawesi. The dominant people living at the River Side of Musi is from Malaya. The reasons why they live there (River Side of Musi) is that the majority is based on their parents’heritage and heredity. Another reason is the cost of or hiring living houses is relatively cheap. Their levels of education are relatively low : and consequently, they are unable to live in other places.
Gentrification analysis of the social condition of the community in sarangan lake tourism area
Authors: Gumilang C , Yusup Y , Wijayanti P
Published: March 2021

Gentrification is understood as a change in the socio-economic status of an area that has been more inhabited by low-income people, then replaced by people who are better able to develop activities and investments in the area. This research is a qualitative exploratory study of the inductive approach to reviewing the adaptation pattern of the indigenous peoples in the face of the gentrification process that occurred in the region amid the insistent population of migrants More capable. The study also saw how the indigenous response to migrants and the changes occurred. The results showed that the locals were aware that the land they had had economic value and strategic functions. They adapt to capturing business opportunities to improve Social-Ekonomi status and adapt to the developments that occur. In general, indigenous peoples understand the positive and negative impacts of the surrounding changes as they are more capable of migrants and physical transformation into a more developed environment. This research indicates that indigenous peoples are trying to respond wisely to these changes.
Adaptation of indigenous communities in kampung cireundeu to the environment in maintaining local wisdom
Authors: Shalihah S , Sugandi D , Somantri L
Published: March 2021

This research aims to find out the adaptation of Cireundeu community to its environment and the efforts of the Cireundeu indigenous people to maintain local wisdom, traditional leaders and elders, data collection techniques used by participant observation, in-depth interview, and documentation. Data analysis techniques using qualitative-verification data analysis. The result suggests that 1). In adaptation to the environment, Cireundeu people understand very well that the conditions of the land they live in are not suitable for planting rice, so they choose to plant cassava. 2). Efforts to maintain local wisdom are assured if they continue to consume rice, then one day will experience hunger because the number of people who continue to grow and the availability of agricultural land is also small due to the establishment of residential areas, so they look for the main types of rice, namely (rice cassava) which will support their food security and maintain natural fertiliser is good for the type of cassava.
Sundanese local wisdom in ngebakeun gamelan embah bandong ceremony on bumi lait lebakwangi area of arjasari sub-district in bandung regency
Authors: Sutarman U , Mulayan A , Saripudin D , Sjamsudin H
Published: March 2021

Bandung Regency majority lived by Sundanese, is one of the regencies in West Java Province that has a variety of local wisdom. One of them is the local wisdom in the Lebakwangi area of Arjasari sub-district, which is the ngebakeun (bathing) ceremony that held every year on the 12th of Mulud. One of the activities is bathing kabuyutan gamelan instruments called Gamelan Embah Bandong. From the bathing (ngebakeun) activities and Gamelan Embah Bandong performance which was held at Bumi Alit (small house), Kabuyutan contains values such as friendship and togetherness. The purpose of this research is to find out and study in depth the activities and local wisdom in the Lebakwangi area. The method used in this research is descriptive in the qualitative form. According to the type of data needed, which is qualitative data then the data collection techniques is by using open interview techniques, observation, documentation studies and literature studies. As an implication of this study, among others, as recommendations for more in-depth research in the future, as well as recommendations to the government at both the District and Sub-district Bandung levels in an effort to preserve Sundanese historical sites and local wisdom that develops in the community.
The analysis of palm oil plantation impact on the social geographic conditions in Kapuas sub-district, Sanggau district
Authors: Rahayu S , Santoso S , Wijayanti P
Published: March 2021

The establishment of palm oil plantation in Sanggau is started in 1979. The establishment utilizes the land of Dayak indigenous people in the form of customary rights and managed lands that have been cultivated for generations. Based on the data of 2005, the area of palm oil plantation in Sanggau District is up to 131,148.64 hectares, consisting of large state-owned companies covering 20,512.60 hectares, national private companies 30,453.40 hectares, and foreign private companies 21,999.30 hectares. While the area of palm oil plantation of farmers is 77, 383.30 hectares. The entry of investors in the plantation business area will become a stimulus for the establishment of palm oil factories and job opportunities for local communities and immigrants. The research aims at determining the impact of palm oil plantation on the social geographic conditions in Kapuas, Sanggau. This is qualitative descriptive research. Purposive sampling is employed as the sampling technique. In collecting data, the researchers utilize interviews and questionnaires. Descriptive analysis is employed as a data analysis technique. The results of this study indicate that there is a significant change in the social geographic condition of the local and immigrant communities who stay at Kapuas, Sanggau.
Status and challenges of water governance in facing the water crisis disaster in blora regency, indonesia
Authors: Maryati S , Febriani Y T
Published: March 2021

The water crisis is a problem faced by many cities in the world. The water crisis is a disaster. The condition of the water crisis is further aggravated by climate change. One important factor to overcome the water crisis is water governance. The purpose of this study is to assess the status of water governance to overcome the water crisis. This study used Blora Regency as a case study. Blora Regency is one of the districts in Indonesia which experiences a water crisis every year. The water crisis always occurs in the dry season. In addition to seasonal problems, another problem that causes the water crisis is the uneven distribution of water sources, topographic conditions, access to infrastructure, and seasonal variation. This study uses a governance capacity indicator approach. Criteria to assess government capacity consist of planning, implementation, and monitoring and evaluation. The data was collected from interview with stakeholders and secondary sources. Most of the sub indicators have not been fulfilled. Policies, strategies, programs, and activities have not been derived from the causes of the water crisis, are less innovative, less based on the river basin approach, and have not involved the participation of many parties, and have not been supported by adequate funding. Finally Indicator monitoring and evaluation is not yet an outcome based indicator.
Personalized Gait Treatment Using Passive Controllable Ankle Foot Orthosis
Authors: Abdul Rahman Mohd Azizi , Adiputra Dimas
Published: March 2021

Ankle Foot Orthosis (AFO) is usually prescribed for gait treatment. Low cost, easy to fabricate, safe, long term usage, and personalized AFO is demanded to facilitate and accelerate the prescription process, which is iterative, individualized, and collaborative. Passive Controllable AFO (PICAFO) was developed to fulfil the demand, consisting of several research works, such as the gait detection method, smart actuator design, and controller development. Two gait detection methods had been considered. Firstly, the system utilized the Electromyography (EMG) biosignal to detect the stance and swing phase. Secondly, hybrid Magnetorheological Elastomer (MRE) is used to detect four gait phases based on foot contact. The smart actuator, a small scale Magnetorheological (MR) brake, had been constructed, which generated 2.1 Nm maximum damping stiffness to partially support the ankle stiffness. The controller is essential because controlling the damping stiffness accordingly to the current gait ensures positive assistance. The latest version of the PICAFO controller utilized ankle velocity reference to control the MR brake stiffness, which can be estimated based on the user’s walking speed and body mass index. The presented research works show that achieving personalized gait treatment using the PICAFO system is possible.
Sustainable Energy Storage Management for a Power Plant-Transmission Station System with Hybrid Power Generation and Stochastic Electricity Demand
Authors: Jauhari W A , Pujawan I N , Suef M
Published: March 2021

This paper proposes an energy storage management for electrical energy supply chain system (EESCS) involving a power plant and a transmission station under carbon emission investigation. The transmission station faces stochastic electricity demand from household and uses a continuous review policy to control electrical energy storage. The power plant has two power generations, namely green power generation and regular power generation. The green power generation is cleaner than the regular one, thus it generates less emissions. Although the green power generation is more environmentally, however, its electricity production cost is more expensive than the regular one. A carbon tax is implemented in the investigated system to lessen the amount of emissions coming from electricity production. An efficient algorithm is developed to solve the problem and a numerical example is presented to show the applicability of the model and to explore the behaviour of the model.
A Cut-off Grade Optimization Model in Multi Product Open Pit Mining Considering Reclamation and Valuable Waste Materials
Authors: Novitasari R , Rosyidi C N , Aisyati A
Published: March 2021

The common problem found in the mining company is how to determine the cut-off grade for the classification of ore and waste. The cut-off grade will greatly affect the revenues and costs of the mining companies. In this study, we develop cut-off grade optimization model by considering multi product and environmental factor such as reclamation and revaluing of waste materials. Multi product was chosen because most of the mining industry not only produce one type of mineral products. The main goal of this study is to develop a cut-off grade model to maximize the net present value (NPV). To illustrate the application of the model, the numerical example is given for mining case using the available data of Golgohar Iron Mine in Iran which produced three types of iron products, such as concentrated, sizing, and pellet.
Optimization Model for Determining Order Quantity for Growing Item Considering Incremental Discount and Imperfect Quality
Authors: Luluah L , Rosyidi C N , Aisyati A
Published: March 2021

This research develops an optimization model of order quantities for growing items by considering incremental discounts and imperfect quality. For growing items, the assumption that inventory weights that always fixed cannot be applied. The supply system has grown so that the weight of the inventory has increased over a certain period. The proposed inventory system has two periods namely growth and consumption period. Suppliers offer incremental discounts for certain purchases. In this research also considered the existence of imperfect quality, where for newborn items purchased at the beginning of each cycle found items with poor quality and death. During the growth period, not all items survive until the end of the period, therefore also considering the probability density function of survival and death of growing items. The proposed inventory system is maximization profit, with total profits being an objective function, and cycle times and order quantities as decision variables. Costs involved include purchased cost by considering by incremental discounts, setup costs, holding costs, and disposal costs. Application and model validation is demonstrated by numerical examples in the poultry industry. The model developed in this study can be used as a suggestion for companies to make purchasing decisions.
Mini Review on Eddy Current Brakes Parameter
Authors: Putra M R A , Nizam M , Tjahjana D D D P , Prabowo A R
Published: March 2021

The need for braking systems has increased. The widely used braking system is a friction brake. The use of friction brakes has a problem in maintenance intervals and the risk of failure due to heat generation. Research and the development of the braking system have carried out. Eddy Current Brake (ECB) is an alternative braking system. ECB is braking that uses eddy currents as a source of braking force. Many parameters need to consider in implementing the ECB. There have been many studies on the working parameters of the ECB. However, the previous research has researched the effects of parameters by make experiments or mathematical models. This article provides an analysis of the recent research about the ECB performance parameters. From the review of the previous study, it conducted that better performance of ECB is affected by the density of the use of magnetic flux.
A Numerical Ventilation Problem on Fridsma Hull Form Using an Overset Grid System
Authors: Samuel  , Kim D J , Fathuddiin A , Zakki A F
Published: March 2021

Numerical ventilation problem (NPV) is a problem that often occurs during the numerical simulations process. This problem mostly occurs when the vessel has a high Froude Number, causing inaccurate ship resistance predictions. Numerical ventilation can be considered as one of the major sources of error in numerical simulations that require further analysis. The present paper aims to validate a numerical resistance prediction using Fridsma’s hull form. An overset grid system is implemented in this study to solve using the Volume of Fluid method. The method for improving the accuracy of ship resistance prediction are refinement method, visualization method, and phase replacement method. In this paper, the RANS equation is used to describe the turbulence model using k-ε. On most occasions, the Volume of Fluid model uses multiphase Euler flow, assuming air and water as a phase. This research concludes that mesh refinement method is able to solve numerical ventilation problem with such a good result.
Experimental Performance of A Rotary Desiccant Wheel Without Honeycomb Matrix Structure: A Preliminary Study
Authors: Hanifah U , Karim M A , Haryanto A , Alfiyah R , Taufan A
Published: March 2021

Experimental investigation of a rotary desiccant wheel is presented in this study. The rotary desiccant wheel without honeycomb matrix structure is tested where silica gel is used as the desiccant material. The dehumidification experiment shows the humidity ratio decreased from 0.0205 kg/kg to 0.0182 kg/kg. Due to it has the potential to be a drying machine, an initial drying experiment was also carried out to see the performance of this machine. The drying process shows the machine can reduce the moisture content of the noodle product from 33.86% to 9.95% in 17 hours. Results show that thermal, regeneration, and dehumidification effectiveness is up to 24%, 14% and 11%, respectively.
Recent Progress of Fused Deposition Modeling (FDM) 3D Printing: Constructions, Parameters and Processings
Authors: Prayitno G , Imaduddin F , Ubaidillah  , Arifin Z
Published: March 2021

Fused Deposition Modeling (FDM) is the most widely used 3D printing technique. The use and development of FDM cover various fields such as automotive, airplane, to biomedical. Many studies have been conducted to study the effect of various printing parameters and post-processing treatment on the performance of printing results with FDM. This literature study aims to compile and summarize the latest studies related to the effect of FDM process parameters and post-processing treatment as well as prospects and challenges. The review found that the combination of several synchronized parameter processes can produce parts that are printed better because several parameters are interrelated and can complement to each other. In addition, the quality of FDM printing results is generally found to be better with post-processing treatment although it requires more effort that might not always be feasible for some applications.
Magnetorheological Fluid Yield Stress Prediction Using Particle Swarm Optimization at Low and High Shear Rate Region
Authors: Bahiudin I , Imaduddin F , Mazlan S A , Saphiai M I , Ismail A A
Published: March 2021

Yield stress is an important parameter to measure the performance of a magnetorheological (MR) fluid. The parameter can be obtained by fitting a flow curve consisting of a shear rate-shear stress dataset to a Bingham plastic equation. However, the dataset selection is usually determined by trial and error by selecting the data either at a low or high shear rate region due to there is no standardized selection method. Therefore, this paper attempts to develop a platform to predict the yield stress automatically using particle swarm optimization (PSO). The PSO objective function is inspired by the Biplastic Bingham model. The results have shown that the prediction has shown a good agreement when fitting to the experimental data. Furthermore, the obtained yield stress values at high and low shear rate regions also were discussed from the point of view of the difference and possible effect if the wrong variables are chosen. The evaluations have shown that the gap between the yield stress at low and high regions can be relatively high, which is about more than 10 kPa. The wrong selection of the yield stress at an MR device possibly bring inaccuracy performance prediction/design, especially at high magnetic field value.
Design and Simulation of Single-Input Multi-Output (SIMO) Flyback Converter Using PI Controller for Emergency Power Supply
Authors: Saputri F C , Efendi M Z , Murdianto F D
Published: March 2021

The electricity problems in some regions are different, it can be caused by various things e.g power outages and lack of electricity availability. Whereas the need for electrical energy is increasing as human needs increase. The importance of electricity supply for electronic equipment during disaster or emergency condition forces the electricity needs to be fulfilled and supplied continuously. An emergency power supply is commonly used to solve these problems. However, most of the emergency power supply is only intended for single-input single-output needs. This paper refers to a single-input multi-output flyback converter as an emergency power supply that can provide a multi-output system that has two different output voltage levels, which is specified for charging notebook and cell phone using a PI controller as a voltage regulator. Based on the simulation result, the system can obtain the desired output voltage (19 V and 9.5 V) and also can reach the steady-state response in 0.017 s.
Electromyography (EMG) and Hand Gripping Force During Standing and Sitting
Authors: Mahadi M , Nazmi N , Bani N A , Rahman S A S A , Noor N M , Zainuddin S Z A J
Published: March 2021

Musculoskeletal disorders reduced the motion and strength of upper limb muscle, especially when doing a task repeatedly. Evaluation of upper limb muscle strength has been commonly conducted using hand grip strength measurement. Previous studies had explored Electromyography (EMG) and hand grip strength but when studies related body postures, only hand grip strength method was considered. However, previous studies involved the effect of body postures on upper limb muscle strength only focused on hand grip strength method, not EMG. The aim of this study is to investigate the effect of EMG time domain during standing and sitting while gripping in order to identify the postures that are riskier for musculoskeletal injuries. Three feature extraction namely root mean square (RMS), mean absolute variance (MAV), and variance (VAR) were used to represent the EMG. Based on the result, the responses of 0.118 μV, 0.0613 μV, and 0.0139 μV were recorded at sitting position while 0.1455 μV, 0.0843 μV, and 0.0148 μV were recorded at standing position, for respective feature extractions. It shows that the response value of EMG changed for different body postures. To conclude, the body posture is crucial when conducting the upper limb studies for both hand grip strength measurement and EMG.
Design and Analysis Performance Solar Power Plant 15 kW By Maximizing Final Yield and Performance Ratio In Small-Medium Office
Authors: Apribowo C H B , Nizam M , Pramono S , Maghfiroh H , Hakim K
Published: March 2021

The 15 kW solar power plant (PLTS) is a new certain in the application of small-medium solar energy usage, especially for the campus environment in Indonesia which can support and become proof of realization green campus program. The existence of 15 kW PLTS become an attention to do advanced analysis in order that production of the specific electric energy or final yield (YF) and performance ratio (PR) from a PLTS can be monitored based on installation location. The value of YF and PR can be used as reference to do identification, trouble operation analysis, and developing of a PLTS. The optimum value of YF and PR on the 15 kW PLTS resulted by doing simulation from a simulator software, which the value resulted from location and configuration of the system installation without watch shading factor. And then the simulation value compared with electric energy real production result on this 15 kW PLTS. The 15 kW PLTS divided be two lines, that are 5 kW and 10 kW line. From simulation result, showed that in the 5 kW line have value of optimum production is 5264.8 kWh with PR 83,1% and in the 10 kW line have value of optimum production is 7687.2 kWh with PR 83.12%. Real production in line 5 kW is 1326.9 kWh with difference 74.79% with simulation and in line 10 kW is 1643.3 kWh with difference 78.62% with simulation. The shading and existing disturbances resulted in a decrease in electrical energy production and performance in the line 5 kW is YF 0.91 hours/day with CF 2.79% and in the line 10 kW is YF 3.07 hours/day with CF 11.73%.
Using Data Mining Techniques to Predict Students’ Performance. a Review
Authors: Lynn N D , Emanuel A W R
Published: March 2021

Predicting students’ performance is an essential activity towards the success of the world’s education sector. However, the action continues to present itself as a challenging task due to the existing large data amounts in educational databases. On the other hand, some Institutions lack systems that are capable of analyzing and monitoring students’ performance. This problem could be partially due to a lack of awareness about the importance of predicting students’ performance. In addition to that, the existing studies on performance prediction methods are still inadequate in identifying and convincing educators with the most suitable method for predicting students’ performance. This review explores the commonly used data mining techniques to predict students’ performance in previous studies to find out the most suitable technology that can be trusted with predicting students’ performance. The result of the study showed that the decision trees algorithm is the best classification technique that gives trusted and accurate results when it comes to student performance prediction. Predicting students’ performance helps in monitoring the students’ progress, both pass and fail, and therefore provides a gap for early interventions and decision making by educators. This opportunity dramatically helps in promoting the education sector by raising the academic standards of educational Institutions.
An Optimum Design and Economic Analysis of Renewable PV-Standalone Power Plant for Electric Vehicle Charging Station in Indonesia
Authors: Apribowo C H B , Nizam M , Anwar M , Arifin Z , Tjahjana D D D P , Iftadi I , Inayati  , Ramelan A , Falich M N
Published: March 2021

Electric vehicles have recently been increasing in popularity and market demand which can be used as a key indicator for the future due to climate change and global warming so that CO2 emission reductions are needed. In addition to environmental factors which are the main motivation for the increase in electric vehicles, this type of transportation reduces dependence on fossil fuels and contributes a lot to energy independence. The increasing popularity of electric vehicles requires a country to build a charging station for the community in the future, including Indonesia. For that reason, this study was made to obtain the most optimal PV-standalone design as a charging station with the economic analysis. Semarang city is the location of choice because of the potential for strategic resources and is one of the cities with the highest number of vehicles. The result is that 23.2kW PV, 9kW converter, and 40kWh battery are the most optimal for charging stations in the city of Semarang with 10 electric cars every day, with a total daily load of 88kWh/day.
Application of Lean Project Management Method in Environmental Drainage Development Case Study: x Area Bekasi City
Authors: Maulana S , Ariyanti F D
Published: March 2021

Drainage systems are infrastructures for runoff water management and flooding in the settlements area. Many factors cause the drainage system not to function properly. This study was conducted on the implementation of an urban drainage system project in the X Area of Bekasi City using the Lean Project Management Method to analyse waste from resources, analyse risks and manage variations on costs, time, and human resources. The results of the analysis of risk responses that are important to note are the lack of supervision of the implementation of OHS in the field, lack of coordination and outreach to the residents, working hours of irregular (ineffective) use of the equipment, and unskilled labour. Based on the estimated cost of the construction project of the urban drainage system in the X Area of Bekasi City, there has been a change of actual cost (addendum contract) of 8.9% greater than the planning cost (initial contract). Based on the calculation, total savings with the CCPM method in the construction of the urban drainage system in the X area of Bekasi City are Rp. 2,894,136,099.
Scrap Metal Reduction as the Effect of Combustor Upgrade in GTG 1.3 PLTGU Muara Karang
Authors: Leilan F , Revina T , Dimassetya I , Rahmanissa A
Published: March 2021

Metal as one of the most common used materials in industry, needs a proper management for it will not contaminate the land. Metal waste, or also called scrap metals, is disposed in a scrap yard. To prevent the accumulation of scrap metals in the scrap yard area, reducing the generation of it is important. Especially when the auction procedure for scrap metals takes a long time. PLTGU Muara Karang had upgraded GTG 1.3 to Advanced Extendor Combustion System in October 2016 to improve its operational excellence. The impacts of upgrading gas turbine to Advanced Extendor Combustion System, are not only for better efficiency in performance, but also extending the maintenance interval up to 32000 hours. By extending the maintenance interval, combustion inspection, which is usually performed every 8000 hours, can be dismissed. The total maintenance duration needed also reduced from 120 days to 66 days on 8 years period. This leads to reducing metal waste generated during maintenance. By calculating the spare parts that required to be replaced in one combustion inspection, the metal waste reduction potential is 2.26 ton. For 8 years period, the combustor upgrade help to reduce metal waste generation about 75.02%.
Emission dispersion modelling of Gresik power plant using Gaussian analysis to evaluate environmental impacts in receptor point
Authors: Damara D Y , Dermawan M D
Published: March 2021

Air pollution is one of the impacts that must be concerned by Gresik Power Plant. The presence or absence of pollution can be seen in the ambient air quality around the plant location which is routinely monitored every six months. However, the monitoring data is not representative because there is no daily data conducted. Therefore, emission dispersion modeling can be carried out to obtain ambient air conditions around the plant site. In this research, the modeling is carried out using Gaussian Analysis for the HRSG chimney 3.1 and it can be seen that the area around the power plant and Pulopancikan village are significantly affected. This is indicated by the presence of a red zone in the results of the modeling and the concentration of NO2 pollutants can reach 892.65 µg/m3 exceeding the government standard (150 µg/m3). However, the validation of the model shows significant gap due to some circumstances such as meteorology condition, vehicles pollution, and human activities. In consequence, such a modeling can be developed further. For instance, the study needs to forecast emission dispersion of all active chimneys on the site in order to capture environmental condition and more concern to meteorology condition and other pollution sources.
Failure Analysis in Lacing Wire Of Last Stage Low Pressure Steam Turbine Blade
Authors: Kongkong A M , Setiawan H , Miftahul J , Laksana A R , Djunaedi I , Suwarno
Published: March 2021

The present paper studies a root cause of failure analysis of lacing wire used in the last stage blade of low pressure (LP) steam turbine. The lacing wire is made of Stainless Steel Grade 17-4 PH with a diameter of 1.4 mm. The failure occurred after the unit had been operated for 4 years. The fault occurred several times during the operation periods. The failure location is near the tack weld which has functions as a stopper between the lacing wire and the stub. Macro fractography, light optical microscope and scanning electron microscope were used to examine the fracture surface and microstructure closed to the failures. The cyclic stress was evaluate using harmonic analysis simulation using FEA (finite element analysis) Ansys 2019 R2. The benchmark that is indication of fatigue failure was clearly visible. It is concluded that the failure mechanism is fatigue failure with crack initiation. Improper maintenance procedures especially welding procedures trigger an initial crack and then the initial crack gets a concentrated cyclic load causing lacing wire broken.
Numerical Study to Improve Fluid Flow Patterns in HRSG by using a Turning Vane and a Combination of using a Turning Vane with Transition Zone Geometry Modification
Authors: Yuwono E A , Widodo W A
Published: March 2021

Since operated from 1995 until 2018, the total steam production of HRSG 1.1 has decreased by 6.34 % and exhaust gas outlet temperature increased by 40.86 °C. From previous studies on HRSG it can be assumed that flue gas flows at HRSG 1.1 has nonuniform velocity and temperature distribution. This research is carried out by modeling and simulating HRSG as porous media using Computational Fluid Dynamic (CFD) software. The simulation will be carried out on a 3D model with the steady-state condition, use energy model, a heat exchanger (HE) model, and standard k-ε as a turbulence viscous model. Energy absorption in HE will be modeled by an ungroup macro model with fixed inlet temperature and NTU model. Simulations in HRSG are implemented at a corner angle of 6 degrees (original), adding a turning vane on the inlet duct and combination adding a turning vane on inlet duct with 12 degrees corner angle on transition zone. Model validation was accomplished comparing simulation data to power plant data. The result shows adding a corner angle in the transition zone and installing a turning vane in the curve bend minimizes secondary flow in the transition zone. Heat absorption increases 0.008% and exhaust gas outlet temperature decrease 0.04% compared to the existing model.