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"Concreteis a favoured building material due to its ease of productionand use. Even though the concrete mix isdesigned to have a uniform strength throughout the entire member, casting, aswell as the basic characteristics of the concrete materials, could yield anon-homogeneous constitution, resulting in a concrete strength gradation as afunction of the depth of the member. A functionally continuous and smooth strengthgradation of the concrete member along its axis or section is defined as gradedconcrete. The objective of this researchis to analyse the influence of two different concrete compressivestrengths that composed the gradedconcrete member. Thestudy is split into two parts: theexperimental work describing and identifying the mechanical properties offunctionally graded concrete and the finite element analysis implementing theseproperty variations in a model. The results showed that the concrete gradationinfluenced the ultimate strength of a member negatively and altered the stressdistribution and displacement response of the specimen."

"Concrete is a favoured building material due to its ease of production and use. Even though the concrete mix is designed to have a uniform strength throughout the entire member, casting, as well as the basic characteristics of the concrete materials, could yield a non-homogeneous constitution, resulting in a concrete strength gradation as a function of the depth of the member. A functionally continuous and smooth strength gradation of the concrete member along its axis or section is defined as graded concrete. The objective of this research is to analyse the influence of two different concrete compressive strengths that composed the graded concrete member. The study is split into two parts: the experimental work describing and identifying the mechanical properties of functionally graded concrete and the finite element analysis implementing these property variations in a model. The results showed that the concrete gradation influenced the ultimate strength of a member negatively and altered the stress distribution and displacement response of the specimen."

"It is widely use ofair-conditioning systems in Thailand due to its location. It is located in atropical zone with relatively high temperatures all year round, with highhumidity and high intensity of sunlight. In order to save electrical energy forair-conditioning systems, preventing heat transfer into the building isrequired. The objective of this study is to investigate the physical andthermal properties of concrete blocks. An attempt is made to increase heatresistance of concrete blocks. Foam beads (0-0.30% by weight) and kaolin (0-70% by weight) wereadded in concrete block mixture to increase discontinuous voids in concrete.Compressive strength and water absorption of concrete blocks were tested. Thetesting results indicated that compressive strength decreased when foam beadsand kaolin were added. Water absorption increased when foam beads were added.In contrast, the more kaolin added the less water absorption. The thermalconductivity coefficient of concrete blocks was also investigated. The resultsconfirmed that the higher the amount of foam beads or kaolin added, the higherthe thermal resistance of concrete blocks. Thermal time-lag behavior was alsoinvestigated. The results indicated that concrete block with kaolin took thelongest time in heating and took the shortest time in cooling. These propertiesare good for heat prevention in hot climate regions. These concrete blockswhich were developed and tested in this research conform to the Thai IndustrialStandard. Finally, it can be concluded that because of its thermal behavior,concrete block with kaolin is a suitable energy-saving concrete block for hotand humid climates."

"Nanostructured zincoxide (ZnO) was synthesized via a sonochemical method. The effect of the duration of ultrasonic irradiation in a continuous mode on the generated particles was investigated. Additionally, the effect of flowing either air or nitrogen during the sonication process was investigated. Zinc nitrate andammonia water-based solutions were selected as chemicals without the additionof other surfactants. The generated particles indicated that a wurtzitestructure of ZnO in a hexagonal phase was formed with a crystalline size that increasedas the ultrasound irradiation time increased. The morphology of the generatedZnO particles could be changed from flowerlike to needlelike structures viacontinuous ultrasound irradiation over one to two hours, resulting in increasesin the particle lengths and decreases in the particle diameters from 200 to 80nm. Photoluminescence intensity was also increased with increases in the ultrasonicirradiation times. Photoluminescence spectra were also influenced by theatmospheric environment. Two bands centered at 390 and 500 nm were generatedunder a nitrogen environment. On the other hand, a single wide band with a peakat around 430 nm was found for particles generated under an air environment. Itcan be applied for light emitting diodes (LED) or laser fabrication with acontrolled emitting band."

"Beton merupakan material getas dan lemah terhadap tarik dibandingkan baja. Salah satu solusi untuk mengatasi kelemahan beton adalah penambahan serat plastic jenis polypropylene dalam bentuk kemasan air minum pada material beton. Berangkat dari keberhasilan fiber reinforced concrete, maka dilakukan penelitian mengenai pengaruh penambahan cacahan limbah gelas plastik PP dalam meningkatkan kinerja beton. Tujuan penelitian ini adalah untuk mempelajari efektifitas penggunaan cacahan limbah plastik PP terhadap peningkatan kuat tekan dan kuat geser beton dengan fc? = 25 MPa, di samping itu untuk mengurangi penumpukan limbah gelas plastik minuman yang terus meningkat setiap tahun.Kadar cacahan polypropylene yang ditambahkan pada beton normal adalah 0,00 kg/m3 (0,00 %); 0,90 kg/m3 (0,10 %); 1,80 kg/m3 (0,20 %); 2,70 kg/m3 (0,30 %); 4,50 kg/m3 (0,50 %); 6,30 kg/m3 (0,70 %); 9,0 kg/m3 (1,00 %); 18,0 kg/m3 (2,00 %); 27,0 kg/m3 (3,00 %) untuk pengujian kuat tekan dengan umur benda uji 7 hari dan 28 hari, serta 0,00 kg/m3 (0,00 %); 0,90 kg/m3 (0,10 %); 1,80 kg/m3 (0,20 %); 2,70 kg/m3 (0,30 %); 4,50 kg/m3 (0,50 %); 6,30 kg/m3 (0,70 %); 9,0 kg/m3 (1,00 %) untuk pengujian kuat geser dengan umur benda uji 28 hari.Percobaan pembebanan yang dilakukan meliputi pembebanan untuk uji tekan beton, uji geser beton dan uji modulus elastisitas beton. Benda uji percobaan uji tekan dan uji modulus elastisitas beton adalah silinder dengan diameter 15 cm dan tinggi 30 cm. Benda uji percobaan uji geser beton adalah balok double ? L dengan ukuran ( 5 , 7 30 20 × × ) cm⊃³;.Penelitian dilaksanakan di Laboratorium Struktur dan Material Departemen Sipil Fakultas Teknik, Universitas Indonesia. Metode yang digunakan dalam penelitian ini adalah metode eksperimental. Hasil pengujian akan dibahas dengan analisa kuantitatif, analisa kualitatif dan analisa biaya. Metode pengujian untuk material dasar dan beton mengacu pada ASTM Standard, sedangkan untuk metode rancang campur beton berdasarkan U.S. Bureau of Reclamation.Dari hasil penelitian beton, dapat disimpulkan dengan bertambahnya kadar cacahan, cenderung adanya penurunan slump pada penambahan kadar cacahan lebih besar dari 0,30%. Dari hasil pengujian, pada penambahan kadar cacahan polypropylene 1,00% terjadi peningkatan kuat tekan 7 hari sebesar 5,000%. Sedangkan tidak ada peningkatan kuat tekan yang signifikan pada kuat tekan 28 hari. Pada penambahan kadar 0,50% peningkatan kuat geser 28 hari sebesar 42,647%.

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Concrete as construction material is known brittle material and has weak tensile strength, compared to steel material. Therefore, need an alternative solution to improve characteristics of the concrete. One of the alternative solution is by adding fiber polypropylene plastic waste on normal concrete.Based on the successful of fiber reinforced concrete, this research is done by adding crushed polypropylene plastic waste to improve characteristics of the concrete material. The object of this research is to learn the effect of usage polypropylene plastic waste in compressive and shear strength with fc? = 25 MPa, besides to decrease urban waste problem.The proportion of crushed polypropylene added to normal concrete are 0,00 kg/m3 (0,00 %); 0,90 kg/m3 (0,10 %); 1,80 kg/m3 (0,20 %); 2,70 kg/m3 (0,30 %); 4,50 kg/m3 (0,50 %); 6,30 kg/m3 (0,70 %); 9,0 kg/m3 (1,00 %); 18,0 kg/m3 (2,00 %); 27,0 kg/m3 (3,00 %) for compressive strength test on 7 days and 28 days, also 0,00 kg/m3 (0,00 %); 0,90 kg/m3 (0,10 %); 1,80 kg/m3 (0,20 %); 2,70 kg/m3 (0,30 %); 4,50 kg/m3 (0,50 %); 6,30 kg/m3 (0,70 %); 9,0 kg/m3 (1,00 %) for shear strength test on 28 days.The tests consist of compressive test, shear test and modulus of elasticity test. The specimen for compressive and modulus of elasticity test is cylinder with 15 cm diameter and 30 cm height. The specimen for shear test is double ? L beam with sizing ( 5 , 7 30 20 × × ) cm³.The research is done at Structure and Material Laboratory Civil Engineering Department, University of Indonesia. This research used experimental method. The result of experiment will analyze by quantitative analysis, qualitative analysis and cost analysis. Standard test method for raw material and concrete is based on ASTM Standard. Mix design method is based on U.S. Bureau of Reclamation. The result for slump test remain stable by adding crushed polypropylene plastic waste until 0,30%. After proportion of crushed polypropylene is higher than 0,30% added on normal concrete, slump value will decrease.From the compressive test on 7 days, there is 5,00% of compressive strength improvement by adding 1,00% of crushed polypropylene plastic waste on normal concrete. From the compressive test on 28 days, there is no significant result of compressive strength improvement. From the shear test on 28 days, there is 42,65% of shear strength improvement by adding 0,50% of crushed polypropylene plastic waste on normal concrete"

"Compositesof montmorillonite (MMT) - lithium salts have been prepared using a simple process of powders mixing followed by heating. The powders resulting from this method are expected to beionic conductors with a high ionic conductivity characteristics. This characteristics is also further improved by employing gamma-ray irradiation technique at specified irradiation doses. The best results were obtained for the (LiCl)0.5(MMT)0.5 composite with a room temperature ionic conductivity of 2.192 mS/cm, which then increases to ~5 mS/cm after gamma irradiation at a dose of 400 kGy. This value is equivalent to the value of the ionic conductivity of current commercial rechargeable lithium battery, which is ~10 mS/cm. However the commercial battery system is still employing an unsafe organic electrolyte. By employing this lightweight,inexpensive and high-temperature resistant ceramic montmorillonite, the final result of this Research and Development workt is expected to provide an alternative solid electrolyte system for rechargeable battery which is safer and more inexpensive especially for secondary battery technology development in Indonesia.

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Dampak Suhu Panas dan Iradiasi Sinar - - pada Konduktivitas Ion (LiCl)x(Montmorillonite)1-x. Pembuatan bahan elektrolit padat dilakukan dengan proses sederhana berupa pencampuran serbuk yang diikuti dengan pemanasan yang diharapkan dapat membentuk komposit montmorillonite (MMT)-garam Litium yang memiliki karakteristik konduktivitas ionik yang tinggi. Karakteristik ini juga dicoba ditingkatkan lebih jauh dengan menggunakan iradiasi sinar gamma dengan pengaturan dosis radiasi. Hasil terbaik diperoleh untuk komposit (LiCl)0.5(MMT)0.5 dengan nilai konduktivitas ionik pada suhu ruang mencapai 2,192 mS/cm yang meningkat menjadi ~5 mS/cm setelah iradiasi gamma dengan dosis 400 kGy. Nilai ini seorde dengan nilai konduktivitas ionik baterai isi ulang yang ada saat ini yang bernilai ~10 mS/cm namun masih menggunakan elektrolit organik yang kurang aman. Dengan penggunaan keramik montmorillonite yang ringan, murah serta memiliki kemampuan untuk bertahan pada kondisi suhu tinggi, hasil dari litbang ini diharapkan memberikan prospek salah satu alternatif sistem elektrolit padat baterai isi ulang yang aman dan ekonomis terutama untuk pengembangan teknologi baterai di Indonesia."

"Material merupakan komponen yang penting dalam menentukan besarnya biaya suatu proyek, lebih dari separuh biaya proyek diserap oleh material yang digunakan (Nugraha, 1985), Pada tahap pelaksanaan konstruksi penggunaan material di lapangan sering terjadi sisa material (waste) yang cukup besar, sehingga upaya untuk meminimalisasi sisa material penting untuk diterapkan.Tingkat waste material dapat dikendalikan tergantung dari kemampuan personil atau organisasi suatu proyek dimana masing-masing organisasi tentunya memiliki tingkat waste yang berbeda-beda. Bahkan dalam suatu organisasi, waste yang terjadi pada tiap sub organisasi dapat berbeda pula.Dengan melihat potensi yang cukup signifikan untuk mengendalikan sisa material maka dibuatlah suatu software untuk mengoptimasi nilai waste besi tulangan agar menjadi lebih optimal. Software ini pertama kali dicetuskan oleh Bapak Budi Suanda ST, MT dengan nama Software Optimasi Waste Besi (SOWB) . Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan aplikasi SOWB dalam mengoptimasi sisa material (waste) besi tulangan pada pekerjaan struktur beton bertulang.Metode penelitian yang dilakukan adalah dengan melakukan pendekatan kuantitatif berupa archival analysis ke lapangan yang digunakan untuk meneliti berapa besar nilai waste besi tulangan pada pekerjaan struktur beton bertulang yang dihasilkan.Penelitian ini dilakukan dengan cara menghitung nilai waste besi tulangan dengan dengan menggunakan aplikasi SOWB lalu mengoptimasi nilai waste besi tulangan tersebut menjadi lebih optimal dengan beberapa metode optimasi. Diharapkan dengan perhitungan tersebut dapat diketahui seberapa keberhasilan aplikasi SOWB dalam mengoptimasi sisa material (waste) besi tulangan pada pekerjaan struktur beton bertulang.

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Material represent important component in determining the level of the expense of a project, More than a half the expense of the project permeated by used material (Nugraha, 1985), At the execution phase of construction, usage of material often generating huge of waste material, so that optimize the waste material is important to be applied.Rate of waste material can be controlled depends on the ability of the organization or personnel project. Each organization have different rate of waste each other. Even in an organization, waste that happened at every sub organization can different each other.Seen potency which enough significant to control the waste of material hence made a software to optimize the reinforcement bar waste in order to become more optimal. This Software first time triggered by Mr. Budi Suanda ST, MT by the name of Software Optimasi Waste Besi (SOWB).This research aim to to know the influence of usage "SOWB" application in reinforcement bar waste optimization at reinforcement concrete structure work. Research method taken is by conducting quantitative approach in the form of analysis archival used to check how big reinforcement bar waste value at work of reinforcement concrete structure.This research is conducted by calculating reinforcement bar waste value by using SOWB application and then optimize the reinforcement bar waste become more optimal with a few method of optimization.Expected with the calculation we can discover the efficiency of application " SOWB" in reinforcement bar waste optimization."

"Pelumas mesin adalah zat kimia berbentuk cairan yang diberikan diantara dua benda yang bergerak untuk mengurangi gaya gesek yang terjadi. Pelumas mesin perlu diganti secara berkala untuk menjaga keawetan mesin kendaraan roda empat. Produsen pabrikan kendaraan roda empat sudah memberikan jangka waktu penggantian pelumas kepada konsumen, namun jangka waktu tersebut hanya berupa acuan. Tujuan dari penilitian ini adalah mempelajari metode perhitungan untuk menemukan waktu penggantian pelumas yang tepat beserta parameternya, mempelajari hubungan dan karakteristik antara temperatur pelumas mesin dengan temperatur coolant, serta mempelajari hubungan perilaku berkendara terhadap penurunan kondisi pelumas mesin. Penilitian ini dilakukan dengan mengambil data temperatur pelumas mesin dan coolant menggunakan Ancel kemudian dilakukan analisis untuk mendapatkan rumus penentuan temperatur pelumas mesin dan didapati mean absolute error sebesar 0 hingga 3,60. Penilitian ini dilakukan dengan melakukan pengujian perilaku berkendara eco, normal, dan sport sejauh 300 km tiap perilaku berkendara. Pada penelitian ini, data kecepatan putaran mesin dan temperatur coolant diambil melalui OBD II lalu diolah menggunakan Raspberry Pi menjadi RPS dan temperatur pelumas mesin kemudian diolah lebih lanjut oleh backend kemudian data tersebut dikirimkan ke Android. Pada aplikasi Android, output dari hasil pengolahan data tersebut ditampilkan menjadi persentase kondisi pelumas mesin, jarak sisa tempuh pelumas mesin, dan waktu sisa tempuh pelumas mesin. Hasil pengujian menunjukkan bahwa pada perilaku berkendara sport, kondisi pelumas mesin mengalami penurunan paling besar di angka 3,9% diikuti dengan normal sebesar 3,18% dan yang mengalami penurunan paling sedikit adalah eco dengan 2,39%.

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Engine oil is a liquid chemical that is given between two moving objects to reduce the frictional force that occurs. Engine lubricant needs to be replaced periodically to maintain the durability of four-wheeled vehicles. Manufacturers of four-wheeled vehicle manufacturers have given the lubricant replacement period to consumers, but this time period is only a reference. The purpose of this research is to study the calculation method to find the right time to replace the lubricant along with its parameters, study the relationship and characteristics between engine lubricant temperature with coolant temperature, and study the relationship of driving behavior to decrease engine lubricant conditions. This research was carried out by taking data on engine lubricant temperature and coolant using Ancel and then analyzing it to get the formula for determining engine oil temperature and found the mean absolute error of 0 to 3.60. This research is done by testing the driving behavior of eco, normal, and sport as far as 300 km for each driving behavior. In this study, engine speed and coolant temperature data are taken through OBD II and then processed using Raspberry Pi into RPS and engine lubricant temperature then further processed by the backend then the data is sent to Android. On the Android application, the output of the data processing results is displayed as a percentage of engine lubricant conditions, engine lubricant remaining distance, and engine lubricant remaining time. The test results show that in sports driving behavior, the condition of engine lubricants decreased the most at 3.9% followed by normal at 3.18% and the lowest decreased was eco with 2.39%."

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Penelitian ini membahas hubungan cepat rambat gelombang ultrasonik dengan kuat tekan dan pola retak beton daur ulang. Pengujian cepat rambat gelombang ultrasonik (UPV) dilakukan menggunakan PUNDIT. Pengamatan pola retak menggunakan metode digital image correlation (DIC). Benda uji yang dibuat adalah 16 kubus ukuran 15 cm dan 4 balok ukuran 15x15x50 cm. Spesimen kubus diuji tekan di umur 3, 7, 14, dan 28 hari dan di umur 28 disertai metode DIC. Pengujian metode DIC menggunakan kamera Fuji Film XA-3 dan diolah dengan software Ncorr pada MATLAB. Benda uji balok diuji UPV setiap jamnya di 24 jam pertama dan setiap hari sampai umur 28 hari. Penelitian ini menghasilkan hubungan logaritmik antara nilai UPV dan umur beton daur ulang dengan persamaan tiap benda uji sebagai berikut, VA = 2.68745E+02ln(x)+1.92197E+03, R2=0.809, VB = 2.75780E+02ln(x) + 1.82082E+03, VC = 3.51058E+02ln(x) + 1.59413E+03, dan VD = 3.51448E+02ln(x) + 1.61130E+03 dengan nilai R2 sebagai berikut, RA 2 =0.809, RB 2=0.844, RC 2=0.762, dan RD 2=0.772. Dihasilkan hubungan eksponensial antara kuat tekan beton dan nilai UPV dengan persamaan fc = 1.58593E01e1.22057E+00V[m/s] dengan nilai R2=7.36785E-01. Hasil pengujian metode DIC menunjukkan evolusi deformasi vertikal dan horizontal serta evolusi pola retak dari beton daur ulang. Stiffness tiap benda uji sebesar B = 862.92 kN/mm, C = 902.21 kN/mm, dan D = 1018.22 kN/mm. Poisson ratio dari benda uji sebesar B = 0.2478, C = 0.2302, dan D = 0.2392.

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This research will conduct a discussion about relationship between ultrasonic pulse velocity and compressive strength along with crack pattern of recycled concrete. Ultrasonic pulse velocity (UPV) will be measured using the PUNDIT. Observation of crack patterns using digital image correlation (DIC) method of recycled concrete. The specimens to be made are 16 cubes with dimension of 15cm and 4 beam with dimension of 15x15x50 cm. Cube specimens aged 3, 7, 14, and 28 days will be tested and on the day 28 will use DIC method. DIC method use Fuji Film XA-3 as to capture pictures which will be processed with Ncorr on MATLAB. Beam specimens will be used for UPV test within every hour in the first 24 hours and every day up to 28 days. This study results show logarithmic relationship between the UPV and the age of recycled concrete with the result equation each specimen as follows, VA = 2.68745E + 02ln (x) + 1.92197E + 03, VB = 2.75780E + 02ln (x ) + 1.82082E + 03, VC = 3.51058E + 02ln (x) + 1.59413E + 03, and VD = 3.51448E + 02ln (x) + 1.61130E + 03 with the coefficient of determination of each specimen as follows, RA2 = 0.809, RB2 = 0.844, RC2 = 0.762, and RD2 = 0.772. Exponential relationships shown between concrete compressive strength and UPV in equation of fc = 1.58593E01e1.22057E + 00V [m / s] with R2 = 7.36785E-01. The DIC test results show the evolution of vertical and horizontal deformations as well as the evolution of crack patterns of recycled concrete. Stiffness of each specimens as follows, B = 862.92 kN / mm, C = 902.21 kN / mm, and D = 1018.22 kN / mm. Poisson ratio of each specimens as follows B = 0.2478, C = 0.2302, and D = 0.2392.

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