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"Penelitian ini dilakukan untuk mengetahui pengaruh variasi jumlah lapisan kevlar dan impregnasi nano alumina pada serat kevlar terhadap ketahanan balistik komposit laminat hybrid. Terdapat beberapa bahan yang digunakan diantaranya adalah lembaran alumunium 2024-T3, serat kevlar berjenis 29, nano alumina serta resin epoksi.Dalam membuat larutan pengimpregnasi, bahan yang digunakan ialah larutan Polietilen glikol-400 yang kemudian dicampur dengan nano alumina dengan menggunakan magnetic stirrer selama 2 jam. Untuk menurunkan tegangan dan mengoptimalkan proses impregnasi pada serat kevlar, juga digunakan larutan etanol pada campuran larutan impregnasi. Setelah itu serat kevlar direndam dengan campuran yang sudah dibuat lalu dikeringkan. Langkah selanjutnya ialah merakit struktur komposit laminat dengan metode hand layup dengan bantuan epoksi sebagai perekat dan dilanjutkan dengan proses pengeringan di temperatur ruang dengan bantuan epoksi. Hasil percobaan menunjukkan bahwa penambahan jumlah lapisan sangat berpengaruh kepada ketahanan sampel dalam uji balistik maupun impak.Pengaruh dari variasi lapisan dan impregnasi nano alumina dapat meningkatkan ketahan balistik dan impak dari sampel.Hal ini dianalisis berdasarkan beberapa pengujian seperti pengamatan visual dan foto makro. Di sisi lain pengujian ketahan balistik juga diikuti dengan pengukuran diameter perforasi sekaligus tingkat kedalaman penetrasi yang dibentuk akibat proyektil.

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The goals of this research is to determine the effect of variations in the number of kevlar layers and nano alumina impregnation on kevlar fibres on the ballistic resistance of hybrid laminate composites. There are several materials used; aluminium sheet 2024-T3, kevlar fibre type 29, nano alumina and epoxy resin. In the process of making the impregnation solution, the component that used is Polyethylene glycol-400 solution, who will be mixing with nano alumina using a magnetic stirrer for 2 hours. For optimize the impregnation process in kevlar fibres and reduce the stress, ethanol solution was giving in a mixture of impregnation solution. After the Kevlar layers soaked in a solution, then the kevlar must be dried. The next step is to assemble the laminate composite structure by hand layup method with epoxy resin as an adhesive, and then by drying at room temperature. The experimental results show that increasing the number of layers and adding alumina particle on Kevlar fiber increases the effect of sample durability on ballistic tests and impacts. Those were analyzed based on several assessments; visual observations and macro photographs. On the other hand, ballistic endurance testing is also measured based on the size of the perforation diameter and the depth of penetration formed by the projectile."

"Penelitian pada tesis ini di bidang divais fotonik diutamakan pada pabrikasi dan karakterisasi dari bahan dasar GaInAsP/InP untuk penguat optik dengan panjang gelombang 1,55 µm, yang tidak lain adalah sama dengan bahan dasar untuk laser semikonduktor.Pada rancang bangun penguat optik dibuat struktur lapisan yang menghasilkan moda tunggal yang terdiri dan 4 buah lapisan GaInAsP, masing-masing 2 lapisan pandu gelombang dengan panjang gelombang 1,17 pm, lapisan aktif dengan 1,55 pm, dan lapisan anti cair ulang (ACU) dengan 1,3 gm. Untuk penumbuhan dipilih lapisan pandu gelombang dengan ketebalan 0,25 gm, lapisan aktif 0,19 pm dan lapisan ACU 0,19 gm. Di tumbuhankan dengan menggunakan LPE (Liquid Phase Epitaxy) yaitu penumbuhan yang dilakukan pada saat kristal dalam keadaan fasa cair dengan teknik penumbuhan Two-Phase Solution. Bahan InP, GaAs, InAs sebagai bahan sumber ditumbuhkan diatas substrat InP, membentuk struktur lapisan DH (Double Heterostructure) instrinsik tujuh lapisan dan melalui proses lanjutan dapat dibuat menjadi penguat optik atau diode laser sernikonduktor GaInAsP/InP 1,55 µm.Struktur dasar GaInAsP/InP untuk penguat optik dibuat dengan proses penumbuhan, yang dimulai dengan menyentuhkan larutan kristal Indium pada sampel substrat, kemudian dilakukan penumbuhan lapian dengan menyentuhkan larutan kristal secara berurutan diatas sampel substrat. Proses penumbuhan dilakukan tiga tahapan, yaitu : tahapan pendahuluan, tahapan pembentukan pandu gelombang dan tahapan pembentukan struktur DH (Double Heterostucture). Ketebalan lapisan dapat diatur dengan memvariasi suhu peleburan dan waktu penumbuhan. Karakterisasi ketebalan lapisan dilakukan dengan menggunakan SEM, dan Pengukuran panjang gelombang dilakukan dengan photoluminescence, dengan cara menembakkan laser pada pennukaan sampel. Emisi pandu gelombang diterima, direkam menggunakan optical spectrum analyzer (OSA).

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This research is focused on photonic devices particularly on fabrication and characteristic of 1.55 gm GaInAsP/InP semiconductor laser materials for an optical amplifier.

The Optical amplifier was designed for a single-mode laser. This layers contains of four layers where two of them ar ,used as 1,17 p.m wave guide and the other are applied as a 1,55 µm active layer and a 1,3 gm anti melt back (AMB) layer. The layers were growth by designing 0.25 gm wave guiding layer thickness, 0,19 gm active layer thickness, and 0.19 gm AMB layer thickness. The layers was grow by LPE (Liquid Phase Epitaxy) with The Two Phase Solution growing technique. Source material InP, GaAs, InAs was grown on InP substrate, form seven layers of intrinsic DH and then via further process, these layers structure ca be made as an optical amplifier or a semiconductor laser diode of 1.55 gm GaInAsPfInP .

The basic structure was made by touching an indium crystal on a sample substrate. Then , some layers were growth by touching other crystal solution consecutively on the sample substrate. The growth process was three step of growth i.e: in the first place of growth, growth of wave guide and growth of DH. The thickness of any layers was arranged by varying the melting temperature and the growth time. The thickness characterization of the layer was carried out by SEM and the wave length measurement was executed by shooting a laser on the sample surface. The emission of the wave guides was received and recorded by an optical spectrum analyzer."

"PENYELIDIKAN STRUKTUR DAN KARAKTERISTIK TANAH UNTUK DESAIN PONDASIIRADIATOR GAMMA KAPASITAS 2 MCi. Penyelidikan tanah telah dilakukan sebelum pekerjaandisain struktur pondasi gedung iradiator. Pengambilan sample ditetapkan di beberapa titik bor di sitefasilitas Iradiator pada lapisan tanah terganggu maupun tidak terganggu. Dari hasil penyelidikantanah ini akan dipilih alternatif / jenis, kedalaman serta dimensi pondasi yang paling ekonomis tetapimasih aman. Metode penyelidikan tanah yang digunakan adalah Deep Boring, Undisturbed danDisturbed Sampling, SPT (Standar Penetration Test), CPT (Cone PenetrationTest/Sondir). Pengetesan dilakukan di lapangan dan di laboratorium mekanika tanah untukmengetahui sifat mekanik, ketebalan lapisan tanah dan sifat-sifat fisis lainnya guna perhitungan dayadukung pondasi. Hasil penyelidikan tanah di tiga titik bor didapatkan hasil rata-rata kedalaman tanahkeras -19,33 m dan daya lekat 3163,88 kg/cm?. Uji boring pada salah satu titik ditemukan lapisantanah keras pada kedalaman 32 m dengan nilai SPT maksimal 16. Maka dari data dapat ditentukanjenis pondasi yang sesuai adalah bored pile. Dikarenakan pondasi merupakan penopang strukturatas yang dapat mengakibatkan penurunan/ settlement jika daya dukungnya tidak mampu menahanbeban di atasnya.INVESTIGATION OF STRUCTURE AND CHARACTERISTICS OF SOIL FOR FOUNDATIONDESIGN OF GAMMA IRRADIATORS CAPACITY 2 MCi. Soil investigation conducted before thework of irradiator building structural foundation design is initiated. Intake of sample was set at somepoint drill at Iradiator facility site to the disturbed soil layer or not disturbed. From the results of thissoil investigation will be selected as alternative / types, the depth and dimensions of the foundationof the most economical but still safe. Soil investigation method used was Deep Boring, undisturbedand disturbed sampling, SPT ( Standard Penetration Test ), CPT ( Cone Penetration Test / Sondir ).Testing conducted in the field and in the laboratory of soil mechanics to determine the mechanicalproperties, soil layer thickness and other physical properties for calculation of the bearing capacityof the foundation. The results of the soil investigation at the three-point drill showed the averagedepth of the bedrock -19.33 m and adhesion 3163.88 kg / cm?. Test boring at point BH1 found thebedrock at a depth of 32 m with a maximum SPT value 16. from the data can be determined theappropriate type of foundation is bored pile. The foundation is the upper structure support which canlead to a reduction / settlement if its bearing capacity is not able to withstand the load on it."

"Interfacial phenomena are commonplace in physics, chemistry, biology, and in various disciplines bridging these fields. They occur whenever a continuum is present which can exist in at least two different chemical or physical "states", and there is some mechanism which generates or enforces a spatial separation between these states. The separation boundary is then called an interface. In the examples studied here, the separation boundary, and its internal structure, result from the balance between two opposing tendencies: a diffusive effect which attempts to mix and smooth the properties of the material, and a physical or chemical mechanism which works to drive it to one or the other pure state. This volume is unique in that the treatment of flames, as well as internal layer dynamics "including curvature effects", is more detailed and systematic than in publications. Mathematicians and natural scientists interested in interfacial phenomena, especially flame theory, the mathematics of excitable media, electrophoresis, and phase change problems, will find Dynamics of Internal Layers and Diffusive Interfaces exceptionally useful."

"Hermeneutics is a theory that deals with text interpretation.This theory is commonly used as a method to understand a text althoughhermenutics itself does not explicity formulate the practical steps to understand to text

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"Sebuah perusahaan dinilai memiliki competitive advantage jika memiliki bisnis yang unik (unique core business) dan teknologi pendukung yang fleksibel serta dapat diandalkan. Salah satu cara perancangan arsitektur dan solusi yang fleksibel dan dapat diandalkan adalah dengan memanfaatkan teknologi SOA. Kajian ini berisi mengenai cara analisa dan desain SOA. Adapun metodologi yang digunakan adalah metodologi yang disusun oleh Thomas Erl. Thomas Erl menawarkan suatu metodologi analisa dan desain yang berorientasi service yang dikenal dengan metodologi agile (meet in the middle). Metodologi ini menggabungkan dua pendekatan metodologi analisa dan desain konvensional, yaitu top down (pendekatan analisa dari kebutuhan bisnis) dan bottom up (pendekatan analisa dari aplikasi / sistem yang sudah ada). Tujuan penggunaan metodologi ini adalah mempercepat waktu yang dipergunakan dalam analisa sekaligus mendapatkan analisa yang mendalam. Proses analisa dan desain berorientasi service ini terdiri atas pengumpulan kebutuhan bisnis, pemodelan service, dan desain lapisan service. Kedua proses ini mengawali proses desain dan pengembangan sistem yang sudah dikenal dalam metodologi tradisional (SDLC). Prinsip SOA yang diterapkan selama proses ini adalah autonomy, reusability, discoverability, dan statelessness. Prinsip ini harus dapat diuji dari hasil desain yang diperoleh selama penerapan metodologi agile. Adapun hasil dari kajian ini adalah desain lapisan service dan desain service yang dapat diterapkan di KBI. Beberapa hal yang dapat disimpulkan selama proses ini adalah penerapan desain berorientasi service perlu memperhatikan sistem yang sudah diimplementasikan, metodologi yang digunakan, dan manfaat yang dapat diperoleh dengan implementasi berorientasi service.

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A company will have competitive advantage in its business if it has a unique core business and robust technology that supports the business. One methode to design an adaptive and flexible architecture is using SOA. This paper is about the design of a service oriented architecture using an agile methodology. The methodology used for designing the service oriented architecture is the agile methodology suggested by Thomas Erl, also known as Meet in the Middle methodology. This methodology combines two traditional methodology approaches: Top Down and Bottom Up. One advantage using agile methodology is to get deep level of analysis from business user?s perspective but relatively short time to design the service from technical perspective. Analysis and Design in SOA consist of few steps: user requirements, service modelling, and service layers design. These processes begin before traditional development (SDLC) starts. SOA?s principles used in these processes are autonomy, reusability, discoverability, and statelessness. These principles will be tested to ensure that the design results are correct. Results of the paper are design of service layers and the services involve in each layers, which represent current KBI business process. The design process takes into account the existing systems, the methodology used, and the benefit gained from the service oriented implementation."

"This study aimed to determine the effect of using acrylonitrile butadiene styrene in place of conventional wax material on treatment pattern removal in the investment casting process. There are three controllable process variables that can affect treatment pattern removal, which include temperature increase, holding time and the number of layers of ceramic shell that have been considered for comparison. Comparison among the effects of temperature increase, holding time and numbers of ceramic shell layers on the ceramic shell was analyzed using ANOVA. It was found that temperature increase (Tx), holding time (t) and number of layers of ceramic shell (N) contribute significantly to the length of the crack (l) on the ceramic shell. The crack in the ceramic shell?s surface was analyzed using scanning electron microscope photos. Less layers number cause the increase of crack length. The combination between temperature upraise and longer holding time cause cracking delay. The experimental is conducted by using 3 (three) variants for each of layers number, temperature and holding time. The layers number is ranging between 7-9 layers. Temperature increase from room temperature until 1300oC. The layers number variant is ranging between 180-300 seconds. It was concluded that a longer holding time will result in a more intact ceramic shell, as longer holding times yield short crack lengths."

"Paduan Al-7wt%Si merupakan salah satu jenis paduan aluminium silikon yang memiliki aplikasi besar dalam dunia pengecoran khususnya proses die casting. Dalam aplikasi di dunia industri die casting terdapat problem yang disebut dengan die soldering. Die soldering adalah fenomena menempelnya aluminium cair pada permukaan material cetakan dan ada bagian benda casting yang tersisa ketika dikeluarkan dari cetakan. Reaksi die soldering biasanya terjadi pada pengecoran cetak tekan dengan tekanan tinggi dalam paduan aluminium dan membentuk lapisan intermetalik antara aluminium cair dan cetakan. Fenomena ini menyebabkan rusaknya cetakan serta mengakibatkan kualitas permukaan cetakan yang jelek, sedangkan biaya akan terus meningkat. Penelitian ini dilakukan untuk melihat karakteristik pembentukan ketebalan dan kekerasan dari lapisan intermetlic selama proses pencelupan. Dalam penelitian ini, ditemukan adanya lapisan fasa binary dari lapisan intermetalik FeAl2, Fe2Al5, and FeAl3 yang ditemukan di permukaan baja. Penelitian ini bertujuan untuk mencari morfologi dan karakteristik dari lapisan AlxFeySiz yang meliputi ketebalan dan kekerasan selama proses pencelupan. Material cetakan untuk penelitian ini adalah baja perkakas H13 yang dicelup dengan Al-7wt%Si dengan temperatur holding 700°C, 720°C, dan 740°C serta penambahan mangan dengan 0.1, 0.3, 0.5, dan 0.7 %. Dari hasil penelitian diperoleh bahwa penambahan mangan diatas 0.3% pada temperatur 700°C efektif menurunkan die soldering dari ketebalan lapisan 101 mikron sampai 86 mikron di kadar 0,5%Mn dan 54 mikron pada kadar Mn 0,7%. Fenomena tersebut juga terjadi pada temperatur 740°C. Sedangkan pada temperatur 720°C, penambahan Mn efektif menurunkan fenomena die soldering setelah penambahan 0.5%Mn. Adapun kekerasan lapisan intermetalik sangat bervariasi, hal ini disebabkan karena ukuran kekerasan sangat tergantung terhadap kandungan paduan FexAly yang terdapat dalam lapisan. Semakin banyak kandungan Fe dalam paduan lapisan intermetalik FexAly, maka kekerasannya semakin meningkat, begitu juga sebaliknya. Dengan demikian, penambahan mangan terhadap Al-7wt%Si tidak mempunyai pengaruh yang signifikan terhadap kekerasan lapisan intermetalik.

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Al-7wt%Si is one of aluminium alloys which have largest application in the world of casting, especially in die casting process. In the application of die casting technology, there is a dominant problem names die soldering. Die soldering is a phenomenon in which molten aluminium ?welds? to the die surface and remains there after the ejection of the part. Soldering reactions are commonly observed during high pressure die casting of aluminium alloys, and involve the formation and growth of interfacial intermetallic layers between the die and the cast alloy. This phenomenon resulting in damage to the die and poor surface quality of the casting, but increase the production cost. This research is done to study the thickness and hardness characteristic formation of the intermetallic layers during dipping test.

In this research, the appeared binary phase of intermetallic layer is FeAl2, Fe2Al5, and FeAl3 which available at steel?s surface. This research aim is investigating morphology and characteristic of AlxFeySiz intermetallic layer which consist thickness and hardness of the layer during immersing period. The testing material for this research is annealed tool steel H13 which is immersed at Al-7%Si with various holding temperature at 700°C, 720°C, and 740°C and also added by four types mangan (Mn) composition at each temperature. The compositions of this mangan are 0.1, 0.3, 0.5, and 0.7 %.

From the laboratory activity, it was clearly shown that additional Mn above 0.3% at 700°C can decrease die soldering effect significantly. This phenomenon can be seen from the intermetallic layer thickness formed with additional Mn at 101 to 86 micron for 0.5% Mn content and 54 micron for 0.7% Mn. This tendency is happen for 740°C reacting temperature also. But for 720°C reacting temperature, the effect of additional Mn for decreasing die soldering effect start from 0.5% Mn content.

Then, intermetallic layer formed are vary due to FexAly alloy content at layer itself. The more FexAly alloy content, the more hardness level formed; and vice versa. So that, additional Mn to Al-7wt%Si did not have significant effect to hardness of intermetallic layer formed due to spreading of random hardness level at each intermetallic layer."