2-DELTA-FUNCTION GENERALIZED PLASMA POLE MODEL FOR 1ST PRINCIPLE CALCULATIONS OF QUASI-PARTICLE ENERGIES IN MANY-ELECTRON SYSTEMS

To evaluate the dynamical effects of the screened interaction in the calculations of quasiparticle energies in many-electron systems a two-delta-function generalized plasma pole model (GPP) is introduced to simulate the dynamical dielectric function. The usual single delta-function GPP model has the drawback of over simplifications and for the crystals without the center of symmetry is inappropriate to describe the finite frequency behavior for dielectric function matrices. The discrete frequency summation method requires too much computation to achieve converged results since ab initio calculations of dielectric function matrices are to be carried out for many different frequencies. The two-delta GPP model is an optimization of the two approaches. We analyze the two-delta GPP model and propose a method to determine from the first principle calculations the amplitudes and effective frequencies of these delta-functions. Analytical solutions are found for the second order equations for the parameter matrices entering the model. This enables realistic applications of the method to the first principle quasiparticle calculations and makes the calculations truly adjustable parameter free.

1st Kassel Student Workshop on Security in Distributed Systems

With this document, we provide a compilation of in-depth discussions on some of the most current security issues in distributed systems. The six contributions have been collected and presented at the 1st Kassel Student Workshop on Security in Distributed Systems (KaSWoSDS’08). We are pleased to present a collection of papers not only shedding light on the theoretical aspects of their topics, but also being accompanied with elaborate practical examples. In Chapter 1, Stephan Opfer discusses Viruses, one of the oldest threats to system security. For years there has been an arms race between virus producers and anti-virus software providers, with no end in sight. Stefan Triller demonstrates how malicious code can be injected in a target process using a buffer overflow in Chapter 2. Websites usually store their data and user information in data bases. Like buffer overflows, the possibilities of performing SQL injection attacks targeting such data bases are left open by unwary programmers. Stephan Scheuermann gives us a deeper insight into the mechanisms behind such attacks in Chapter 3. Cross-site scripting (XSS) is a method to insert malicious code into websites viewed by other users. Michael Blumenstein explains this issue in Chapter 4. Code can be injected in other websites via XSS attacks in order to spy out data of internet users, spoofing subsumes all methods that directly involve taking on a false identity. In Chapter 5, Till Amma shows us different ways how this can be done and how it is prevented. Last but not least, cryptographic methods are used to encode confidential data in a way that even if it got in the wrong hands, the culprits cannot decode it. Over the centuries, many different ciphers have been developed, applied, and finally broken. Ilhan Glogic sketches this history in Chapter 6.

1st and 2nd Generation Ethanol from Biomass Crops

In chapter 1 and 2 calcium hydroxide as impregnation agent before steam explosion of sugarcane bagasse and switchgrass, respectively, was compared with auto-hydrolysis, assessing the effects on enzymatic hydrolysis and simultaneous saccharification and fermentation (SSF) at high solid concentration of pretreated solid fraction. In addition, anaerobic digestion of pretreated liquid fraction was carried out, in order to appraise the effectiveness of calcium hydroxide before steam explosion in a more comprehensive way. In As water is an expensive input in both cultivation of biomass crops and subsequent pretreatment, Chapter 3 addressed the effects of variable soil moisture on biomass growth and composition of biomass sorghum. Moreover, the effect of water stress was related to the characteristics of stem juice for 1st generation ethanol and structural carbohydrates for 2nd generation ethanol. In the frame of chapter 1, calcium hydroxide was proven to be a suitable catalyst for sugarcane bagasse before steam explosion, in order to enhance fibre deconstruction. In chapter 2, effect of calcium hydroxide on switchgrass showed a great potential when ethanol was focused, whereas acid addition produced higher methane yield. Regarding chapter 3, during crop cycle the amount of cellulose, hemicellulose and AIL changed causing a decrease of 2G ethanol amount. Biomass physical and chemical properties involved a lower glucose yield and concentration at the end of enzymatic hydrolysis and, consequently, a lower 2G ethanol concentration at the end of simultaneous saccharification and fermentation, proving that there is strong relationship between structure, chemical composition, and fermentable sugar yield. The significantly higher concentration of ethanol at the early crop stage could be an important incentive to consider biomass sorghum as second crop in the season, to be introduced into some agricultural systems, potentially benefiting farmers and, above all, avoiding the exacerbation of the debate about fuel vs food crops.

Directions for impregnating water with fixed air in order to communicate to it the peculiar spirit and virtues of Pyrmont water,

"Priestley and carbonated waters, by John J. Riley": p. [1]-17 (1st group)

History of the expedition under the command of Captains Lewis and Clarke, to the sources of the Missouri ... : performed during the years 1804, 1805, 1806, by order of the government of the United States /

The chapter on natural history (1st edition, v. 2, chapter 7) is in this edition transferred to the appendix. In this appendix the Estimate of the western Indians is given under the heading: "Enumeration of Indian nations and their places of general residence."

The victory of the Marne; the enemy's onslaught--order to stand firm--the battle--immediate results--historic consequences, /

Mode of access: Internet.

Miscellaneous documents printed by order of the House of Representatives, during the first session of the thirtieth Congress, begun and held at the city of Washington, December 2, 1847 ...

"In one volume. Containing documents from no. 1 to no. 100."

Gazetteer to maps of Hokkaidō and Karafuto. Map series AMS L764, L761 and L762 (1st ed.) Scale 1:50,000. January 1945.

"Conversion tables of Romaji equivalents (Goju-on Order)" [katakana]: p. x-xv.

History of the expedition under the command of Captains Lewis and Clarke, to the sources of the Missouri : thence across the Rockey Mountains, and down the river Columbia to the Pacific Ocean ; performed during the years 1804, 1805, 1806, by order of the government of the United States /

The chapter on natural history (1st edition, v. 2, chapter 7) is in this edition transferred to the appendix. In this appendix the Estimate of the western Indians is given under the heading: "Enumeration of Indian nations and their places of general residence".

The constitution and by-laws of the Independent Company of Cadets : with extracts from the laws of the U. States and the militia laws of Massachusetts : to which is prefixed an order of Lt. Colonel David Sears, with authority for the formation of a full battalion : accompanied by papers and documents relative to the Divisionary Corps of Independent Cadets.

Mode of access: Internet.

Memorial of the New-York Chamber of Commerce, to the Hon. the Senate and House of Representatives of the United States, in Congress assembled; with statements, prepared by order of the Chamber, to show the present rate of duties, and the rate of duties proposed by the tariff bill, now before Congress. With remarks, &c.

The memorial is signed on p.12: By order of the Chamber of Commerce, William Bayard, President. ... New-York, January 30, 1824.

Precedents. Decisions on points of order with phraseology in the United States Senate from the First Congress to end of the Sixtieth Congress, 1789-1909.

Issued also as Senate Document no. 129, 61st Cong., 1st sess.

Ultrafast all-optical Nth-order differentiator based on chirped fiber Bragg gratings

In this letter we present a technique for the implementation of Nth-order ultrafast temporal differentiators. This technique is based on two oppositely chirped fiber Bragg gratings in which the grating profile maps the spectral response of the Nth-order differentiator. Examples of 1st, 2nd, and 4th order differentiators are designed and numerically simulated.