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Byblos, designated as a UNESCO World Heritage site, stands as one of Lebanon's most ancient urban centers, known for its expansive green spaces. However, ongoing urbanization threatens these valuable areas. This study uses a multi-faceted approach to evaluate the structure and landscape attributes of Byblos' urban and peri-urban forests (UPFs). Landscape canopy cover, diversity indices, forest structure, and a silhouette perceptual test were assessed across 24 streets in the city center, residential zones, and areas with heavy vehicular traffic. Findings reveal that 28% of Byblos' canopy cover is concentrated mostly in the northeastern region. Native tree species account for 30% of the total, and a notable variation in tree diversity exists among different land-use types (Shannon diversity index (H) was 1.02 for the city center, 1.35 for residential streets, and 0.64 for vehicular areas). Additionally, a normal J-shaped distribution of tree diameters was identified across all street types. This study highlights a correlation between tree silhouettes and visual preferences, with densely spreading canopies being favored. Residential trees demonstrate the highest structural diversity and varied blossoming seasons. This research represents the first investigation into the current state of urban forestry in Byblos and offers recommendations for sustainable management and planning strategies. [ABSTRACT FROM AUTHOR]

Byblos, designated as a UNESCO World Heritage site, stands as one of Lebanon’s most ancient urban centers, known for its expansive green spaces. However, ongoing urbanization threatens these valuable areas. This study uses a multi-faceted approach to evaluate the structure and landscape attributes of Byblos’ urban and peri-urban forests (UPFs). Landscape canopy cover, diversity indices, forest structure, and a silhouette perceptual test were assessed across 24 streets in the city center, residential zones, and areas with heavy vehicular traffic. Findings reveal that 28% of Byblos’ canopy cover is concentrated mostly in the northeastern region. Native tree species account for 30% of the total, and a notable variation in tree diversity exists among different land-use types (Shannon diversity index (H) was 1.02 for the city center, 1.35 for residential streets, and 0.64 for vehicular areas). Additionally, a normal J-shaped distribution of tree diameters was identified across all street types. This study highlights a correlation between tree silhouettes and visual preferences, with densely spreading canopies being favored. Residential trees demonstrate the highest structural diversity and varied blossoming seasons. This research represents the first investigation into the current state of urban forestry in Byblos and offers recommendations for sustainable management and planning strategies.

Behavioral testing in perceptual or cognitive domains requires querying a subject multiple times in order to quantify his or her ability in the corresponding domain. These queries must be conducted sequentially, and any additional testing domains are also typically tested sequentially, such as with distinct tests comprising a test battery. As a result, existing behavioral tests are often lengthy and do not offer comprehensive evaluation. The use of active machine-learning kernel methods for behavioral assessment provides extremely flexible yet efficient estimation tools to more thoroughly investigate perceptual or cognitive processes without incurring the penalty of excessive testing time. Audiometry represents perhaps the simplest test case to demonstrate the utility of these techniques. In pure-tone audiometry, hearing is assessed in the two-dimensional input space of frequency and intensity, and the test is repeated for both ears. Although an individual's ears are not linked physiologically, they share many features in common that lead to correlations suitable for exploitation in testing. The bilateral audiogram estimates hearing thresholds in both ears simultaneously by conjoining their separate input domains into a single search space, which can be evaluated efficiently with modern machine-learning methods. The result is the introduction of the first conjoint psychometric function estimation procedure, which consistently delivers accurate results in significantly less time than sequential disjoint estimators. [ABSTRACT FROM AUTHOR]

Background Several visual tasks have been proposed as indirect assays of the balance between cortical inhibition and excitation in migraine. This study aimed to determine whether daily measurement of performance on such tasks can reveal perceptual changes in the build up to migraine events. Methods Visual performance was measured daily at home in 16 non-headache controls and 18 individuals with migraine using a testing protocol on a portable tablet device. Observers performed two tasks: luminance increment detection in spatial luminance noise and centre surround contrast suppression. Results Luminance thresholds were reduced in migraine compared to control groups ( p < 0.05), but thresholds did not alter across the migraine cycle; while headache-free, centre-surround contrast suppression was stronger for the migraine group relative to controls ( p < 0.05). Surround suppression weakened at around 48 hours prior to a migraine attack and strengthened to approach their headache-free levels by 24 hours post-migraine (main effect of timing, p < 0.05). Conclusions Daily portable testing of vision enabled insight into perceptual performance in the lead up to migraine events, a time point that is typically difficult to capture experimentally. Perceptual surround suppression of contrast fluctuates during the migraine cycle, supporting the utility of this measure as an indirect, non-invasive assay of the balance between cortical inhibition and excitation. [ABSTRACT FROM AUTHOR]

Energy consumption has been a critical factor for mobile video applications. The quality of content delivery over wireless mesh networks consisting of such devices is also considered important. Existing energy-aware research and industrial effort focuses on reducing high-energy-consuming working periods of mesh devices at the expense of decreasing the quality of video content. This paper proposes AOC-MAC, an energy-quality-balanced solution, deployed at the medium access control (MAC) layer, which works in conjunction with an energy-aware routing algorithm for wireless mesh devices. The simulation and perceptual test results are also presented to investigate the performance of the proposed solution. In particular, the impacts of content delivery data rate, mesh network topology scale, and mesh device mobility are studied. Results demonstrate that AOC-MAC obtains up to 23% energy savings at roughly the same content delivery quality level in comparison with the IEEE 802.11s MAC protocol. [ABSTRACT FROM PUBLISHER]

Energy consumption has been a critical factor for video services on mobile devices. Existing energy-aware video delivery solutions focus on reducing the energy consumption at either networks or mobile devices, at the expense of decreasing video quality. This paper proposes E-Mesh, an energy-aware wireless routing algorithm which balances the need for energy saving with that of maintaining good quality of video content. E-Mesh is deployed at the network layer and works in conjunction with an innovative energy-aware MAC-layer duty cycle management scheme. Both simulation and perceptual testing were performed investigating the performance of E-Mesh. In particular, the impact of E-Mesh on content delivery data rate, network topology scale, and device mobility were studied. Results demonstrate that E-Mesh obtains up to 23% energy savings at roughly the same content delivery quality level, in comparison with the state-of-the-art IEEE 802.11s routing protocol. [ABSTRACT FROM PUBLISHER]

As continuing support of National Public Radio's Tomorrow Radio project, this paper presents results from a consumer study conducted with iBiquity's HD Radio codec. Forty participants judged the quality of the HD codec (HDC) at various bit rates, ranging from 16 kbps to 96 kbps. A range of musical and speech genres were tested. This study provides in-depth information intended to help broadcasters select optimal bit rates when HD Radio's 96 kbps data stream is shared between primary and supplemental channels. [ABSTRACT FROM AUTHOR]