947 research outputs found
A proposito di "Il perdono responsabile. Le alternative alla punizione e alle pene tradizionali" (di Gherardo Colombo), Ponte alle Grazie, 2011)
No full textPresentazione e recensione del volume di Gherardo Colombo di cui al titolo. L'occasione fornisce inoltre il giusto stimolo per riflettere sul significato costituzionale della pena e sull'opportunità di adottare soluzioni alternative alla mera detenzione. Ciò anche alla luce di una serie di paradossi che riguardano gli effetti stessi delle pene tradizionali: a esempi di tal genere messi in luce nel volume recensito se ne aggiungono così di ulteriori
PERFORMANCE ASSESSMENT OF A MICROTURBINE-BASED COGENERATIVE PLANT
No full textThis paper presents the results of an experimental analysis performed on a microturbine-based small cogenerative plant. The aim of the experimental campaign was to verify behavior and performances of the microturbine at both full and partial load. Attention was particularly paid to the energy saving indexes defined in the AEEG 42/02 Directive (Italian Authority for electrical energy and gas) and EU Directive 2004/8/EC, which is more strict. Such indexes are the energy saving index IRE, the thermal limit LT (AEEG 42/02) and the primary energy saving PES (EU 2004/8/EC). The results of the experimental campaign show that a cogenerative plant equipped with a microturbine as a prime mover can easily exceed the minimum values of the energy saving index imposed by the current directives during operation at full load. On the contrary, very accurate design of the plant and prediction of the load profiles are required to get acceptable results if operation at partial load becomes necessary
A detailed characterization of viscous oil-water flows downward sudden contractions in horizontal pipes
No full textTwo-phase flows of viscous oil and water through singularities such as sudden area contractions/expansions have been taken into limited consideration in the relevant scientific literature. Nevertheless, they play a role of primary importance in industrial systems, for instance, but not only, in the exploitation of oil wells and pipelines. The proposed work is based on the comparison of photographic images of the flow patterns taken from three points of view, i.e. upper, lower and frontal, thanks to a couple of mirrors ???45° inclined with respect to the horizontal plane. Oil-water flow regimes have been observed both upward and downward of five horizontal test sections with area contractions d/D = 40/50, 30/50, 30/40, respectively. The observed structures of the oil-water interface, especially for core-annular flows, has suggested also detecting flow patterns in a 30 mm straight pipe for sake of comparison. Actually, the shape of the oil-core interface appears significantly influenced by the sharp-edged area change as well as by the expected momentum variation
SEMI-EMPIRICAL ANALYSIS OF THE CRITICAL TRANSITION FROM ANNULAR TO WAVY-STRATIFIED OIL-WATER ADIABATIC FLOW WITHIN HORIZONTAL AND SLIGHTLY INCLINED PIPES
No full textThe main subject of this paper concerns the critical transition from annular to wavy-stratified oil-water adiabatic flow within horizontal and slightly inclined pipes. The transition is referred to as critical because it occurs suddenly, giving rise to a sharp and strong increase in the pressure drop due to the contact of the high-viscosity oil with the pipe wall. This could be a dangerous accident, e.g. in pipelines operation, because the peak-wise increase in the pressure drop might give rise to a “chugging” phenomenon in the flow.
Experimental runs were performed on eight test sections of both Plexiglas® and Pyrex® pipes with internal diameters ranging from 21.5 mm to 50 mm, using tap water and viscous oil (ρo=890 kg/m^3, μo=0.9 Pa s at 20°C). Inclination angles from 0 to 6 deg upward were tested. Water and oil superficial velocities were varied in their proper range and the pressure drop was measured for several combinations of these quantities. Flow pattern visualizations were also taken by a CCD photo-video camera in order to draw flow pattern maps.
Based on these findings, the transition boundary between annular and wavy-stratified flow was analytically determined and compared with the data reported in the existing flow pattern maps
Characterization of the critical transition from annular to wavy-stratified flow for oil-water mixtures in horizontal pipes
No full textThe transition from annular to wavy-stratified oil-water adiabatic flow within horizontal pipes is experimentally analysed and a semi-empirical model is proposed. The transition is referred to as critical because it occurs suddenly, giving rise to a sharp and strong increase in the pressure drop due to the contact of the high-viscosity oil with the pipe wall. This could lead to a dangerous accident in pipelines. Experimental runs were performed on eight test sections of both Plexiglas® and Pyrex® pipes with internal diameters ranging from 21.5 mm to 50 mm, using tap water and oil with viscosity about 880 times higher than that of water. On the basis of pressure drop measurement and flow pattern visualization, the transition boundary between annular and wavy-stratified flow was analytically determined and compared with flow pattern maps
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On rules /
No full textJustice is simultaneously a practical and an ideal concept: when we think of justice, we refer to its day-to-day administration, involving police, lawyers, judges, and politicians-but we also refer to a larger ideal, a set of basic values that guide our attempts to live together and balance competing interests, obligations, and freedoms. If we lose sight of the practical, the ideal will fail-but if we forget the ideal, the practical becomes pointless. On Rules is the culmination of decades of thinking about and working within the law as both ideal and realm of practical action. Gherardo Colombo brings to his rich philosophical analysis of the culture of justice thirty years of experience in the Italian judiciary, which saw him head up numerous important and sensitive commissions and inquiries. His exploration of the concept and application of rules of justice is powerful and clear: if we don't root our experience in a fundamental respect for rules, we cannot have a functioning, just society
Orbit design for future SpaceChip swarm missions in a planetary atmosphere
No full textThe effect of solar radiation pressure and atmospheric drag on the orbital dynamics of satellites-on-a-chip (SpaceChips) is exploited to design equatorial long-lived orbits about the oblate Earth. The orbit energy gain due to asymmetric solar radiation pressure, considering the Earth's shadow, is used to balance the energy loss due to atmospheric drag. Future missions for a swarm of SpaceChips are proposed, where a number of small devices are released from a conventional spacecraft to perform spatially distributed measurements of the conditions in the ionosphere and exosphere. It is shown that the orbit lifetime can be extended and indeed selected through solar radiation pressure and the end-of-life re-entry of the swarm can be ensured, by exploiting atmospheric drag
Development of the hub port of Colombo, Sri Lanka
No full textThe Port of Colombo, Sri Lanka, is an important hub port in the Indian Ocean. A hub port is a port with mainly transhipment (and in this case container) throughput, which means that most of the cargo is not for the country itself, but for countries in the region. The yearly container throughput at the Port of Colombo reached its full capacity of 1.7 million TEU per year in 1997. Increasing waiting times for ships calling at the port are a result of this. Because of the costs of a waiting ship, shipping lines will choose other ports in the region such as Singapore, Salalah (Oman) or Dubai (United Arab Emirates) for their ships to go to. The aim of this study is to develop a plan for a New Container Terminal, which will give the Port of Colombo enough container throughput capacity for the next 25 years: till the year 2025.Hydraulic EngineeringCivil Engineering and Geoscience
Dissomphalus miriamae Colombo & Azevedo, sp. nov.
No full textDissomphalus miriamae Colombo & Azevedo, sp. nov. (Figs 12, 150, 151) Description. Male. Head and mesosoma black; metasoma dark castaneous or black. Mandible with two apical teeth; clypeus broadly projected forward, median tooth weakly rounded; frons weakly coriaceous and punctate. Mesosoma. Weakly coriaceous. T2 without tergal process. Posterior hypopygeal margin concave. Genitalia: paramere small in dorsal view, apex rounded, arched, smaller than basiparamere; cuspis wide; digitus wide; aedeagal ventral ramus smaller than dorsal body, apex ill defined, laminar, narrow; aedeagal dorsal body with one pair of apical lobes, inner pair with apex rounded in dorsal view, inner pair weakly serrate; basal process ill defined; apodeme extending beyond genital ring. Female unknown. Remarks. This species is allocated in amplus species-group by having the tergal process absent. This species not is similar other of species-group. This species is mainly different because has the aedeagal dorsal body with one pair of apical lobes and inner pair weakly serrate. Material examined. Types: Holotype Ƌ, BRAZIL, E[spírito] S[anto]: Santa Teresa, Est [ação] Biol [ógica] de Santa Lúcia, 28.III.2001, varredura, Azevedo & Kawada col. (UFES). Paratypes: 2Ƌ, Santa Teresa, Est [ação] Biol [ógica] de Santa Lúcia, 31.V.2001, 2♂, 27.IX.2001, varredura, Azevedo & Kawada col. (UFES); 1♂, Santa Maria de Jetibá, Fazenda Paulo Seick, 20º02’S 40º42’W, 29.XI–06.XII.2002, armadilha Malaise, Tavares & Azevedo e eq[uipe] col. (UFES); 1♂, Vitória, P [ar]q[ue] Est [adual] Fonte Grande, 30.VI.2001, varredura, Azevedo & Kawada col. (UFES). Etymology. The epithet miriamae is in allusion to the mother’s second author name Miriam. Distribution. Brazil (Espírito Santo).Published as part of Colombo, Wesley D. & Azevedo, Celso O., 2016, Review of Dissomphalus Ashmead, 1893 (Hymenoptera, Bethylidae) from Espíri- to Santo, Brazil, with description of twenty-one new species, pp. 1-84 in Zootaxa 4143 (1) on pages 41-42, DOI: 10.11646/zootaxa.4143.1.1, http://zenodo.org/record/26075
Dissomphalus clovisi Colombo & Azevedo, sp. nov.
No full textDissomphalus clovisi Colombo & Azevedo, sp. nov. (Figs 9, 143, 144) Description. Male. Head and mesosoma black; metasoma dark castaneous or black. Mandible with two apical teeth; clypeus broadly projected forward, median tooth ill defined; frons weakly coriaceous, punctate. Pronotal disc coriaceous. T2 without tergal process. Posterior hypopygeal margin weakly concave. Genitalia: paramere wide in dorsal view, apex serrate, invagination serrate in ventral view, smaller than basiparamere; cuspis very wide; digitus sickle-shaped; aedeagal ventral ramus smaller than dorsal body, base narrow, wide middle part, apex narrow, laminar; aedeagal dorsal body with two pairs apical lobes, apex weakly bifurcated in dorsal view, inner pair weakly membranous; basal bar wide; apodeme extending beyond genital ring. Female unknown. Remarks. This species is allocated in amplus species-group by having the tergal process absent. This species not is similar other of species-group. This species is mainly different because has the aedeagal ventral ramus with wide middle part and apex narrow; aedeagal dorsal body with apex weakly bifurcated and aedeagal dorsal body with basal bar wide. Material examined. Types: Holotype Ƌ, BRAZIL, E[spírito] S[anto]: Santa Teresa, Est[ação] Biol[ógica] de Santa Lúcia, 26–29.VIII.2004, arm[adilha] Malaise, Tavares & equipe col. (UFES). Paratypes: 1Ƌ, Santa Maria de Jetibá, Fazenda Paulo Seick, 20º02’S 40º42’W, 06–13.XII.2002, armadilha Malaise, Tavares & Azevedo e eq[uipe] col. (UFES). Etymology. The epithet clovisi is in allusion to the father’s second author name Clovis. Distribution. Brazil (Espírito Santo).Published as part of Colombo, Wesley D. & Azevedo, Celso O., 2016, Review of Dissomphalus Ashmead, 1893 (Hymenoptera, Bethylidae) from Espíri- to Santo, Brazil, with description of twenty-one new species, pp. 1-84 in Zootaxa 4143 (1) on page 40, DOI: 10.11646/zootaxa.4143.1.1, http://zenodo.org/record/26075
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