China Maritime Report No. 3: China’s Distant-Ocean Survey Activities: Implications for U.S. National Security

Today, the People’s Republic of China (PRC) is investing in marine scientific research on a massive scale. This investment supports an oceanographic research agenda that is increasingly global in scope. One key indicator of this trend is the expanding operations of China’s oceanographic research fleet. On any given day, 5-10 Chinese “scientific research vessels” (科学考查船) may be found operating beyond Chinese jurisdictional waters, in strategically-important areas of the Indo-Pacific. Overshadowed by the dramatic growth in China’s naval footprint, their presence largely goes unnoticed. Yet the activities of these ships and the scientists and engineers they embark have major implications for U.S. national security. This report explores some of these implications. It seeks to answer basic questions about the out-of-area—or “distant-ocean” (远洋)—operations of China’s oceanographic research fleet. Who is organizing and conducting these operations? Where are they taking place? What do they entail? What are the national drivers animating investment in these activities?https://digital-commons.usnwc.edu/cmsi-maritime-reports/1002/thumbnail.jp

China\u27s Evolving Surface Fleet

The missile fast-attack craft and amphibious fleets of the People\u27s Liberation Army (PLA) Navy (PLAN) have undergone significant modernization over the past fifteen years. The capabilities of both categories of vessels have improved even if their actual numbers have not increased dramatically. Examined from the perspective of PLA doctrine and training, the missions of these forces represent the PLAN\u27s past, present, and future.https://digital-commons.usnwc.edu/cmsi-red-books/1013/thumbnail.jp

Beyond the Wall: Chinese Far Seas Operation

This volume is the product of a groundbreaking dialogue on sea-lane security held between People\u27s Liberation Army (PLA) Navy and U.S. Navy scholars at the Naval War College in August 2013, with additional material from a related conference, China\u27s Far Seas Operations, hosted by the China Maritime Studies Institute in May 2012. At that time the political climate in China was uncertain, in the shadow of the Bo Xilai crisis and of the impending transition of power between the Hu and Xi regimes; accordingly the PLA Navy, though invited to participate in the Far Seas conference, ultimately declined to do so. This was not entirely surprising. Attempts by various agencies of the U.S. Navy up to that time to engage in discussions to advance maritime cooperation between China and the United States had been met with lukewarm responses at best. But at a maritime security dialogue in Dalian in September 2012 Senior Capt. Zhang Junshe of the PLA Navy Research Institute, a key contributor to this volume and to the success of the academic cooperation between our two institutes, approached Peter Dutton to tell him that everything had changed.https://digital-commons.usnwc.edu/cmsi-red-books/1012/thumbnail.jp

Types and correlates of school non-attendance in students with autism spectrum disorders

School non-attendance in autism spectrum disorders (ASD) has received very little attention to date. The study aimed to provide a comprehensive description of school non-attendance in students with ASD. Through an online survey, parents of 486 children (mean age 11 years) reported on school attendance over one month, and reasons for instances of non-attendance. On average, students missed five days of school of a possible 23 days. Persistent non-attendance (absent on 10%+ of available sessions) occurred among 43% of students. School non-attendance was associated with child older age, not living in a two-parent household, parental unemployment and, especially, attending a mainstream school. School refusal accounted for 43% of non-attendance. School exclusion and school withdrawal each accounted for 9% of absences. Truancy was almost non-existent. Non-problematic absenteeism (mostly related to medical appointments and illness) accounted for 32% of absences. Non-problematic absenteeism was more likely among those with intellectual disability, school refusal was more likely among older students, and school exclusion was more likely among students from single-parent, unemployed, and well educated households. Findings suggest school non-attendance in ASD is a significant issue, and that it is important to capture detail about attendance patterns and reasons for school non-attendance

Impact of active and passive social facilitation on self paced endurance and sprint exercise: encouragement augments performance and motivation to exercise

Objective The positive effect of an audience on performance is anecdotally well known, but the impact of such social facilitation to both performance and the motivation to exercise have not been thoroughly explored. The aim of this study was therefore to investigate verbal encouragement as a means to promote positive behavioural adherence to exercise and augmented performance. Methods Twelve untrained but active individuals (seven female), age 24±3 years participated in this study. Exercise conditions with external verbal encouragement (EVE) and without external verbal encouragement (WEVE) were compared in both endurance (20 min) and sprint (2 × 30 s Wingate) cycling tasks in a randomised crossover design. Results were analysed by separate 2 (EVE/WEVE) × 2 (sprint/endurance) within-subjects analyses of variance for each dependent variable. Statistical significance was set at p≤0.05. Results EVE resulted in a significant increase, F (1,11)=15.37, p=0.002, η p 2=0.58 in the average power generated by participants in each exercise bout on the cycle ergometer. EVE also had a significant effect on reported motivation to exercise the next day, F (1,11)=5.5, p=0.04, η p 2 =0.33, which did not differ between type of exercise. Conclusion External encouragement in both sprint and endurance activities resulted in large improvements in performance and motivation to continue an exercise regimen the next day, which has important implications for health, adherence and maximising physical performance using a practical intervention

Interaction of laser generated ultrasonic waves with wedge-shaped samples

Wedge-shaped samples can be used as a model of acoustic interactions with samples ranging from ocean wedges, to angled defects such as rolling contact fatigue, to thickness measurements of samples with non-parallel faces. We present work on laser generated ultrasonic waves on metal samples; one can measure the dominant Rayleigh-wave mode, but longitudinal and shear waves are also generated. We present calculations, models, and measurements giving the dependence of the arrival times and amplitudes of these modes on the wedge apex angle and the separation of generation and detection points, and hence give a measure of the wedge characteristics

China Near Seas Combat Capabilities

The capstone U.S. Defense Department study on the future operational environment declares, China\u27s rise represents the most significant single event on the international horizon since the collapse of the Cold War. Understanding and assessing changes in China\u27s traditionally defensive naval strategy, doctrine, and force structure are of obvious importance to the U.S. Navy (USN) and other Pacific navies concerned with the possible security implications of that rise. This chapter examines the development of the Chinese navy\u27s Houbei (Type 022) fast-attack-craft force and its roles and missions in China\u27s near seas and discusses implications for the U.S. Navy and other navies in the region.https://digital-commons.usnwc.edu/cmsi-red-books/1010/thumbnail.jp

CGM properties in VELA and NIHAO simulations; the OVI ionization mechanism: dependence on redshift, halo mass and radius

We study the components of cool and warm/hot gas in the circumgalactic medium (CGM) of simulated galaxies and address the relative production of OVI by photoionization versus collisional ionization, as a function of halo mass, redshift, and distance from the galaxy halo center. This is done utilizing two different suites of zoom-in hydro-cosmological simulations, VELA (6 halos; $z>1$) and NIHAO (18 halos; to $z=0$), which provide a broad theoretical basis because they use different codes and physical recipes for star formation and feedback. In all halos studied in this work, we find that collisional ionization by thermal electrons dominates at high redshift, while photoionization of cool or warm gas by the metagalactic radiation takes over near $z\sim2$. In halos of $\sim 10^{12}M_{\odot}$ and above, collisions become important again at $z<0.5$, while photoionization remains significant down to $z=0$ for less massive halos. In halos with $M_{\textrm v}>3\times10^{11}~M_{\odot}$, at $z\sim 0$ most of the photoionized OVI is in a warm, not cool, gas phase ($T\lesssim 3\times 10^5$~K). We also find that collisions are dominant in the central regions of halos, while photoionization is more significant at the outskirts, around $R_{\textrm v}$, even in massive halos. This too may be explained by the presence of warm gas or, in lower mass halos, by cool gas inflows