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431.
What follows is an attempt to examine new forms of contemporary individual and local collective identity construction. More and more people are constructing their own identities on the basis of active consumption of industrial and symbolic products offered to them by the global electronic and televisual media. This trend is in contrast to the traditional forms of collective identity education which has been carried out on the basis of citizenship of the nation state. The purpose of this paper is to examine the possibility or predicament of local collective identity enculturation within this newly established context global media consumption cultural context.  相似文献   
432.
The economic value of public libraries for local residents in Korea was measured. An economic-value measurement model that enables the estimation of diverse types of public library services was designed, using a conditional-value measurement method. Benefits were taken as the value of the main services provided by public libraries, such as accessibility to informational materials, facilities, and programs. Costs included the total amount of expenses at libraries such as personnel expenses, materials purchasing expenses, and other operational costs. Data were collected from 1220 users from 22 public libraries in the province of Seoul/Gyeonggi-do and the other seven Korean provinces. The return on investment (ROI) was calculated to be 3.66.  相似文献   
433.
A series of ternary organic photovoltaics (OPVs) are fabricated with one wide bandgap polymer D18-Cl as donor, and well compatible Y6 and Y6-1O as acceptor. The open-circuit-voltage (VOC) of ternary OPVs is monotonously increased along with the incorporation of Y6-1O, indicating that the alloy state should be formed between Y6 and Y6-1O due to their excellent compatibility. The energy loss can be minimized by incorporating Y6-1O, leading to the VOC improvement of ternary OPVs. By finely adjusting the Y6-1O content, a power conversion efficiency of 17.91% is achieved in the optimal ternary OPVs with 30 wt% Y6-1O in acceptors, resulting from synchronously improved short-circuit-current density (JSC) of 25.87 mA cm−2, fill factor (FF) of 76.92% and VOC of 0.900 V in comparison with those of D18-Cl : Y6 binary OPVs. The JSC and FF improvement of ternary OPVs should be ascribed to comprehensively optimal photon harvesting, exciton dissociation and charge transport in ternary active layers. The more efficient charge separation and transport process in ternary active layers can be confirmed by the magneto-photocurrent and impedance spectroscopy experimental results, respectively. This work provides new insight into constructing highly efficient ternary OPVs with well compatible Y6 and its derivative as acceptor.  相似文献   
434.
A class of discrete-time nonlinear system and measurement equations having incrementally conic nonlinearities and finite energy disturbances is considered. A linear matrix inequality-based design approach is presented, which guarantees the satisfaction of a variety of performance criteria ranging from simple estimation error boundedness to dissipativity. Some simulation examples are included to illustrate and provide support to the proposed design methodology.  相似文献   
435.
With an increase in the number of online tests, the number of interruptions during testing due to unexpected technical issues seems to be on the rise. For example, interruptions occurred during several recent state tests. When interruptions occur, it is important to determine the extent of their impact on the examinees' scores. Researchers such as Hill and Sinharay et al. examined the impact of interruptions at an aggregate level. However, there is a lack of research on the assessment of impact of interruptions at an individual level. We attempt to fill that void. We suggest four methodological approaches, primarily based on statistical hypothesis testing, linear regression, and item response theory, which can provide evidence on the individual‐level impact of interruptions. We perform a realistic simulation study to compare the Type I error rate and power of the suggested approaches. We then apply the approaches to data from the 2013 Indiana Statewide Testing for Educational Progress‐Plus (ISTEP+) test that experienced interruptions.  相似文献   
436.
Limited research has examined the skills of children with a reading disability (RD) and children with RD and a mathematics disability (MD). Even less research has examined the phonological awareness (PA) and rapid automatized naming (RAN) skills in these two groups of children and how these skills relate to reading and math achievement. Additionally, various classification criteria are frequently implemented to classify children with MD. The purpose of this study, therefore, was to examine the PA and RAN skills in children who met different criteria for RD only and children with RD who are at risk for mathematics difficulties (MDR). Participants were 114 second‐ or third‐grade students with RD from public elementary schools in three large metropolitan areas. Students were classified as at risk for mathematics difficulties utilizing a 25th‐percentile cutoff and a 15th‐percentile cutoff as assessed by the KeyMath‐Revised Test ( Connolly, 1988 ). A series of PA and RAN measures were administered along with a range of reading and mathematics measures. Hierarchical regression analyses indicated that children with RD only evidenced a different pattern of results compared to children with RD + MDR. Additionally, using a more stringent criterion to classify children at risk for mathematics difficulties resulted in a differential pattern of results when compared to a less stringent classification criterion.  相似文献   
437.
In this paper, we study the variation of the thickness of patterned microchannel features in photoresist (PR) by two-step photolithography. The final PR thickness is determined by the thickness and width of the predefined PR pattern in the first-step lithography and the thickness of the spin-coated PR film in the second-step lithography. Thickness variation is demonstrated to be an important consideration within the critical pattern width that the capillary pressure is still dominant for forming the PR film thickness. With this mechanism of two-step photolithography, we demonstrate its ability to form multilevel channel features and its use to fabricate a cross-flow filter with two different pore sizes as a microfluidic application.  相似文献   
438.
The random walk of spherical living cells on a silicon dioxide glassy substrate was studied experimentally and numerically. This random walk trajectory exhibited erratic dancing, which seemingly obeyed anomalous diffusion (i.e., Lévy-like walk) rather than normal diffusion. Moreover, the angular distribution (−π to π) of the cells'' trajectory followed a “U-shaped pattern” in comparison to the uniform distribution seen in the movements of negatively charged polystyrene microspheres. These effects could be attributable to the homeostasis-driven structural resilient character of cells and physical interactions derived from temporarily retained nonspecific binding due to weak forces between the cells and substrates. Our results provide new insights into the stochastic behavior of mesoscopic biological particles with respect to structural properties and physical interactions.  相似文献   
439.
Combining the conceptual approach of racial formation and racial projects with the Foucauldian concept of governmentality, Jeong‐eun Rhee theorizes the “neoliberal racial project” (NRP) and examines contemporary meanings and operations of race and racism in relation to neoliberalism. She analyzes Amy Chua's popular parenting memoir, Battle Hymn of the Tiger Mother, as a specific case of the NRP, and demonstrates how in this text race is pressed to work in new — neoliberal — ways, re/generating different kinds of categories and meanings, yet also continuously drawing upon old categories and meanings, to effect and rationalize social arrangements of power and exploitation, violence and expropriation. What is noteworthy is the way in which racial neoliberalism builds silently on the structural conditions of racism while disabling the very categories of their recognizability. Consequently, Rhee argues for new, historically bounded theories that can articulate how the meanings, categories, and concepts of races are constantly being reconfigured.  相似文献   
440.
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