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Abstract As the demand for the neuromorphic vision system in image recognition experiences rapid growth, it is imperative to develop advanced architectures capable of processing perceived data proximal to sensory terminals. This approach aims to reduce data movement between sensory and computing units, minimizing the need for data transfer and conversion at the sensor‐processor interface. Here, an optical neuromorphic synaptic (ONS) device is demonstrated by homogeneously integrating optical‐sensing and synaptic functionalities into a unified material platform, constructed exclusively by all‐inorganic perovskite CsPbBr3 quantum dots (QDs). The dual functionality of each unit within the ONS device, which can be operated as either an optical sensor or a synaptic device depending on applied electrical polarity, provides significant advantages over previous heterogeneous integration methods, particularly regarding material selection, structural compatibility, and device fabrication complexity. The ONS device exhibits distinct wavelength responses essential for emulating colored image recognition capability inherent in the human visual system. Additionally, the seamless integration of electronics and photonics within a unified material system establishes a novel paradigm for optical retrieval, enabling real‐time perception of the encoded status of the ONS device. These findings represent substantial advancements in near‐sensor computing platforms and open a new horizon for all‐inorganic perovskite optoelectronic technologies.

We integrated social network theory with conservation of resource theory to predict that workplace friendship network centrality provides service employees with critical psychological resources that foster deep acting: positive affect and positive self-perception. In Study 1, we conducted a survey (N = 105) in a Korean banking firm, revealing that these resources mediate the relationship between workplace friendship network centrality and deep acting. Studies 2 and 3, both experimental studies, investigated the hypothesized causal relationships. In Study 2 (N = 151), we found that workplace friendship network centrality increases the intention toward deep acting. Further, Study 3 (N = 140) confirmed the direct effects of friendship network centrality on positive affect and self-perception. By providing insights into the structural antecedents of emotional labor, we inform managers in service organizations of the value of creating avenues for their employees to form and maintain friendships within the organization.

Despite the importance of transistors in modern electronics, transistor characterization requires expensive instruments that are not affordable for many researchers, engineers and educators. Here, we present software that can control source-meter units (SMUs) for current–voltage (I–V) characterization of field-effect transistors, bipolar junction transistors and general two-terminal devices. The software provides a graphical user interface that allows the user to perform parameter setup, real-time data plotting and data management with ease. By simultaneously controlling multiple SMUs with user-friendly interfaces, the developed software provides a more affordable option for the characterization of basic electrical elements, which can benefit research and educational activities related to electronics.

Meat consumption per capita in South Korea has steadily increased over the last several years and is predicted to continue increasing. Up to 69.5% of Koreans eat pork at least once a week. Considering pork-related products produced and imported in Korea, Korean consumers have a high preference for high-fat parts, such as pork belly. Managing the high-fat portions of domestically produced and imported meat according to consumer needs has become a competitive factor. Therefore, this study presents a deep learning-based framework for predicting the flavor and appearance preference scores of the customers based on the characteristic information of pork using ultrasound equipment. The characteristic information is collected using ultrasound equipment (AutoFom III). Subsequently, according to the measured information, consumers’ preferences for flavor and appearance were directly investigated for a long period and predicted using a deep learning methodology. For the first time, we have applied a deep neural network-based ensemble technique to predict consumer preference scores according to the measured pork carcasses. To demonstrate the efficiency of the proposed framework, an empirical evaluation was conducted using a survey and data on pork belly preference. Experimental results indicate a strong relationship between the predicted preference scores and characteristics of pork belly.

The chemical vapor deposition of hexagonal boron nitride layers from BCl3 and NH3 is highly beneficial for scalable synthesis with high controllability, yet multiple challenges such as corrosive reaction or by-product formation have hindered its successful demonstration. Here, we report the synthesis of polycrystalline hexagonal boron nitride (h-BN) layers on copper foil using BCl3 and NH3. The sequential pulse injection of precursors leads to the formation of atomically thin h-BN layers with a polycrystalline structure. The relationship between growth temperature and crystallinity of the h-BN film is investigated using transmission electron microscopy and Raman spectroscopy. Investigation on the initial growth mode achieved by the suppression of precursor supply revealed the formation of triangular domains and existence of preferred crystal orientations. The possible growth mechanism of h-BN in this sequential-pulsed CVD is discussed.

Piezoelectric devices transduce mechanical energy to electrical energy by elastic deformation, which distorts local dipoles in crystalline materials. Amongst electromechanical sensors, piezoelectric devices are advantageous because of their scalability, light weight, low power consumption, and readily built-in amplification and ability for multiplexing, which are essential for wearables, medical devices, and robotics. This paper reviews recent progress in active piezoelectric devices. We classify these piezoelectric devices according to the material dimensionality and present physics-based device models to describe and quantify the piezoelectric response for one-dimensional nanowires, emerging two-dimensional materials, and three-dimensional thin films. Different transduction mechanisms and state-of-the-art devices for each type of material are reviewed. Perspectives on the future applications of active piezoelectric devices are discussed.

We report the growth of GaN micro-rods and coaxial quantum-well heterostructures on graphene films, together with structural and optical characterization, for applications in flexible optical devices. Graphene films were grown on Cu foil by means of chemical vapor deposition, and used as the substrates for the growth of the GaN micro-rods, which were subsequently transferred onto SiO2/Si substrates. Highly Si-doped, n-type GaN micro-rods were grown on the graphene films using metal–organic chemical vapor deposition. The growth and vertical alignment of the GaN micro-rods, which is a critical factor for the fabrication of high-performance light-emitting diodes (LEDs), were characterized using electron microscopy and X-ray diffraction. The GaN micro-rods exhibited promising photoluminescence characteristics for optoelectronic device applications, including room-temperature stimulated emission. To fabricate flexible LEDs, InxGa1–xN/GaN multiple quantum wells and a p-type GaN layer were deposited coaxially on the GaN micro-rods, and transferred onto Ag-coated polymer substrates using lift-off. Ti/Au and Ni/Au metal layers were formed to provide electrical contacts to the n-type and p-type GaN regions, respectively. The micro-rod LEDs exhibited intense emission of visible light, even after transfer onto the flexible polymer substrate, and reliable operation was achieved following numerous cycles of mechanical deformation.

Bandgap engineering in a single material along the axial length of nanowires may be realized by arranging periodic twinning, whose twin plane is vertical to the axial length of nanowires. In this paper, we report the effect of twin on photoluminescence of ZnSe nanowires, which refers to the bandgap of it. The exciton-related emission peaks of transverse twinning ZnSe nanowires manifest a 10-meV-blue-shift in comparison with those of longitudinal twinning ZnSe nanowires. The blue-shift is attributed to quantum confinement effect, which is influenced severely by the proportion of wurtzite ZnSe layers in ZnSe nanowires. [ABSTRACT FROM AUTHOR]

The article reports large-scale and multiplexed tactile sensors with submillimeter-scale shear sensation and autonomous and real-time closed-loop grip adjustment. It mentions the scalable tactile sensor arrays on flexible substrates with high spatiotemporal resolution enabling slip and grip for closed-loop robotics.

This paper explores why and how organizations respond to external pressures for institutional change in terms of organizational political dynamics. The focus on organizational political dynamics is important in understanding a period of institutional change when multiple groups of actors are involved in the dynamic political processes of promoting each group's goals, interests, ideologies, and institutional logic. We propose a social movement framework of organizational political dynamics that focuses on political interactions between two sets of actors--incumbents and challengers--in an organization to explain the micro-foundation underlying the decline and emergence of organizational practices in an organizational field. A longitudinal study of changes in the presidential selection systems of Korean universities illustrates how organizational political dynamics between incumbents (a board of trustees at a private university or government agents at a public university) and challengers (faculty councils) shaped the process of replacing the conventional appointment system with a new system of direct voting during the period 1985 to 2002. The general implications for organizational political dynamics, institutional change, differences in organizational responses to external pressures, and micro foundations of macro institutional phenomena are discussed. [ABSTRACT FROM AUTHOR]

We introduce the concept of group social capital--the set of resources made available to a group through members' social relationships within the social structure of the group and in the broader formal and informal structure of the organization. We argue that greater group social capital resources lead to greater group effectiveness and that there are many different conduits through which group social capital resources flow. We present a multilevel, multidimensional model arguing that an optimal balance of all these conduits maximizes group social capital resources and group effectiveness. [ABSTRACT FROM AUTHOR]

We introduce the construct of network inertia, referring to a persistent organizational resistance to changing interorganizational network ties or difficulties that an organization faces when it attempts to dissolve old relationships and form new network ties. Previous research has neglected the process of network change in favor of an emphasis on identifying beneficial content effects of networks. We emphasize the constraints on network change and propose a multilevel conceptual model relating key sources of network inertia to changes in network ties. We also discuss the implications of network inertia for the evolution of networks. [ABSTRACT FROM AUTHOR]

This study introduces the concept of group social capital, which is the configuration of group members' social relationships within a group and in the social structure of a broader organization, and tests the proposition that group effectiveness is maximized via optimal configurations of different conduits for such capital. These conduits include intragroup closure relationships and bridging relationships that span vertical and horizontal intergroup boundaries. Results from our 60-team field study of informal socializing ties provide empirical support. [ABSTRACT FROM AUTHOR]

We grew and characterized zinc oxide (ZnO) nanolasers on graphene films. By using graphene as a growth medium, we were able to prepare position-controlled and vertically aligned ZnO nanotube lasers. The ZnO nanolasers grown on graphene films showed good optical characteristics, evidenced by a low lasing threshold. Furthermore, the nanolaser/graphene system was easily lifted off the original substrate and transferred onto foreign substrates. The lasing performance was observed to be significantly enhanced by depositing a layer of silver on the back of the graphene film during this transfer process, which was quantitatively investigated using finite-difference time-domain simulations. Due to the wide selection of substrates enabled by the use of graphene films, our results suggest promising strategies for preparing practical nanolasers with improved performance. [ABSTRACT FROM AUTHOR]

Lasing from long semiconductor nanorods is dictated by Fabry-Perot (FP) resonances whereas that from large-diameter microrods is determined by whispering gallery modes (WGMs). Lengths and diameters intermediate between the two systems represent an important size regime for photonics and electronics, but have not been studied in detail. Here, we report on the detection of FP and WGM lasing emissions from a single GaN microrod, and demonstrate the ability to switch between the two lasing mechanisms by translating the excitation beam along the microrod. The competition between FP and WGM-type lasing was studied by finite-difference time-domain simulation and statistical analysis by measuring microrods of various diameters. Finally, control over the relative lasing intensities originating from either FPs or WGMs was demonstrated by tuning the polarization of the emission. [ABSTRACT FROM AUTHOR]

In this paper, we describe a new method for the selective extraction and quantification of glutathione (GSH) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and maleimide-presenting gold nanoparticles (Mal-AuNPs). Our strategy utilizes the Michael addition to selectively extract GSH, from chosen samples, onto the maleimide of Mal-AuNPs. After the extraction step, the GSH bound to the AuNPs was analyzed by MALDI-TOF MS in the presence of an internal standard which was prepared by reacting Mal-AuNPs with isotope-labeled GSH (GSH*). The GSH* has the same structure as GSH but a higher molecular weight, and therefore, enables absolute quantification of GSH by comparing the mass signal intensities of the GSH- and GSH*-conjugated alkanethiols. Our strategy was verified by analyzing GSH- spiked fetal bovine serum and NIH 3T3 cells. [ABSTRACT FROM AUTHOR]

Four published reanalyses of part of the celebrated medical innovation data focus on network effects on the diffusion of tetracycline. Each reanalysis rejects the findings of the previous analysis. This article shows that in the early 1950s, when the original data were collected, private practice physicians, swamped by demand, but facing threats to their autonomy from the federal government and from university medical centers, struggled to keep up with new therapies and relied on colleagues and friends within the profession for help and advice. This article examines the reanalyses' judgment calls concerning the use of a psychophysics power function, the employment of a time-sensitive model, the imputation and exclusion of data, and the addition of new variables. Given the radical undecidability of numerical evidence in the absence of context, the reanalysis of stand-alone data is likely to produce a continuing series of conflicting results. [ABSTRACT FROM AUTHOR]

Photoluminescence spectrum is a powerful tool to investigate the excitonic and defect-related information in condensed phase materials. Through temperature-dependent photoluminescence spectra, heavy- and light-hole free excitons, and the exciton bound to a neutral donor and the accompanied LO-phonon replicas of the zinc blende ZnSe are observed and verified in ZnSe-based longitudinal twinning nanowires. In the deep-level emission region, two peaks at 1.979 and 2.315 eV are attributed to the donor–acceptor–pair recombination and the acceptor impurity of Au, respectively. [ABSTRACT FROM AUTHOR]