Finite dimesional Hamiltonian formalism for gauge and field theories

We discuss in this paper the canonical structure of classical field theory in finite dimensions within the {\it{pataplectic}} Hamiltonian formulation, where we put forward the role of Legendre correspondance. We define the generalized Poisson $\mathfrak{p}$-brackets which are the analogues of the Poisson bracket on forms. We formulate the equations of motion of forms in terms of $\mathfrak{p}$-brackets. As illustration of our formalism we present three examples: the interacting scalar fields, conformal string theory and the electromagnetic field.Comment: 52 pages. In this paper we give a more general hamiltonian formulation for a gauge and field theories, it's an extension of our previous paper math-ph/000402

A program to evaluate a control system based on feedback of aerodynamic pressure differentials, part 1

The use of pressure differentials in a flight control system was evaluated. The pressure profile around the test surface was determined using two techniques: (1) windtunnel data (actual); and (2) NASA/Langley Single Element Airfoil Computer Program (theoretical). The system designed to evaluate the concept of using pressure differentials is composed of a sensor drive and power amplifiers, actuator, position potentiometer, and a control surface. The characteristics (both desired and actual) of the system and each individual component were analyzed. The desired characteristics of the system as a whole are given. The flight control system developed, the testing procedures and data reduction methods used, and theoretical frequency response analysis are described

Should we use CT or MRI for detection and characterization of benign adrenal lesions?

OBJECTIVES: Computed tomography (CT) and magnetic resonance imaging (MRI) are the main imaging modalities used for analysis of adrenal lesions. We compared the ability of CT and MRI to detect and characterize benign adrenal lesions. ----- PATIENTS AND METHODS: Unenhanced abdominal CT and MRI were performed in 16 patients (age range 39-77), and reviewed by a radiologist with 6years of experience in abdominal imaging. The presence, number, size and structure of each mass were analyzed and compared between the two modalities. ----- RESULTS: There were 18 adrenal masses in 11 patients, four patients had adrenal hyperplasia (AH), whereas one patient had left-sided AH and right-sided adenoma. Ten masses were≥2cm in diameter, and were perfectly depicted using CT and all MRI techniques. There were nine masses with diameter10Hounsfield units could not be characterized using unenhanced CT, but three of them were characterized using MRI. ----- CONCLUSION: CT has higher sensitivity for detection of small adrenal tumours and adrenal hyperplasia than MRI. MRI is an important tool in characterization of adrenal masses that could not be characterized using unenhanced CT

Catalonians’ Participation in Traffic, Grains, Salt, Metals, Corals and Loans (till 1520)

Značaj jednog privrednog središta u srednjem veku ne ceni se samo po tome koliko su žitelji takvog grada sudelovali u trgovinskom životu svoje regije i šire nego i po tome koliko su ljudi sa strane imali potrebe i volje da tu posluju, donose svoju robu i kapitale i ostvaruju unosnu dobit, odnosno da preko konkretne varoši i njezinih saobraćajnih kanala i komercijalnih veza uspostavljaju dodire sa trećima. Dubrovnik, naročito od vremena svoje zrele ekonomike (1420), svojim položajem, posredničkom ulogom prema balkanskom kopnu, Levantu i Ponentu, a napose svojom poznatom trgovačkom mornaricom i pratećim ustanovama (pomorskim osiguranjem, zdravstvenom službom, kreditnom i meničnom službom) zais­ta je mogao da pruži priliku za uspešan rad i dobru zaradu i trgovcima putnicima i verziranim strancima koji bi u njemu svili i svoje porodično gnezdo.The period of the Catalonians\u27 economic expansion on to the Dubrovnik business area can be determined by the years of 1418 and 1513. They appeared in Dubrovnik as importers of wool and food and as exporters of ores and corals (from the Dubrovnik archipelago). For almost half a century (1418—1468) they were the most important factor in crediting to the Dubrovnik economy. Their loans were not of a rentier\u27s or usurer\u27s character. They were all in the function of wool trade. The Catalonians were always standard merchants selling their goods for ready money, rarely entering trade by exchange and never into more complicated transactions. Being occupied more with selling wool, less with the import of Apulian, Sicilian and West Balkan wheat, and least with the import of salt and other food, they inadequately combined imports with exports from Dubrovnik. They did not care for both more complicated trade operations and money transactions (such as silver). They did not reach the level that at the same time meant banking, renting and shipping business, which were already known to Florentines and Venetians. With such a simplified profit they were less dangerous to the development of the Dubrovnik cloth manufacture and trade than the Italians. On the other side Dubrovnik Government stimulated the Catalonians\u27 efforts to make use of Dubrovnik ships in their transports towards Alexandria. The Catalonians were driven out from the Dubrovnik business area less by the Florentines, who had already taken over many of their business agenda, but more by the supreme state authorities. When the import of silver and lead from Bosnia and Serbia was strictly forbidden, and when Dubrovnik started taking care of her food supplies, the Catalonians did not have any reason to continue their business activities in this area