Inverted Pyramid Research Articles

Innovating Online Journalism: New Ways of Storytelling

ABSTRACT Journalism faces a number of challenges: patterns of news consumption have changed and audiences for traditional news outlets are declining. In this context, we explore whether the “inverted pyramid” model – a system of news writing that arranges facts in descending order of importance, which remains predominant in journalism – is the most effective way of communicating information online. Based on a mixed-methods approach using qualitative data from workshops and expert consultations, we developed a series of new “prototypes” of online news storytelling and tested them with a wide range of audiences (N = 1268). Building on earlier work, we find that linear forms of storytelling - rarely used in news - are more effective in transferring knowledge to news consumers and are seen as more engaging, convenient and useful than the traditional inverted pyramid. We then identified key principles that should underlie a more user-focussed approach to narratives in online news.

Reduction of dislocation density in single crystal diamond by Ni-assisted selective etching and CVD regrowth

The development of large-area diamond films with low dislocation density plays a key role in diamond-based devices. In this study, we present a straightforward and reasonably priced Ni-assisted etching and re-growth method to decrease the dislocation density of diamond. By adjusting the annealing temperature, a high-density inverted pyramid and/or trapezoidal pit can be effectively exposed because the interaction between carbon and Ni metal. The Ni tends to dissolve the diamond surrounding the dislocation at high temperature while maintaining the surface's flatness. The precipitated graphite layer is removed using wet etching, and the step flow mode is then restored via the re-growth procedure. It shows that the dislocations located beneath the etching pits are partially annihilated during the lateral coalescence, resulting in a decrease in dislocation density.

Performance Improvement of InGaN Red Light‐Emitting Diode by Using V‐Pits Layer and Step‐Graded GaN Barrier

The carrier‐transport properties of InGaN red light‐emitting diode (LED) with V‐pits layer and step‐graded GaN barrier are investigated. By using V‐pits layer technology, the inverted pyramid–shaped V‐pit layer forms an energy barrier around the dislocation, inhibits the lateral diffusion of electrons from active layer to the dislocation center, and reduces the probability of non‐radiative recombination rate of electrons and holes. With the increase of the horizontal opening width of the V‐pits layer, the uniformity of holes concentration distribution in InGaN/GaN multiple quantum well (MQWs)‐active region is improved significantly. Compared with the traditional InGaN/GaN MQWs‐active region with fixed well/barrier thickness, step gradient GaN barrier is adopted in the active layer of InGaN red LED, which can reduce the length of the transmission path and improve the injection efficiency of holes into deep quantum wells close to the n‐type region. At injection current density of 200 A cm−2, the internal quantum efficiency of LED D with V‐pits layer and step‐graded GaN barrier is improved by 56.4% as compared with that of reference LED A. In addition, the efficiency droop of LED D can also be effectively alleviated as compared with that of reference LED A.

Optical Design Impact on PERC Solar Cell Efficiency: Upright Pyramids vs Inverted Pyramids Textured Surfaces

Aims: Textured surfaces morphology on solar cell are benefited to minimize the reflection. Many configurations are used for solar cell manufacturing. The ray’s simulators are used in this work. The gains (photogeneration) and losses (reflection, transmission, parasitic absorption) are recorded for each ray. The global gains and losses are determined by averaging many rays. With a sufficiently large number of rays, the Monte Carlo simulation converges to the physical model. The Monte-Carlo algorithm employed by the Wafer Optics Calculator necessarily results in output uncertainties. These uncertainties are calculated by dividing the user-requested number of rays into several sub-simulations, then applying statistical analysis to the set of sub-simulations to arrive at a mean value and 95% confidence interval (about two standard deviations). The calculators weight the magnitudes by the photon flux in the user-defined spectrum, then integrates over the wavelength, to calculate photon current density. The photogenerated current JG in a wafer equates to the short circuit current that could be extracted from a perfect solar cell made from the wafer. This work focuses on two textured surfaces morphology such that, upright pyramids, and inverted pyramids. To show their impact in solar cell efficiency. Which involve evaluating the external reflection for both surface morphology. Also compare the photogeneration JG absorbed by the substrate.

Land carbon metabolism in Xiamen-Zhangzhou-Quanzhou region based on ecological network analysis.

Discovering the underlying mechanisms between carbon metabolism and carbon balance of human-natural system is of important theoretical and practical significance for reducing regional carbon emissions and promoting low-carbon development. Taking Xiamen-Zhangzhou-Quanzhou region from 2000 to 2020 as an example, we constructed the framework of spatial network model of land carbon metabolism based on carbon flow, and inquired into the spatial and temporal heterogeneity in the carbon metabolic structure, function and ecological relationships by using the ecological network analysis. The results showed that the dominant negative carbon transitions related with land use changes came from the conversion of cultivated land to industrial and transportation land, and that the high value areas of negative carbon flow were mainly distributed in the areas with relatively developed industries in the middle and east parts of Xiamen-Zhangzhou-Quanzhou region. Competition relationships were the dominant type and the spatial expansion was obvious, which led to the decreases of the integral ecological utility index and affected the regional carbon metabolic balance. The ecological network hierarchy of driving weight changed from a pyramid structure to a relatively more regular structure, with the producer contributing the most. The ecological network hie-rarchy of pull weight changed from a pyramid structure to an inverted pyramid structure, mainly due to the excessive increase of industrial and transportation land weights. Low-carbon development should focus on the sources of negative carbon transitions caused by land use conversion and its comprehensive impacts on carbon metabolic balance, to formulate differentiated low-carbon land use patterns and carbon emission reduction policies.

Experimental Study for Load-Settlement Behavior of Flat and Shell Footings on Sandy Silt Soil

Shell foundations are often used to raise the carrying capacity of a structure on weak soils. In cases where large superstructure loads must be transferred to poorer soils, shell foundations are more cost-effective than ordinary shallow foundations. Advances in the study and design of shell-type foundations have shown their superiority over traditional footings in poorer soils. The current study aims to investigate shell shape’s influence on ultimate load capacity. Seven footing types’ models were created along with an appropriate testing box. The soil needed for the study was from the region north of Mosul city, classified as silt with low plasticity (sandy silt) soil. A laboratory model experimentally determined the ultimate load capacities for inverted and upright conical, inverted and upright pyramid, and hemispherical shell foundations on silty soil. The achieved results were associated with those for conventional flat squares and circles. According to the findings, the “upright conical” shell footing has a load capacity of 12.7 kN, higher than the other foundations, and its efficiency was 51%. When comparing foundations, the “upright pyramidal” shell footing has better settling characteristics and a settlement factor of 0.017. As the shell factor decreases, the shell foundation begins to behave more like a flat foundation, which reduces the maximum load capacity of the shell foundation.

Technological Advances Affect Journalists' Reporting Styles

This study focuses on exploring how journalists' reporting style is affected by the continuous development of emerging technologies. This paper analyzes how journalists' reporting styles are affected by technological advances by analyzing four reporting styles in the digital domain. On the other hand, it also puts forward new requirements for current journalists to constantly learn and have digital skills. From a macro point of view, the change in reporting methods also positively impacts current journalism and journalists. For example, in data journalism, journalists introduce different data to support the validity of the news. It enables readers to understand important information about the content of the news, based on the fact that data is added to support the news. At the level of narrative journalism style, journalists are increasingly using news stories to attract readers and expose them to real news sources. In the case of interactive journalism, this style of journalism (such as news games) has been shown to help journalists run news stories smoothly and meet the needs of readers. In inverted pyramid journalism, some journalists stick to this style, for the obvious reason that it allows readers to get to key news content in a concise and clear way. This is undoubtedly positive.

Upright pyramids vs. inverted pyramids surface textures: a comparative investigation on the electrical properties of PERC solar cells

Upright pyramids vs. inverted pyramids surface textures: a comparative investigation on the electrical properties of PERC solar cells

Sympetalous defects in metalorganic vapor phase epitaxy (MOVPE)-grown homoepitaxial β-Ga2O3 films

We report a new type of structural defect in β-Ga2O3 homoepitaxial thin films grown by metalorganic vapor phase epitaxy, which we have dubbed as “sympetalous defects.” These consist of a line defect (for example, a nanotube defect) in the underlying substrate combined with a multi-faceted inverted polycrystalline pyramid in the epitaxial film, which may also be decorated with twinned polycrystalline grains. In plan-view atomic force, scanning electron, or optical microscopies, the sympetalous defects appear similar in shape to polygonal etch pits observed for single crystals. Photoluminescence microscopy exposed spots of polarization-dependent luminescence at these defects, different from the single crystal films' luminescence. Furthermore, some of the defects exhibited circular dichroism in their luminescence that we correlated with partial helices formed within the pits by the arrangement of linearly dichroic polycrystalline grains. Finally, the density of sympetalous defects agrees with the etch pit densities of the substrates. Understanding and controlling these defects will be of importance as they modify the local properties of films, affect fabricated device yields, and influence characterization experiments.

Detection and Characterization of Nodularin by Using Label-Free Surface-Enhanced Spectroscopic Techniques.

Nodularin (NOD) is a potent toxin produced by Nodularia spumigena cyanobacteria. Usually, NOD co-exists with other microcystins in environmental waters, a class of cyanotoxins secreted by certain cyanobacteria species, which makes identification difficult in the case of mixed toxins. Herein we report a complete theoretical DFT-vibrational Raman characterization of NOD along with the experimental drop-coating deposition Raman (DCDR) technique. In addition, we used the vibrational characterization to probe SERS analysis of NOD using colloidal silver nanoparticles (AgNPs), commercial nanopatterned substrates with periodic inverted pyramids (KlariteTM substrate), hydrophobic Tienta® SpecTrimTM slides, and in-house fabricated periodic nanotrenches by nanoimprint lithography (NIL). The 532 nm excitation source provided more well-defined bands even at LOD levels, as well as the best performance in terms of SERS intensity. This was reflected by the results obtained with the KlariteTM substrate and the silver-based colloidal system, which were the most promising detection approaches, providing the lowest limits of detection. A detection limit of 8.4 × 10-8 M was achieved for NOD in solution by using AgNPs. Theoretical computation of the complex vibrational modes of NOD was used for the first time to unambiguously assign all the specific vibrational Raman bands.

ANALYSIS OF TEMPO AND KOMPAS ONLINE MEDIA FRAMING TOWARDS REPORTING THE ISSUES OF THE 2024 PRESIDENTIAL ELECTION POSTPONEMENT

Abstract: The purpose of this study is to find out how one of the reports made by the online media Tempo and Kompas in framing news about the postponement of the 2024 election through the framing analysis approach of the Zhongdang Pan and Gerald M. Kosicki model. The method used is descriptive-interpretative research. Researchers interpret news about the issue of delaying the 2024 presidential election by taking news samples from the online media Tempo and Kompas which were published on April 10 and 12, 2022. The results of this study are 1) News carried out by Tempo tend to be neutral and as it is, in contrast to Kompas which include opinions from political communication experts 2) both news stories have used inverted pyramid systematics. It can be seen from the leads in both news. The difference is that Tempo media reports tend to be short but dense, while Kompas is quite long because it adds news content by including opinions from political communication experts.

Rational construction of Prussian blue analogue with inverted pyramid morphology as ultrastable cathode material for lithium-ion battery

Prussian blue analogue material is regarded as an ideal cathode candidate for Li-ion batteries due to its open 3D frame structure and various transition metals with different valence states. However, poor electronic conductivity and structural collapse severely limit its application in the electrochemical field. In this work, Na1.13Fe[Fe(CN)]6·3.22H2O electrode materials with stepwise hollow inverted pyramid morphology are prepared by simple hydrothermal method. The inverted pyramid Na1.13Fe[Fe(CN)]6·3.22H2O maintains the stability of the crystal structure and slows down the volume expansion during the Li + insertion-extraction process. Benefiting from the unique structure and composition, the discharge specific capacities of the optimal Na1.13Fe[Fe(CN)]6·3.22H2O electrode (FeHCF-2) are 153.7, 126.28, 119.4 and 113.4, 107.61, 102.52 and 92.46 mAh·g−1 at 0.1, 0.3, 0.5, 1, 2, 5 and 10 C, respectively. The first discharge capacity of FeHCF-2 electrode at 1 C is 111.88 mAh·g−1, and the discharge capacity of FeHCF-2 electrode is 115.04 mAh·g−1 after 1000 cycles, indicating that FeHCF-2 electrode has ultrastable cycle stability. Therefore, designing the hollow inverted pyramid morphology can be regarded as an available way to enhance the electrochemical activity of Na1.13Fe[Fe(CN)]6·3.22H2O for advanced lithium-ion batteries, and effective design strategies can be used for the modification of other cathode materials for Li-ion batteries.

Broadband absorber coupled with anti-reflection inverted pyramid type all-dielectric microstructure

In order to improve the absorption efficiency and absorption bandwidth, we propose an inverted pyramid type all-dielectric absorber. Using the anti-reflection interface characteristics of the inverted pyramid microstructure, the designed absorber can achieve 100% perfect absorption in the range of 1.5THz to 1.7THz. Based on the structural diffraction analysis and electromagnetic field distribution characteristics, we have deeply explored the physical mechanism of wave absorption of the designed structure, and revealed the dual physical mechanism of electromagnetic wave diffraction conversion and resonance absorption. Based on the unique wet etching technology, we have experimentally prepared this inverted pyramid type all-dielectric absorber. Through experimental measurement, the consistency of the theoretical design and experimental test was confirmed.

Inverted pyramid structure on monocrystalline silicon processed by wet etching after femtosecond laser machining in air and deionized water

The micro-structured silicon has been preliminarily applied to improve the surface and optical properties of micro-solar cells, micro-optical systems, and aerospace engineering. However, the morphological changes and optical properties of monocrystalline silicon during femtosecond laser machining assisted with chemical etching are not clear, especially in a liquid environment. In this paper, monocrystalline silicon was ablated by femtosecond laser in air and deionized water respectively and then etched by alkaline potassium hydroxide (KOH). The reflectivity, absorptivity, and transmissivity of monocrystalline silicon were tested. Experimental results showed that inverted pyramid (IP) structure could be processed on a monocrystalline silicon wafer by ablating the surface with a high-power laser under the air environment and a low-power laser under the deionized water environment, followed by KOH etching. Meanwhile, the optical properties of the monocrystalline silicon with IP structure were effectively improved.

Comprehensive cell to module optical loss analysis of metal assisted chemically etched inverted pyramid textured multi-crystalline silicon solar cells and modules by ray-tracing method

Most of the recent articles addressing the texturing issues of diamond wire sawn multi-crystalline silicon (mc-Si) wafers propose metal-assisted chemical etching (MACE) inverted pyramid texturing scheme as the best suited industrial process for the fabrication of low-cost, high efficiency solar cells. However, a detailed generation loss analysis of such textured solar cells are not widely investigated yet, especially after module conversion. We present a comprehensive analysis of various optical losses in MACE inverted pyramid textured mc-Si solar cells and modules using the SunSolve module ray-tracer simulator from PV Lighthouse. The simulation model accurately predicted the optical properties of MACE inverted pyramid textured samples and the simulated reflectance values were nearly identical to experimentally measured values at different stages of solar cell processing (before and after ARC). This study quantifies and benchmarks the optical generation losses of not-encapsulated and encapsulated inverted pyramid textured cells with well established models of random pyramid textured and iso-textured solar cells for aluminum back surface field (Al-BSF) architecture. Moderate cell to module (CTM) generation current loss was noticed for inverted pyramid textured solar cells, which was nearly 0.71 mA-cm−2 lower than random pyramid textured and 1.05 mA-cm−2 higher than iso-textured solar cells. We find that adoption of MACE inverted pyramid texturing over acid texturing enhances the photo-generation in mc-Si modules by ∼0.5% and that the total photo-generation current density in mc-Si solar modules approach 99.6% of that in random pyramid textured c-Si modules.

Optical simulation of CsPbI3/TOPCon tandem solar cells with advanced light management

Monolithic perovskite/Si tandem solar cells (TSCs) have experienced rapid development in recent years, demonstrating its potential to exceed the Shockley–Queisser limit of single junction Si solar cells. Unlike typical organic-inorganic hybrid perovskite/silicon heterojunction TSCs, here we propose CsPbI3/TOPCon TSC, which is a promising architecture in consideration of its pleasurable thermal stability and good compatibility with current PERC production lines. The optical performance of CsPbI3/TOPCon TSCs is simulated by the combination of ray-tracing method and transfer matrix method. The light management of the CsPbI3/TOPCon TSC begins with the optimization of the surface texture on Si subcell, indicating that a bifacial inverted pyramid with a small bottom angle of rear-side enables a further minimization of the optical losses. Current matching between the subcells, as well as the parasitic absorption loss from the front transparent conductive oxide, is analyzed and discussed in detail. Finally, an optimized configuration of CsPbI3/TOPCon TSC with a 31.78% power conversion efficiency is proposed. This work provides a practical guidance for approaching high-efficiency perovskite/Si TSCs.

Towards high-efficiency Al-BSF c-Si solar cell with both superior omnidirectional and electrical performance by modulating the tilt angle of quasi-periodic inverted pyramid arrays

Seeking efficient light trapping structures with both superior omnidirectional and electrical performance is always on the way for increasing electrical energy output of c -Si solar cell over a wide range of light incident angle (θ). Here, tile angle (δ) of quasi-periodic structure arrays is systematically modulated from 35.9° to 72.8° on diamond-wire-sawn (DWS) c -Si by a simple and cost-effective Cu and Ni co-assisted chemical etching way followed by a post treatment. Interestingly, compared with the conventional micro pyramid (MP), the optimized inverted pyramid (IP) like arrays with a δ of 64° possess both lower light reflectance and carrier recombination, leading to a corresponding solar cell with a higher efficiency (∼19.67%) than that of MP based counterpart (∼19.31%). Moreover, during the increase of θ, the external quantum efficiency (EQE) of 64° IP based cell drops much more slowly than that of MP based one by properly adjusting the relative position of the structure arrays and incident light, indicating its omnidirectional property. Simultaneously, a maximum relative enhancement of electrical output power approaching ∼5.8% in the θ range of −90°–90° is achieved on 64° IP based cell compared to the MP based one, the mechanism behind which is further explained by optical simulation. The above finds pave a new way to increase the electrical energy output in a simple and cost-effective way. • Tilt angle control of quasi-periodic IP was achieved by varying Cu and Ni ratio. • 0.36% absolute increase in solar cell efficiency was made based on 64° IP. • ∼5.8% relative increase of output power was achieved on 64° IP based cell. • Mechanism behind omnidirectional performance was explained by optical simulation.

Processing at the Edge: A Case Study with an Ultrasound Sensor-Based Embedded Smart Device

In the current context of the Internet of Things, embedded devices can have some intelligence and distribute both data and processed information. This article presents the paradigm shift from a hierarchical pyramid to an inverted pyramid that is the basis for edge, fog, and cloud-based architectures. To support the new paradigm, the article presents a distributed modular architecture. The devices are made up of essential elements, called control nodes, which can communicate to enhance their functionality without sending raw data to the cloud. To validate the architecture, identical control nodes equipped with a distance sensor have been implemented. Each module can read the distance to each vehicle and process these data to provide the vehicle’s speed and length. In addition, the article describes how connecting two or more CNs, forming an intelligent device, can increase the accuracy of the parameters measured. Results show that it is possible to reduce the processing load up to 22% in the case of sharing processed information instead of raw data. In addition, when the control nodes collaborate at the edge level, the relative error obtained when measuring the speed and length of a vehicle is reduced by one percentage point.

Efficient infrared sunlight absorbers based on gold-covered, inverted silicon pyramid arrays

Arrays of gold-covered inverted silicon pyramids exhibit strong light absorption in the near infrared and large field enhancements at hot spots, due to resonant excitation of surface-plasmon polaritons at the metal/dielectric interface.

Ultrathin Bifacial Passivated Emitter and Rear Cell with Inverted Pyramid Textures

Wafer thinning is a crucial technique for high‐efficiency solar cells. Herein, an inverted pyramid (IP) texture is prepared on a 35 μm‐thick flexible silicon (Si) wafer with a standard area of 156 × 156 mm2. Based on the experimental results, an ultrathin bifacial passivated emitter and rear cell (PERC) with IP textures using PC1D simulation is designed. The influence of wafer thickness, IP texture, bifacial structure, thickness of the antireflection coating, and doping concentration on device performance is investigated. The results show that the ultrathin IP‐based bifacial PERC possesses better output performance than the traditional cell. Finally, a simulated maximum efficiency of 23.44% is obtained using PC1D software, with an open‐circuit voltage of 0.7127 V and a short‐circuit current of 9.272 A. This ultrathin PERC with IP textures provides an effective way to improve the efficiency of ultrathin silicon solar cells.