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This paper presents the conceptual design of hybrid energy system used in railway application. The hybrid system with batteries and energy storage double-layer capacitor is a new technology that is used under extreme climatic conditions, especially in daytime temperature up to 50°C, high relative humidity, dust and heavy rain. It is a combination of double-layer capacitors and traction batteries. It draws power both externally and from braking energy. In order to reduce CO2 emissions to the environment, energy-saving drives and energy storage are used. Also, in public transportation, Sitras Hybrid Energy System (HES), hybrid energy storage system for trams, has been developed which combines a double-layer capacitor with a nickel-metal hydride battery. The storage not only allows driving without overhead lines, it also enables braking energy to be recovered. A reliable cooling system is required to ensure that the performance of the battery and the capacitor storage is maintained for as long as possible. The results of finite element model showed the robustness for railway application. The computational model refers to proof of static and dynamic strength in accordance with EN12663. A cooling system for a tram using this innovative technology was designed and qualified for the "Qatar Education City People Mover System (PMS)" project.

Astiani D, Widiastuti T, Ekamawanti HA, Ekyastuti W, Roslinda E, Mujiman. 2022. The partial contribution of CO2-emission losses from subsidence in small-holder oil palm plantation on a tropical peatland in West Kalimantan, Indonesia. Biodiversitas 23: 6539-6545. Carbon storage in tropical peat ecosystems over thousands of years, especially within peat soil, is in huge quantity. Degradation of peat ecosystems is generally caused by human factors, whether intentional or not, damaging the carbon storage function of tropical peatlands, where forest clearing, drainage development, and burning of land converted to agriculture and plantations result in significant greenhouse gas emissions. Tropical peat in the Kubu Raya District of West Kalimantan, which has a relatively large area of peat, has been degraded as a cause of uncontrolled drainage and land fires caused by a lack of management after its forest cover was lost. The main impact is an increase in peat CO2 emissions due to changes in land use, especially lowering groundwater levels. Subsequently, the subsidence process also occurs after land clearing. This study aims to obtain the proportion of carbon biomass loss due to the CO2 emission process from reducing the peat layer due to subsidence. Data collection was executed for two years, where CO2 emission was monitored bi-weekly, and the subsidence was measured bi-monthly. The results demonstrate groundwater levels dictate the peat CO2 emission and subsidence. Lowering GWL 30 to -85 cm increases CO2 by more than three times, approximately. The rate of peat subsidence shows similar trends to the emission. The proportion of peat biomass loss on CO2 emission was between 58.9 to 73.5%, except for GWL ~5 cm, where the proportion was the highest at 82%. The results of this study are beneficial in explaining the part of the subsidence that impacts the sources of CO2 emissions from the small-holder oil palm and GWL management on peatlands.

Astiani D, Curran LM, Mujiman, Ratnasari D, Salim R, Lisnawaty N. 2018. Edge effects on biomass, growth, and tree diversity of a degraded peatland in West Kalimantan, Indonesia. Biodiversitas 19: 272-278. Tropical forested peatlands in Indonesia are threatened by logging and clearing which reduce their ecosystem functions and degrade the environment. Land use change activities disturbed intact forests, resulted in landscape fragmentation. Scattered forest matrices resulted in forest edge areas, which will considerably affect the forest biotic and abiotic conditions, as well as forest tree dynamics within the edge sites. The goal of this study was to investigate the effect of forest edge on perimeter of the forest fragment on the forest biomass stock, growth, tree basal area as well as species composition, richness and abundance in a degraded peatland forest in West Kalimantan. A twelve-ha forest was divided into 35 plots in the interior forest and 13 at the forest edge; each plot was 50 m by 50 m in size based on their abiotic conditions such as light and temperatures. Leaf Area Index (LAI) was measured in each plot of both forest edge and interior sites using Licor-2100. The results indicated that even though the biomass levels maintained relatively moderate to high levels on both sites, forest edge significantly lowered forest biomass by 32%, reduced 23-25% of tree-biomass growth per unit area for both tree diameter of 10-20 cm and >20 cm. There was a shift of tree species composition, 76 species were found on both sites, 24 species were not found in edge site, but present in the interior site and 10 species were found only in edge site. Peatland forest matrix created forest edges that are lowering peatland forest roles in sequestering carbon per unit area and reducing species diversity. Peatland forest restoration should be conducted to reduce forest matrices and to lower the edge effects.

Astiani D, Curran Lm, Mujiman, Salim R. 2017. Throughfall quantity and carbon input beneath canopy gaps of varying size in degraded tropical peatland forest of West Kalimantan, Indonesia. Biodiversitas 18: 1258-1264. Tropical peatland forest ecology, is mostly determined by peatland hydrological conditions. However, deforestation, forest degradation, or any other environmental disturbance can transform hydrological patterns and processes for peatland water movement, and thus alter carbon flow via water in this type of ecosystem. These changes arise from alteration in the quantity of throughfall (water that falls through plant canopies), in its interception, and in its evaporation to the atmosphere from vegetation surfaces. We have investigated the effects of a gradient of forest degradation levels, represented by canopy gaps (open, intermediate and closed), on throughfall quantity to the peatland forest floor. Nine plots, 50m x 50m in size, were stratified into the three forest canopy gap classes. Nine bucket collectors were used for throughfall, and tipping bucket rain gauges were set up for precipitation monitoring. Results show that annual precipitation in the area was 3,168.8 ± 111.3 mm, with a mean monthly rainfall of 264.0 ± 15.3 mm. Throughfall monitoring demonstrated that closed canopies transferred significantly more water as throughfall than intermediate or open canopies, due to differences in their effect on water movement through the canopies. The proportion of precipitation that passed through the canopies to the forest floor as throughfall was measured to be 76.5%, 77.3% and 89.4 %, or 202, 204 and 236 mm per month, respectively for open, intermediate, and closed canopies. It was found that higher levels of canopy cover resulted in significantly higher amounts of total organic carbon (TOC) content per unit of throughfall; specifically, 2.5 2.8 and 3.4 mg L-1 respectively for the open, intermediate, and closed canopies. When coupled with the higher quantity of throughfall in the closed canopy, the higher concentration of carbon results in a greater amount of carbon brought to the peatland forest floor by the throughfall pathway. This could also have impacts for other nutrients in the peatland soil.

Currently, tropical peatland forests are under considerable pressure because of increasing deforestation and degradation of forests. In Kalimantan, degradation and deforestation of peatland forests are driven primarily by industrial logging, expansion of agricultural activities through primarily conversion of forests to agricultural land and oil palm plantations. By the establishment of intensive drainage, it can induce wildfires in peatland. Unmanaged drainage ditches will alter water table levels within the site adjacent to the drainage including to surrounding peatland forest. Water table assessments were conducted before and after peatland drainage on 2007/2009 and 2012/2015 in Kubu Raya, West Kalimantan. This paper studies the effect of drainage ditches into the peatland water table. Results show the establishment of drainage ditches on this peatland landscape lowered the water table by more than 3 times from ~11.7 cm (SE = 1.5, n = 5) to ~37.3 cm (SE = 2.1 cm, n = 26). The effect on the water table was in drier months of July-August. Lowering the water table level altered worst the soil micro climate, peat temperature and peat water content. The results indicate the land use changes in peatland with the establishment of drainage affects peatland water table currently. In the area of less than 500 m from the drainage, the water level tends to lower toward the drainage feature. Therefore, recovery of peatland forests should be initiated by managing the landscape hydrology (i.e. water table) to restore the ecosystem and to protect the remaining peat swamp forest

Berdasarkan realitas kehidupan berbangsa dan bernegara saat ini, terutama terkait dengan berbagai kasus hoaks dalam komunikasi sosial, pada dasarnya, bangsa Indonesia sangat membutuhkan kesantunan, khususnya kesantunan berbahasa. Kebutuhan itu tidak hanya terkait dengan persoalan pelestarian nilai-nilai budaya leluhur, tetapi jauh lebih pragmatis dari itu adalah masalah penciptaan kedamaian warga negara, pembangunan karakter bangsa, yang se-kaligus menjadi upaya pengembangan aset wisata budaya di era ini untuk menuju Indonesia emas yang maju. Dilihat dari sisi ini, secara sosial maupun ekonomik, kesantunan berbahasa menduduki posisi strategis bagi pemba-ngunan nasional secara keseluruhan. Dengan demikian, pembelajaran kesantunan berbahasa secara formal di sekolah-sekolah menjadi sangat penting dan strategis untuk diadakan. Bagaimana esensi dan di mana posisi pembelajaran kesantunan berbahasa ini dilaksanakan? Artikel ini menawarkan diskusi berkenaan dengan dua pertanyaan tersebut. Katakunci : pembelajaran, kesantunan berbahasa, Indonesia emas Based on the reality of our nation and state life today, especially related to various cases of hoax in social communication, basically, Indonesian people need politeness, especially language politeness. The need is not only related to the issue of preservation of cultural values of ancestors, but also related to the problem of creating peace among citizen, building the nation's character, which is at the same time an effort to develop cultural tourism assets in this era to move towards an advanced golden Indonesia. Viewed from this side, socially and economically, politeness in language occupies a strategic position for national development as a whole. Thus, the learning of politeness in formal language in schools becomes very important and strategic to implement. How is the essence and where is this politeness learning position carried out? This article offers a discussion regarding these two questions. Keywords : Learning, politeness, Indonesia gold

Indonesian peatland forest is considered a huge sink of tropical carbon and thereby make significant contribution to global terrestrial carbon storage. However, landcover and landuse changes in this ecosystem have incurred a synergistic exposure to drought and wildfires. Deforestation and forest degradation through combustion and decomposition of forest biomass and soil carbon have become global issues because of their greenhouse gas contribution to global climate change. Thus fire-driven carbon losses in these peatlands have increased the need to evaluate the impacts of fire at a landscape scale. In 6–10 week dry periods from January to April 2014 and in January 2015, wildfires burnt peatland forest in Kubu Raya, West Kalimantan province (Indonesian Borneo). An assessment was conducted to provide more reliable estimates of the effects of fire on aboveground and soil carbon losses and their dynamics in the coastal peatlands of the province. Carbon loss from combustion of both aboveground biomass and peat soil was substantial. Moreover, CO2 emission from soil respiration at the burnt peat surface increased 46% over the first 9 months after the fire. This study clearly showed the magnitude of fire-driven carbon loss and the scale of CO2 emission to the atmosphere arising from fire in tropical peatland forest.

The research attempts to find the deflection on a concrete slab that functions as a layer on top of a rigid pavement, the strain occurring on the pulling part as an effect of subgrade water, and the effects of static quasi loads in the middle of the concrete slab. The research adopted the experimental method with a testing object of concrete slab with a size of 1.0 x 1.0 x 0,1 m placed on top of lean concrete layer and subgrade with the size of 1.0 x 1.0 x 0,035 m and 1.0 x 1.0 x 0.4 m, respectively. Quasi-static loads were placed upon 3 (three) variations of tested objects. Variation 1 is the placing of loads on top of a concrete slab with 30% water content of the subgrade dry weight; variation 2 is the placing of loads on top of a concrete slab with 40% water content of the subgrade dry weight; and variation 3 the placing of loads on top of a concrete slab with 50% water content of the subgrade dry weight. The findings show that the carrying capacity of the concrete slab decreases. Th maximum carrying capacities of the concrete slab were 82.5 kN, 62.33 kN, and 30.06 kN for variation 1, variation 2, and variation 3, respectively.

This research was purposed to study the composite behavior and the increased capacity of reinforced concrete beam strength under flexural loading caused by external strand strength without stressing. The specimen is divided into 2 types. Type-I specimen has (150 x 300 x 3200) mm dimension with center point loading, and distance of strand clamp as (Ubars) variable; whereas, the Type-II specimen has (200 x 300 x 3200) mm dimension with third point loading, and the number of strand as variable. The test is carried out by static-monotonic loading, and displacement control. Experimental test results shows that the addition of strand on the lower surface of the beam increase the beam’s load capacity. However, the use of U- bars affects the stability of the concrete. The tighter distance of the U-bars decrease the capacity of the strengthening occured. The increased load capacity of Type I specimens, S3-150, S5-150 and S9-150 are 33.2%, 17%, and 12.1% against control beam (BK-150), respectively. Whereas, the increased capacity of the type-II beam strength of test specimens B1-200 and B2-200 are 10% and 17% against control beam (BN-200), respectively. And the increase of initial stiffness of beam Type-I test specimen S3-150, S5-150, and S9-150 are 14%, 18% and 5% against control beam (BK-150), respectively. Meanwhile, the increase of initial stiffness of Type-II beam of test specimens B1-200 and B2-200 are 21% and 24% against control beam (BN-200), respectively. This study shows that concrete and strand bonding is not compatible. The concrete has been reaching the limit strain, as well as the steel reinforcement in the concrete has been in yielded; meanwhile, strand that has fy is much higher than fy of reinforced steel, is still in elastic condition.

Perkembangan ekonomi yang mengalami tren penurunan berdampak pada pelaku bisnis yang mengakibatkan berkurangnya daya beli serta berimbas pada koperasi. Banyak anggota koperasi yang tidak mampu membayar kewajibannya sehingga terjadi pembiayaan bermasalah. Pengendalian diperlukan untuk meminimalkan pembiyaan bermasalah. Tujuan penelitian ini untuk mengetahui bagaimana Kerangka Pengendalian Comitee On Sponsoring Organization (COSO) dalam mengendalikan prosedur pemberian pembiyaan implementasi penerapan pada Koperasi Syariah Baitul Muttaqin Bandung sehingga akan meningkatkan kualitas pembiayaan. Penelitian ini merupakan penelitian kualitatif dengan menggunakan tiga metode pengumpulan data yaitu: partisipasi, observasi dan wawancara. Pengolahan data mengacu pada studi pustaka yang kemudian dianalisis dengan menggunakan analisis deskriptif dan menganalisis keseuaian antara kriteria dan praktik implementasi sistem pengendalian internal dengan menggunakan triangulasi. Hasil penelitian ini menunjukkan bahwa pengendalian internal Koperasi Syariahh Baitul Muttaqin sudah menerapkan kerangka pengendalian Comittee On Spronsoring Organization walaupun masih ada kekurangan. Efektifitas penerapan ini dapat dibuktikan dengan tingkat resiko pembiayaan bermasalah yang rendah, yakni dibawah 5%.

Illocutionary speech act is an act of speech that has the intention of conveying information to its destination so that the speech partner does something. Illocutionary speech acts are found in all aspects of daily social interactions. It is also included in the interactions contained in a drama performance Do Not Sing in the Bathroom which is performed by the Tiang Theater, Jember University. According to Searle, the form of illocutionary speech acts consists of several forms, namely representative, directive, declarative, expressive, and commissive. This study uses a qualitative research design while the type of research used is descriptive which aims toproblems in accordance with reality based on facts. The data in this research is in the form of dialogues that are told by drama characters in the performance. The source of the data in this study is a video performance documentation. Data collection techniques used in this study were documentation techniques and data transcripts. The data analysis technique used in this study consisted of three stages, namely data reduction, data presentation, and data analysis procedures (preparation, implementation, and completion). The results of this study indicate that there are forms of illocutionary speech acts in the dialogue of the characters in the drama Prohibited from Singing in the Bathroom by Teater Tiang Universitas Jember, namely: representative, directive, expressive, declarative, and commissive. the illocutionary speech act functions of the drama characters. namely: competitive, convivial, collaborative / cooperation, and conflict. Support speech partners for the illocutionary speech acts received.

The timber bridge design although economical, often has difficulty producing enough rigidity so that a solution is needed to solve it. The use of CFRP (Carbon Fiber Reinforced Polymer) as a reinforcement of structural elements if properly designed and implemented can produce an effective and efficient composite structure. The experimental study aims to analyse the strength, stiffness and ductility of flexural strengthening composite bridge glued laminated timber beams-concrete plates using CFRP layers. The dimensions of the composite glued laminated timber beams 100/180 mm and concrete plate 75/300 mm with a length of 2,480 mm. The number of specimens is 3 composite glued laminated timber beams-concrete plate consisting of 1 test beam without CFRP reinforcement, 1 test beam with one layer CFRP reinforcement, and 1 test beam with three layer CFRP reinforcement. Experimental testing of flexural loads is done with two load points where each load is placed at 1/3 span length. The test results show that the strength of composite laminated timber beams glued - concrete plates BN; BL-1; BL-2 in a row 81.32; 82.82; 82.69 kN/mm; stiffness in a row 7.51; 8.22; 6.32 kN/mm and successive ductility of 16.67; 28.83; 20.21.

The need for electricity in Indonesia and throughout the world is increasing, while most of the energy sources for electricity generation are still using fossil fuels such as oil, natural gas and coal. Fossil energy has a high level of pollution which is the cause of global warming, it is necessary to replace fossil energy that is environmentally friendly, namely renewable energy. The construction of power plants such as micro hydro power plants (PLTMh) which are located in irrigation canals or rivers with relatively small water discharge will result in low wheel rotation. The waterwheel rotation in this PLTMh system has a low rotating speed of around 200 rpm, and has a low torque or no cogging torque effect. Based on the needs in the field, a permanent Neodymium Type (NdFeB) Permanent Magnet Axial Flux Generator is built, which is specifically designed for low speeds of 200 rpm and has no cogging torque or low rotational torque effects. And it is hoped that the design of this generator can be used according to the needs of PLTMH. The results obtained in this study are, the generator can produce a voltage at a rotational speed of 200 Rpm and a frequency of 50 Hz is 100 VAC.

Astiani D, Mujiman, Curran LM. 2017. Trees of tropical peatland forest influence on variability of water and carbon input through stemflow. Biodiversitas 18: 383-388. Hydrology controls the chemical and biotic processes in peatlands, influencing interactions among vegetation, nutrient dynamics, and carbon fluxes. The effects of forest degradation revealed severe changes in the hydrological cycle such as variability of water input on forest floor, soil water storage and the ability to abstract water from soil depth. A study had been conducted to investigate part of the water cycle, the amount of water and carbon input through stemflow into peatland forest floor for 2 years. Stemflow was measured on 20 trees of each 3 blocks of forest with tree diameter ranging from 10-30 cm dbh using stemflow collectors. Then the trees were grouped to three bark types (smooth, mid, and coarse) to investigate whether it had influenced the inputs. Results showed that with mean annual precipitation of 3282 ± 128mm, annual mean stemflow for the area was 18.2% of the rainfall. Further analysis demonstrated that tree species with smoother bark textures tend to bring more water to forest floor compared to mid and coarse bark textures (46% and 42.5% more than coarse and intermediate consecutively). The carbon input also show similar trend. The results implied that tree species influence the amount of stemflow and significant amount of water could be slower down come to forest floor through this mechanism and protected forest soil. Keywords: Annual stemflow, peatland forest, hydrological flow, tree barks, tree species

Astiani D, Mujiman, Rafiastanto A. 2017. Forest type diversity on carbon stocks: Cases of recent land cover conditions of tropical lowland, swamp, and peatland forests in West Kalimantan, Indonesia. Biodiversitas 18: 137-144.Tropical forests constitute for a large concentrated carbon pools, ultimately in tropical peatland forest since this forest type sink carbon both in the vegetation and its underlying peat. However, these forests recently experienced a lot of pressures from anthropogenic disturbances. A study was conducted to estimate carbon stocks of degraded tropical lowland, swamp, and peatland forests in Kayong Utara West Kalimantan. Above ground survey was conducted using stratified sampling based on the differences in spectra of Landsat 7 ETM+ according to the land cover gradation or vegetation formations. The study area was classified based on the canopy closures and forest/landcover types and grouped into low and high degraded lowland forest, low and high degraded peat forest, low and high degraded swamp forest, shrub land, and mixed agricultural land. Aboveground carbon stocks in each group was estimated by purposively assessing all carbon sources within 5-11 plots of 20 m x 100 m area. Belowground carbon was also measured on peatland. Results show that among the groups, the highest to the lowest order of aboveground carbon sink consecutively were low degraded swamp, low degraded lowland, low degraded peatland, high degraded swamp, high degraded peatland, high degraded lowland forests, mixed agricultural land, and shrub land (269.1 to 46.3 ton C/ha) plus other biomass sources recruited from belowground roots. It is demonstrated that forest degradation and land cover changes reduce amount of above ground carbon stocks and thus could result large amount of carbon loss from forests. Surprisingly, our results demonstrated that 0.5-5.2 m belowground carbon in peatland contribute to large amount of carbon Each meter depth of those fibrist to hemist peat sinked ~634 ton C/ha. It is estimated that the 22,600 ha area of overall forest types/ land covers sink ~2.5 million of aboveground and ~5,570 ha peatland area hold ~9.2 million of below ground carbon. This amount of carbon is potential sink of carbon yet could be a huge losses if peatland forest and land cover changes continued. Keywords: Aboveground carbon, belowground carbon stocks, degraded forest, land cover change, forest typesÂ

Steel is the main material used as reinforcement in reinforced concrete structures. Naturally, the number of steels used rapidly increase every year. The increase has an effect on the availability of steel’s main raw materials which is iron ore, a non-renewable natural resource. Therefore, an alternative steel replacement material is needed. Bamboo is chosen as an alternative substitute for reinforcing steel in reinforced concrete structures. In this study, petung bamboo caps anchored using screw nails was used as flexible reinforcement in reinforced concrete beams. This study aimed to analyze the behavior of load and deflection relationships in the flexural capacity of bamboo reinforced concrete beams against steel reinforced concrete beams. There were 6 beams used as specimens, consisting of 2 bamboo reinforced concrete beams with 1cm long screws, 2 bamboo reinforcing beams with 2 cm long screw nails, and 2 beams with 12 mm diameter steel reinforcement as a control beam. The results showed the flexural strength of bamboo reinforced concrete beams with 1 and cm hook length was 44.32 kN and 46.98 kN or 48.64% and 51.56 compared to steel reinforced concrete beams with flexural strength values of 91.10 kN.

didik untuk belajar bahasa Indonesia sekaligus mengembangkan sikap dan perilaku peduli terhadap lingkungan. Melalui metode dokumentasi, tulisan ini disajikan dengan tujuan memaparkan kompetensi pembelajaran bahasa Indonesia berbasis teks di SMP dan mendeskripsikan teks dengan muatan pendidikan lingkungan berbasis kearifan lokal Osing serta penggunaannya dalam pembelajaran. Hasil kajian menunjukkan bahwa terdapat teks bermuatan pendidikan ekologi yang dapat digunakan sebagai sumber materi pembelajaran beragam teks, seperti teks prosedur dan teks fabel. Dari teks-teks tersebut peserta didik, khususnya yang berlatar budaya Osing, dapat dibimbing dalam rangka menguasai kompetensi bahasa serta menumbuhkembangkan sikap dan perilaku peduli terhadap lingkungannya.