The Institutional Origins of Inequality in Sub-Saharan Africa

This paper seeks to provide a political explanation for the unexpectedly high levels of inequality found in the African region today. There is much variation within the region, however the common history and structural factors suggests a distinctly African kind of inequality. The paper describes the recent literature on African inequality and examines the limitations of traditional explanations for inequality in Africa. Instead, it is argued that natural endowments in the region shaped the nature of colonial institutions, which in turn created the conditions for high levels of inequality. The author concludes that the surprisingly high levels of inequality in Africa can be understood as part and parcel of a process of class formation linked to processes of state building that have their origins in the economic institutions of the early colonial state. Colonialism favored, in relative terms, certain indigenous groups, which often inherited the state at independence. Insofar as political power has often been used to gain economic advantages during the postcolonial era, inequality has changed little over the course of the last forty years, despite the official focus on development and poverty alleviation by donors and governments alike

High definition H.264/AVC subjective video database for evaluating the influence of slice losses on quality perception

Prior to the construction or validation of objective video quality metrics, ground-truth data must be collected by means of a subjective video database. This database consists of (impaired) video sequences and corresponding subjective quality ratings. However, creating this subjective database is a timeconsuming and expensive task. There is an ongoing effort towards publishing such subjective video databases into the public domain. This facilitates the development of new objective quality metrics. In this paper, we present a new subjective video database consisting of impaired High Definition H. 264/AVC encoded video sequences and associated quality ratings gathered from a subjective experiment. This database can be used freely to determine impairment visibility or estimate overall quality of a video in the case of lost slices due to network impairments

The expansion of African legislatures threatens to undermine parliaments

The number of seats in national legislatures around the world rarely changes. Yet, in Africa, a substantial number of countries have regularly increased the size of their legislatures, particularly in recent years. New research suggests legislative expansion can be linked to the manipulation of executive branches, with Presidents finding it politically useful to expand African legislatures to weaken and/or control it

No-reference bitstream-based impairment detection for high efficiency video coding

Video distribution over error-prone Internet Protocol (IP) networks results in visual impairments on the received video streams. Objective impairment detection algorithms are crucial for maintaining a high Quality of Experience (QoE) as provided with IPTV distribution. There is a lot of research invested in H.264/AVC impairment detection models and questions rise if these turn obsolete with a transition to the successor of H.264/AVC, called High Efficiency Video Coding (HEVC). In this paper, first we show that impairments on HEVC compressed sequences are more visible compaired to H.264/AVC encoded sequences. We also show that an impairment detection model designed for H.264/AVC could be reused on HEVC, but that caution is advised. A more accurate model taking into account content classification needed slight modification to remain applicable for HEVC compression video content

US-Afrikapolitik: Bushs Vermächtnis und die Regierung Obama

"Als George W. Bush im Januar 2009 das Präsidentenamt verließ, schien allgemeine Übereinstimmung darüber zu herrschen, dass seine Afrikapolitik einer seiner wenigen Erfolge gewesen ist, da selbst harte Kritiker der Regierung dies widerwillig einräumen mussten. Tatsächlich stieg während seiner Amtszeit das Engagement der USA auf dem afrikanischen Kontinent sehr deutlich an. Allein die Entwicklungshilfe wurde verdreifacht. Das Erbe der Regierung Bush ist weit weniger positiv, als gemeinhin angenommen wird. Denn trotz der deutlichen Erhöhung der US-Entwicklungshilfe für Afrika, blieb die US-Afrikapolitik mit grundlegenden Mängeln behaftet, die sich unter Bush noch verschärft hatten und nun für die neue Politik von Obama/ Clinton eine erhebliche Belastung darstellen. Die Regierung Bush hat es versäumt, die US-Politik gegenüber Afrika strategisch klar und umfassend zu definieren; dieser fehlt nach wie vor strategische Kohärenz. Dabei hat sich die ohnehin schon vorhandene institutionelle und programmatische Zersplitterung der US-Afrikapolitik erhöht und die United States Agency for International Development (USAID) wurde weiter geschwächt. Die diplomatische Präsenz der USA in Afrika und die administrativen Kapazitäten des Afrikareferats in Washington sind besonders deutlich zurückgegangen. Demgegenüber hat der sicherheitspolitische Einfluss des Verteidigungsministeriums erheblich zugenommen. Aufgrund dieser institutionellen Schwäche der US-Afrikapolitik, der geringen strategischen Bedeutung Afrikas und der haushaltspolitischen Restriktionen angesichts der Wirtschafts- und Finanzkrise sind unter Obama kaum entscheidende Änderungen zu erwarten. Allenfalls kann der Schwerpunkt verschoben werden, weg von der sicherheitspolitischen Agenda und hin zu Multilateralismus, verknüpft mit einem diplomatischen Stilwandel - wobei ein Imagegewinn der USA in Afrika schon ein Erfolg wäre." (Autorenreferat

VIQID: a no-reference bit stream-based visual quality impairment detector

In order to ensure adequate quality towards the end users at all time, video service providers are getting more interested in monitoring their video streams. Objective video quality metrics provide a means of measuring (audio)visual quality in an automated manner. Unfortunately, most of the current existing metrics cannot be used for real-time monitoring due to their dependencies on the original video sequence. In this paper we present a new objective video quality metric which classifies packet loss as visible or invisible based on information extracted solely from the captured encoded H.264/AVC video bit stream. Our results show that the visibility of packet loss can be predicted with a high accuracy, without the need for deep packet inspection. This enables service providers to monitor quality in real-time

No-reference bitstream-based visual quality impairment detection for high definition H.264/AVC encoded video sequences

Ensuring and maintaining adequate Quality of Experience towards end-users are key objectives for video service providers, not only for increasing customer satisfaction but also as service differentiator. However, in the case of High Definition video streaming over IP-based networks, network impairments such as packet loss can severely degrade the perceived visual quality. Several standard organizations have established a minimum set of performance objectives which should be achieved for obtaining satisfactory quality. Therefore, video service providers should continuously monitor the network and the quality of the received video streams in order to detect visual degradations. Objective video quality metrics enable automatic measurement of perceived quality. Unfortunately, the most reliable metrics require access to both the original and the received video streams which makes them inappropriate for real-time monitoring. In this article, we present a novel no-reference bitstream-based visual quality impairment detector which enables real-time detection of visual degradations caused by network impairments. By only incorporating information extracted from the encoded bitstream, network impairments are classified as visible or invisible to the end-user. Our results show that impairment visibility can be classified with a high accuracy which enables real-time validation of the existing performance objectives

Assessing quality of experience of IPTV and video on demand services in real-life environments

The ever growing bandwidth in access networks, in combination with IPTV and video on demand (VoD) offerings, opens up unlimited possibilities to the users. The operators can no longer compete solely on the number of channels or content and increasingly make high definition channels and quality of experience (QoE) a service differentiator. Currently, the most reliable way of assessing and measuring QoE is conducting subjective experiments, where human observers evaluate a series of short video sequences, using one of the international standardized subjective quality assessment methodologies. Unfortunately, since these subjective experiments need to be conducted in controlled environments and pose limitations on the sequences and overall experiment duration they cannot be used for real-life QoE assessment of IPTV and VoD services. In this article, we propose a novel subjective quality assessment methodology based on full-length movies. Our methodology enables audiovisual quality assessment in the same environments and under the same conditions users typically watch television. Using our new methodology we conducted subjective experiments and compared the outcome with the results from a subjective test conducted using a standardized method. Our findings indicate significant differences in terms of impairment visibility and tolerance and highlight the importance of real-life QoE assessment

Subjective quality assessment of longer duration video sequences delivered over HTTP adaptive streaming to tablet devices

HTTP adaptive streaming facilitates video streaming to mobile devices connected through heterogeneous networks without the need for a dedicated streaming infrastructure. By splitting different encoded versions of the same video into small segments, clients can continuously decide which segments to download based on available network resources and device characteristics. These encoded versions can, for example, differ in terms of bitrate and spatial or temporal resolution. However, as a result of dynamically selecting video segments, perceived video quality can fluctuate during playback which will impact end-users' quality of experience. Subjective studies have already been conducted to assess the influence of video delivery using HTTP Adaptive Streaming to mobile devices. Nevertheless, existing studies are limited to the evaluation of short video sequences in controlled environments. Research has already shown that video duration and assessment environment influence quality perception. Therefore, in this article, we go beyond the traditional ways for subjective quality evaluation by conducting novel experiments on tablet devices in more ecologically valid testing environments using longer duration video sequences. As such, we want to mimic realistic viewing behavior as much as possible. Our results show that both video content and the range of quality switches significantly influence end-users' rating behavior. In general, quality level switches are only perceived in high motion sequences or in case switching occurs between high and low quality video segments. Moreover, we also found that video stallings should be avoided during playback at all times

Assessing the importance of audio/video synchronization for simultaneous translation of video sequences

Lip synchronization is considered a key parameter during interactive communication. In the case of video conferencing and television broadcasting, the differential delay between audio and video should remain below certain thresholds, as recommended by several standardization bodies. However, further research has also shown that these thresholds can be relaxed, depending on the targeted application and use case. In this article, we investigate the influence of lip sync on the ability to perform real-time language interpretation during video conferencing. Furthermore, we are also interested in determining proper lip sync visibility thresholds applicable to this use case. Therefore, we conducted a subjective experiment using expert interpreters, which were required to perform a simultaneous translation, and non-experts. Our results show that significant differences are obtained when conducting subjective experiments with expert interpreters. As interpreters are primarily focused on performing the simultaneous translation, lip sync detectability thresholds are higher compared with existing recommended thresholds. As such, primary focus and the targeted application and use case are important factors to be considered when selecting proper lip sync acceptability thresholds