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"Penelitian ini bertujuan untuk mengetahui pengaruh suhu rendah terhadap stabilitas warna material restoratif estetik sewarna gigi untuk keperluan forensik. Spesimen terdiri dari resin-modified glass ionomer cement (RMGIC) dan resin komposit giomer bulk-fill dipaparkan pada suhu 5,5-6,2ºC dan kelembaban relatif 20% dengan lama pemaparan 3, 7, dan 14 hari. Pengukuran warna spesimen sebelum dan sesudah perlakuan dilakukan menggunakan colorimeter. Hasil menunjukkan bahwa terdapat perbedaan bermakna pada setiap kelompok perlakuan pada hari ke-3, ke-7, dan ke-14 (p<0,05). Selain itu, terdapat perbedaan yang tidak bermakna antara kelompok RMGIC yang memiliki lama pemaparan 3 hari dengan lama pemaparan 7 hari (p>0,05) serta perbedaan yang bermakna (p<0,05) antara kelompok RMGIC yang dipaparkan selama 3 hari dengan 14 hari dan 7 dengan 14 hari; serta antara kelompok resin komposit giomer bulk-fill dengan lama pemaparan 3, 7, dan 14 hari. Perbedaan yang bermakna (p<0,05) juga ditemukan ketika kedua bahan dibandingkan dengan lama pemaparan yang sama (3, 7, dan 14 hari). Disimpulkan bahwa suhu rendah dapat mempengaruhi nilai perubahan warna RMGIC dan resin komposit giomer bulk-fill yang memiliki potensi untuk digunakan dalam keperluan odontologi forensik.

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The aim of this study was to analyze the effects of low temperature on the color stability of tooth-colored esthetic restorative materials for forensic purposes. Specimens consisted of resin-modified glass ionomer cement (RMGIC) and giomer bulk-fill composite resin that were exposed to the temperature of 5,5-6,2ºC and 20% relative humidity for 3, 7, and 14 days of exposure. Color measurement of specimens was done using colorimeter prior to and after the exposure of low temperature. The results showed that there were significant differences among each group of 3, 7, and 14 days exposure (p<0.05). In addition, there was an insignificant difference (p>0.05) between the group of RMGIC that was exposed to low temperature for 3 days and the group of RMGIC that was exposed for 7 days; significant differences (p<0.05) between the group of RMGIC that was exposed for 3 days and 14 days; 7 and 14 days; and among the groups of giomer bulk-fill composite resin that were exposed to low temperature for 3, 7, and 14 days. Significant differences (p<0.05) were also found when the two materials were compared under the same time of exposure (3, 7, and 14 days). It could be concluded that low temperature was capable of affecting the color change value of RMGIC and giomer bulk-fill composite resin, and therefore possessed a potential to be utilized for forensic odontology purposes."

"ABSTRAKPermintaan bahan bakar dan energi terus meningkat. Biodiesel adalah metil atau etil ester asam lemak dari minyak nabati maupun hewani yang banyak digunakan sebagai bahan bakar alternatif. Biodiesel umumnya diproduksi melalui transesterifikasi lemak ber-alkohol monohidrat rantai-pendek. Biodiesel dicampur dengan petroleum diesel untuk meningkatkan sifat fisikokimia yang berhubungan dengan CFP-nya. Proses produksi biodiesel dapat menyisakan SMG saturated monoglyceride . SMG dapat menyebabkan presipitasi di atas CP masing-masing komponen dalam campuran biodiesel petroleum diesel. Penelitian ini bertujuan untuk mengetahui pengaruh kandungan monogliserida dalam B100 pembentukan presipitat dalam BXX pada kondisi sebenarnya dengan modifikasi metode CSFT ASTM D7501 melalui beaker test dan modifikasi metode FBT ASTM D2068 melalui rig test. Presipitat dianalisis dengan GC, presipitat sebagian besar berupa monogliserida >60 yang tidak larut dalam PE dan berupa padatan pada suhu ruang 30oC . Secara umum semakin banyak monogliserida semakin banyak presipitat terbentuk. Pengaruh suhu terhadap kandungan monogliserida dan jenis monogliserida berbeda-beda, hal ini disebabkan kelarutan monogliserida solut sangat dipengaruhi persentase biodiesel dan petroleum diesel dalam campuran. Dengan mengintegrasikan hasil beaker test dan rig test didapatkan suatu model untuk memperkirakan FBT campuran.

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ABSTRACTFuel and energy demand keep increasing. Biodiesel is a methyl or ethyl ester of fatty acids from vegetable oils and animals that are widely used as alternative fuels. Biodiesel is generally produced by transesterification of short chain monohydric alcohols. Biodiesel is mixed with petroleum diesel to improve the physicochemical properties associated with its CFP. Biodiesel production process can leave SMG saturated monoglyceride . SMG can cause precipitation above each components rsquo CP in the biodiesel petroleum diesel blend. This study aims to determine the effect of monoglyceride content in B100 to the precipitate formation of BXX under actual conditions by modification of ASTM D7501 CSFT method through beaker test and modification of ASTM D2068 FBT method through rig test. The precipitates are analyzed by GC, the precipitate is mostly monoglyceride 60 which is insoluble in PE and is a solid at room temperature 30 C . In general, the increase in monoglycerides increases the precipitate formed. The influence of temperature on monoglyceride content and monoglyceride type varies, this is due to the solubility of monoglyceride solute which is greatly influenced by the percentage of biodiesel and petroleum diesel in the mixture. By integrating beaker test and rig test results, we obtained a model to estimate the FBT of the mixture."

"This thesis presents an experimental and theoretical study of the coherent properties of trapped atomic ensembles at high densities, which are essential to many of the aforementioned applications. The study focuses on how inter-particle interactions modify the ensemble coherence dynamics, and whether it is possible to extend the coherence time by means of external control. The thesis presents a theoretical model which explains the effect of elastic collision of the coherence dynamics and then reports on experiments which test this model successfully in the lab. Furthermore, the work includes the first implementation of dynamical decoupling with ultra-cold atomic ensembles. It is demonstrated experimentally that by using dynamical decoupling the coherence time can be extended 20-fold. This has a great potential to increase the usefulness of these ensembles for quantum computation."

"Polymer blends offer properties not easily obtained through the use of a single polymer, including the ability to withstand high temperatures. High temperature polymer blends outlines the characteristics, developments, and use of high temperature polymer blends.The first chapter introduces high temperature polymer blends, their general principles, and thermodynamics. Further chapters go on to deal with the characterization of high temperature polymer blends for specific uses, such as fuel cells and aerospace applications. The book discusses different types of high temperature polymer blends, including liquid crystal polymers, polysulfones, and polybenzimidazole polymer blends and their commercial applications.High temperature polymer blends provides a key reference for material scientists, polymer scientists, chemists, and plastic engineers, as well as academics in these fields."

"Helium Cryogenics, 2nd edition brings these advances in helium cryogenics together in an updated form. As in the original edition, the author's approach is to survey the field of cryogenics with emphasis on helium fluids. This approach is more specialized and fundamental than that contained in other cryogenics books, which treat the associated range of cryogenic fluids. As a result, the level of treatment is more advanced and assumes a certain knowledge of fundamental engineering and physics principles, including some quantum mechanics. The goal throughout the work is to bridge the gap between the physics and engineering aspects of helium fluids to provide a source for engineers and scientists to enhance their usefulness in low-temperature systems."

"Tesis desain ini membahas tentang pembentukan sebuah ruang arsitektur yang dihasilkan dari memahami respon inderawi yang dihasilkan dari seseorang yang memiliki keterbatasan visual (low vision) yang berproses memahami ruang secara bertahap. Proses terbentuknya sebuah ruang diturunkan dari pendekatan bagaimana seorang penderita low vision bergerak dan beraktifitas dalam lingkungannya. Riset ini dilakukan menggunakan tiga metode berbeda, yaitu yang pertama mengamati pengalaman visual dalam mengapresiasi media film, yang kedua memahami aktifitas keseharian di dalam ruang diri yang sudah dikenali, dan yang ketiga adalah memahami ruang diri yang baru pertama kali dialami.Pendekatan narasi yang terbentuk dalam memahami ruang menghasilkan beberapa proposisi penting yaitu penggunaan karakter ruang dengan warna-warna kontras, metode berjalan dan berhenti untuk melakukan reorientasi posisi, pengabaian aspek detail dan pengutamaan aspek fungsional, dan faktor-faktor pendukung lainnya. Low vision dalam kondisi yang sangat umum, terjadi tidak hanya pada satu kelompok differently-able saja, tetapi dapat digeneralisasi terjadi juga pada generasi lanjut usia (elderly).Pendekatan arsitektural berbasis narasi ini diterapkan dalam desain sebuah fasilitas publik untuk kelompok lanjut usia (elderly). Kecenderungan kenaikan jumlah penduduk lanjut usia dalam komposisi penduduk suatu kota menunjukkan pentingnya perhatian khusus terhadap eksistensi mereka dalam ruang publik. Mengakomodasi kebutuhan mereka secara arsitektural menjadi sangat perlu agar mereka sebagai kelompok yang memiliki keterbatasan secara visual mampu bergerak dan beraktifitas secara mandiri dalam ruang hidupnya.

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This design thesis develops a method of forming an architectural space generated from the understanding of the sensory response of a person with visual limitations (low vision) in the process of understanding the space gradually. The process of space formation is derived from how a person with low vision moves and conducts activities in the environment. The research was conducted through three different methods, the first one is observing the visual experience with the film as a media, the second one is understanding the spatial experiences in the daily activities within familiar space, and the third one is understanding the spatial experiences in non-familiar space.

The resulting narrative approach produced several important propositions, namely the use of spatial qualities with contrasting colors, the method of moving, walking and stopping to reorient the position, ignored details and enhanced functional aspects, and other supporting factors. Low vision in a very common condition, occurs not only in a differently-able group, but it can also generally occurs in the elderly group.

This narrative-based architectural approach is then applied in the design of a public facility for the elderly. The increasing tendency in the number of elderly in the urban population suggests the importance of special attention to their existence in public space. Architecture that could accommodate the spatial needs of people with visual limitations become necessary to enable them to move and to experience their life space independently."

"Roket adalah kendaraan peluncur yang mampu mengangkut muatan ke tujuan yang diinginkan. Nosel merupakan komponen struktural terberat, yaitu menyumbang sekitar 30 % dari berat keseluruhan struktur roket sehingga sangat terbuka kemungkinan untuk mereduksi beratnya, dalam mendesain nosel juga harus memperhatikan beban mekanik dan termal yang cukup tinggi akibat dari pembakaran propelan untuk menghasilkan gaya dorong (thrust) roket. Salah satu alternatif untuk mereduksi berat adalah penggunaan material Komposit Polimer Berpenguat Serat Karbon, untuk mengaplikasikan material komposit tersebut terhadap nozzle case, perlu dilakukan karakterisasi sifat-sifat mekanik. Salah satu pengujian yang paling sering dilakukan yaitu uji tarik (tensile test), pengujian ini memiliki fungsi untuk mendapatkan nilai kekuatan, modulus elastisitas, dan failure mode. Pengujian Tarik dilakukan melalui dua tahapan untuk menyeleksi material yang mampu menerima beban termal. Pengujian tarik tahap pertama dilakukan dengan rentang temperatur dari RT sampai 200°C menggunakan mesin Shimadzu AG-50KNX PLUS Machine untuk seleksi material antara komposit C/LY5052 dengan C/ARMC berdasarkan ketangguhan pada temperature yang diuji. Selanjutnya material yang terpilih diteruskan ke pengujian tahap dua, dimana material terpilih di uji Tarik pada rentang temperatur RT sampai 800°C dengan interval 100°C menggunakan mesin SCHENK TREBEL Machine. Hasil yang didapatkan pada penelitian ini, untuk gangguan mekanik pada nozzle case maksimum sebesar 7 MPa, beban mekanik ini sangat kecil jika dibandingkan dengan kekuatan tarik yang dimiliki komposit C/LY5052 dan C/ARMC, untuk beban termal pada Nozzle Case, pemanasan maksimum yang terjadi pada nozzle Case dengan rentang temperature 550ºC hingga 700°C, pada temperatur ini komposit C/LY5052 tidak bisa diterapkan karena hanya mampu bertahan sampai temperatur 200 ºC, hasil berbeda pada komposit C/ARMC pada saat rentang temperatur ini masih tangguh, maka dari hasil tersebut komposit C/ARMC dalam penelitian ini dapat dijadikan acuan sebagai alternatif material Nozzle Case. Namun ketika mendesain nozzle case dengan material komposit C/ARMC harus diperhatikan mode kegagalannya terutama mode kegagalan delaminasi.

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A rocket is a launch vehicle capable of transporting payload to the desired destination. The nozzle is the heaviest structural component, which contributes about 30% of the total weight of the rocket structure so it is very possible to reduce the weight. In designing the nozzle, one must also pay attention to the mechanical and thermal loads that are quite high due to the combustion of the propellant to produce rocket thrust. One alternative to reduce weight is the use of Carbon Fiber Reinforced Polymer Composite materials, to apply these composite materials to the nozzle case, it is necessary to characterize the mechanical properties. One of the most frequently performed tests is the tensile test. This test has a function to obtain values for strength, modulus of elasticity, and failure mode. Tensile testing is carried out in two stages to select materials that are capable of receiving thermal loads. The first stage of the tensile test was carried out with a temperature range from RT to 200°C using the Shimadzu AG-50KNX PLUS Machine for material selection between C/LY5052 and C/ARMC composites based on toughness at the temperature tested. Then the selected material is continued to the second stage of testing, where the selected material is tested in Tensile at a temperature range of RT to 800°C with intervals of 100°C using the SCHENK TREBEL Machine. The results obtained in this study, for maximum mechanical disturbance in the nozzle case of 7 MPa, this mechanical load is very small when compared to the tensile strength of the C/LY5052 and C/ARMC composites, for the thermal load on the Nozzle Case, the maximum heating that occurs on the Case nozzle with a temperature range of 550ºC to 700°C, at this temperature the C/LY5052 composite cannot be applied because it can only survive up to a temperature of 200 ºC, the results are different for the C/ARMC composite when this temperature range is still tough, so from these results, The C/ARMC composite in this study can be used as a reference as an alternative nozzle case material. However, when designing the nozzle case with C/ARMC composite material, the failure mode must be considered, especially the delamination failure mode."