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1.
ABSTRACTThis study focuses on the decisive role played by the digital design environment in the cognitive design process and design thinking. To analyse the cognitive role of digital design tools, we carried out a protocol analysis of conventional design sketching and a 3D sculpture tool. Cognitive evaluation was a differentiating factor when considering the contextual role of the 3D sculpture tool in subsequent evaluations, non-sequential evaluations for conversion, and passive approaches within the design process. Cognitive evaluation played the following roles: validation, extension, navigation, exploration, and confirmation. The navigation, exploration, and extension roles played by non-sequential evaluation were mainly related to inductive design thinking. Finally, the types of cognitive evaluation and their roles when using the 3D sculpture tool were different, according to the design thinking type. This study explored the multidimensional roles of cognitive evaluation using a 3D sculpture tool and its relationship with design thinking types. 相似文献
2.
Mesoporous Germanium Anode Materials for Lithium‐Ion Battery with Exceptional Cycling Stability in Wide Temperature Range 下载免费PDF全文
Sinho Choi Yoon‐Gyo Cho Jieun Kim Nam‐Soon Choi Hyun‐Kon Song Guoxiu Wang Soojin Park 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(13)
Porous structured materials have unique architectures and are promising for lithium‐ion batteries to enhance performances. In particular, mesoporous materials have many advantages including a high surface area and large void spaces which can increase reactivity and accessibility of lithium ions. This study reports a synthesis of newly developed mesoporous germanium (Ge) particles prepared by a zincothermic reduction at a mild temperature for high performance lithium‐ion batteries which can operate in a wide temperature range. The optimized Ge battery anodes with the mesoporous structure exhibit outstanding electrochemical properties in a wide temperature ranging from ?20 to 60 °C. Ge anodes exhibit a stable cycling retention at various temperatures (capacity retention of 99% after 100 cycles at 25 °C, 84% after 300 cycles at 60 °C, and 50% after 50 cycles at ?20 °C). Furthermore, full cells consisting of the mesoporous Ge anode and an LiFePO4 cathode show an excellent cyclability at ?20 and 25 °C. Mesoporous Ge materials synthesized by the zincothermic reduction can be potentially applied as high performance anode materials for practical lithium‐ion batteries. 相似文献
3.
Enhancing Interfacial Bonding between Anisotropically Oriented Grains Using a Glue‐Nanofiller for Advanced Li‐Ion Battery Cathode 下载免费PDF全文
4.
Ab initio predictions of secondary structures in proteins have to combine local predictions, based on short fragments of the
protein sequence, with consistency restrictions, as not all locally plausible predictions may be simultaneously true.
We use the fact that secondary structures are patterns of hydrogen bonds and that a single residue can participate in hydrogen
bonds of at most one secondary structure. Consistency of fixed-sized pieces of secondary structures is the easiest to approximate
and we formalize it as 1-2 matching problem. Consistency of entire secondary structures is a version of set packing. We also
investigate how to form a simple problem if we add the requirement that the secondary structure and the loops that connect
them fit together in a metric space.
Every problem that we investigated is MAX-SNP hard and it has a constant factor approximation. Computational experience suggests
that in biological instances, we can find nearly optimal solutions using heuristics. 相似文献
5.
Bong Jin Kang Jinhyoung Park Jieun Kim Hyung Ham Kim Changyang Lee Jae Youn Hwang Ching-Ling Lien K. Kirk Shung 《Journal of the Royal Society Interface》2015,12(103)
Adult zebrafish is a well-known small animal model for studying heart regeneration. Although the regeneration of scars made by resecting the ventricular apex has been visualized with histological methods, there is no adequate imaging tool for tracking the functional recovery of the damaged heart. For this reason, high-frequency Doppler echocardiography using dual mode pulsed wave Doppler, which provides both tissue Doppler (TD) and Doppler flow in a same cardiac cycle, is developed with a 30 MHz high-frequency array ultrasound imaging system. Phantom studies show that the Doppler flow mode of the dual mode is capable of measuring the flow velocity from 0.1 to 15 cm s−1 with high accuracy (p-value = 0.974 > 0.05). In the in vivo study of zebrafish, both TD and Doppler flow signals were simultaneously obtained from the zebrafish heart for the first time, and the synchronized valve motions with the blood flow signals were identified. In the longitudinal study on the zebrafish heart regeneration, the parameters for diagnosing the diastolic dysfunction, for example, E/Em < 10, E/A < 0.14 for wild-type zebrafish, were measured, and the type of diastolic dysfunction caused by the amputation was found to be similar to the restrictive filling. The diastolic function was fully recovered within four weeks post-amputation. 相似文献
6.
Magnetic Resonance Materials in Physics, Biology and Medicine - This study aims to compare an electrocardiogram (ECG)-gated four-dimensional (4D) phase-contrast (PC) magnetic resonance imaging... 相似文献
7.
Jieun Kim Seung Yeon Oh Jae Yeong Park Younghun Kim 《Korean Journal of Chemical Engineering》2016,33(1):344-349
A facile and rapid method for the synthesis of porous gold (PAu) electrodes on cellulose-filters is proposed. Morphology and active surface area of the electrode greatly influence the electrochemical properties of sensor. Compared to smooth electrode and glassy carbon, PAu and Pt/PAu electrode showed high roughness due to porous structure, which is helpful in electrochemical sensing of target molecules. The electrochemical sensing performance of Pt/PAu electrode was evaluated to detect hydrogen peroxide, glucose, and perchloric acid. The amperometric results with various concentrations of target molecules showed potential applications of Pt/PAu electrode in sensitive and effective chemical sensors. 相似文献
8.
An increasingly widespread interest in developing fully adaptable e-learning systems (e.g., intelligent tutoring systems) has led to the development of a wide range of adaptive processes and techniques. In particular, advances in these systems are based on optimization for each user's learning style and characteristics, to enable a personalized learning experience. Current techniques are aimed at using a learner's personality traits and its effect on learning preferences to improve both the initial learning experience and the information retained (e.g., top-down or bottom-up learning organization). This study empirically tested the relationship between a learner's personality traits, analyzed the effects of these traits on learning preferences, and suggested design guidelines for adaptive learning systems. Two controlled experiments were carried out in a computer-based learning session. Our first experiment showed a significant difference in the learning performance of participants who were identified as introverts vs. those who were identified as being extroverts, according to the MBTI scale. As the distinction between extroverted personality types vs. introverted personality types showed the strongest correlation in terms of different learning styles, we used this criteria in our second experiment to determine whether design guidelines for appropriate content organization could reinforce the aforementioned correlation between personality type and learning experience. 相似文献
9.
Jieun Kim Jae Sung Lee Jong Bum Lee 《International journal of molecular sciences》2015,16(4):7738-7747
Fluorescent labeling is widely used to investigate the structural stability and changes to DNA nano- and microstructures. Despite this, the conventional method for observing DNA structures has several limitations in terms of cost-efficiency. This paper introduces a DNA spherical particle stained with DNA intercalating dyes (SYBR Green and SYTOX Orange) as tracers and reports the interaction between multiple dyes. The interference between the dyes was analyzed in terms of Förster resonance energy transfer (FRET) and competition. The changes in the fluorescence intensity by FRET were uniform, regardless of the sequence. The competition effect could occur when several dyes were added simultaneously. These properties are expected to help in the design of multicolor tracers in bioimaging and environmental applications. 相似文献
10.
Lee H Yoon H Ji Y Kim H Park H Lee J Shin H Holzapfel W 《International journal of food microbiology》2011,145(1):155-161
The objective of this study was to evaluate the functional properties of lactic acid bacteria (LAB) from kimchi, a traditional Korean fermented vegetable product generally consumed raw as a side-dish with practically every meal.Twelve mild acid producing facultatively heterofermentative Lactobacillus strains were selected for their potential as starter cultures for fermentation of kimchi, and evaluated for their functional properties. Eleven strains were identified as Lactobacillus sakei and one as Lactobacillus plantarum. The strains identified as L. sakei differed in some physiological features; of particular interest was the fact that 9 of these strains produced L(+) lactic acid from glucose in presence of acetate.All strains were able to survive gastrointestinal conditions simulating stomach and duodenum passage. In addition, they showed higher adherence to HT-29 cells than Lactobacillus rhamnosus GG, a commercial probiotic strain used worldwide. These strains also showed antimicrobial activity against a number of food-borne pathogens. Their ability to lower cholesterol was demonstrated by BSH (bile salt hydrolytic) activity, and cholesterol assimilation tests in vitro. The results suggest the probiotic potential of these strains for use in kimchi fermentation. 相似文献