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"The definition of the physical and mechanical properties of sugarcane trash pellets were necessary for the design considerations relating to storage, handling and processing equipment. The mixing ratios of ground sugarcane trash:cassava starch:water content (1.0:0.25:0.85 and 1.0:0.25:1.40 by weight) and pelleting speeds (100, 120, 140, and 160 rpm) were considered to determine their effects on bulk density, true density, porosity, durability and compressive strength. The results show that the mixing ratio by weight of 1.0:0.25:0.85 and pelleting speed of 120 to 140 rpm were optimum for producing the sugarcane trash pellets. At the moisture content of 12.01% (wb), the bulk density, true density, durability and compressive strength of biomass pellets were in the range of 330.93 to 365.00 kg/m3, 860.38 to 918.43 kg/m3, 99.34 to 99.46 % and 5.15 to 6.43 MPa, respectively."

"The definition of the physical and mechanicalproperties of sugarcane trash pellets were necessary for the designconsiderations relating to storage, handling andprocessing equipment. The mixing ratios of groundsugarcane trash:cassava starch:water content (1.0:0.25:0.85 and 1.0:0.25:1.40 by weight) and pelleting speeds (100, 120, 140, and 160 rpm) were considered to determine their effects on bulkdensity, true density, porosity, durability and compressive strength. The results show that the mixing ratio byweight of 1.0:0.25:0.85 and pelleting speed of 120to 140 rpm were optimum for producing the sugarcane trash pellets. At the moisture content of 12.01% (wb), the bulk density, true density, durability and compressive strengthof biomass pellets were in the range of 330.93 to 365.00 kg/m3, 860.38 to 918.43 kg/m3, 99.34 to 99.46 % and 5.15 to 6.43 MPa, respectively."

"The present study investigated the mechanical properties and microstructure of ultrafine grained (UFG) brass processed by four passes of equal channel angular pressing (ECAP) and annealed at elevated temperatures. The mechanical properties of all samples were assessed using tensile and micro-hardness tests. Microstructure analysis was performed using optical microscopy (OM) and scanning electron microscopy (SEM). Ultimate tensile strengths (UTS) and yield strengths (YS) of 878 and 804 MPa, respectively, ductility of 15%, and hardness of 248 HV were obtained for samples processed by four passes of ECAP with equivalent true strain of 4.20. Annealing at 300°C caused UTS and YS to decrease significantly, to 510 and 408 MPa, respectively, ductility to increase to 28%, and hardness to decrease to 165 HV. Fractography analysis of un-annealed samples after four ECAP passes showed small brittle fractures with shallow dimpling. Ductile failures were found on annealed samples. After four ECAP passes, the microstructure of un-annealed samples was UFG and dominated by lamellar grain with shear band. In contrast, after annealing, the microstructure changed due to recrystallization, showing nucleation and grain growth."

"In the present study, natural fibers located in thick outer woody rinds of the metroxylon sago (MS) tree were investigated. The investigation focused on measuring the mechanical properties and observing the microstructures of MS fibers before and after treatment with 5% sodium hydroxide. A scanning electron microscope was used to observe the microstructure of MS fiber, and the results showed that there was a decrease in fiber diameter after mercerization. A porous structure in the cross-section area of untreated fibers was clearly seen, and it was highly compressed after mercerization. The strength of MS fiber increased significantly after it was treated by 5% NaOH solution for two hours. The average ultimate strength of untreated MS fiber was recorded as 46 MPa; treatment with sodium hydroxide resulted in a significant increase in average ultimate strength to 163 MPa. Additionally, the elastic modulus of treated fiber was greater than that of untreated fiber."

"This work investigates the fresh, mechanical and durability properties of normal, Self-Compacting Concrete (SCC) and Smart Dynamic Concrete (SDC), which are a new generation of concrete with a lower amount of cementitious content. SDC is a low-fine, self-compacting concrete, that combines the benefits of normal concrete (stability) and self-compacting concrete (fresh properties). Fresh properties such as slump flow, L-box and V-funnel tests were investigated to evaluate its self-compacting properties. Mechanical properties such as compressive, splitting tensile and flexural strengths were also examined to compare its effectiveness with normal concrete. In addition to the fresh and hardened properties, the rapid chloride permeability test was also conducted to check the durability of normal, SCC and SDC concrete mixtures. The test results of the fresh properties clearly showed that SDC exhibited superior flowability in the slump flow, L-box and V-funnel tests within the limits of EFNARC (The European Federation of Specialist Construction Chemical and Concrete Systems) guidelines. The mechanical properties of SDC attained higher compressive strength, splitting tensile strength and flexural strength compared with the normal and SCC concrete mixtures. The rapid chloride permeability tests result of SDC clearly showed that SDC exhibited similar and better results than that of normal and SCC concrete mixtures."

"Penelitian ini bertujuan untuk mengetahui pengaruh kandungan nikel dalam elektroda terhadap sifat mekanis dan mikrostruktur pengelasan baja pelat SM570TMC dan AH36. Pengelasan material tersebut menggunakan metode Flux Cored Arc Welding (FCAW) dengan kawat las yang memiliki kandungan nikel 0%, 1%, dan 1,5%. Hasil dari pengelasan diteliti dengan pengujian tak rusak (MPT, UT) dan rusak (Hardness Vickers, impact charpy, pengamatan mikrografi (makro, mikro, SEM, EDS, OES)). Pengujian dilakukan pada area base metal (BM), Heat Affected Zone (HAZ) dan Weld Metal (WM). Pengujian impact charpy dilakukan pada temperatur 25⁰C, 0⁰C, dan -20⁰C. Pengujian NDT tidak mempengaruhi kualitas lasan. Hasil pengujian kekerasan pada penambahan 1% nikel material AH36 maksimum sebesar 190 HV dan minimum 163 HV sedangkan untuk material SM570TMC maksimum sebesar 172 HV dan minimum 154 HV. Material AH36 mempunyai nilai ketangguhan impak pada temperatur 0⁰C sebesar 280 J dan pada temperatur-20⁰C sebesar 200 J diarea HAZ. Material SM570TMC nilai ketangguhan impak sebesar 385 J pada temperatur 0⁰C dan 276 J pada temperatur -20⁰C diarea HAZ. Dengan penambahan 1% nikel menunjukkan dalam pengamatan mikro menghasilkan butiran yang lebih halus bila dibandingkan penambahan nikel 0 dan 1,5% sehingga mampu meningkatkan nilai ketangguhannya pada material AH36 dan SM570TMC terutama pada temperatur 0⁰Cdan -20⁰C.

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This study aims to determine the effect of nickel content in electrodes on the mechanical and microstructure properties of welding steel plates SM570TMC and AH36. Welding of the material uses the method of Flux Cored Arc Welding (FCAW) with welding wire which has a nickel content of 0%, 1%, and 1.5%. The results of welding were examined by non-destructive testing (MPT, UT) and damaged (Vickers Hardness, charpy impact, micrographic observations (macro, micro, SEM, EDS, OES)). Tests were carried out on the base metal area (BM), Heat Affected Zone (HAZ) and Weld Metal (WM). Charpy impact testing is carried out at temperatures of 250C, 00C, and -200C. NDT testing does not affect weld quality. The hardness test results on the addition of 1% nickel AH36 material to a maximum of 190 HV and a minimum of 163 HV while the SM570TMC material is a maximum of 172 HV and a minimum of 154 HV. AH36 material has an impact toughness value at a temperature of 0⁰C of 280 J and at a temperature of -20⁰C of 200 J at HAZ area. Material of SM570TMC impact resistance value was 385 J at temperatures of 0⁰C and 276 J at -20⁰C at HAZ. With the addition of 1% nickel, the micro-observation produced finer grains when compared to the addition of 0 and 1.5% nickel so as to increase the toughness value of AH36 and SM570TMC materials, especially at temperatures of 0⁰C and -20⁰C."

"ABSTRAKKekerasan fisik pada anak dapat diwujudkan dalam berbagai bentuk. Salah satu yang banyak dilakukan adalah memukul anak sebagai bentuk hukuman akan kesalahan anak. Kekerasan fisik pada anak dapat menimbulkan berbagai dampak antara lain gangguan depresi, gangguan kecemasan, kepercayaan diri yang kurang, dan kemungkinan perilaku berisiko di masa selanjutnya. Berbagai macam dampak ini dikhawatirkan akan berpengaruh terhadap prestasi belajar. Akan tetapi, penelitian di Indoensia mengenai hubungan kekerasan fisik terhadap prestasi belajar masih belum banyak dilakukan. Tujuan dari penelitian ini adalah untuk mengetahui hubungan riwayat kekerasan fisik terhadap prestasi belajar siswa Sekolah Menengah Atas di Kecamatan Beji, Depok. Penelitian ini menggunakan desain studi cross sectional. Data kekerasan fisik diambil melalui kuisioner Childhood Trauma Questionnaire, sedangkan data mengenai prestasi belajar diambil melalui pengumpulan nilai rapor 209 subjek yang merupakan siswa dari SMAN 11 Depok, SMA IT Al Qudwah, SMA Muhammadiyah Beji dan SMA Tarbiyah Islamiyah. Childhood Trauma Questionnaire memiliki sensitivitas 38 dan spesifisitas 80 dalam mendeteksi kekerasan fisik. Dari 209 subjek penelitian, 36 siswa mengalami kekerasan fisik dimana 19 siswa diantaranya memiliki prestasi belajar di bawah rata-rata. Pada kelompok yang tidak mengalami kekerasan fisik, 90 siswa memiliki prestasi belajar di bawah rata-rata dan 83 sisanya memiliki prestasi belajar di atas rata-rata. Hasil uji Chi-Square hubungan kekerasan fisik terhadap prestasi belajar memeberikan hasil nilai p = 0,934 dengan RR = 1,015 95 CI 0,72-1,43 . Hal ini menunjukkan bahwa tidak terdapat hubungan yang bermakna secara statistik antara riwayat kekerasan fisik terhadap prestasi belajar.

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ABSTRACTPhysical abuse in children can be manifested in various forms. One of the most common is to hit children as a form of punishment for children 39 s mistakes. Physical abuse in children can cause various effects. These kinds of impacts will affect the child 39 s growth and development, including social functions such as academic performance. However, research in Indonesia regarding the relationship of physical abuse to academic performance is still not widely practiced. The purpose of this research is to know the relationship of history of physical abuse to high school student rsquo s academic performance in Beji, Depok. This study used cross sectional study design. The data of physical violence was taken through the questionnaire of Childhood Trauma Questionnaire, while the data on academic performance was taken through the collection of 209 report cards which were students from SMAN 11 Depok, Al Qudwah IT Senior High School, SMA Muhammadiyah Beji and SMA Tarbiyah Islamiyah. Childhood Trauma Questionnaire has a sensitivity of 38 and a specificity of 80 on detecting physical abuse. Of the 209 study subjects, 36 students experienced physical abuse. Of the 36 students who experienced physical abuse, 19 students had below average learning achievement. While 17 others have above average learning achievement. In the non violent group, 90 students had below average learning achievement and the remaining 83 students had above average learning achievement. Result of Chi Square test of physical abuse relation to academic performance gives result p value 0,934 with RR 1,015 95 CI 0,72 1,43 . This shows that there is no statistically significant relationship between the history of physical abuse to the academic performance. This study can illustrate that physical abuse is not a single risk factor for under average learning achievement."

"Penelitian ini bertujuan untuk menguji pengaruh factor-factor agensi dan biaya transaksi terhadap rasio pembayaran dividen di Indonesia.Penelitian ini mencoba mendifinisikan mekanisme yang sesuai untuk mengurangi biaya agensi dan biaya transaksi yang ditunjukkan oleh kebijakan rasio pembayaran dividen...."

"Untuk mengetahui pengaruh Cu dan Zn terhadap paduan Al-Si-Mg maka dibuat Sampel I dan Sampel II. Sampel I paduan Al-Si-Mg dengan variasi persen berat (%wt) Cu sebesar : 0 ; 1,5 ; 3 dan 5 %wt sedang Zn dibuat konstan sebesar 1 %wt. Sampel II paduan Al-Si-Mg dengan variasi persen berat Zn sebesar : 0 ; 0,5 dan 1,5 %wt, sedang Cu dibuat konstan sebesar 3 %wt.Selanjutnya dilakukan pengujian terhadap sampel-sampel tersebut, yaitu, pengujian : kekerasan, titik leleh , foto struktur mikro , SEM-EDAX dan Meping. Disamping itu juga didukung oleh data sekunder yang berupa hasil pengujian kekuatan tarik dan hasil pengujian dengan XRD.Hasil pengujian menunjukkan bahwa : semakin besar kandungan Cu , maka kekerasan akan naik, titik leleh akan turun, sedang kekuatan tariknya mula-mula naik sampai dengan kandungan Cu = 3 %wt, kemudian turun sampai kandungan Cu = 5 %wt. Disamping itu juga ditunjukkan bahwa : semakin besar kandungan Zn , maka kekerasan dan titik leleh akan turun, sedang kekuatan tariknya mula-mula turun sampai kandungan Cu = 0,5 %wt, kemudian naik sampai kandungan Cu sebesar 1,5 %wt.Hasil pengujian-pengujian tersebut menunjukkan bahwa : pada paduan tersebut muncul dua fasa yang dominan, yaitu fasa yang sangat kaya dengan Al (sebagai matrik) dan fasa yang kaya dengan Si. Disamping itu juga menunjukkan bahwa Cu dan Zn sangat mempengaruhi bentuk morfologi dari struktur mikro paduan. Morfologi struktur mikro yang fasa kaya Si-nya berbentuk serabut yang berserakan (tidak teratur) mempunyai kekuatan tarik yang relatif tinggi."

"A mechanical assembly consists of several components to perform an intended function. At the design stage, the intended function must be converted into critical product dimensions. After determining the dimensions, a designer must determine the assembly tolerance and allocate this tolerance to the tolerances of the corresponding components. After determining the optimal tolerances, process selection must be conducted along with production allocation to the selected process. There are three aspects in commercial competition that must be considered by a manufacturing company: cost, quality, and delivery. The aim of this research is to develop an optimization model for process selection for a make to order company to minimize manufacturing cost, quality loss, and lateness cost. The model attempts to determine optimal tolerance and production allocation, which takes into consideration the production capacity and process sequence. Hence, the model attempts to include not only the product design decision, but also to solve the process selection and allocation problems. A numerical example is provided to show the implementation of the model."