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Combinational creativity is a significant element of design in supporting designers to generate creative ideas during the early phases of design. There exists three driven approaches to combinational creativity: problem-, similarity- and inspiration-driven. This study provides further insights into the three combinational creativity driven approaches, exploring which approach could lead to ideas that are more creative in the context of practical product design. The results from a case study reveal that the problem- driven approach could lead to more creative and novel ideas or products compared with the similarity- and inspiration-driven approach. Products originating from the similarity- and inspiration-driven approach are at comparable levels. This study provides better understanding of combinational creativity in practical design. It also delivers benefits to designers in improving creative idea generation, and supports design researchers in exploring future ideation methods and design support tools employing the concept of 'combination'.
Analogy is a core cognition process used to produce inferences as well as new ideas using previous knowledge and experience. Ontology is a formal representation of a set of domain concepts and their relationships. The use of analogy and ontology in design activities to support design creativity have previously been explored. This paper explores an approach to construct ontologies with sufficient richness and coverage to support reasoning over real-world datasets for prompting creative idea generation. This approach has been implemented into a computational tool for assisting designers in generating creative ideas during the early stages of design. The tool, called “the Retriever”, has been developed based on ontology by embracing the aspects of analogical reasoning. A case study has indicated that the tool can be effective and useful for idea generation. The results have indicated that the tool, in its current formulation, can significantly improve the fluency and flexibility of idea generation and the usefulness of ideas, as well as slightly increase the originality of ideas, for the case study concerned.
The basic principle of high-entropy alloys (HEAs) is that high mixing entropies of solid-solution phases enhance the phase stability, which renders us a new strategy on alloy design. The current research of HEAs mostly emphasizes mechanical behavior at room and higher temperatures. Relatively fewer papers are focused on low-temperature behaviors, below room temperature. However, based on the published papers, we can find that the low-temperature properties of HEAs are generally excellent. The great potential for cryogenic applications could be expected on HEAs. In this article, we summarized and discussed the mechanical behaviors and deformation mechanisms, as well as stacking-fault energies, of HEAs at low temperatures. The comparison of low-temperature properties of HEAs and conventional alloys will be provided. Future research directions will be suggested at the end.
Idea generation is significant in design, but coming up with creative ideas is often challenging. This paper presents a computer-based tool, called the Combinator, for assisting designers to produce creative ideas. The tool is developed based on an approach simulating aspects of human cognition in achieving combinational creativity. It can generate combinational prompts in text and image forms through combining unrelated ideas. A case study has been conducted to evaluate the Combinator. The study results indicate that the Combinator, in its current formulation, has assisted the tool users involved in the case study in improving the fluency of idea generation, as well as increasing the originality, usefulness, and flexibility of the ideas generated. The results also indicate that the tool could benefit its users in generating high-novelty and high-quality ideas effectively. The Combinator is considered to be beneficial in expanding the design space, increasing better idea occurrence, improving design space exploration, and enhancing the design success rate.
Whether there are distinct subtypes of schizophrenia is an important issue to advance understanding and treatment of schizophrenia.
To understand and treat individuals with schizophrenia, the aim was to advance understanding of differences between individuals, whether there are discrete subtypes, and how fist-episode patients (FEP) may differ from multiple episode patients (MEP).
These issues were analysed in 687 FEP and 1880 MEP with schizophrenia using the Positive and Negative Syndrome Scale for (PANSS) schizophrenia before and after antipsychotic medication for 6 weeks.
The seven Negative Symptoms were correlated with each other and with P2 (conceptual disorganisation), G13 (disturbance of volition), and G7 (motor retardation). The main difference between individuals was in the cluster of seven negative symptoms, which had a continuous unimodal distribution. Medication decreased the PANSS scores for all the symptoms, which were similar in the FEP and MEP groups.
The negative symptoms are a major source of individual differences, and there are potential implications for treatment.
In 41 patients with schizophrenia, we used neuroanatomical information
derived from structural imaging to identify patients with more severe
illness, characterised by high symptom burden, low processing speed, high
degree of illness persistence and lower social and occupational functional
capacity. Cortical folding, but not thickness or volume, showed a high
discriminatory ability in correctly identifying patients with more severe
In this study, we examine the effect of surface density of disks on chemical evolution of galaxies. We find that, higher surface brightness galaxies on average possess higher gas-phase metallicity compared to lower surface brightness galaxies with the same stellar and gas mass. The surface brightness effect is more significant for low-mass galaxies. Using an analytical model of chemical evolution involving gas outflow and accretion, we find that the surface brightness dependence can be attributed to the strength of inflowing pristine gas. Galaxies with lower surface brightness experience stronger inflow than galaxies with a higher surface brightness of a similar mass.
This paper reports low temperature, digital control, fast synthesis of high-quality boron nitride nanosheets (BNNSs) and their electronic device application. Raman scattering spectroscopy, X-ray diffraction (XRD), Transmission electron microscopy (TEM) are used to characterize the BNNSs. With the synthesized various BNNSs, two prototypic types of deep UV photodetectors have been fabricated, and sensitivity, response and recovery times, as well as repeatability have been characterized. Effects of period and thickness of BNNSs on the properties of prototypic photodetectors are also discussed.
We consider the stability of a long free film of liquid composed of two immiscible layers of differing viscosities, where each layer experiences a van der Waals force between its interfaces. We analyse the different ways in which the system can exhibit interfacial instability when the liquid layers are sufficiently thin. For an excess of surfactant on one gas–liquid interface, the coupling between the layers is relatively weak and the instability is manifested as temporally separated rupture events in each layer. Conversely, in the absence of surfactant, the coupling between the layers is much stronger and the instability is manifested as rupture of both layers simultaneously. These features are consistent with recent experimental observations.
The superstructures of different morphology (superlattices and supercrystals) are obtained by self-organization of lead sulfide quantum dots (QDs) on a substrate. In contrast to the SAXS patterns of isolated QDs in solutions, the X-ray intensity from ordered superstructures is modulated by the interference from the QDs in SLs or SCs leading to occurrence of the intense peaks at small scattering angles. By indexing the peaks in the SAXS patterns it is concluded that QD SLs are close-packed QD ensembles with the lattice parameter close to the dot diameter and QD SCs have primitive orthorhombic crystal lattice. Absorption and photoluminescence bands of superstructures are also analyzed.
The process of laser-induced brazing constitutes a potential option for connecting several ceramic components (n- and p-type ceramic bars and ceramic substrate) of a thermoelectric generator (TEG) unit. For the construction of the TEGs, TiOx and BxC were used as thermoelectric bars and AlN was used as substrate material. The required process time for joining is well below that of conventional furnace brazing processes and, furthermore, establishes the possibility of using a uniform filler system for all contacting points within the thermoelectric unit. In the work reported here, the application-specific optimization of the laser-joining process is presented as well as the adapted design of the thermoelectric modules. The properties of the produced bonding were characterized by using fatigue strength and microstructural investigations. Furthermore, the operational reliability of the modules was verified.
Traditionally tissue engineering entails the seeding and culturing of differentiated somatic cells onto biodegradable scaffolds, with subsequent implantation of the cell–scaffold constructs into the defective or damaged sites to regenerate tissues . In this approach, the scaffold acts as a three-dimensional (3D) framework to provide physical support and accommodate cell growth and deposition of extracellular matrices, and its biodegradability allows the scaffold material to be resorbed in pace with new tissue formation. Despite some encouraging successes in clinical trials [2, 3], two key limitations with this approach include the limited source of exogenous donor cells and the lack of adequate vascularity to maintain vitality of the newly regenerated tissues. To address these limitations, current advanced tissue engineering techniques gear toward harnessing a biomimetic scaffold that provides a synthetic regenerative microenvironment to support natural tissue regeneration and angiogenesis . In addition to providing physical support, the ideal biomimetic scaffold would preferably also deliver bioactive factors, which instruct endogenous stem cell recruitment and differentiation three-dimensionally and in a controlled manner  (Figure 20.1). Various bioactive factors, including growth factors [6–8], nucleic acids , and integrin-binding ligands , have successfully been delivered or presented on biodegradable scaffolds. Among these, growth factors are the most important soluble signals in the natural regenerative microenvironment, being actively involved in stem cell recruitment, proliferation, and differentiation, angiogenesis, and tissue morphogenesis. Although they are potent, growth factors are expensive and have short half-lives in vivo. Therefore, scaffolds with controlled-release capacity are desired in order to preserve growth factor bioactivity and to prolong their function at therapeutic levels over an extended time period. However, there remain significant challenges in delivering growth factors effectively from scaffolds, including the need to preserve the bioactivity of growth factors during the possibly harsh incorporation process, the control of their release over an extended period during tissue regeneration, and the need for release to be restricted locally so as to avoid toxic or unwanted systemic side effects. Additionally, each individual delivery strategy is related, and sometimes restricted, to the type of scaffold utilized.
Self-exciting point processes (SEPPs), or Hawkes processes, have found applications in a wide range of fields, such as epidemiology, seismology, neuroscience, engineering, and more recently financial econometrics and social interactions. In the traditional SEPP models, the baseline intensity is assumed to be a constant. This has restricted the application of SEPPs to situations where there is clearly a self-exciting phenomenon, but a constant baseline intensity is inappropriate. In this paper, to model point processes with varying baseline intensity, we introduce SEPP models with time-varying background intensities (SEPPVB, for short). We show that SEPPVB models are competitive with autoregressive conditional SEPP models (Engle and Russell 1998) for modeling ultra-high frequency data. We also develop asymptotic theory for maximum likelihood estimation based inference of parametric SEPP models, including SEPPVB. We illustrate applications to ultra-high frequency financial data analysis, and we compare performance with the autoregressive conditional duration models.
We report on the direct synthesis of multi-layer boron nitride nanosheets (BNNSs) and their electron microscopic characterization. The synthesis process is carried out by irradiating hexagonal boron nitride (h-BN) target using short laser pulses. Scanning electron microscopy showed large area (≈50×50 μm2) flat layers of BNNSs transparent to the electron beam. Low magnification transmission electron microscope (TEM) is used to characterize different areas of nanosheets. TEM revealed that each individual nanosheet is composed of several layers. High resolution TEM (HRTEM) measurements confirmed the layered structure. HRTEM analysis of the edge of a nanosheet showed 10 layers from which we obtained the thickness (3.3nm) of an individual nanosheet. Selected area electron diffraction pattern indicated polycrystalline structure of nanosheets. Raman spectroscopy clearly identified E2g vibrational mode related to h-BN.
A CO2-pulsed laser plasma deposition (CO2-PLD) system is installed and used for the quick synthesis of various hexagonal boron nitride (h-BN) and zinc oxide (ZnO) nanostructures. Each part of the CO2-PLD system, such as focusing of laser beam on the target surface, sample holder, shutter, heater, type of the gas, and gas flow rate, can be easily controlled independently to fit different experimental conditions. After installation of the system, a series of experiments were conducted using hBN and ZnO targets. Scanning electron microscopy images showed that the entire surface (2 × 2 cm2) of the substrate is covered with the conical- and disk-shaped BN nanostructures and web-like highly dense ZnO nanowires, indicating a significantly short-time approach to grow mass product nanostructures. Raman spectroscopy identified the hexagonal structure of the synthesized samples.
We report the installation and performance evaluation of a probe aberration-corrected high-resolution JEOL JEM-ARM200F transmission electron microscope (TEM). We provide details on construction of the room that enables us to obtain scanning transmission electron microscope (STEM) data without any evident distortions/noise from the external environment. The microscope routinely delivers expected performance. We show that the highest STEM spatial resolution and energy resolution achieved with this microscope are 0.078 nm and 0.34 eV, respectively. We report a direct comparative evaluation of the performance of this microscope with a Schottky thermal field-emission gun versus a cold field-emission gun. Cold field-emission illumination improves spatial resolution of the high current probe for analytical spectroscopy, the TEM information limit, and the electron energy resolution compared to the Schottky thermal field-emission source.