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941.
942.
Instagram and other photo-based social networking sites have emerged as a popular medium. Previous studies mainly focused on social media texts, but the current study deals with the relationships between the characteristics of Instagram users and the features of their photos. The Big Five personality traits and gender were employed as the variables for user characteristics. Content category, the number of faces, the emotions on the faces, and the pixel derived features were employed as the variables for photo characteristics. An online survey of 179 university students was conducted to measure user characteristics, and 25,394 photos in total were downloaded and analyzed from the respondents’ Instagram accounts. Results suggested that content category is associated with extraversion and gender of users. The number of faces is associated with extraversion, agreeableness, and openness of users. Extraversion, agreeableness, and openness of users were partly associated with emotions expressed on the faces in their photos. Correlations were observed among some pixel features and extraversion, agreeableness, conscientiousness, and gender of users. It was also observed that the Big Five personality traits, except for gender, can be predicted by above variables. Implications and limitations are discussed and suggestions for future research are suggested. 相似文献
943.
Consumers evaluate products through online reviews, in addition to sharing their product experiences. Online reviews affect product marketing, and companies use online reviews to investigate consumer attitudes and perceptions of their products. However, when analyzing a review, it is often the case that specific contexts are not taken into consideration and meaningful information is not obtained from the analysis results. This study suggests a methodology for analyzing reviews in the context of comparing two competing products. In addition, by analyzing the discriminative attributes of competing products, we were able to derive more specific information than an overall product analysis. Analyzing the discriminative attributes in the context of comparing competing products provides clarity on analyzing the strengths and weaknesses of competitive products and provides realistic information that can help the company's management activities. Considering this purpose, this study collected a review of the BB Cream product line in the cosmetics field. The analysis was sequentially carried out in three stages. First, we extracted words that represent discriminative attributes by analyzing the percentage difference of words. Second, different attribute words were classified according to the meaning used in the review by using latent semantic analysis. Finally, the polarity of discriminative attribute words was analyzed using Labeled-LDA. This analysis method can be used as a market research method as it can extract more information than a traditional survey or interview method, and can save cost and time through the automation of the program. 相似文献
944.
This article reports survey findings related to the current status and future trends of blended learning in workplace learning
settings from diverse cultures. This particular survey was conducted of 674 training and human resource development professionals
from five different countries, mostly from the Asia-Pacific region (i.e., China, South Korea, Taiwan, United States, and the
United Kingdom). The results show that blended learning will become a popular delivery method in the future of workplace learning
not only in Western countries but also in Asian countries. Still, the respondents indicated that there were several barriers
to blended learning; one of the most noticeable issues was their lack of understanding of blended learning. There is a pressing
need, therefore, to provide practitioners with guidance on how to implement blended learning in their organizations. Additionally,
among the countries surveyed, the results of the present study revealed that there were significant differences in the current
level of adoption of blended learning, the respondents’ attitudes toward and perceptions of blended learning, and the content
areas taught by blended learning. Respondents’ predictions related to emerging instructional strategies, technologies, and
evaluation techniques for blended learning are also reported. 相似文献
945.
Min Kyu Kim 《TechTrends》2009,53(6):12
ect Cornerstone
ECT Internship: Experiencing Privilege, Opportunity, and the Spirit of Giving 相似文献946.
Paul H. Kim 《Educational technology research and development : ETR & D》2009,57(3):415-435
This paper discusses an action research study focused on developing a mobile learning model of literacy development for underserved
migrant indigenous children in Latin America. The research study incorporated a cyclical action model with four distinctive
stages (Strategize, Apply, Evaluate, and Reflect) designed to guide constituencies involved in the study to design, test,
and enhance a mobile learning model. The findings, to date, reveal some of the contextual phenomena that create both challenges
and opportunities for a mobile learning model. From this, design strategies are evolving focused on sustained literacy exposure
for extremely marginalized (economically, educationally, geographically, and technologically) migrant indigenous children
who have no consistent access to a formal education system. 相似文献
947.
Kibum Kim Scott A. Turner Manuel A. Pérez-Quiñones 《Education and Information Technologies》2009,14(3):255-283
Note taking is the core activity for students in a classroom. There has been a large amount of research conducted, both from
industry and from academia, into facilitating the note-taking process. There is evidence that shows that note taking can be
beneficial for the students’ educational growth. There are also many available systems for taking notes electronically (e.g.
Tablet PCs, PDAs). However, what has not been given as much attention is how these electronic devices affect (or support)
the note taking task. In this paper, we study university students’ current note taking behavior and the changes caused by
the use of electronic systems for this activity. The goal of our work is to identify issues that should be considered when
evaluating electronic note taking systems and to formulate requirements for future electronic note-taking systems. Our findings
show that while the technological support for writing with pens on electronic surfaces is quite advanced, the task of note
taking in the classroom is not well supported. We identify the limitations of typical note taking systems and discuss the
implications for the design of future note taking systems. Our work consisted of three parts: a survey of current note-taking
practices, an observational study in a classroom environment, and a semester long case study of students using electronic
note-taking devices. All of these activities took place at a large 4-year university. We found that the people reacted to
note-taking devices very differently and that their current practices were not always well supported. The users all wanted
to input information as fast as possible, in the manner they wanted but they were not always able to achieve that. Hardware
limitations (i.e. screen size, responsiveness) added to this issue. We also found that the features that are well supported
in an electronic medium (i.e. modification, reorganizing, multiple pen colors/styles, handwriting recognition, sharing) were
not commonly used or wanted. 相似文献
948.
This study presents a method for density-based separation of monodisperse encapsulated cells using a standing surface acoustic wave (SSAW) in a microchannel. Even though monodisperse polymer beads can be generated by the state-of-the-art technology in microfluidics, the quantity of encapsulated cells cannot be controlled precisely. In the present study, mono-disperse alginate beads in a laminar flow can be separated based on their density using acoustophoresis. A mixture of beads of equal sizes but dissimilar densities was hydrodynamically focused at the entrance and then actively driven toward the sidewalls by a SSAW. The lateral displacement of a bead is proportional to the density of the bead, i.e., the number of encapsulated cells in an alginate bead. Under optimized conditions, the recovery rate of a target bead group (large-cell-quantity alginate beads) reached up to 97% at a rate of 2300 beads per minute. A cell viability test also confirmed that the encapsulated cells were hardly damaged by the acoustic force. Moreover, cell-encapsulating beads that were cultured for 1 day were separated in a similar manner. In conclusion, this study demonstrated that a SSAW can successfully separate monodisperse particles by their density. With the present technique for separating cell-encapsulating beads, the current cell engineering technology can be significantly advanced. 相似文献
949.
Francesco Piraino ?eila Selimovi? Marco Adamo Alessandro Pero Sam Manoucheri Sang Bok Kim Danilo Demarchi Ali Khademhosseini 《Biomicrofluidics》2012,6(4)
The application of microfluidic technologies to stem cell research is of great interest to biologists and bioengineers. This is chiefly due to the intricate ability to control the cellular environment, the reduction of reagent volume, experimentation time and cost, and the high-throughput screening capabilities of microscale devices. Despite this importance, a simple-to-use microfluidic platform for studying the effects of growth factors on stem cell differentiation has not yet emerged. With this consideration, we have designed and characterized a microfluidic device that is easy to fabricate and operate, yet contains several functional elements. Our device is a simple polyester-based microfluidic chip capable of simultaneously screening multiple independent stem cell culture conditions. Generated by laser ablation and stacking of multiple layers of polyester film, this device integrates a 10 × 10 microwell array for cell culture with a continuous perfusion system and a non-linear concentration gradient generator. We performed numerical calculations to predict the gradient formation and calculate the shear stress acting on the cells inside the device. The device operation was validated by culturing murine embryonic stem cells inside the microwells for 5 days. Furthermore, we showed the ability to maintain the pluripotency of stem cell aggregates in response to concentrations of leukemia inhibitory factor ranging from 0 to ∼1000 U/ml. Given its simplicity, fast manufacturing method, scalability, and the cell-compatible nature of the device, it may be a useful platform for long-term stem cell culture and studies. 相似文献
950.
Kyung Kyu Kim Narayan S. Umanath Joo Young Kim Fred Ahrens Beomsoo Kim 《International Journal of Information Management》2012
Existing literature on knowledge exchange in inter-organizational relationships (e.g., a supply channel) reveals two opposing forces at work: (1) collaborative behavior and (2) opportunistic behavior. A concurrent assessment of the opposing perspectives and the contingencies under which each is relevant for supply channel performance can add valuable insights about the dynamics of knowledge exchange. We juxtapose the two behavior patterns using social capital theory and transaction cost economics (TCE) respectively as the explicators and employ knowledge complementarity as the contingency to reconcile the opposing behavior patterns. The choice of knowledge complementarity in this role stems from ample theoretical and empirical support in prior literature about the criticality of this factor in inter-firm knowledge exchange. 相似文献