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Renewable energy is the future energy for the substitution of the depleting fossil fuels. In Indonesia, biomass is one of promising renewable energy due to its abundant availability. Biomass can be converted into energy by thermochemical process, such as pyrolysis. In the implementation, pyrolysis can be applied in household cookstove, called pyrolytic stove. Pyrolytic stove will be proposed for people still cooking over an open biomass fire. This paper studied the pyrolysis of Indonesian teak using household pyrolytic stove. The effect of outer air holes on the performance of household pyrolytic stove was investigated. The increasing of cross section area of outer air holes effected on the higher of biomass combustion releasing energy for pyrolysis and cooking. Furthermore, the optimum outer air holes condition in the stove was fully open with the minimum of char product and the maximum of energy recovered for cooking. [ABSTRACT FROM AUTHOR]

A slope assessment to predict the probability of landslide occurrence and the safety factor of landslide at E9 building, Home Economics Department, Universitas Negeri Semarang was conducted to obtain a safety factor index of slope and structures in study area. A rupture of soil surface appeared in some parts of the study area. It indicated an initial destruction of structure and infrastructure. Differential settlements occurred in north side of building. Therefore, a downward movement of soil, rock mass and debris to the slope direction was identified as an initial hypotheses. The influence of season was analyzed in this paper. A combination of LHZ method and numerical analysis by Plaxis version 9.2 was utilized for the predicted behavior of soil movement and the safety factor. The results of analysis revealed that the safety factor in the wet season reached 1.0635 and in the dry season reached 1.075. From this results, it can be concluded that the influence of season parameter of the season did not affect for the possibility of landslide in this area. [ABSTRACT FROM AUTHOR]

Nyamuk Island in Karimunjawa District is one of the regions in Java that has no access to electricity grid. The electricity in Nyamuk Island relies on diesel engine which is managed by local government and only operated for 6 hours per day. It occurs as a consequence of high fuel cost. A study on smart micro grid system based on renewable energy was conducted in Combustion Engine and Propulsion System Laboratory of Institut Teknologi Bandung by using 1 kWp solar panels and a 3 kW bio based diesel engine. The fuels used to run the bio based diesel engine were diesel, virgin coconut oil and pure palm oil. The results show that the smart grid system run well at varying load and also with different fuel. Based on the experiments, average inverter efficiency was about 87%. This experiments proved that the use of biofuels had no effects to the overall system performance. Based on the results of prototype experiments, this paper will focus on design and optimization of smart micro grid system using HOMER software for Nyamuk Island. The design consists of (1) a diesel engine existing in Nyamuk Island whose fuel was diesel, (2) a lister engine whose fuel was from vegetable oil from Callophyllum inophyllum, (3) solar panels, (4) batteries and (5) converter. In this simulation, the existing diesel engine was set to operate 2 hours per day, while operating time of the lister engine has been varied with several scenarios. In scenario I, the lister engine was operated 5 hours per day, in scenario II the lister engine was operated 24 hours per day and in scenario III the lister engine was operated 8 hours per week in the weekend. In addition, a design using a modified diesel engine was conducted as well with an assumption that the modified cost was about 10% of new diesel engine cost. By modifying the diesel engine, the system will not need a lister engine. Assessments has been done to evaluate the designs, and the result shows that the optimal value obtains by the lister engine being operated for 24 hours a day in which the capacity of each component was 27 kWp PV, 7 kW lister engine, 26 kVA existing diesel engine, 40 kW converter and 128 batteries. The result is based on the lowest value of Net Present Cost (NPC) of $542.682 and Cost Of Electricity (COE) of $0.49. [ABSTRACT FROM AUTHOR]

Green infrastructure has several benefits compared to grey infrastructure in term of environmental services and sustainability, such as reducing energy consumption, improving air quality, providing carbon sequestration, and increasing property values. Nevertheless in practice, the implementation of the concept in Indonesia is still limited. Implementation of the certain concept has to be guided in planning document. In this paper, green infrastructure concept in the current spatial plan and other planning documents is assessed. The purpose of this research is to figure out how far the green infrastructure concept is integrated into planning system, based on the analysis of planning documents in Citarum Watershed and expert interviews with local stakeholders. Content analysis method is used to analyze the documents and result of interview. The result shows that green infrastructure concept has not been accommodated in spatial plan or other planning documents widely. There are some challenges in implementing the concept including reward and punishment system (incentive and disincentive), coordination, and lack of human resources. [ABSTRACT FROM AUTHOR]

The Travelling Salesman Problem (TSP) is one of the best known NP-hard problems, which means that no exact algorithm to solve it in polynomial time. This paper present a new variant application genetic algorithm approach with a local search technique has been developed to solve the TSP. For the local search technique, an iterative hill climbing method has been used. The system is implemented on the Android OS because android is now widely used around the world and it is mobile system. It is also integrated with Google API that can to get the geographical location and the distance of the cities, and displays the route. Therefore, we do some experimentation to test the behavior of the application. To test the effectiveness of the application of hybrid genetic algorithm (HGA) is compare with the application of simple GA in 5 sample from the cities in Central Java, Indonesia with different numbers of cities. According to the experiment results obtained that in the average solution HGA shows in 5 tests out of 5 (100%) is better than simple GA. The results have shown that the hybrid genetic algorithm outperforms the genetic algorithm especially in the case with the problem higher complexity. [ABSTRACT FROM AUTHOR]

Indonesia is the country with the largest muslim population in the world, most of the inhabitants do salat every day. THR (Total Hip Replacement) patients are prohibited from doing salat in normal gait. It leads to the damage of the hip joint prostheses due to impingement and dislocation. This paper reports the design of a pin- on-ring tribometer which is used to measure and analyze the wear volume and the impingement of hip joint prostheses during salat. The modifications of the femoral head and acetabular cup holder are performed to design the reciprocating motion for the movement of the hip prostheses. The interesting finding of the present research is a new mechanism of linked-bar which leads to the feasibility of the measurement of the wear volume and the impingement for THR patients during salat. [ABSTRACT FROM AUTHOR]

SMK is the vocational education that prepare students to be able to work. So that the graduates should have the competence needed by business and industry. Competencies required by business and industry is always changing according to the development of science and technology. SMK then have to change and evolve. The development of vocational can utilize through teachers internships program in business and industry, so the teacher as a mediator for vocational development. Teachers Internships program in the business and industry is to meet the needs for vocational and business and industry. The present paper describes a study on the teachers' industrial internship program which is conducted through a qualitative research method on two vocational high schools that offer automotive program in Sidoarjo Regency, Indonesia, each of which is private and public school. The findings of the study is that the teachers Internships program as the contribution of industry to the development of vocational schools, the main human resource development. [ABSTRACT FROM AUTHOR]

Increasing the competence of graduates of course requires adequate facilities and infrastructure, especially practical tools in accordance with the Law of the Republic of Indonesia Number 20 of 2003 concerning the National Education System. Therefore, the purpose of this study was to measure the feasibility of practicum facilities and the level of competence of class XI students of Mechanical Engineering at SMK Muhammadiyah 1 Bantul. The results can be used as evaluation material by schools or foundations. This study used a descriptive method with a quantitative approach which is then described qualitatively. The subject were teachers of lathe subject, head of the Mechanical Engineering Department. The research objects included: the feasibility of buildings, furnishings, equipment, instructional media, and other devices as well as the level of competence of students' lathes. Data collection used observation, interviews, and documentation technique. The instruments used were observation instrument sheets and interview instruments. The data analysis technique used descriptive statistical analysis technique. Based on the results of the research that has been done, the feasibility of the lathe machining workshop facility at SMK Muhammadiyah 1 Bantul reached 72.5% so that it was included in the feasible category to support the formation of students' lathe competencies. The mean score of participants in the lathe subject was above the Minimum Graduation Criteria (MGC). This means that the competency standard for turning students of class XI Mechanical Engineering at SMK Muhammadiyah 1 Bantul has been achieved. Similar research is needed for other competencies that must be fulfilled by vocational students in the field of Mechanical Engineering so that they can be used as evaluation materials to improve the competence of graduates who are ready to face the Industrial Revolution Era 4.0. [ABSTRACT FROM AUTHOR]

Esports is one of the biggest sports games in the world. Games are expanding in Indonesia as many events are held nationally and internationally on youtube channel. The game that is now playing is Mobile Legend, PUBG, League Of Legend and Garena Freefire. Freefire was held in 2020 throught tournament system that was participated by 18 clubs Esports divided into 3 groups of 6 team. The Esports tournament will go throught the regular season and playoff group. The problem that researchers is to determine the prediction of victory throught several research method on Freefire Esports data sources. Therefore, the researcher will use the method for Freefire Esport data namely Naïve Bayes. Researchers use this method becauseNaïve Bayes can determine the data to find the highest and lowest team scores. The value that the researcher takes is based on the standings of the points that pass are taken from the results of the calculation of this Naïve Bayes Method. The purpose of this paper is to obtain accurate and normal datasets. [ABSTRACT FROM AUTHOR]

Analysis of hazard assessment to active volcanoes is crucial for risk management. The hazard map of volcano provides information to decision makers and communities before, during, and after volcanic crisis. The rapid and accurate hazard assessment, especially to an active volcano is necessary to be developed for better mitigation on the time of volcanic crises in Indonesia. In this paper, we identified the hazard parameters to develop quantitative and dynamic hazard map of an active volcano. The Guntur volcano in Garut Region, West Java, Indonesia was selected as study area due population are resided adjacent to active volcanoes. The development of infrastructures, especially related to tourism at the eastern flank from the Summit, are growing rapidly. The remote sensing and field investigation approaches were used to obtain hazard parameters spatially. We developed a quantitative and dynamic algorithm to map spatially hazard potential of volcano based on index overlay technique. There were identified five volcano hazard parameters based on Landsat 8 and ASTER imageries: volcanic products including pyroclastic fallout, pyroclastic flows, lava and lahar, slope topography, surface brightness temperature, and vegetation density. Following this proposed technique, the hazard parameters were extracted, indexed, and calculated to produce spatial hazard values at and around Guntur Volcano. Based on this method, the hazard potential of low vegetation density is higher than high vegetation density. Furthermore, the slope topography, surface brightness temperature, and fragmental volcanic product such as pyroclastics influenced to the spatial hazard value significantly. Further study to this proposed approach will be aimed for effective and efficient analyses of volcano risk assessment. [ABSTRACT FROM AUTHOR]

Graphite oxide is widely use in renewable energy application such as solar cells, fuel-cells, battery electrodes, catalyst support, etc. This paper reports the preparation of graphite oxide from Indonesian natural graphite by sodium cholate intercalation. The enrichment process of as received graphite with carbon content of 60% was carried out by using acid leaching (HF) method. The enrichment process successfully obtained graphite with carbon content 95.61% with contaminant minerals observed by EDS were magnesium and aluminum. Purified graphite was then intercalated by sodium cholate at various concentration and sonication time. The XRD results shows that preparation with concentration of sodium cholate 2 Wt.% and sonication 10 hours formed a peak characteristic of graphite oxide at 2θ=15°. In addition, the successful oxidation process designated by the C/O ratio of 15.75 observed from EDS and supported by the present of functional C-H and C-O obtained from the FTIR observation. It is concluded that the graphite oxide successfully prepared by intercalation using sodium cholate and sonication. [ABSTRACT FROM AUTHOR]

Solar energy is one of the most significant types of the sustainable and renewable energy sources that have been used in Indonesia. Photovoltaic (PV) is known as the direct conversion of the sunlight to electricity energy with the used of solar cells. There are number of different types of solar PV modules, from an ever increasing range of manufacturers. Each of them claims that they are the best for one reason or another. This paper reports the study results of energy yield measurements of different PV module technologies performed at the outdoor testing facility of the Energy Technology Center (B2TE-BPPT) Kawasan Puspiptek Serpong-Indonesia from March 2014 through February 2015. The purposes of the study wereto evaluate and compare the performances of three different PV modules during a medium term outdoor exposure at the tropical climate of Indonesia. Normalized energy yields (Y), module efficiency (η), and performance ratio (PR) were calculated for each module, and the effect of module temperature and solar irradiance on these parameters was investigated. Monocrystalline PV module was better in terms of module efficiency and overall power production. Meanwhile micromorph silicon (uc-Si) showed the lowest module efficiency, but the more power production compared with polycrystalline PV module. Module efficiency and performance ratio showed a decreasing trend with increase of module temperature. [ABSTRACT FROM AUTHOR]

In this paper, we discuss about the use of micro earthquake method in monitoring of dry steam type geothermal field in Indonesia. This study takes X geothermal field, which is the pioneer of Indonesia's geothermal development. Therefore, it should be maintained for long period by doing proper production and reinjection activities. Hypocenters of microseismic events is represented movements of reinjection fluids that means it could be space where fractured zone is formed. We use Single Event Determination (SED) method to relocate the hypocenters of microseismic event during the period of January - June 2014. About 179 events of micro earthquake were recorded on that period, these micro earthquake have magnitudes in range of 0.4 to 2.1 SR. Some of them are related to reinjection fluid from injection well INJ21. The hypocenters which is related to injection fluid from INJ21 shows that fractured zones exist on there. These fractured zones is located in geothermal reservoirs based on the geological setting. Fractured zones caused by high pressure of reinjection fluid where it happens in geothermal reservoirs containing high temperature, when reinjection water contacted with high temperature reservoir, it will be a new fractured zones because of high intensity of micro earthquake events. [ABSTRACT FROM AUTHOR]

Science teaching is basically value laden activities. One of the values tells that science is not related to any religion. This secular value is reflected to science teaching in many places, including religious country like Indonesia. However, we argue that in Indonesia science teaching should not be secular as in the Western country since one of the basic aim of National Education according to the Indonesian constitution Undang-Undang Dasar 1945, is to inculcate faith and god-fearing to One God Almighty. As we know, Indonesia is a Moslem country and has many Islamic schools in it too. Thus, it is important to design a science teaching framework base on Islamic teaching to fulfill the basic aim of National Education This paper discusses concept of nature, the key term in science, based on Islamic view that may used as a framework to develop Islamic science teaching. In Islam, science has a strong relation to religion since nature reflects the existence of the Creator. This concept is derived from the analysis of several verses from Qur'an as the main source of Islamic teaching. There are several principle can be derived from this analysis. Firstly, visible world is not the only world, but there is also the unseen world. Secondly, the nature is not merely matter that doesn't have any sacred value, but it is the indication or symbol of God existence and His Nature. Thirdly, The Qur'an and the nature are both Books of Allah that contain messages of Him, so they are complementary to each other. [ABSTRACT FROM AUTHOR]

In recent years, political figures begin to utilize social media as one of alternative to engage in communication with their supporters. Publics referred to Jokowi, one of the candidates in Indonesia presidential election in 2014, as the first politician in Indonesia to truly understand the power of social media. Social media is very important in shaping public opinion. In this paper, effect of social media on the Jokowi-fever model in a closed population will be discussed. Supporter population is divided into three class sub-population, i.e susceptible supporters, Jokowi infected supporters, and recovered supporters. For case no positive media, there are two equilibrium points; the Jokowi-fever free equilibrium point in which it locally stable if basic reproductive ratio less than one and the Jokowi-fever endemic equilibrium point in which it locally stable if basic reproductive ratio greater than one. For case no negative media, there is only the Jokowi-fever endemic equilibrium point in which it locally stable if the condition is satisfied. Generally, for case positive media proportion is positive, there is no Jokowi-fever free equilibrium point. The numerical result shows that social media gives significantly effect on Jokowi-fever model, a sharp increase or a sharp decrease in the number of Jokowi infected supporters. It is also shown that the boredom rate is one of the sensitive parameters in the Jokowi-fever model; it affects the number of Jokowi infected supporters. [ABSTRACT FROM AUTHOR]

Although Indonesia is one of the biggest cocoa beans producers in the world, Indonesian cocoa beans are oftenly of low quality and thereby frequently priced low in the world market. In order to improve the quality, adequate post-harvest cocoa processing techniques are required. Fermentation is the vital stage in series of cocoa beans post harvest processing which could improve the quality of cocoa beans, in particular taste, aroma, and colours. During the fermentation process, combination of microbes grow producing metabolites that serve as the precursors for cocoa beans flavour. Microbial composition and thereby their activities will affect the fermentation performance and influence the properties of cocoa beans. The correlation could be reviewed using a kinetic model that includes unstructured microbial growth, substrate utilization and metabolic product formation. The developed kinetic model could be further used to design cocoa bean fermentation process to meet the expected quality. Further the development of kinetic model of cocoa bean fermentation also serve as a good case study of mixed culture solid state fermentation, that has rarely been studied. This paper presents the development of a kinetic model for solid-state cocoa beans fermentation using an empirical approach. Series of lab scale cocoa bean fermentations, either natural fermentations without starter addition or fermentations with mixed yeast and lactic acid bacteria starter addition, were used for model parameters estimation. The results showed that cocoa beans fermentation can be modelled mathematically and the best model included substrate utilization, microbial growth, metabolites production and its transport. Although the developed model still can not explain the dynamics in microbial population, this model can sufficiently explained the observed changes in sugar concentration as well as metabolic products in the cocoa bean pulp. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is looking at the relationship between the factors of technical, financial and legal with enterprise value in mergers and acquisitions of coal companies in Kalimantan, Indonesia over the last 10 years. Data obtained from secondary data sources in the company works and from published data on the internet. The data thus obtained are as many as 46 secondary data with parameters resources, reserves, stripping ratio, calorific value, distance from pit to port, and distance from ports to vessels, production per annum, the cost from pit to port, from port to vessel costs, royalties, coal price and permit status. The data was analysis using structural equation modeling (SEM) to determine the factors that most significant influence enterprise value of coal company in Kalimantan. The result shows that a technical matter is the factor that most affects the value of enterprise in coal merger and acquisition company. Financial aspect is the second factor that affects the enterprise value. [ABSTRACT FROM AUTHOR]

The interaction between groundwater and Cikapundung river water has not changed significantly in 16 years of period. This paper revisit the similar research based on 43 measurement points: 13 dug wells, 2 springs, and 24 river, distributed along the riverbank at Curug Dago to Batununggal segment. The field measurements were taken in rainy season of April to May 2014 using portable instruments. Six parameters were measured: water level, temperature, total dissolved solids (TDS), dissolved-oxygen (DO), and pH. The new model is unable to detect significant change in water flow, however it finds two local anomalies in Dago Pojok and Cikapayang area. Both locations show local drawdown circle which can induce influent stream in overal effluent environment. Moreover, water quality parameters indicate mixing processes between groundwater and river water, with erratic pattern both in effluent and influent stream. Also some DO and TDS readings exceed the permissible limit. These values suggest a lifted groundwater mineralization from organic and non-organic sources and change of chemical stability. The source of contamination is still under further examination. [ABSTRACT FROM AUTHOR]

Quantitative-spatial analysis has been applied to 295 samples of shallow groundwater quality data from Bandung-Soreang Groundwater Basin (BSGwB) taken in 1997, 1998, 2007, 2010, and 2011. This paper discuss the use of variogram using geoR and generalised additive model (GAM) using mgcv R-package to identify the spatial distribution and mixing process betwee groundwater and Cikapundung river water. The variograms show significant water quality trend in north-south direction, and in the direction to the Cikapundung River. From the GAM tests using gaussian and gamma family, some significant elements can be identified: (1) geological control from Fe, Mn, Na concentration; (2) agricultural control from NO2, NO3 concentration; and (3) other surficial control from EC, CO3, CO2, SO4 concentration. Both analysis suggest the close interaction between groundwater and river water and the occurrence of mixing between both. [ABSTRACT FROM AUTHOR]

Deriving unit hydrograph is very important in analyzing watershed's hydrologic response of a rainfall event. In most cases, hourly measures of stream flow data needed in deriving unit hydrograph are not always available. Hence, one needs to develop methods for deriving unit hydrograph for ungagged watershed. Methods that have evolved are based on theoretical or empirical formulas relating hydrograph peak discharge and timing to watershed characteristics. These are usually referred to Synthetic Unit Hydrograph. In this paper, a gamma probability density function and its variant are used as mathematical approximations of a unit hydrograph for Citarum Watershed. The model is adjusted with real field condition by translation and scaling. Optimal parameters are determined by using Particle Swarm Optimization method with weighted objective function. With these models, a synthetic unit hydrograph can be developed and hydrologic parameters can be well predicted. [ABSTRACT FROM AUTHOR]

Of the 250.000 species of higher plants known to exist on earth, 30.000 species are to be found in the tropical region of Indonesia. Many of these tropical plants have been employed as medicines by the indigeneous people in both rural and urban areas. However, only a relatively small amount of them have been thoroughly studied for all aspects of their potential therapeutic value in medicine. The search for plant chemicals with potential activity for treatment of deseases and industrial utilization have been initiated successfully in our laboratories. in combination with biological evaluation. Many members of the genus Artocarpus and Morus (Moraceae) are used in tradirional folk medicine in the tropical and subtropical regions of south and southeast Asia. In this paper, our recent works on the chemistry of Artocarpus lanceifolius and Morus macroura the endemic and endangered species to Indonesia, which led to the isolation of many new, unique and novel phenolic compounds and their bioactivities will be presented. [ABSTRACT FROM AUTHOR]

Coastal area of Gunungkidul Regency is one of the areas prone to tsunami in Indonesia. In contrary, currently, this area is very intensively developed as one of the favourite tourism destination. This paper is aimed at explaining tsunami risk and a mitigation type in Gunungkidul Area, Yogyakarta. Digital elevation model (DEM) and coastal morphology were used to generate tsunami hazard map. Vulnerability was analysed by utilizing land use data. Information from previous studies (e.g. from GTZ) were also considered for analysis. Tsunami risk was classified into three classes, i.e. high risk, medium risk, and low risk and visualized in the form of tsunami risk map. Tsunami risk map is a tool which can be used as disaster reduction instrument, such as for evacuation routes planning. Based on the preliminary results of this research, it is clear that tsunami risk in this area is varied depend on the morphological condition of the location. There are five coastal area selected as the location, i.e. Ngrenehan, Baron, Sepanjang, Pulang Sawal, and Sadeng. All locations have the high risk zone to tsunami, especially for bay area. Evacuation routes were generated for all locations by considering the local landscape condition. There are several differences of evacuation ways for each location. [ABSTRACT FROM AUTHOR]

The liquefactions phenomena have been reported after a shocking 6.5Mw earthquake hit Yogyakarta province in the morning at 27 May 2006. Several researchers have reported the damage, casualties, and soil failure due to the quake, including the mapping and analyzing the liquefaction phenomena. Most of them based on SPT test. The study try to draw the liquefaction susceptibility by means the shear velocity profiling using modified Multichannel Analysis of Surface Waves (MASW). This paper is a preliminary report by using only several measured MASW points. The study built 8-channel seismic data logger with 4.5 Hz geophones for this purpose. Several different offsets used to record the high and low frequencies of surface waves. The phase-velocity diagrams were stacked in the frequency domain rather than in time domain, for a clearer and easier dispersion curve picking. All codes are implementing in Matlab. From these procedures, shear velocity profiling was collected beneath each geophone's spread. By mapping the minimum depth of shallow water table, calculating PGA with soil classification, using empirical formula for saturated soil weight from shear velocity profile, and calculating CRR and CSR at every depth, the liquefaction characteristic can be identify in every layer. From several acquired data, a liquefiable potential at some depth below water table was obtained. [ABSTRACT FROM AUTHOR]

Indonesia has a huge amount of biodiversity, which may contain many biomaterials for pharmaceutical application. These resources potency should be explored to discover new drugs for human wealth. However, the bioactive screening using conventional methods is very expensive and time-consuming. Therefore, we developed a methodology for screening the potential of natural resources based on bioinformatics. The method is developed based on the fact that organisms in the same taxon will have similar genes, metabolism and secondary metabolites product. Then we employ bioinformatics to explore the potency of biomaterial from Indonesia biodiversity by comparing species with the well-known taxon containing the active compound through published paper or chemical database. Then we analyze drug-likeness, bioactivity and the target proteins of the active compound based on their molecular structure. The target protein was examined their interaction with other proteins in the cell to determine action mechanism of the active compounds in the cellular level, as well as to predict its side effects and toxicity. By using this method, we succeeded to screen anti-cancer, immunomodulators and anti-inflammation from Indonesia biodiversity. For example, we found anticancer from marine invertebrate by employing the method. The anti-cancer was explore based on the isolated compounds of marine invertebrate from published article and database, and then identified the protein target, followed by molecular pathway analysis. The data suggested that the active compound of the invertebrate able to kill cancer cell. Further, we collect and extract the active compound from the invertebrate, and then examined the activity on cancer cell (MCF7). The MTT result showed that the methanol extract of marine invertebrate was highly potent in killing MCF7 cells. Therefore, we concluded that bioinformatics is cheap and robust way to explore bioactive from Indonesia biodiversity for source of drug and another pharmaceutical material. [ABSTRACT FROM AUTHOR]

In Indonesia, herbal medicines are usually produced by small and medium enterprises which are relatively low in quality control. The purpose of this paper is to report that we have developed a taste sensor system with global selectivity, i.e., electronic tongue (e-tongue) for differentiation of Indonesian herbal medicines. The e-tongue was composed of five kinds of ion selective electrodes as working electrodes, data acquisition system, and pattern recognition system. Each ion selective electrode (ISE) was built by attaching lipid/polymer membrane. For this purpose, the five kinds of membranes were built by mixing lipid, plasticizer (nitrophenyl octyl ether/NPOE), polyvinyl chloride (PVC), and tetrahydrofuran (THF). In this study, we employed five kinds of lipid, namely oleic acid (OA), dioctyl phosphate (DOP), decyl alcohol (DA), dodecylamine (DDC), and trioctyl methyl ammonium chloride (TOMA). In this case, the membranes transform information of taste substances into electric signal. The five kinds of Indonesian herbal medicine were purchased from local supermarket in Yogyakarta, i.e., kunyit asam (made from turmeric and tamarind), beras kencur (made from rice and kencur), jahe wangi (made from ginger and fragrance), sirih wangi (made from betel leaf), and temulawak (made from Javanese ginger). Prior to detecting the taste from the Indonesian herbal medicine samples, each ion selective electrode was tested with five basic taste samples, i.e., for saltiness, sweetness, umami, bitterness, and sourness. All ISEs showed global selectivity to all samples. Furthermore, the array of ISEs showed specific response pattern to each Indonesian herbal medicine. For pattern recognition system, we employed principle component analysis (PCA). As a result, the e-tongue was able to differentiate five kinds of Indonesian herbal medicines, proven by the total variance of first and second principle components is about 93%. For the future, the e-tongue may be developed for quality control application in herbal medicine industries. [ABSTRACT FROM AUTHOR]

Multivariate Markov switching models able to provide useful information on the study of structural change data since the regime switching model can analyze the time varying data and capture the mean and variance in the series of dependence structure. This paper will investigates the oil price and gold price effects on Malaysia, Singapore, Thailand and Indonesia stock market returns. Two forms of Multivariate Markov switching models are used namely the mean adjusted heteroskedasticity Markov Switching Vector Error Correction Model (MSMH-VECM) and the mean adjusted heteroskedasticity Markov Switching Vector Error Correction Model with exogenous variable (MSMH-VECMX). The reason for using these two models are to capture the transition probabilities of the data since real financial time series data always exhibit nonlinear properties such as regime switching, cointegrating relations, jumps or breaks passing the time. A comparison between these two models indicates that MSMH-VECM model able to fit the time series data better than the MSMH-VECMX model. In addition, it was found that oil price and gold price affected the stock market changes in the four selected countries. [ABSTRACT FROM AUTHOR]

Migration is important issue for seismic imaging in complex structure. In this decade, depth imaging becomes important tools for producing accurate image in depth imaging instead of time domain imaging. The challenge of depth migration method, however, is in revealing the complex structure of subsurface. There are many methods of depth migration with their advantages and weaknesses. In this paper, we show our propose method of pre-stack depth migration based on time domain inverse scattering wave equation. Hopefully this method can be as solution for imaging complex structure in Indonesia, especially in rich thrusting fault zones. In this research, we develop a recent advance wave equation migration based on time domain inverse scattering wave which use more natural wave propagation using scattering wave. This wave equation pre-stack depth migration use time domain inverse scattering wave equation based on Helmholtz equation. To provide true amplitude recovery, an inverse of divergence procedure and recovering transmission loss are considered of pre-stack migration. Benchmarking the propose inverse scattering pre-stack depth migration with the other migration methods are also presented, i.e.: wave equation pre-stack depth migration, waveequation depth migration, and pre-stack time migration method. This inverse scattering pre-stack depth migration could image successfully the rich fault zone which consist extremely dip and resulting superior quality of seismic image. The image quality of inverse scattering migration is much better than the others migration methods. [ABSTRACT FROM AUTHOR]

Tsunami is a series of wave trains which travels with high speed on the sea surface. This traveling wave is caused by the displacement of a large volume of water after the occurrence of an underwater earthquake or volcano eruptions. The speed of tsunami decreases when it reaches the sea shore along with the increase of its amplitudes. Two large tsunamis had occurred in the last decades in Indonesia with huge casualties and large damages. Indonesian Tsunami Early Warning System has been installed along the west coast of Sumatra. This early warning system will give about 10-15 minutes to evacuate people from high risk regions to the safe areas. Here in this paper, a mathematical model for Tsunami evacuation is presented with the city of Padang as a study case. In the model, the safe areas are chosen from the existing and selected high rise buildings, low risk region with relatively high altitude and (proposed to be built) a flyover ring road. Each gathering points are located in the radius of approximately 1 km from the ring road. The model is formulated as an optimization problem with the total normalized evacuation time as the objective function. The constraints consist of maximum allowable evacuation time in each route, maximum capacity of each safe area, and the number of people to be evacuated. The optimization problem is solved numerically using linear programming method with Matlab. Numerical results are shown for various evacuation scenarios for the city of Padang. [ABSTRACT FROM AUTHOR]

Fish and its processed products are the most affordable source of animal protein in the diet of most people in Indonesia. The goal in production planning is to meet customer demand over a fixed time horizon divided into planning periods by optimizing the trade-off between economic objectives such as production cost and customer satisfaction level. The major decisions are production and inventory levels for each product and the number of workforce in each planning period. In this paper we consider the management of small scale traditional business at North Sumatera Province which performs processing fish into several local seafood products. The inherent uncertainty of data (e.g. demand, fish availability), together with the sequential evolution of data over time leads the production planning problem to a nonlinear mixed-integer stochastic programming model. We use scenario generation based approach and feasible neighborhood search for solving the model. The results which show the amount of each fish processed product and the number of workforce needed in each horizon planning are presented. [ABSTRACT FROM AUTHOR]

Renewable and sustainable energy is increasingly gaining interest in current research circles due to the debates on renewable energy resources. It is essential for scientists and researchers to search for solutions in renewable energy resources, with effective technologies, and low cost in operation and maintenance. Hydro resources can be considered a potential renewable energy resource. The traditional water wheel with simple construction coupled with a basic concept of technology can be utilised as a renewable and sustainable rural energy system. This paper discusses the case of the water wheel as a renewable energy system employed in Padang, Indonesia. The Padang water wheel is constructed from hardwood material with a diameter of 300 cm and width of 40 cm. It is built on a river using water flow to generate the movement of the wheel. The water wheel application in the area showed that it is suitable to be utilised to elevate and distribute water to rice fields located at a higher level than the water level of the river. The water wheel capacity is about 100–120 liters/min. It could continuously irrigate ±5 ha. of the rice fields. One of the advantages of this water wheel type is to function as a green technology concept promising no negative effect on the environment. The traditional water wheel has also a big economic impact on the rural economy, increasing the productivity of the rice fields. The people of Padang live in a water landscape encompassing the water wheel as an ubiquitous part of their lives, hence they relate to it and the technology of fabrication as well as the utilisation, making it an amenable and effective technology, finding relevance in the modern world. [ABSTRACT FROM AUTHOR]

This study discuss about the SPINNOR (Small Power Reactor, Indonesia, No On-site Refuelling) and the VSPINNOR (Very Small Power Reactor, Indonesia, No On-site Refuelling) which are small lead-bismuth cooled nuclear power reactors with fast neutron spectrum that could be operated for more than 10 or 15 years without on-site refuelling. They are based on the concept of a long-life core reactor developed in Indonesia since early 1990 in collaboration with the Research Laboratory for Nuclear Reactors of the Tokyo Institute of Technology (RLNR TITech). The reactor cores are designed to have near zero (less then one effective delayed neutron fraction) burn-up reactivity swing during the whole course of their operation to avoid a possibility of prompt criticality accident. The basic concept is that central region of the reactor core is filled with fertile (blanket) material. During the reactor operation fissile material accumulates in this central region, which helps to compensate fissile material loss in the peripheral core region and also contributes to negative coolant loss reactivity effect. A concept of high fuel volume fraction in the core is applied to achieve smaller size of a critical reactor. In this paper we consider to add Np-237 to the fuel to enhance non proliferation characteristics of the systems. The effect of Np-237 amount variation is discussed. [ABSTRACT FROM AUTHOR]

In this paper I shall give a short history of the development of neutron scattering at the Research Centre for Nuclear Techniques (PPTN), in Bandung, and the early development of a more advanced facilities at the Neutron Scattering Laboratory (NSL BATAN), Centre of Technology for Nuclear Industrial Materials, in Serpong. The first research reactor in Indonesia was the TRIGA MARK II in Bandung, which became operational in 1965, with a power of 250 KW, upgraded to 1 MW in 1971, and to 2 MW in 2000. The neutron scattering activities was started in 1967, with the design and construction of the first powder diffractometer, and put in operation in 1970. It was followed by the second instrument, the filter detector spectrometer built in 1975 in collaboration with the Bhabha Atomic Research Centre (BARC), India. A powder diffractometer for magnetic studies was built in 1980, and finally, a modification of the filter detector spectrometer to measure textures was made in 1986. A brief description of the design and construction of the instruments, and a highlight of some research topics will be presented. Early developments of neutron scattering activities at the 30 MW, RSG-GAS reactor in Serpong in choosing suitable research program, which will be mainly centred around materials testing/characterization, and materials/condensed matter researches has been agreed. Instrument planning and layout which were appropriate to carry out the program had been decided. Manpower development for the neutron scattering laboratory is a severe problem. The efforts to overcome this problem has been solved. International Cooperation through workshops and on the job trainings also support the supply of qualified manpower. [ABSTRACT FROM AUTHOR]

The modern banking industry provides its best services through various transaction channels, one of them and currently plays an important role is an online service using a website. This online service presents new problems, especially related to malware attacks and data stealing. The risk of this attack can cause financial losses for banks and bank customers. There are many ways in banking to protect their online services to reduce and mitigate the risks. Banking as a service provider does invest in hardware and software security to achieve safe and comfortable facilities for customers. On the client-side, the role of the browser on the client becomes essential because the process of data theft through web vulnerabilities often occurs on the client-side. On the server-side, they are adding declarations of security response headers on the web to reduce the risk of attack. The security response header is indicating the commitment of web service providers to provide a secure environment. In this paper, the security header implementation will be measured on the banking website in Indonesia. [ABSTRACT FROM AUTHOR]

Coffee pulp is an agro-industrial waste that has an abundant presence in Indonesia, up to 612.000 tons in 2018. Up to 6,5% of coffee pulp's dry weight is pectin. So, the coffee pulp has potential as a substrate for pectinase production. This study aims to acknowledge the utilization of coffee pulp for pectinase production using a solid-state fermentation method by Aspergillus sp. VTM5. Spore suspensions of Aspergillus sp. VTM5 with 108 spores/ml density are inoculated to coffee pulp substrate and incubated for 0 to 168 hours at 30°C. Characterization of pH testing with 250 µl of crude pectinase plus 250 µl of acetate buffer (pH 3-5) and phosphate buffer (pH 5.5-8). Enzyme activity assay using the Somogyi-Nelson Method. Optimum incubation time Aspergillus sp. VTM5 in producing pectinase is at 72 hours and the reducing sugar concentrations are 85,849 µg/ml. The optimum pH for pectinase activity is 4,5 and stable at pH 3-5. These results indicate that coffee pulp can be utilized as a substrate for pectinase production using a solid-state fermentation method by Aspergillus sp. VTM5. Purification of pectin content in the coffee pulp, purification, and characterization of the enzyme is needed to improve enzyme activity. [ABSTRACT FROM AUTHOR]

Sago is a plant widely cultivated in Indonesia with a planting area of 1.128 million ha. Sago waste, especially sago pulp, has enough starch so that it can be used as a substrate for amylolytic bacteria. Amylase enzymes produced by bacteria have the potential to be applied in the industrial sector, food, medicine, and also used to recycle waste. This study aimed to obtain amylolytic bacteria isolated from the sago pulp industry in Palopo, South Sulawesi and observe the amylase activity of these bacteria. Amylolytic bacteria were isolated from sago pulp using selective media. The pure isolate was then filtered and the ability to produce the amylase enzyme was observed. Nine amylolytic bacterial isolates were filtered based on qualitative tests. Four bacterial isolates, 2B, 2D, 1C, and 4A showed high amylolytic index, 9.00 mm, 7.28 mm, 5.75 mm, and 4.67 mm, respectively. The highest amylase activity based on quantitative tests was shown by isolates 2B (3.62 units/mL). Based on the results of the study, it was shown that the bacteria isolated from sago pulp have good potential to produce amylase. [ABSTRACT FROM AUTHOR]

This paper reports on the current situation of women in physics in Indonesia. Statistics show that there is an imbalance in the number of male and female physicists in Indonesia. An overview by one of the very few female professors in physics in Indonesia also shows how women struggle in their careers. A Women in Physics organization will be established under the Indonesian Physical Society in October 2014. [ABSTRACT FROM AUTHOR]

To win the global competition and sustain the business, small and medium enterprise shall implement a reliable information technology application to support their customer data base, production and sales as well as marketing management. This paper addresses the implementation of Customer Relationship Management (CRM) in small and medium enterprise, CV. Densuko Jaya. It is a small and medium enterprises in Semarang, Central Java, Republic of Indonesia deal with rubber processing industry supply chain. ADDIE model utilized in study to setup the CRM functionality at these enterprises. The aim of the authors is to present the benefits resulting from the application of CRM technologies at these enterprises to solve their chronicle issues in the field of integrated customer data base, production management process and sales automation in order to boost their business in the near future. Training and coaching have been delivered to the enterprises staffs and management to ensure that they can execute the system. [ABSTRACT FROM AUTHOR]

Improved shrimp farming affects the groundwater quality conditions. Assessment of shrimp farming impact on groundwater quality conventionally has less accuracy. This paper presents the implementation of Analytical Hierarchy Process (AHP) method for assessing shrimp farming impact on groundwater quality. The data used is the impact data of shrimp farming in one of the regions in Indonesia from 2006-2016. Criteria used in this study were 8 criteria and divided into 49 sub-criteria. The weighting by AHP performed to determine the importance level of criteria and sub-criteria. Final priority class of shrimp farming impact were obtained from the calculation of criteria’s and sub-criteria’s weights. The validation was done by comparing priority class of shrimp farming impact and water quality conditions. The result show that 50% of the total area was moderate priority class, 37% was low priority class and 13% was high priority class. From the validation result impact assessment for shrimp farming has been high accuracy to the groundwater quality conditions. This study shows that assessment based on AHP has a higher accuracy to shrimp farming impact and can be used as the basic fisheries planning to deal with impacts that have been generated. [ABSTRACT FROM AUTHOR]

Most water sources in Nusa Tenggara Timur contain higher concentration of calcium and magnesium ions, which is known as hard water. Long-term consumption of hard water can cause kidney dysfunction, which may lead to the other diseases such as cerebrovascular disease, diabetes and others. Therefore, understanding the effects of hard water consumption on kidney function is of importance. This paper studies the transmission dynamics of kidney dysfunction due to the consumption of hard water using a mathematical model. We propose a new deterministic mathematical model comprising human and water compartments and conduct a global sensitivity analysis to determine the most influential parameters of the model. The Routh-Hurwitz criterion is used to examine the stability of the steady states. The results shows that the model has two steady states, which are locally stable. Moreover, we found that the most influential parameters are the maximum concentration of magnesium and calcium in the water, the increase rate of calcium and magnesium concentration in the water and the rate of effectiveness of water treatment. The results suggest that better water treatments are required to reduce the concentration of magnesium and calcium in the water. This aid in minimizing the probability of humans to attract kidney dysfunction. Furthermore, water-related data need to be collected for further investigation. [ABSTRACT FROM AUTHOR]

Nanotechnology today is regarded as a revolutionary technology that can help to address the key needs related to energy, environment, health and agriculture in developing countries. This paper is a short review on the development and challenges of nanotechnology in Indonesia. Nanotechnology offers great potential benefits, there is emerging concerns arising from its novel physicochemical properties. The main applications of nanotechnology in the different sectors which is vital and its economic impact in Indonesia is also discussed. The achievment and development of nanotechnology including synthesis and dispersion of nanoparticles (NPs) and its applications in various fields is briefly addressed in Nanotehcnology and Graphene Research Center, Universitas Padjadjaran (Unpad). Despite significant progress in developmental goals, many challenges in the development of nanotechnology proccesing need to be resolved such as support infrastructure and evolution of new form of collaborative arrangements between various sectors and policies which is emerged as an important factor enabling development. [ABSTRACT FROM AUTHOR]