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"Ring kabin adalah sebentuk material yang cukup penting berkaitan dengan pemasangan haut dan mur pada bagian mesin. Ring ini diproduksi secara massal dengan dua pasangan punch dan die (matres sederhana). Dalam memproduksi ring kabin, sering dijumpai beberapa kekurangan yang bersifat teknis karena kurang memperhitungkan sifat-sifat mekanis bahan serta jenis dan dimensi dari alat pembentukannya, juga beberapa kelemahan antara lain belum maksimalnya pengaturan strip lay out material sehingga terjadi pemborosan material, dan laju produksi yang kurang tinggi, karena dalam dua proses hanya satu benda kerja yang dihasilkan. Dalam perencanana ini akan direncanakan matres dengan type progressive dies yang terdiri dari dua stasiun kerja, yaitu stasiun kerja satu untuk proses piercing dan stasiun kerja dua untuk proses blanking. Sehingga dalam satu kali proses dapat langsung dihasilkan satu benda kerja berupa ring kabin. Langkah- langkah yang dilakukan yaitu menentukan strip lay out material, mengetahui sifat-sifat mekanis banda kerja dan material perkakas yang digunakan, selanjutnya disain progressive dies."

"Optical Ring Resonators (ORR), whether based on fiber optics or an optical micro ring on substrate structures have been studied and explored extensively to be used for optical sensor applications. The outstanding advantage of optical ring resonator structure is its spectral response shape change due to the variations of the refractive index of the surrounding medium, medium loss due to absorption and scattering, and coupling loss between waveguides in the optical ring structure. The change of spectral response due to the variations of optical medium on the optical ring structure is a phenomenon that can be used to sense the optical property change of physical or biological materials. Some developments of Waveguide (WG) ORR sensors are in progress mostly for bio-sensor applications, since it is free from Electromagnetic Interference (EMI) and is non-physically destructive. In this paper, we discuss our research in developing optical bio-sensor in the form of a WG optical ring resonator. The focus of the research is optimizing the coupling region as sensing area to obtain the optimal coupling coefficient for the most sensitive sense. The results show that the variations of coupling coefficient is not linear with respect to the resonant peak output, such that we are able to locate the most sensitive coupling coefficient to sense."

"Each Organization public sector or private have a goals. Strategy need reach a goal oforganization. It is describe at activities. Organization need reins management system forguarantee to do of strategy organization effective and efficient system. The system for guarantee to do of strategy organization is decision maker at government region. The example is Outer ring road Semarang. Semarang have strategy position for national road, Outer ring road Semarang. Semarang have strategy position for national road, Outer ring road Semarang.Semarang has a strategy position for national road, province road, regency road and city road.In order to do need strategy management coordination each regent. Central Government haveplan build ring road Semarang-Solo need supported Government Semarang. The Conclusionis, first alternative Trase (Gunung Pati street, Cangkiran, Kalimas, Mangkang) have highfeasibility views. First alternative have some problem. Problem solving need a good branchof road, consistency middle ring road plan at BSB (Bukit Semarang Baru Regency). Second alternative (Pramuka Street, New street, Kalimas and Mangkang) have feasibility stage two.Second alternative needs progress anticipate for conservation region plan, middle ring roadplan, space regulation specific for growth ple, intensive socialization society"

"Minyak kelapa sawit berpotensi sebagai bahan baku pembuatan pelumas bio, selain renewable dan biodegradable, juga bersifat non-toxic, sehingga dapat digunakan sebagai pelumas bahan makan atau pelumas food-grade. Telah dilakukan pembuatan pelumas bio berbasisi minyak kelapa sawit melalui 3 tahap yaitu trans-esterifikasi, epoksidasi dan reaksi pembukaan cincin dengan gliserol. Terdapat kendala pada reaksi pembukaan cincin, yaitu dalam pemilihan katalis. Katalis PTSA (p-Toluenesulfonic acid) mempunyai keasaman tinggi, tetapi sulit dipisahkan karena katalis homogen. Digunakan H-zeolit dan alumina yang merupakan katalis heterogen, tetapi yield yang didapat cukup rendah, karena memiliki luas permukaan yang kecil. Pada penelitian ini dilakukan reaksi pembukaan cincin dengan gliserol menggunakan amberlyst-15 yang merupakan katalis heterogen, memiliki keasaman yang tinggi dan luas permukaan yang cukup besar untuk memperbaiki kelemahan-kelemahan katalis-katalis sebelumnya. Reaksi yang dilakukan adalah 2% dan 2,5% berat penambahan amberlyst-15 pada T=1000C dengan variasi waktu 12, 16, 20, dan 24 jam. Keberhasilan reaksi dilihat dari uji densitas, viskositas, FTIR, dan gliserol yang tersisa. Hasil penelitian menunjukkan bahwa amberlyst-15 mampu membuka cincin lebih baik dibandingkan PTSA, H-zeolit dan alumina (dilihat dari besarnya densitas dan viskositas), dan mampu menghasilkan yield sebesar 94,88% (dilihat dari sisa gliserol yang tidak bereaksi). Dari uji yang dilakukan, spektrum FTIR memperlihatkan bahwa gugus gliserol teradisi ke dalam produk. Penambahan amberlyst-15 sebanyak 2% lebih efektif dibandingkan 2,5%.

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Palm oil has high potential as raw material for biolubricant product, beside of its tendency to be renewable, biodegradable, and non-toxic as well so it can be used as a lubricant for food ingredients or food-grade lubricants. Up until now, the making of lubricating oil based Palm oil can be done through three phases, such as trans-esterification, epoxidation and ring opening reaction with glycerol. However, there are constraints on the ring opening reaction, mostly in the selection of the catalyst. PTSA catalyst (p-Toluenesulfonic acid) has high acidity, but it is difficult to separate because of it charasteristic as homogeneous catalyst. H-zeolite and alumina are heterogeneous catalyst, but the yield obtained is low enough, because it has smaller surface area.

This research use ring opening reaction with glycerol phase by using amberlyst-15 as catalyst. Amberlyst-15 is a heterogeneous catalyst, has high acidity and surface area that large enough to fix the weaknesses of other catalysts. The reaction was performed with 2%w and 2.5%w amberlyst -15 additions at T = 1000ºC with varying time 12, 16, 20, and 24 hours. The success of the reaction can be seen from the density and viscosity test, FTIR, and the remaining glycerol.

The results showed that amberlyst-15 capable to open the ring better than the PTSA, H-zeolite and alumina (as seen from the high density and viscosity number), and capable to produce yield of 94.88% (as seen from the remaining glycerol wich didn?t react). FTIR spectra showed that the product has adsorb glycerol clusters. The result also showed that Amberlyst-15 additions as much as 2% is more effective than 2.5%."