bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrated Process Design for Two Robots Based Incremental Sheet Metal Forming
Authors: Kreimeier Dieter , Zhu Jun Hong , Laurischkat R.
Published: February 2012

With the use of two industrial robots, Roboforming is a dieless incremental forming process, which is developed by the Chair of Production Systems at the Ruhr-University of Bochum. Connected to a cooperating robot system, these two robots hold respectively a forming and a supporting tool. Suitable for rapid prototyping and manufacture of small batch sizes with low costs, this forming process is based on flexible shaping through the synchronous movement of two industrial robots. Different from other single point incremental forming (SPIF) methods, the supporting tool used here greatly increases the geometric accuracy and the limited draw angle. A new processing technology always needs the computer-aided planning and simulation, which could accelerate the whole process and also give users the possibility to analyse and improve the process. In this paper, the whole integrated process design is introduced. After the modelling of the target CAD geometry, a self-developed CAM solution is used to get both tools’ positions and orientations according to the points on the geometrical surface. Based on the different forming strategies used, the supporting tool can even be synchronously placed at different positions on the sheet backside. After the tool path planning, the paths are first inputted into a simulation environment, which is consistent with the settings in the pilot plant. The tool positions and each robot’s postures can be seen and validated during the simulation. Before the final forming experiment, the tool paths are also sent into another simulation model for the forming analysis with the use of FEM technology. With consideration of many real material properties like springback and the subsequent deformation, the formed CAD geometry from the simulation is compared with the target CAD geometry and the forming results can be forecasted.
A Self-Correcting Approach for the Bending of Metal Parts
Authors: Damerow Ulf , Borzykh Mikhail , Homberg Werner , Trächtler Ansgar
Published: February 2012

During the manufacture of metal parts, geometrical deviations can appear. The reasons for this can be a variation in the properties of the semi-finished product, or wear phenomena on the punch-bending machine itself or on the punch-bending tool. When geometrical deviations appear, the process parameters normally have to be adjusted manually. The choice of the most appropriate process parameters is currently based on the operator's experience. Unfortunately, this is a time-consuming and expensive procedure right at the early stages of a production scenario. In addition, the trend towards reduced part sizes with tight tolerances, made of high strength materials, is drastically increasing the requirements regarding the production process. In order to reduce the scrap rate and the setup time for production scenarios, it is necessary to implement corrective action during the process by means of a special control strategy. A self-correcting control strategy based on a closed-loop control approach is thus under development at the University of Paderborn. The first step in this strategy involved conducting simulations is to identify those process variables, e.g. the strength or the geometrical properties of the material, which have a significant influence on the process. Once correlations between input and output variables had been established, different self-correcting control strategies were set up. To validate the simulation and to test the quality of the self-correcting control strategies, a special experimental tool, mapping the most important bending operations, was constructed at the University of Paderborn. The experimental tool is equipped with an additional measurement device and can be operated on a universal testing machine. Finally, the self-correcting control strategies were tested under production conditions on the original tool in order to take any additional influences of the punch-bending machine into consideration. In this paper, recent investigations are presented that were conducted in a collaborative project at the University of Paderborn together with two industrial partners. The results of the correlation between the variables governing the process, the development of a suitable measurement method, and a first approach to a self-correcting control strategy are set out.
Punch Radius Influence on “Large Size” Hydroformed Components
Authors: Papadia Gabriele , Del Prete Antonio , Spagnolo Alessandro
Published: February 2012

Sheet metal hydroforming has gained increasing interest during last years, especially as application in the manufacturing of some components for: automotive, aerospace and electrical appliances for niche productions. Different studies have been also done to determine the optimal forming parameters making an extensive use of FEA. In the hydroforming process a blank sheet metal is formed through the action of a fluid and a punch. It forces the sheet into a die, which contains a compressed fluid. Many studies have been focused on the analysis of process and geometric parameters influence about the hydroforming process of a single product with main dimensions till to 100 mm. In this paper the authors describe the results of an experimental activity developed on two different large sized products obtained through sheet metal hydroforming. Different geometric and process parameters have been taken into account during the testing phase to study, in particular, the punch radius influence on the process feasibility. An ANOVA analysis has been implemented to study the influence of geometrical and process parameters on the maximum hydroforming depth. Through this work it has been possible to verify that in the hydroforming process of large size products geometry and, in particular, punch radius, are some of the main factors that influences the feasibility of the products. Different considerations can be made about the effects of the blankholder force and the fluid pressure on the maximum hydroforming depth. As further developments, the authors would perform a numerical study in order to enlarge the knowledge of the process design space to other possible values of the punch radius.
Warm Deep Drawability of Peak-Aged 7075 Aluminium Sheet Alloy
Authors: Sotirov Nikolay , Simon Peter , Chimani Christian , Uffelmann Dirk , Melzer Carsten
Published: February 2012

Aluminium has become the material of choice for lightweight design. Today medium strength 5xxx and 6xxx-series alloys are widely used in automotive sheet components, substituting conventional steel because of their superior strength to density ratios. The use of these alloys results in a reasonable ratio of cost per weight saving and a good compatibility with existing production techniques in terms of forming and joining. High-strength 7xxx-series (AlZnMgCu) alloys offer the potential for further light weighting, but formability at ambient temperature is severely limited without the employment of pre- and post- forming heat treatment processes. A promising approach to improve the formability of the peak-aged 7xxx aluminium alloys is to utilize warm forming at process temperatures below the material’s recrystallization temperature. Extensive research on formability is required to develop useful components of complex shapes out of this material. This study describes the material behaviour of a high-strength EN AW-7075 T6 aluminium alloy (e.g. AMAG TopForm® UHS) in the temperature range of the warm forming. For the isothermal simulation of a cross die shape part the material parameters such as flow curves, Lankford parameters and forming limit curves were obtained by experimental testing in the relevant temperature range. A comparison of the numerical simulation with the experimental results for the critical drawing depths for the heated cross die tool at three different temperatures shows good agreement. The results presented in this study demonstrate the potential of warm forming for the manufacturing of complex components made of peak-aged 7075 aluminium sheet alloy.
Influence of Scandium on Magnesium and its Structure-Property Correlation
Authors: Amal Rebin A.X. , Kumaran S. , Rao T. Srinivasa
Published: February 2012

Magnesium alloys are the most demanded lightweight structural materials for different engineering applications such as aerospace, automobile, electronics, etc. However, the high temperature properties of Mg alloys are not comparable with its competitor, the Al alloys. Mg alloys are not recommended beyond 120°C due to their poor creep and oxidation resistance. In order to improve the high temperature properties of the magnesium alloys, rare earth containing Mg alloys were developed. Among these alloys, Mg-Sc alloys were found to be very interesting which exhibits better high temperature properties. In the present work, magnesium-scandium alloy was fabricated through liquid metallurgy route under inert cover. The alloy was characterized by optical microscopy, X-Ray Diffraction (XRD), Differential Thermal Analysis (DTA) and hardness testing. The microstructural analysis reveals the α-Mg phase and the distribution of fine Mg-Sc intermetallic. It is observed from the DTA that the melting point of the base alloy has got enhanced by the addition of Sc. There is also an appreciable improvement in the hardness by the addition of Sc.
In Situ Synthesis of Cr2Nb Reinforced Copper Alloy by Liquid Metallurgy Route
Authors: Dhokey Narendra B. , Sarve Sriganesh N. , Lamsoge Harshanand A.
Published: February 2012

Cu-8Cr-4Nb alloy with high strength and high thermal conductivity have received a lot of attention over the last decades due to promising role in space application of rocket combustion chamber of reusable launch vehicle. In the present work, the copper alloy is synthesized in induction furnace by liquid metallurgy route wherein elemental powders of chromium and niobium was used added into premelted copper melt under argon atmosphere. The cast product is characterised for hardness, optical, SEM, EDS and XRD. It is possible to produce this alloy with reproducible average hardness of 135 VHN. The precipitate of Cr2Nb showed moderate distribution in and around the grain boundaries of copper with precipitate size varying from 1.33 μm to7.0 μm.
On the Possibility of Occurrence of Anisotropy in Processing of Cu-CNT Composites by Powder Metallurgical Techniques
Authors: Shukla Anoop Kumar , Nayan Niraj , Murty S.V.S. Narayana , Sharma S.C. , Mondal Kallol , Sinha Parameshwar Prasad
Published: February 2012

Copper - multiwall carbon nanotubes (MWCNT) composite was processed by powder metallurgical processing technique. Pure copper powder and MWCNT were mechanically alloyed by high energy milling to produce Cu-MWCNT composite powder. The composite powder was subsequently consolidated by vacuum hot pressing. Characterization studies were conducted along axial (hot pressing direction) and radial (transverse) directions. Microstructural observations of the processed composite revealed random distribution of MWCNT in axial direction and aligned distribution in radial direction. The structure property correlation was established and it revealed certain degree of anisotropy in mechanical and electrical properties of the composite.
Studies on the Effect of Graphite Content on Hardness and Electrical Resistivity of Silver-Graphite Composites
Authors: Khanra G.P. , Girikumar S. , Gangadhar De , Mishra Deepak K. , Saravanan T.T. , Dineshraj S. , Sharma S.C.
Published: February 2012

Silver-Graphite composites are attractive materials for electro-mechanical devices to provide noise free rotation between mating surfaces with minimum contact voltage drop. In the present study, the composite was processed through Powder Metallurgy (P/M) route considering that the constituent elements have divergent physical properties without any metallurgical bond between them. The developed composites were evaluated for hardness, electrical resistivity, contact voltage and density. This paper presents a correlation between hardness and electrical resistivity against volume fraction of graphite added, through linear regression which has clearly indicated that the said properties of the composites are highly dependent on the volume fraction of graphite. The hardness and electrical resistivity of the composites were found to obey the relations given below (i) Log H=1.522 + 1.667 Log (1-fg), (ii) 32.36 Log (ρ0/ρ) =1 + 83.74 Log (1-fg), where H is hardness of composites, ρ0 is electrical resistivity of pure silver, ρ is electrical resistivity of composites and fg is the volume fraction of graphite.
Synthesis and Characterization of In Situ AlN Reinforced Magnesium Matrix Composites
Authors: Sukumaran Suseelammaa Sreeja Kumari , Subramonia Pillai Uma Thanu , Prasanth Sujayakumar , Pai Bellampettu Chandrasekhar
Published: February 2012

In situ Mg-AlN composite has been synthesized by nitrogen gas bubbling method. The morphology of the particles is found to be hexagonal by SEM. The size of the AlN particles is found to be in the range from nano, submicron to a few microns. XRD analysis of the samples confirms the formation of AlN in the melt. Further, the grain size of the magnesium matrix has been reduced by the presence of AlN particles. Hardness of the composite is significantly increased in the particle rich area due to the presence of hard AlN particles.
Modeling the High Temperature Deformation Behaviour of a near Alpha Titanium Alloy with Bi-Modal Microstructure
Authors: Balasundar I. , Raghu T. , Kashyap B.P.
Published: February 2012

The high temperature deformation behaviour of near alpha titanium alloy IMI834 with a bimodal microstructure has been evaluated by carrying out isothermal compression tests over a range of temperature and strain rate. The optimum thermomechanical processing (TMP) parameters i.e., temperature, strain rate that can be used to produce various aeroengine components were identified using dynamic materials modeling (DMM). Using kinetic analysis, a unified constitutive equation that describes the deformation behavior of the material in the selected temperature - strain rate regime has been established and the deformation mechanisms operating in the material were identified.
Effect of Welding Processes (GTAW & EBW) and Solutionizing Temperature on Microfissuring Tendency in Inconel 718 Welds
Authors: Agilan M. , Krishna S. Chenna , Manwatkar Sushant K. , Vinayan E.G. , Sivakumar D. , Pant Bhanu
Published: February 2012

Inconel 718 is widely used superalloy in the Indian space program for high temperature application. Some of the newer applications envisage use of this alloy in very critical high pressure oxygen carrying vessels. The alloy is frequently used in welded condition which requires extensive characterization of various types of welds viz Electron beam welding (EBW) and Gas tungsten arc welding (GTAW). In many cases the weldability of Inconel 718 is found to be limited by microfissuring phenomenon in the weld heat affected zone. Microfissures are fine intergranular cracks and their severity strongly depends on pre-weld solution treatment temperature (grain size), weld heat input and concentration of impurities (B, P and S) in the base metal. In the present work, a study was undertaken to compare the microfissuring tendency in EBW and GTAW processes using two pre-weld solution treatment temperatures. The samples were solution treated at 970°C and 1050°C to generate different grain sizes. Amount of heat input and cooling rate were calculated since they are known to affect the microfissuring and an effort was made to understand their role on the microfissuring. It was observed that microfissuring susceptibility is more at coarser grain size. Severity is more in EBW. The reasons for this phenomenon have been discussed in this paper correlating microfissuring with microstructures and other factors. Procedures to achieve minimal microfissuring during welding have also been brought out.
Laves Phase Control in Inconel 718 Weldments
Authors: Manikandan S.G.K. , Sivakumar D. , Kamaraj M , Rao K. Prasad
Published: February 2012

The detrimental laves formation in fusion zone during welding of Inconel 718 is controlled with compound current pulsing technique along with helium shielding gas. Also solid solution filler wire is used to minimize the niobium segregation. Welds were produced in 2mm thick sheets by GTA welding process and subjected to the characterization techniques. The results show, refined fusion zone microstructure, reduced amount of laves phase, minimum niobium segregation and softer fusion zone in the as welded condition.
Laser Beam Welding of Aluminium: Process Optimisation to Achieve Hermetic Sealing for Electrochemical Energy System Containers
Authors: Mercy T.D. , Sharma Rahul , Kaladharan V.F. , Kamalakaran K.P.
Published: February 2012

Hermetic sealing is essential for long cycle life and calendar life of Lithium ion cells. Ingress of moisture and leaking of electrolyte in Lithium ion cells deteriorates the electrochemical performance. Nickel coated mild steel, Stainless steel, Aluminium and its alloys are generally used as case material. Pure Aluminium and Aluminium alloys are used to improve energy density of Lithium ion cells. High heat input is required for aluminium to obtain a sound weld because of the high thermal conductivity of the Aluminium. High heat input results in increased heat affected zone (HAZ) and transfer of heat into internal components during welding. Laser Beam Welding (LBW) results in very narrow heat affected zone (HAZ) and it is possible to have dissimilar metal welding. In the present work, experimental studies conducted to optimise the laser beam welding parameters for welding of Li-ion AA3003 cell case to lid without defects viz porosity and required weld strength. Hermeticity and strength of the weld bead were analysed in detail to ensure the adequacy of the process. It has been demonstrated that laser beam welding is a viable process for joining of cell case to its cover.
Effect of Plasma Electrolytic Surface Treatment on the Corrosion Characteristics of the Ti-6Al-4V in Acidic, Industrial and Marine Environments
Authors: Suresh S. , Pavankumar K. , Rameshbabu N. , Venkateswarlu K.
Published: February 2012

Titanium and its alloys find wide range of applications in aerospace, marine and automobile industries due to their excellent properties like high strength to weight ratio and good mechanical behaviour. Accordingly, the structural parts made of these alloys are being exposed to different corrosive environments. Therefore, the electrochemical stability of these structural parts needs to be significantly improved for their extended life time and effective functioning. The objective of the present work is to examine the effect of plasma electrolytic surface treatment in improving the corrosion resistance of Ti-6Al-4V in simulated acidic (0.5M H2SO4), marine (3.5% NaCl) and sulphur containing industrial (0.5M Na2SO4) environments. PEO is a relatively new technique for producing ceramic coatings on light metal alloys by employing higher voltage and current than anodizing. The Ti-6Al-4V was surface treated by plasma electrolytic oxidation (PEO) technique for 12 min under optimized conditions of electrical processing parameters and electrolyte chemistry. The logically selected electrolyte system consisting of 10 g of tri-sodium ortho phosphate (Na3PO4.12H2O), 2 g of sodium meta silicate (Na2SiO3.9H2O) and 2 g of potassium hydroxide (KOH) in 1 L of double distilled water was employed. The decisively optimized electrical parameters were fixed as 75% for the duty cycle, 1500 Hz for the pulse frequency and 0.1 A/cm2 for the current density. The phase composition of the resulted coating was analyzed by the X-ray diffraction (XRD) technique. The coating thickness and the elemental composition of the coating were assessed using a scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS). The corrosion characteristics were determined by potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) measurements. The XRD results demonstrated that the resulted coatings consisted of both anatase and rutile phases. The SEM results showed a coating thickness of about 15 µm and a canal like surface morphology with inter-connected open pores over the coating surface. The potentiodynamic polarization test results, in general, showed a minimum of about two orders of magnitude improvement in the corrosion resistance of the treated Ti-6Al-4V compared to that of the untreated in all the three corrosive environments. The EIS test results exhibit comparatively higher AC impedance and higher bode angle over the entire frequency range indicating an improved corrosion resistance of the surface treated Ti-6Al-4V. Thus the plasma electrolytic surface treatment with optimized process parameters, made the Ti-6Al-4V electrochemically stable by significantly improving its corrosion resistance in all the three environmental conditions.
Investigations on Ni-Ti-Al Ohmic Contacts Obtained on P-Type 4H-SiC
Authors: Laariedh Farah , Lazar Mihai , Cremillieu Pierre , Leclercq Jean Louis , Planson Dominique
Published: February 2012

Transfer Length Method (TLM) based-structures were fabricated on 0.8 µm-thick epitaxial p-type Silicon Carbide (4H-SiC) layers. TLM mesas were defined by a 2 µm height using an SF6/O2 reactive ion etching. TLM metal patterns were obtained by a lift-off procedure and electron beam deposition of Ni, Ti, Al and Pt. The patterned samples were annealed in Argon ambient at temperature ranging from 700°C up to 1000°C in a RTA furnace with a rapid heating ramp (up to 50°C/s) to complete the ohmic contact with the p-type SiC layer. Specific contact resistances were extracted from current/voltage measurements. To identify and follow the profile evolution of constituting element in the contacts and at the SiC/contact interface, the ohmic contacts were characterized using Secondary Ion Mass Spectrometry and Energy-Dispersive X-Ray spectroscopy before and after annealing. Ohmic contacts are obtained only for the Ni/Ti/Al and Ni/Ti/Al/Ni stacking layers and not for the Ti/Al/Ti/Ni and Ti/Al/Ti/Pt/Ni compositions. The specific contact resistance of Ni/Ti/Al/Ni stacking layers was observed to decrease from 2.7×10-4 Ω.cm2 at 700°C and 6.3×10-5 Ω.cm2 at 750°C to a minimal value of 1.5×10-5 Ω.cm2 at 800°C. Ohmic contacts are obtained with a reproducibility of 80 %.
Magnesium Alloys a Promising Option as Protection Materials
Authors: Ahmad Iram Raza , Shu Dong Wei
Published: February 2012

Lighter yet stronger magnesium alloys have become very attractive for applications where materials undergo larger strains such as crash events in vehicles and planes, penetration of projectiles in personal body armour and vehicle armours. Excellent combination of light weight and good mechanical properties put magnesium alloys ahead of other structural materials in applications where high specific properties are required. It is well anticipated that magnesium alloys have enormous potential as a whole or a part of protective structures.
Rate-Dependent Constitutive Modeling of Polymer Subjected to Dynamic Loading
Authors: Yuan Jian Ming , Ma Jan , Tan Geoffrey E.B. , Liu Jian Fei
Published: February 2012

This paper proposes an effective and systematical method to obtain reliable rate-dependent material models used in FEM simulation for polymers. Compressive stress-strain curves of two types of polymer are obtained at different strain rates. Rate-dependent elastic-plastic models are applied to describe the observed rate-dependent behaviors, whereby the input data of material model are determined from the test data obtained. Verification of the material models is proposed via comparing FEM simulation with test data of quasi-static tension tests and dynamic compression tests of different strain rates.
Assessment of Mechanical and Corrosion Properties of GTA Welded Monel 400 Plates Exposed to Air Oxidation at 700°C
Authors: Devendranath Ramkumar K. , Narayanan S. , Arivazhagan N. , Kashyap Raunak , Rajiv Sushanth S , Ravi Teja V
Published: February 2012

Oxidation and hot corrosion are serious problems in marine and power plants. Hence understanding the corrosion behavior of weldment at elevated temperatures has become the vital scientific investigation nowadays. Monel 400 is one of the widely used high temperature material that can obviate the problems. The objective of the present investigation is to study the mechanical properties and corrosion behaviour of gas tungsten arc welded Monel 400 plates subjected to air oxidation. It was observed from the tensile tests that fracture occurred at the weld region. In addition, cyclic air oxidation tests were performed on the different regions of welded Monel 400 at 700°C. It was found that corrosion was found to be extremely severe on the weld zone after exposed to 50 cycles. The corrosion products were characterized using the combined techniques of optical microscopy, XRD, SEM/EDAX analysis.
eThekwini Municipality’s intranet for augmenting knowledge–sharing in the organisation
Authors: Averweg Udo R.
Published: February 2012

Background: The age of technology, where information and knowledge perform important roles in the organisational context, creates an opportunity for local government organisations (such as metropolitan municipalities) in South Africa to support knowledge–sharing. One such technology that supports knowledge–sharing is an intranet. If an intranet is not effectively managed, knowledge–sharing in an organisation shall not be augmented.Objective: To investigate whether or not an intranet augments knowledge–sharing in the selected organisation of eThekwini Municipality.Methods: In this study a quantitative research approach was adopted.Results: The results of this survey suggest that firstly the intranet appears to be at a medium maturity level; secondly, whilst there is information sharing, the intranet does not appear to be effective as a knowledge–sharing structure; and thirdly there appears to be scope for improvement of the content on the intranet. The implication thereof is that eThekwini Municipality’s recently formed Municipal Institute of Learning (MILE) may be ideally poised to address the identified shortcomings.Conclusion: Intranet technology plays an important role in an organisation by enabling the effective acquisition, sharing and presentation of knowledge. Because of this an intranet must be effectively managed to readily augment knowledge–sharing in the organisational context of local government organisations (such as metropolitan municipalities) in South Africa.
Interface entre saúde mental e a economia popular solidária
Authors: Nunes Gorza Anelise , Cei Santos Amanda , Patrocínio Ribeiro Andrea
Published: February 2012

The experience reported in this paper takes place through the extension project Integrated Actions in Mental Health: building intervention and interaction strategies in the system of mental health of Cariacica. The group follows the public politics of mental health and the principles of the National Politics of Solidary Economy. It aims at producing a form of collective, equitable and solidarity work in which the income can promote sustainability and self-management of the group, having as facilitators social workers, psychologists and psychology students. It’s possible to perceive the social, economic, cultural and therapeutic development of the members. Work through cooperation and solidarity provides the breakdown of stigma and production of new forms of society acting towards madness.
Evolution of marine storminess in the Belgian part of the North Sea
Authors: Van den Eynde D. , De Sutter R. , Haerens P.
Published: February 2012

Abstract. Severe storms have affected European coast lines in the past but knowledge on changes in storminess for the last decades is still sparse. Climate change is assumed to be a main driving factor with the potential to induce changes on the intensity, duration and frequency of powerful marine storms, including a long-term influence on peak wind speeds, surges and waves. It is, therefore, important to investigate whether in the last decades changes in the magnitude of storms, their duration and frequency could be observed. Understanding trends in storminess in the last decades will help to better prepare coastal managers for future events, taking into account potential changes on storm occurrence and magnitude to improve planning of mitigation and adaptation strategies. The purpose of this study was to focus on the evolution of extreme wind conditions, wave height and storm surge levels in the North Sea Region, especially in the Belgian part of the North Sea (BPNS). Based on the analysis performed it is concluded that no clear trend can be observed for the occurrence of significant increasing extreme wind speeds over the BPNS. Furthermore, one can conclude that not enough scientific evidence is available to support scenarios with increased wave height or storminess.
Interannual response of global ocean hindcasts to a satellite-based correction of precipitation fluxes
Authors: Storto A. , Russo I. , Masina S.
Published: February 2012

Abstract. We present a methodology to correct precipitation fluxes from the ECMWF atmospheric reanalysis (ERA-Interim) for oceanographic applications. The correction is performed by means of a spatially varying monthly climatological coefficient, computed within the period 1989–2008 by comparison between ERA-Interim and a satellite-based passive microwave precipitation product. ERA-Interim exhibits a systematic over-estimation of precipitation within the inter-tropical convergence zones (up to 3 mm d−1) and under-estimation at mid- and high- latitudes (up to −4 mm d−1). The correction has been validated within eddy-permitting resolution global ocean hindcasts (1989–2009), demonstrating the ability of our strategy in attenuating the 20-yr mean global EMP negative imbalance by 16%, reducing the near-surface salinity fresh bias in the Tropics up to 1 psu and improving the representation of the sea level interannual variability, with an SSH error decrease of 8%. The ocean circulation is also proved to benefit from the correction, especially in correspondence of the Antarctic Circumpolar Current, where the error in the near-surface current speed decreases by a 9%. Finally, we show that the correction leads to volume and freshwater transports that better agree with independent estimates.
The Scandal of Real Estate Bankruptcies: The Royal Boxes of Oruro and Carangas, 1784-1804
Authors: Gavira Márquez María Concepción
Published: February 2012

The aim of this research paper is to critically analyze the effectiveness of the Bourbon Reforms in the Viceroyalty of Río de la Plata. In 1802 the chaotic situation and multiple failures of the Royal Treasury led the Crown to send a visitor to the Viceroyalty. It had been denounced as scandalous the bankruptcies that took place in much of the Charcas’ Cajas Reales: La Paz, Oruro, Carangas. This work deals with bankruptcies occurred in the two Cajas located in the mining centers of Oruro and Carangas during the last two decades of the Eighteenth-century, a period associated with the Bourbon reforms and its success in the taxation of the of the Spanish colonies in America.
Pensando el “diálogo académico” norte/sur
Authors: Krueger Chris
Published: February 2012

This work approaches the complex relation between North American institutions dedicated to the production of knowledge on Bolivia and its homologous Bolivians, emphasizing the fact that nowadays in Bolivia not only an immense intellectual wealth totally established exists, but also a field of emergent knowledge whose reflections and challenges deserve a diffusion in the north. To authorize in the north the theoretical potecial of the debates generated in Bolivia would make the knowledge produced on Bolivia a lot more dynamic and responsible. Inversely, I will also discuss the importance to initiate in Bolivia studies that will lead to understand the complexity of the institutions and societies of the north, that are not neither homogenous nor static, less still automatically reproductive of imperialism.
Ruwirtu Chuqi Kanki, Kristina Kiswirt Qhispi. Aymaranakan sarantayirinaka: Uraq ayllunak ch’axwa
Authors: Ari-Chachaki Waskar
Published: February 2012

Book Review / Reseña
Terracotta Imagery in Israel and Judah under the Divided Monarchy (c. 925–586 bc)
Authors: Moorey P. R. S.
Published: February 2012

This chapter discusses Israelite goddesses, terracotta figurines, and the emergence of free-standing terracottas in Israel and Judah. It then provides two key contexts between Cave 1 (Ophel) in Jerusalem (Judah) and area E-257 in Samaria (Israel). Finally it looks at the repertory of Judean terracottas in the 8th and 7th centuries bc.
Geographers and the fragmented city
Authors: Peach Ceri
Published: February 2012

By the end of the twentieth century, the focus of geography had narrowed, its content had become less disciplined by spatial concerns, and its subject matter had become fragmented. Geographers were writing about small, personal subjects: about identity and positionality, about statues and monuments. How and why did this come about? Perhaps because both the urban geography of Britain underwent massive change and the way in which British geographers thought about cities was revolutionised. This change in urban geography in Britain during the twentieth century can be attributed in part to the fact that the geography of British towns has changed significantly over the period. This chapter focuses on geographers and the fragmented city, starting with a brief account of the urban change and then moving on to discuss the shifts within the philosophy of geography. It also examines urban social segregation, with emphasis on race, ethnicity, gender and sexuality.
Introduction—from Staatsrechtslehre to Behemoth
Authors: Kelly Duncan
Published: February 2012

This is a book about how conceptions of the modern state, politics and the political were understood, developed and modified by Max Weber (1864–1920), Carl Schmitt (1888–1985) and Franz Neumann (1900–1954) during the period 1890 to 1945 in Germany. It is an attempt to outline their criticisms and modifications of a broad, peculiarly German tradition of Staatsrechtslehre, or state-legal theorizing. The predominantly legalistic nature of this type of thinking forms both the background to, and the bases of, the understandings of the modern state and politics found in their writings. Yet, all three writers argued that such thinking could not adequately adapt to the problems raised by an era of mass-based politics. Tracing the reasoning behind their movement away from this broad tradition of Staatsrechtslehre therefore provides an overarching context for this work.
Conclusion
Authors: Constantine Mary-Ann , Porter Gerald
Published: February 2012

This chapter discusses the major conclusions that can be gathered from the previous chapters. It determines that fragments and fragmentary styles are reinvented with each literary generation. For the writers in the early twentieth century, broken forms have been considered as a way to convey absences and emptiness, and even the breakdown of communication. The chapter also shows how the fragment has become an emblem of the discontinuous and rapidly changing nature of the postmodern condition. Stripped down songs, folk-song scholarship, and other important concepts are discussed and reviewed.
The Prosopography of the Later Roman Empire: Yesterday, Today and Tomorrow
Authors: Mathisen Ralph W.
Published: February 2012

Several lessons have been leant from the three volumes of PLRE. The scholarly response suggests that the most sought-after attributes of any prosopographical catalogue are clearly formulated and stated criteria for inclusion, consistency in the application of the criteria, and completeness of coverage. In sum, PLRE has caused people to rethink many of the ways in which they look at late antiquity. The development of the material demonstrates the growing diversity of the Mediterranean world: PLRE by PLRE III, one has a massive array of eastern and western non-Romans both within and outside the imperial frontiers. As a result of its increasing inclusivity, PLRE became more of a secular PLA than a PLRE. Overall, this chapter concludes that PLRE has become the one work that must be on the shelves of anyone who proposes to make a comprehensive study of the late antique world.
Prosopography and Byzantine Identity
Authors: Magdalino Paul
Published: February 2012

This chapter reflects on the contribution of prosopography to Byzantine studies during the second half of the twentieth century. To get it right, the set of identities has to be comprehensive, each identity has to be complete and correct, and its points of contact with other identities have to be clearly visible. Prosopography retrieves and labels the bits, then it boxes the kits, from which past identities are assembled and interpreted scientifically. While it may not be committed to delivering finished solutions, it lays out the steps by which they are reached, through its absolute commitment to the principles which make it a distinct form of historical science: that every piece of historical data should be related to an identifiable historical person, that multiple identities should not be confused, single identities should not be multiplied and collective identities should always be defined in terms of connections between individuals.
The Contribution of Papyri to the Prosopography of the Ancient World: Evaluation and Prospects
Authors: Carrie Jean-Michel
Published: February 2012

Some are familiar with the dictum often attributed to Mommsen at the end of the nineteenth century, according to which papyrology was destined to become the leading discipline of ancient history in succession to epigraphy, which had previously been dominant. During the century in which this new branch of knowledge of antiquity has been in existence, the contribution of papyri and ostraca to the documentation of ancient societies has justified the hopes thus placed in it. It is all the more surprising, then, to note that among historians there persists a certain failure to appreciate this contribution and a reluctance to exploit it. The truth is that papyri share the same fragmentary, random and lacunose character that is a feature of the majority of documentary sources available to us for the study of the ancient world.
Seals and the Prosopography of the Byzantine Empire
Authors: Seibt Werner
Published: February 2012

For certain periods of the middle Byzantine era, seals, especially lead seals (molybdoboulla), played much the same role as do inscriptions for the Roman epoch. This chapter begins by stressing the impressive size of the epigraphic material. The number and importance vary through the centuries, but even from the most casual glance, one gets the impression that in two respects, both important to prosopography, developments reached their summit in the eleventh century: the number of seals, and the data that they offer. Working with such material involves at least three steps: reading, dating and interpretation.
: The Critique of Individualism
Authors: Ryan Alan
Published: February 2012

This chapter focuses on the thought that ‘rational, economic man’ may be a useful figment of the economists’ imagination but is not a useful figment of the social and political theorist’s. After some remarks about the strength of individualism in British political thought, the chapter discusses the post-1945 debate over the virtues of ‘methodological individualism’ and its supposed political implications. The argument then begins in earnest with the late nineteenth-century and early twentieth-century Idealist critique of the ‘narrow individualism’ that Idealists believed underlay utilitarianism and earlier forms of liberalism. The discussion also cites some British contributions to the Marxist critique of rational economic man, and ends with a very short discussion of communitarianism.
: Pressure Groups and Parties
Authors: Richardson Jeremy
Published: February 2012

The central paradox in reviewing the contribution of British political scientists to the understanding of these intermediary institutions is that both the number of scholars and the output have been considerable, yet the international impact has been relatively modest. Two explanations seem plausible. First, with a few notable exceptions, the centre of gravity of these studies has coincided with the centre of gravity of British political science as a whole – it is largely atheoretical in its research style. A second possible explanation is that studies in these fields have tended to focus on activities (of groups and social movements) or on office-holding (parties) and have been much less interested in power as a concept. Relatively little is known about the effects that this activity has on outcomes in terms of public policy or the distribution of power in society.
: Electoral Systems, Elections and Public Opinion
Authors: Miller William L.
Published: February 2012

Throughout the twentieth century, the content and focus of British research on elections and public opinion was influenced by the changing political agenda of the day, but its quantity and style were more influenced by economic and technical factors: the increasing availability of funds and rapid advances in the technology of research, particularly from the 1960s onwards. What distinguished the end of the century from the start was not so much the accumulated store of knowledge about electoral behaviour and public opinion, important though that was, but an ability to investigate quickly, easily, frequently, and in great detail, which simply did not exist at the start. Electoral research on Britain and by Britons was fully up to international standards in concept and method and was well integrated with research elsewhere.
: The Analysis of British Political Institutions
Authors: Marshall Geoffrey
Published: February 2012

The analysis of British political institutions in the twentieth century has not emerged solely from the writing of textbooks by political scientists. The genesis of general thinking about the government of the United Kingdom is to a lesser degree the product of professional reflection than is the development of theories about comparative government. It evolves more directly from the political process itself and from the controversies about government that government itself generates. This chapter discusses the powers of Parliament, the nature of cabinet government, the accountability of ministers, the dignified institutions, the re-modelling of Dicey’s institution, political institutions and public inquiry, and theory and analysis in political institutions.
Competition Policy: From Centrality to Muddling Through?
Authors: Lodge Martin
Published: February 2012

Competition policy has been said to lie at the heart of the German social market economy and to have been a key influence on the EC competition regime. This chapter assesses the impact of Europeanization on the competition law policy domain in the light of earlier claims that suggest a marginalization of the Federal Cartel Office. The question is pursued through three case studies that involve three different Europeanization dynamics: those of domestic assimilation of EU policy provisions, of informing policy change at the EU level, and of ‘collision’ between national and Commission policy preferences. The cases cover three distinct policy issues: the Europeanization of domestic competition law, attempts to shape changes to the EC regime's Regulation 17/62, and efforts of the DG Competition to prohibit the fixed-book price agreement between Austria and Germany. While those cases leading to domestic policy change suggest a considerable degree of national ‘resilience’, the example of ‘informing EC policy change’ points to the declining influence of the German approach vis-à-vis other national competition law experiences, Commission preferences, and changing competition policy ‘ideas’.
Foreign and Security Policy: On the Cusp Between Transformation and Accommodation
Authors: Miskimmon Alister , Paterson William E.
Published: February 2012

Foreign and security policy-making within Germany represents a singular policy area. From its inception it emerged into an already existing multilateral framework under the conditions of semi-sovereignty. In addition, this policy area is dominated within Germany by a comparatively small number of policy élites, with little or no sectoral interests outside that of central government to push for increased co-operation. Nonetheless, central to this chapter is the question of why there has not thus far been a far-reaching Europeanization of policy, despite Germany's apparent deep commitment to European integration and EU foreign and security policy co-ordination. German foreign and security policy finds itself on the cusp between accommodation and transformation and has not progressed further as a result of internal and external factors that continue to define German security policy as a distinctive case.
Introduction
Authors: Brady Michael , Bowman Alan K.
Published: February 2012

This book is a result of the joint research project on the image enhancement of ancient documents. It brings together researches and projects in such way techniques and results could be discussed in a way which would capitalize the possibilities of cross-fertilization, of generalizing techniques from a category of object or problem to another, and encourage people to think laterally and in interdisciplinary way on advancing techniques of imaging and visual understanding of objects under study. It aims to instil awareness of the extent to which scientific contributions are thinking about subjectivity of interpretation, visual cognition, and the need to improve methods of presenting evidence in ways which feed their scientific thinking and encourage genuine innovation of approach to developing methods of image enhancement. The chapters of this volume offer a wide range of treatment of artefacts and of techniques, many of which could be applied to a broader range of materials. While this volume did not include all scientific techniques and artefacts, it includes all artefacts which require three-dimensional (3D) imaging techniques. In this volume, the main themes are: imaging documents, laser imaging, 3D reconstructions, reconstruction of faces and depth perception from relief.
Wooden Stilus Tablets from Roman Britain
Authors: Bowman Alan K. , Tomlin Roger S. O.
Published: February 2012

The imaging of ancient document papers presents several challenges, the nature of which is determined by the character of the text, the material on which it is written and the state of preservation. This chapter talks about the struggle to read and interpret Latin manuscripts from Roman Britain. These manuscripts come mainly in three forms: texts written in ink on thin wooden leaves, texts inscribed with metal stylus on wax-coated wooden stilus tablets, and texts incised on sheets of lead. This chapter focuses on the problems of imaging and signalling process of the texts found on the Vindolanda stilus tablets. These problems in interpreting ancient texts arise from the two identifiable sources of difficulty. The first one is the problem of seeing and identifying, in abraded and damaged documents what is aimed to be read. The second is the problem arising from the character of the text itself which determines the ability of the reader to decipher and interpret it.