Electro-mechanically controlled assembly of reconfigurable 3D mesostructures and electronic devices based on dielectric elastomer platforms     

Wenbo Pang  Xu Cheng  Haojie Zhao  Xiaogang Guo  Ziyao Ji  Guorui Li  Yiming Liang  Zhaoguo Xue  Honglie Song  Fan Zhang  Zheng Xu  Lei Sang  Wen Huang  Tiefeng Li  Yihui Zhang 《国家科学评论(英文版)》2020,7(2):342

The manufacture of 3D mesostructures is receiving rapidly increasing attention, because of the fundamental significance and practical applications across wide-ranging areas. The recently developed approach of buckling-guided assembly allows deterministic formation of complex 3D mesostructures in a broad set of functional materials, with feature sizes spanning nanoscale to centimeter-scale. Previous studies mostly exploited mechanically controlled assembly platforms using elastomer substrates, which limits the capabilities to achieve on-demand local assembly, and to reshape assembled mesostructures into distinct 3D configurations. This work introduces a set of design concepts and assembly strategies to utilize dielectric elastomer actuators as powerful platforms for the electro-mechanically controlled 3D assembly. Capabilities of sequential, local loading with desired strain distributions allow access to precisely tailored 3D mesostructures that can be reshaped into distinct geometries, as demonstrated by experimental and theoretical studies of ∼30 examples. A reconfigurable inductive–capacitive radio-frequency circuit consisting of morphable 3D capacitors serves as an application example.  相似文献   

Now and forever: portraits of qualitative research in Korea     

Young Chun Kim  Jeasik Cho 《International journal of qualitative studies in education》2013,26(3):355-377

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Becoming Co-Authors: Toward Sharing Authority in Religious Education     

Hyun-Sook Kim 《Religious education (Chicago, Ill.)》2013,108(5):479-491

This article offers an alternative model, the model of shared authority, to the traditional, authoritarian model for authority and obedience for Religious Education. This model moves away from the authoritarian model of a teacher as the authority and the students as obedient listeners in the direction of a shared authority model in which teachers and students participate in learning as partners, in other words, “to become co-authors.”  相似文献   

New Vision and Challenges in Inquiry-Based Curriculum Change in Singapore     

Mijung Kim  Frederick Toralballa Talaue 《International Journal of Science Education》2013,35(2):289-311

A new primary science syllabus with strong inquiry focus has been implemented in Singapore since 2008. In this study, we attempted to understand how teachers experience the emphasis of inquiry-based curriculum under the current educational conditions that is routined and highly teacher fronted. We invited 50 pre-service and 41 in-service teachers to participate in survey questionnaires and narratives, reflective writings, and group discussions related to science inquiry which formed our data corpus. Data analysis in the form of thematic coding was carried out using NVivo8, with over 80% inter-rater coding agreement level. Three key aspects of teachers’ perceptions of science inquiry were revealed: (1) teachers’ responsibilities as facilitators, (2) privileging content knowledge rather than process skills, and (3) pressure of assessment systems in current educational contexts. These understandings bring out conflicts of inquiry teaching between teacher- and student-centredness, content and process, and curriculum and assessment. Based on these teachers’ perceptions and dilemmas of inquiry science teaching, the visions and challenges of inquiry science curriculum change against assessment requirements are discussed.  相似文献   

Kicking modality during erratic-dynamic and static condition effects the muscular co-activation of attacker     

Tae-Whan Kim  Sang-Cheol Lee  Se-Kee Kil  Sung-Chul Kang  Young-Tae Lim 《Journal of sports sciences》2017,35(9):835-841

The purpose of the study was to investigate the effect of different kicking modality, i.e., erratic-dynamic target (EDT) versus static target (ST) on the performance of the roundhouse kick in two groups of taekwondo athletes of different skill level. Three-dimensional analysis and surface electromyography (SEMG) analysis were performed on 12 (Group A: six sub-elite, Group B: six elite) athletes to investigate muscle co-activation pattern under two conditions, i.e., EDT versus ST. In the results, the muscle recruitment ratio of the agonistic muscles was higher for Group A, whereas Group B had higher recruitment ratio for antagonist muscles. Overall, the co-activation index (CI) of hip joints appeared higher in the extensors for Group A, whereas higher CI was observed in flexor muscles for Group B with comparatively higher CI during EDT condition than ST condition. Higher value of CI was observed in flexor muscles of the knee joints among Group A during EDT conditions, in contrast, higher CI in the extensor muscles was observed among Group B during ST conditions. In conclusion, the study confirmed that erratic-dynamic movements of target could change the movement coordination pattern to maintain the joint stability of participants.  相似文献   

Grounded theory analysis of e-government initiatives: Exploring perceptions of government authorities     

Jungwoo Lee  Jinhwa Kim 《Government Information Quarterly》2007

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Managing IT-enabled transformation in the public sector: A case study on e-government in South Korea     

Hyun Jeong Kim  Gary Pan  Shan Ling Pan 《Government Information Quarterly》2007

The implementation of e-government is a burgeoning phenomenon across the globe. It improves and enhances the infrastructures and services provided to the citizens. However, a review of the IS literature reveals that research on the implementation of e-government is rather limited, which could be due to the general misconception of the public sectors as rigid and risk-averse establishments. The shortage of studies on e-government’s implementation presents a knowledge gap that needs to be plugged. This gap is significantly amplified by the increasing number of e-government initiatives being implemented by governments in recent years. This paper describes and analyzes South Korea’s Supreme Court Registry Office, which has implemented e-government. The case study discusses practical implications and suggests future research areas. Findings of the study include the alignment of technology and business processes, integration of resources into core business activities, integrating stakeholders’ trust and commitment, and better understanding of the role of organizational learning, which can enhance the adoption and institutionalization of e-government initiatives.  相似文献   

社会性网络服务的特点及其对企业竞争情报工作的影响   总被引：2，自引：0，他引：2  

秦铁辉  桑晓琦 《图书情报知识》2007,33(6):11-15

当前,互联网已成为企业竞争情报工作的重要阵地,人际网络在整个情报循环中的作用已受到相当程度的重视。本文从当前网络热点社会性网络服务(SNS)入手,分析了基于SNS构建的人际网络特点,对由此引发的企业竞争情报工作的变革进行了探讨,重点分析了社会性网络服务对企业竞争情报收集内容及方式的影响。  相似文献   

Differences between the sexes in the three-dimensional angular rotations of the lumbo-pelvic-hip complex during treadmill running     

Schache AG  Blanch P  Rath D  Wrigley T  Bennell K 《Journal of sports sciences》2003,21(2):105-118

The aims of this experiment were to determine whether there are differences between the sexes in the three-dimensional angular rotations of the lumbo-pelvic-hip complex during running and, if such differences exist, to establish whether factors other than sex can explain the observed differences. A cohort of 44 non-injured runners (22 males, 22 females) who usually ran more than 20 km per week were voluntarily recruited. All trials were conducted on a treadmill at a running speed of 4.0 m x s(-1). Reflective markers were placed over specific anatomical landmarks of the thoraco-lumbar spine, pelvis and femur. Data were captured using a VICON motion analysis system. Females tended to display a greater peak-to-peak oscillation for most of the angular rotations. An offset was the main difference between the male and female group mean waveforms for pelvis anterior-posterior tilt. Forward stepwise regression analysis revealed that sex was the most common variable related to the amplitudes of the angular rotations. Given these results, sport scientists conducting future biomechanical studies using angular data to test hypotheses are advised to be extremely cautious about averaging across male and female participants.  相似文献   

论图书馆管理的人本主义价值取向   总被引：17，自引：0，他引：17  

桑晓东  宋书星 《图书情报工作》2003,46(9):40-44

在科学管理与人本管理比较的基础上,提出图书馆应坚持科学管理与人本管理、科学精神与人文精神相统一;并简要分析现行图书馆规章制度的缺失及其修订完善所应遵循的基本原则。指出,管理体制“软件”现代化是图书馆现代化建设不容忽视的重要内容。  相似文献