Power Efficient Fpga Implementation Of Rsa Algortihm

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2010Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2010Bu çalışmada Rivest, Shamir, Adleman (RSA) algoritması sahada programlanabilir kapı dizisi üzerinde gerçeklenmekte ve güç tasarruf yöntemlerinden yararlanılarak dinamik güç harcamaları azaltılmaktadır. RSA algoritması en yaygın kullanıma sahip açık anahtarlı şifreleme algoritmalarından biridir. RSA algoritmasını oluşturan matematiksel temel işlemleri iki ana başlıkta toplamak mümkündür: moduler çarpma işlemi ve moduler üs alma, exponent işlemi. RSA algoritmasında kullanılan aritmetik işlem ME mod N işlemidir. Bu işlemdeki N sayısı aralarında asal iki sayının çarpımından oluşan modulo değeri, M mesaj ya da düz metin dediğimiz bilgi, E ise açık anahtar olarak bilinen değerdir. İyi bir RSA gerçeklemesi oluşturmak istenirse; yapılması gereken en önemli şey, iyi bir modular çarpma devresi oluşturmaktır. Bu matematiksel açıklamalardan yola çıkararak anlamalıyız ki; bir RSA gerçeklemesinde en çok güç tüketen blok modular çarpma devresidir. Bu nedenle güç tüketimlerinin karşılaştırılması açısından modular çarpma devresine farklı teknikler uygulanmıştır. Daha sonra çok yaygın bir kullanıma sahip olan ardışıl ikili modular üs alma tekniği ile RSA algoritması gerçeklenmiştir. Bilgisayar benzetim programı ile yapıların test vektörü girişlerine karşılık doğru sonuçlar verdiği gösterilmiştir.In this study, dynamic power consumptions of Field Programmable Gate Array (FPGA) implementations of the Rivest, Shamir, Adleman (RSA) has been reduced by using low power design methods. RSA is one of the most popular public key cryptographic algorithms. The mathematics behind RSA algorithm, are summarized in two operations, modular multiplication and modular exponentiation. In the RSA cryptosystem, the arithmetic operation ME mod N is used, where N is a prime product of two relative prime numbers, M is the message and E is the public key. In order to create an efficient implementation of RSA, one has to design efficiently the multiplication of two modular numbers. So this mathematical background provides a good understanding that Modular Multiplication block dissipates the most of the power, dissipated in RSA. For comparison of power dissipations, different methods are used to implement Modular Multiplication block. Then RSA implemented by using Sequential Binary Modular Exponentiation which has widespread applications. Computer simulations have been used to show that the implementations of the algorithm generate correct outputs against test vectors.Yüksek LisansM.Sc

Feasibility and potential of separate anaerobic digestion of municipal sewage sludge fractions

Feasibility of the separate anaerobic stabilization of primary (PS) and secondary (SS) sludge fractions produced in municipal wastewater treatment plants (WWTP) was studied at volatile loading rates (VLR) of 0.57–2.05 and 0.27–0.57 kg VS/(m3∙d) for PS and SS, respectively, corresponding to 16–30 and 14–28 d of hydraulic retention time (HRT). Laboratory-scale semi-continuous anaerobic reactors were operated at 35°C. The operational performance and quality of the final stabilized sludge were monitored. PS and SS showed opposite thickening abilities exhibiting a need for direct feeding of PS to the digesters. Biodegradability was obtained as 52(±1) and 40(±5)% volatile solid (VS) removal for PS and SS, respectively. Optimum VLR was determined according to the highest methane yield (specific methane production), VS reduction and dewaterability of the stabilised sludge. An inhibitory effect was observed at higher VLRs in PS digestion inducing a gradual reduction in the methane yield and daily production. High oil and grease content was subject to a substantial reduction in PS digestion showing a dependency on HRT. Conversely, a considerable degree of augmentation took place in the stabilised SS with no correlation to HRT at values lower than 30 d. Efficient reduction in the oil and grease content improved dewaterability in stabilised PS whereas high oil and grease content prevented an improvement for stabilised SS. Major benefits were obtained as lower HRT and high stability with higher methane production and fertilizing (N and P content) characteristics for digestion performance and stabilized SS, whereas direct feeding and higher HRT for PS digestion were determined as beneficial.Keywords: sewage sludge, anaerobic, stabilization, primary, secondary, operation, methane, dewaterabilit

Feasibility and potential of separate anaerobic digestion of municipal sewage sludge fractions

Feasibility of the separate anaerobic stabilization of primary (PS) and secondary (SS) sludge fractions produced in municipal wastewater treatment plants (WWTP) was studied at volatile loading rates (VLR) of 0.57–2.05 and 0.27–0.57 kg VS/(m3∙d) for PS and SS, respectively, corresponding to 16–30 and 14–28 d of hydraulic retention time (HRT). Laboratory-scale semi-continuous anaerobic reactors were operated at 35°C.  The operational performance and quality of the final stabilized sludge were monitored. PS and SS showed opposite thickening abilities exhibiting a need for direct feeding of PS to the digesters. Biodegradability was obtained as 52(±1) and 40(±5)% volatile solid (VS) removal for PS and SS, respectively. Optimum VLR was determined according to the highest methane yield (specific methane production), VS reduction and dewaterability of the stabilised sludge. An inhibitory effect was observed at higher VLRs in PS digestion inducing a gradual reduction in the methane yield and daily production. High oil and grease content was subject to a substantial reduction in PS digestion showing a dependency on HRT. Conversely, a considerable degree of augmentation took place in the stabilised SS with no correlation to HRT at values lower than 30 d. Efficient reduction in the oil and grease content improved dewaterability in stabilised PS whereas high oil and grease content prevented an improvement for stabilised SS. Major benefits were obtained as lower HRT and high stability with higher methane production and fertilizing (N and P content) characteristics for digestion performance and stabilized SS, whereas direct feeding and higher HRT for PS digestion were determined as beneficial. &nbsp

Some parameters of the population biology of spoted flounder (Citharus linguatula Linnaeus, 1758) in Edremit Bay (North Aegean Sea)

A total of 1096 spotted flounder (Citharus linguatula Linnaeus, 1758) were caught in Edremit Bay from September 1998 to September 2000. Length-weight relationships, age, growth, mortality and sex ratio of the samples were investigated. Within the population of this species, most of the individuals in our samples ranged from 100 to 160 mm (69.63%), the minimum and maximum total lengths of the specimens being 69 and 222 mm, respectively. Positive allometric growth was observed for male, female and all fish. Age distribution of the samples was from 1 to IV. There was no significant difference between observed and calculated (von Bertalanffy and back calculation) average total lengths of the age groups (P ;gt; 0.05). The sex ratio (femalesrmales) was 1:1.27. The total (Z), natural (M) and fishing mortality (F) rates, and the exploitation ratio (E) for all individuals were estimated respectively as Z = 0.60, M = 0.75, F = 0.15 and E = 0.25. This shows that the spotted flounder stock of Edremit Bay is being exploited at a lower than optimal level.Edremit Körfezi'nden Eylül 1998-2000 yılları arasında toplam 1096 adet pisi balığı (Citharus linguatula Linnaeus, 1758) yakalandı. Örneklerin boy-ağırlık ilişkileri, yaş, büyüme, mortalite ve eşey oranı araştırıldı. Bu türün populasyonundan elde edilen bireylerin çoğu 100-160 mm (% 69,63) arasında dağılım gösterip türlerin en az ve en yüksek total boylan sırasıyla 69 ve 222 mm' dir. Erkek, dişi ve tüm bireyler için pozitif allometri gözlenmiştir. Bireylerin yaş dağılımı 1-IV arasında bulunmuştur. Tüm yaş gruplarında gözlenen ve hesaplanan (von Bertalnffy ve geri hesaplama) ortalama total boylar arasında önem farkı yoktur (P > 0,05). Eşey oranı (dişherkek) 1:1,27 dir. Toplam (Z), doğal (M) ve balıkçılıktan gelen mortalite (F) oranları, sömürü oranı (E) tüm bireyler için sırasıyla Z = 0,60, M = 0,75, F = 0,15 ve E = 0,25 olarak hesaplanmıştır. Bu Edremit Körfezi'ndeki pisi balığı stoğunun optimal sömürüden daha düşük düzeyde sömürüldüğünü göstermektedir

Edremit Körfezi'ndeki yassı balık türleri ve bu türlerden Citharus linguatula (Linnaeus,1758), Arnoglossus laterna (Walbaum,1792) Arnoglossus kessleri (Schmidt,1915)'nin boy-ağırlık ilişkileri

In this study, the biological charecteristics of fish species belong to Heterosomata order was investigated in Edremit Bay. A total of 10 flatfish species were captured by deep-trawl between 1998-2000. The lenght-weight relationships, and length-weight frequency distribution were given for three of them (Citharus linguatula, Arnoglossus laterna and Arnoglossus kessleri).Bu araştırma Edremit Körfezi'nde Heterosomata (Pleuronectiformes) ordosuna ait balık türlerini ve bunların bazı biyolojik özelliklerini belirlemek amacıyla yapılmıştır. 1998-2000 yılları arasında Edremit Körfezin'de yapılan trol çekimlerinden 10 yassı balık türü ele geçirilmiştir. Bunlardan 3 türün (Citharus linguatula, Arnoglossus laterna ve Arnoglossus kessleri), boy-ağırlık ilişkileri ve boy-ağırlık frekansları verilmiştir