Syntactic Complexity in Reading Comprehension: An Eye-Tracking Study of Text Processing Among Bilinguals and Monolinguals

For Chinese students, studying in a country with different cultural components and language structures is challenging. Compared to English, the Chinese prefers shorter and simple sentence structure and allows for two sentences to be stated side by side. Different sentence structures in Chinese may influence native-Chinese readers’ understanding of English sentences and even a whole text. This exploratory study examined whether there were any differences between English monolingual and Chinese-English children while reading varied English texts with simple or complex structures at different reading difficulty levels. This study explored the differences across texts and readers, as well as the possible effect of first-language transfer on text comprehension behavior. Behavioral and eye-tracking data, including accuracy of true/false questions, reading speed, and first fixation duration were analyzed. For true/false questions, both groups answered the questions with sufficient accuracy, indicating basic understanding of the brief passages. For reading speed and first fixation duration, as expected, monolinguals read faster with shorter fixations than bilinguals across all passages and monolinguals revealed faster reading speed for easy passages than for hard passages. However, no difference was found between easy and hard passage reading for bilinguals, which was surprising, suggesting that vocabulary difficulty may not have influenced reading speed. Additionally, the findings that no differences for reading difficulty or syntactic complexity between or within each group in first fixation duration were unexpected. To examine whether participants’ offline behavioral test scores (i.e., language, reading and cognitive capacity) influenced the relationship between first fixation duration and syntactic complexity or reading difficulty, the offline behavioral test scores were added into analysis. According to the results, monolinguals performed expectedly with stronger influence of reading and cognitive capacities on complex structure passages. However, bilinguals appeared to attend to the simple structure passages as expected, but not complex passages. Results suggest that English complex structures may have been too difficult for bilinguals to apply reading knowledge or cognitive ability for text processing or bilinguals were less responsive to the syntactic complexity due to their first-language transfer

Achromatic and Athermal Design of Aerial Catadioptric Optical Systems by Efficient Optimization of Materials

The remote sensing imaging requirements of aerial cameras require their optical system to have wide temperature adaptability. Based on the optical passive athermal technology, the expression of thermal power offset of a single lens in the catadioptric optical system is first derived, and then a mathematical model for efficient optimization of materials is established; finally, the mechanical material combination (mirror and housing material) is optimized according to the comprehensive weight of offset with temperature change and the position change of the equivalent single lens, and achieve optimization of the lens material on an athermal map. In order to verify the effectiveness of the method, an example of a catadioptric aerial optical system with a focal length of 350 mm is designed. The results show that in the temperature range of −40 ℃ to 60 ℃, the diffraction-limited MTF of the designed optical system is 0.59 (at 68 lp/mm), the MTF of each field of view is greater than 0.39, and the thermal defocus is less than 0.004 mm, which is within one time of the focal depth, indicating that the imaging quality of the optical system basically does not change with temperature, meeting the stringent application requirements of the aerial camera

Optimization Method for Low Tilt Sensitivity of Secondary Mirror Based on the Nodal Aberration Theory

The optical system that combines imaging and image motion compensation is conducive to the miniaturization of aerial mapping cameras, but the movement of optical element for image motion compensation will cause a decrease in image quality. To solve this problem, reducing the sensitivity of moving optical element is one of the effective ways to ensure the imaging quality of aerial mapping cameras. Therefore, this paper proposes an optimization method for the low tilt sensitivity of the secondary mirror based on the Nodal aberration theory. In this method, the analytical expressions of the tilt sensitivity of the secondary mirror in different tilt directions are given in the form of zernike polynomial coefficients, and the influence of the field of view on the sensitivity is expressed in the mathematical model. The desensitization optimization function and desensitization optimization method are proposed. The catadioptric optical system with a focal length of 350 mm is used for desensitization optimization. The results show that the desensitization function proposed in this paper is linearly related to the decrease of sensitivity within a certain range, and the standard deviation of the system after desensitization is 0.020, which is 59% of the system without desensitization. Compared with the traditional method, the method in this paper widens the range of angle reduction sensitivity and has a better desensitization effect. The research results show that the optimization method for low tilt sensitivity of the secondary mirror based on the Nodal aberration theory proposed in this paper reduces the tilt sensitivity of the secondary mirror, revealing that the reduction of the sensitivity depends on the reduction of the aberration coefficient related to the misalignment in the field of view, which is critical for the development of an optical system for aerial mapping cameras that combines imaging and image motion compensation

Conceptual Design and Image Motion Compensation Rate Analysis of Two-Axis Fast Steering Mirror for Dynamic Scan and Stare Imaging System

In order to enable the aerial photoelectric equipment to realize wide-area reconnaissance and target surveillance at the same time, a dual-band dynamic scan and stare imaging system is proposed in this paper. The imaging system performs scanning and pointing through a two-axis gimbal, compensating the image motion caused by the aircraft and gimbal angular velocity and the aircraft liner velocity using two two-axis fast steering mirrors (FSMs). The composition and working principle of the dynamic scan and stare imaging system, the detailed scheme of the two-axis FSM and the image motion compensation (IMC) algorithm are introduced. Both the structure and the mirror of the FSM adopt aluminum alloys, and the flexible support structure is designed based on four cross-axis flexural hinges. The Root-Mean-Square (RMS) error of the mirror reaches 15.8 nm and the total weight of the FSM assembly is 510 g. The IMC rate equations of the two-axis FSM are established based on the coordinate transformation method. The effectiveness of the FSM and IMC algorithm is verified by the dynamic imaging test in the laboratory and flight test

Achromatic and Athermal Design of Aerial Catadioptric Optical Systems by Efficient Optimization of Materials

The remote sensing imaging requirements of aerial cameras require their optical system to have wide temperature adaptability. Based on the optical passive athermal technology, the expression of thermal power offset of a single lens in the catadioptric optical system is first derived, and then a mathematical model for efficient optimization of materials is established; finally, the mechanical material combination (mirror and housing material) is optimized according to the comprehensive weight of offset with temperature change and the position change of the equivalent single lens, and achieve optimization of the lens material on an athermal map. In order to verify the effectiveness of the method, an example of a catadioptric aerial optical system with a focal length of 350 mm is designed. The results show that in the temperature range of −40 °C to 60 °C, the diffraction-limited MTF of the designed optical system is 0.59 (at 68 lp/mm), the MTF of each field of view is greater than 0.39, and the thermal defocus is less than 0.004 mm, which is within one time of the focal depth, indicating that the imaging quality of the optical system basically does not change with temperature, meeting the stringent application requirements of the aerial camera

Assessing the Underwater Acoustics of the World's Largest Vibration Hammer (OCTA-KONG) and Its Potential Effects on the Indo-Pacific Humpbacked Dolphin (Sousa chinensis)

Anthropogenic noise in aquatic environments is a worldwide concern due to its potential adverse effects on the environment and aquatic life. The Hongkong-Zhuhai-Macao Bridge is currently under construction in the Pearl River Estuary, a hot spot for the Indo-Pacific humpbacked dolphin (Sousa chinensis) in China. The OCTA-KONG, the world's largest vibration hammer, is being used during this construction project to drive or extract steel shell piles 22 m in diameter. This activity poses a substantial threat to marine mammals, and an environmental assessment is critically needed. The underwater acoustic properties of the OCTA-KONG were analyzed, and the potential impacts of the underwater acoustic energy on Sousa, including auditory masking and physiological impacts, were assessed. The fundamental frequency of the OCTA-KONG vibration ranged from 15 Hz to 16 Hz, and the noise increments were below 20 kHz, with a dominant frequency and energy below 10 kHz. The resulting sounds are most likely detectable by Sousa over distances of up to 3.5 km from the source. Although Sousa clicks do not appear to be adversely affected, Sousa whistles are susceptible to auditory masking, which may negatively impact this species' social life. Therefore, a safety zone with a radius of 500 m is proposed. Although the zero-to-peak source level (SL) of the OCTA-KONG was lower than the physiological damage level, the maximum root-mean-square SL exceeded the cetacean safety exposure level on several occasions. Moreover, the majority of the unweighted cumulative source sound exposure levels (SSELs) and the cetacean auditory weighted cumulative SSELs exceeded the acoustic threshold levels for the onset of temporary threshold shift, a type of potentially recoverable auditory damage resulting from prolonged sound exposure. These findings may aid in the identification and design of appropriate mitigation methods, such as the use of air bubble curtains, "soft start" and "power down" techniques

Map of the OCTA-KONG vibration monitoring area.

<p>HZMB: Hongkong-Zhuhai-Macao Bridge; PRECWDNNR: The Pearl River Estuary Chinese White Dolphin National Nature Reserve. The eastern boundary of the PRECWDNNR is also the boundary of the Zhuhai and Hongkong Special Administrative Regions. An exclusion zone of 200 m radius was established along the bridge.</p

OCTA-KONG vibration operation.

<p>During vibration, the pile and hammer are rigidly connected (A). The OCTA-KONG was a tandem combination of 8× APE 600 (B), with each APE600 composed of a suppressor housing, a vibrator gearbox and a clamping attachment (C).</p

<i>SL_zp</i>, <i>SL_rms</i> and <i>SSEL_ws</i> of the OCTA-KONG pile driving and pile extraction and the audible range.

<p><i>SSEL_ss</i> was identical to <i>SL_rms</i>. The average levels of the OCTA-KONG and ambientnoise are provided. Numbers in parentheses indicate the range. Sensation level was derived by dividing the vibration sound by the ambient noise level. SLs and SSELs are re 1 µPa and 1 µPa²s, respectively. Subscript 'a' denotes sound recorded by the BS recording system, 'b' denotes sound recorded by the SM2M recording system. * denotes results that exceeded the proposed cetacean safety exposure level of 180 dB (<i>SPL_rms</i>).</p><p><i>SL_zp</i>, <i>SL_rms</i> and <i>SSEL_ws</i> of the OCTA-KONG pile driving and pile extraction and the audible range.</p