Layout Pattern Research Articles

Modeling and Analysis of the Cleaning System of a Reconfigurable Tiling Robot

Cleaning robots have been gaining traction amongst various industries globally, with domestic floor cleaning robots being the most widespread. These robots usually employ brushes with a vacuum unit for dry cleaning purposes. For a self-reconfigurable tiling-based floor cleaning robot, hTetro, a modular sweeping module was developed. This robot consists of four rectangular blocks connected via passive hinges and each block consists of a steering unit with two conventional wheels following the differential drive principle. This paper presents the navigation and operational principle of the hTetro robotic platform and the detailed mechanical and hardware design of two different iterations of its cleaning module. The efficiency of these modules was numerically validated via Computational Fluid Dynamics analysis. Using the loading and boundary conditions derived from analytically formulated force analysis, Finite Element based static analysis and modal analysis of the cleaning module were carried out to determine the possible structural deformations, natural frequencies and stress patterns on each bristle and rolling brush. Through these simulations, we demonstrate the safe design of the roller brushes layout and bristle pattern and efficiency of the cleaning module. By deploying the platform in the lab setting and real food court environment, we verify the cleaning performance of the platform.

Fast Pixelated Lithographic Source and Mask Joint Optimization Based on Compressive Sensing

Pixelated source-mask joint optimization (SMO) plays a crucial role in improving the resolution and image fidelity of optical lithography process. However, the ever growing integration density of semiconductor devices incurs the explosion of data throughput, and poses a considerable challenge on the computational efficiency of pixelated SMO algorithms. This paper proposes to use compressive sensing (CS) to effectively reduce the computational complexity of the SMO algorithm. The proposed SMO algorithm is sequential, where the lithographic source and mask patterns are optimized alternatively. Based on the lithography imaging model, source optimization is transformed to a linear CS reconstruction problem with a nonnegative constraint on the illumination intensity. On the other hand, the problem of mask optimization is solved by a nonlinear CS method aided by sparsity and low-rank regularizations. The dimensionality of the objective function is reduced by downsampling the layout pattern to be printed. The improvement in computational efficiency is verified, and a set of simulations are presented to assess the proposed SMO algorithms. Speedup by several-fold is attained over traditional gradient-based SMO method. Improvement in lithography image fidelity and mask manufacturability is obtained compared to the traditional SMO method and state-of-the-art CS-based SMO method.

Lithography Hotspot Detection with FFT-based Feature Extraction and Imbalanced Learning Rate

With the increasing gap between transistor feature size and lithography manufacturing capability, the detection of lithography hotspots becomes a key stage of physical verification flow to enhance manufacturing yield. Although machine learning approaches are distinguished for their high detection efficiency, they still suffer from problems such as large-scale layout and class imbalance. In this article, we develop a hotspot detection model based on machine learning with high performance. In the proposed model, we first apply an Fast Fourier Transform--based feature extraction method that can compress large-scale layout to a multi-dimensional representation with much smaller size while preserving the discriminative layout pattern information to improve the detection efficiency. Second, addressing the class imbalance problem, we propose a new technique called imbalanced learning rate and embed it into the convolutional neural network model to further reduce false alarms without accuracy decay. Compared with the results of current state-of-the-art approaches on ICCAD 2012 Contest benchmarks, our proposed model can achieve better solutions in many evaluation metrics, including the official metrics.

Reliability Concerns on LDMOS With Different Split-STI Layout Patterns

Compared with the full shallow trench isolation (full-STI) lateral double-diffused MOS (LDMOS), the split-STI LDMOS has been demonstrated as a superior device with better breakdown voltage (BVOFF and specific on-resistance ( ${R}_{ {\scriptstyle\mathrm{ON}},\text {sp}})$ by virtue of its low resistance current path and dielectric reduced surface field effect. The layout of STI may not only be restricted in one pattern. Instead, it can have a variety of changes based on the split-STI structure. Actually, improvement of ${R}_{ {\scriptstyle\mathrm{ON}},\text {sp}}$ can be achieved upon modifying the STI layout pattern. In this way, four STI layout patterns, named split-STI, stair-STI, slope-STI, and H-shape-STI, are proposed. However, there is lack of information about the impacts of STI layout patterns on the reliability features of LDMOS. Therefore, in this article, the reliability features of the LDMOS with different STI layout patterns are investigated in detail, including electrical safe operating area (e-SOA), electro-static discharge (ESD) robustness, and hot carrier injection (HCI) degradation. Combining the experiment and technology computer-aided design (TCAD) simulation, the root causes of different reliability features are analyzed and discussed. Comparing them each, the LDMOS with H-shape-STI is recommended because of its better reliability features.

Fragility Analysis of Infilled Reinforced Concrete Frames Subjected to Near-Field Ground Motions

The present paper deals with the analytical investigation of representative planar masonry-infilled reinforced concrete (MIRC) frames for seismic fragility, performance and demand. The study includes the effect of various patterns of layout for infills panels along the height of reinforced concrete frames. The analytical investigation has been done using non-linear dynamic time-history analysis under collection of forty SAC near-field ground motions using rational hysteretic models for structural components; the results are presented in terms of parameters such as peak inter-storey drift, residual drift and damage index. The outcomes of study are used to develop seismic fragility curves in probabilistic terms for the generic medium-rise MIRC frames. The developed fragility curves can be useful tools in predicting the life and economic losses in the future seismic event. In the current study, efforts are also made to develop curves demonstrating seismic performance and seismic demand for representative MIRC frames.

Simulator-based training of generative neural networks for the inverse design of metasurfaces

Abstract Metasurfaces are subwavelength-structured artificial media that can shape and localize electromagnetic waves in unique ways. The inverse design of these devices is a non-convex optimization problem in a high dimensional space, making global optimization a major challenge. We present a new type of population-based global optimization algorithm for metasurfaces that is enabled by the training of a generative neural network. The loss function used for backpropagation depends on the generated pattern layouts, their efficiencies, and efficiency gradients, which are calculated by the adjoint variables method using forward and adjoint electromagnetic simulations. We observe that the distribution of devices generated by the network continuously shifts towards high performance design space regions over the course of optimization. Upon training completion, the best generated devices have efficiencies comparable to or exceeding the best devices designed using standard topology optimization. Our proposed global optimization algorithm can generally apply to other gradient-based optimization problems in optics, mechanics, and electronics.

Analisis Tata Letak Pabrik dan Pola Aliran Bahan Feronikel di FeNi Plant 3 PT Antam Tbk Unit Bisnis Pertambangan Nikel Sulawesi Tenggara

ABSTRACTNickel industry is one of the industry that potentially to increase foreign exchange. PT Antam Tbk UBPN Southeast Sulawesi has land area about 169.194,937 m2 with 14.452,85 m2 of buildings in FeNi Plant 3. In producing nickel, PT Antam Tbk UBPN Southeast Sulawesi requires a more optimum layout and material flow pattern. The objective of this research was to analyzed the layout of production and material handling in the FeNi Plant 3. The methods used in this study were relationship analysis of production activity and Assembly Line Balancing. The result showed that the current ferronikel flow layout and flow pattern is shaped a straight line, and efficiency assembly line balansing about 71,25 percent.Keywords: assembly line balancing, ferronickel, material flow pattern, layout production.ABSTRAKIndustri pengolahan nikel merupakan salah satu industri yang berpotensi menambah devisa negara. PT Antam Tbk UBPN Sulawesi Tenggara memiliki luas lahan sekitar 169.194,937 m2 dengan luas bangunan di FeNi Plant 3 sekitar 14.452,85 m2. PT Antam Tbk UBPN Sulawesi Tenggara dalam memproduksi nikel memerlukan tata letak dan pola aliran bahan yang lebih optimum. Tujuan penelitian yaitu menganalisis tata letak produksi dan pola aliran bahan feronikel di FeNi Plant 3 serta efisiensi keseimbangan lini perakitan. Metode yang digunakan adalah observasi dan analisis hubungan kedekatan aktivitas produksi dan keseimbangan lini perakitan. Hasil penelitian menunjukkan tata letak dan pola aliran bahan feronikel saat ini berbentuk garis lurus, serta efisiensi keseimbangan lini perakitan sebesar 71,25 persen.Kata kunci: feronikel, keseimbangan lini perakitan, pola aliran bahan, tata letak produksi.

Fast lithographic source optimization method of certain contour sampling-Bayesian compressive sensing for high fidelity patterning.

Fast source optimization (SO) is in demand urgently for holistic lithography on-line at 14-5 nm nodes. Our earlier works of fast compressive sensing (CS) SO methods adopted randomly sampling monitoring pixels on layout patterns, consequently resulting in failure of SO sometimes and poor image fidelity compared to gradient-based SO with complete sampling (SD-SO). This paper proposes a novel certain contour sampling-Bayesian compressive sensing SO (CCS-BCS-SO) method to achieve the goals of fast SO and high fidelity patterns simultaneously. The CCS assures the optimized source uniquely and reduces the computational complexity significantly. The BCS theory, to our best knowledge, is for the first time applied to resolution enhancement techniques (RETs) in lithography systems to ensure high fidelity patterns. The results demonstrate that CCS-BCS-SO simultaneously achieves fast SO like CS-SO and high fidelity patterns like SD-SO.

Traffic impact analysis of inspection area site selection at a foreign trade container terminal

ABSTRACTTo improve the security and efficiency of terminal operations, a key issue for land area layout at a foreign trade container terminal is to plan and design an inspection area. Since it directly affects terminal traffic, while determining inspection area site selection, we should pay a great attention to operations and management of terminal traffic as well as container inspection. This paper employs a system decomposition technique to develop an integrated simulation framework, which enables us to flexibly obtain the whole picture of terminal traffic conditions and evaluate traffic impacts of inspection area site selection. A real-world terminal with typical patterns of land area layout is chosen to carry out a case study, which shows that traffic flow is unevenly distributed on the terminal road network and that the distribution is influenced by truck streams at the terminal. New findings also include: (1) traffic volume at the terminal apron is rather unbalanced in association with the non-continuous utilization of berths; (2) a proper inspection area should be located near the gate if the terminal conditions permit from the perspective of terminal traffic. This work may provide a decision-making reference for the planning and construction of foreign trade container terminals.

Optimization Design of Radiation Vault in Jupiter Orbiting Mission

In Jupiter missions, one significant challenge is the harsh environment. The radiation in Jovian orbit is much higher than that in earth bf vicinity in terms of intensity and energy level. In spacecraft (S/C) design, key electronics are packaged in an enclosed vault to help them survive through the mission. The preliminary optimization design methods of a radiation vault based on a genetic algorithm (GA) are introduced, including shield structure optimization and layout pattern of electronics optimization. In shield structure optimization, the method is combined with a total ionizing dose (TID) evaluation tool. The goal is to find the optimal multi-layer shield structure so that the TID, after the shielding, is minimal within the threshold of the total mass of the structure. In a 1-year mission with an orbit of $10\,\,R_{j}\times 25\,\,R_{j} \times 0^{\circ }$ , if the areal density is within 0.5–3 g/cm2, the optimal structure is bilayer or trilayer with high-Z material as an external layer and low-Z material as an internal layer. This structure benefits from the fact that the low-Z material is more effective in shielding energetic protons whereas the high-Z material is more effective in shielding energetic electrons. In the 1-g/cm2 situation, the optimal structure is a 0.829-mm lead layer combined with a 0.158-mm magnesium layer. Comparing with the traditional aluminum shielding structure, about 43.6% of mass can be saved. In layout pattern optimization, this method combines a packing algorithm and a 3-D TID simulation tool. Using this method, an effective design layout of the vault can be found. In this design, all avionics can survive through the mission. In addition, the mass of the vault is low enough that the layout pattern is acceptable in S/C design. As an example, 14 instruments with TID threshold of 50 krad (Si) are packaged in a vault. On the premise that one instrument’s walls are thickened to 3.5-mm aluminum, the total mass of the vault is 68.47 kg. This method is a starting point for the iterative design of the radiation vault and gives principle guidelines for the designers.

Melanin bleaching with potassium permanganate for melanocytic lesions diagnosis in veterinary medicine

ABSTRACT The aim of this study was to microscopically re-evaluate the melanocytic lesions diagnoses established by the Animal Pathology Laboratory of the Federal University of Uberlândia, in the state of Minas Gerais, Brazil, over a period of eleven years; in addition, to perform a comparative analysis between the conventional histopathological (CH) method and the use of the melanin bleaching (MB) technique with potassium permanganate, sulfuric acid, and oxalic acid solutions. The results of the MB method presented a disagreement in 24.32% of the diagnosis previously by CH, with low agreement (61.0%) and low Kappa coefficient (0.2267). Melanoma was the most frequent lesion, more frequent in elderly and non-breed female dogs. The most frequent melanoma location was in the cutaneous tissue. The presence or absence of a pagetoid spread in cutaneous samples, distribution of melanin, pattern of cell layout, cell morphology, degree of cellular atypia, and the number of mitoses verified after MB were the most important criteria to confirm the diagnosis of malignancy or benignity of the lesions. Evaluating pathologists considered MB to be essential for the majority of diagnoses and an efficient complementary method for the diagnosis of melanocytic lesions, even in cases with a moderate degree of pigmentation.

Profiles and Prevalence’s of Abdominal Obesity Among Dubai Adult Cohort (18-59), the Layout of Margins and Patterns of Associates, Community Based Approach

Profiles and Prevalence’s of Abdominal Obesity Among Dubai Adult Cohort (18-59), the Layout of Margins and Patterns of Associates, Community Based Approach

Profiles and Prevalence’s of Abdominal Obesity Among Dubai Adult Cohort (18-59), the Layout of Margins and Patterns of Associates, Community Based Approach

Profiles and Prevalence’s of Abdominal Obesity Among Dubai Adult Cohort (18-59), the Layout of Margins and Patterns of Associates, Community Based Approach

Fissure evolution of weak-cemented jurassic overburden induced by multiple-seam mining: a case study in Western China

ABSTRACT The coal seams in western China are predominantly formed in the lower Jurassic, with generally low strength and poor cementability, which are markedly different from the coal seams in eastern China. In addition, mining layout has an important impact on the fissure development pattern and height in weak-cemented overburden. Thus, investigating the relationship between fissure development pattern and mining layout is of great significance to mining safety. In this study, the mechanical properties of coal and rock strata in no. 3 mining area of Saier Mine, Xingjiang, China, were tested. And a numerical simulation was performed by using the Universal Distinct Element Code (UDEC) distinct element numerical simulation software. The different working face layout schemes were performed to investigate the variation patterns of overburden fissure development height, and coal pillar stress and deformation. The simulation results indicate that as the δW (ratio of the working face width to coal pillar width) increases, the fissure development height gradually increases and the coal pillar horizontal displacement, vertical stress, and horizontal stress first decrease and then increase. Four empirical equations for computing the fissure development height and the horizontal displacement, vertical stress, and horizontal stress of coal pillars were obtained by using the regression analysis method. What is more, all the correlations between the above independent variables and δW can be expressed as quadratic functions. The equations can not only be used as reference criteria for the working face layout design of A3 coal seam in no. 3 mining area of Saier Mine, but also are of great guiding significance to the safety of multiple-seam mining actions under confined water in western China.

Preliminary Analysis on the Status Quo and Problems of Land Use of Educational Space in Primary and Secondary Schools in the Downtown Area, Tianjin- Results of data analysis based on information entropy and equilibrium

In this article, in order to have a better understanding of the current situation and supply-demand challenges with regard to the land use of educational space in primary and secondary schools in the downtown area, Tianjin and address the related problems, the comparative analysis is conducted on the land-use layout of 30 ordinary primary and secondary schools. In addition, for these primary and secondary schools, based on the information entropy, balance and dominance of land-use structure, and in conjunction with the actual conditions, spatial location and time of construction, efforts are made to analyze the diversity and balance of educational space. Generally speaking, the land-use layout of the surveyed schools falls into three types: ring-shaped with a center, linear, and group-based. Besides, thus, the main factors which exert certain influence on the pattern of spatial layout and the land-use structure of educational space in primary and secondary schools in the downtown area, Tianjin are identified by data analysis. It provides reference for the intensive use of educational space in primary and secondary schools, and lays a solid foundation for formulating a series of land-use planning and management policies targeted at primary and secondary schools.

Selection and Spatial Layout of Urban Sports Facilities Guided by Residents' Demand

In order to explore the theory of the spatial layout of urban sports facilities, starting with the analysis of theoretical knowledge, the current situation of public sports facilities in the central urban area of Jinan is analyzed, the various factors affecting the planning layout are discussed, and the strategies and methods of the layout planning of public sports facilities in Jinan are summarized. The results show that the layout planning of public sports facilities should follow the corresponding patterns and principles. The layout of public sports facilities at all levels should fully consider the factors of urban public transport, urban management system, urban public functions, and reasonable service radius of public sports facilities. It can be seen that excessive pursuit of efficiency will lead to excessive service radius and poor accessibility of urban public sports facilities; excessive pursuit of fairness will result in a small and scattered layout pattern, which easily leads to idle waste.

Transformable Electronics Implantation in ROM for Anti-Reverse Engineering

The protection of intellectual property (IP) is increasingly critical for IP vendors in the semiconductor industry. Read Only Memories (ROMs) serve as important non-volatile memory in various hardware systems to store predefined data and programs, which is critical to IP protection. Its pre-determined layout pattern makes unauthorized data extraction through chip-level reverse engineering easy to carry out. Advanced reverse engineering techniques can physically disassemble the chip and derive the IPs precisely at a much lower cost than the value of IP design that chips carry. This invasive hardware attack obtaining information from IC chips always violates the IP rights of vendors. This paper proposes a new security mechanism implanted ROM design to address the vulnerability to reverse energy attacks. Irreversible via in ROM layout transform triggered by reverse engineering completely changes the electrical properties and the physical structure of ROMs that determine the stored data. Newly-created patten will significantly increase the difficulty of reverse engineering, even lead the attackers to another working function mode. Furthermore, to improve the effectiveness of the proposed technique, a systematic design method is developed targeting integrated circuits with multiple design constraints. Two widely used ROM scheme cases have been studied to test the design method and its effectiveness. Simulations have been conducted to demonstrate the capability of the proposed technique, which generates extremely large complexity for reverse engineering with manageable overhead. CCS Concepts: Security and privacy → Hardware reverse engineering; Hardware → Hard and soft IP

Insights into different etching properties of continuous wave and atomic layer etching processes for SiO2 and Si3N4 films using voxel-slab model

This work describes the modeling of the surface reactions involved in atomic layer etching (ALE) of SiO2 and Si3N4 with a deposition step using C4F8/O2/Ar plasma and an Ar plasma etch step. In the etching step, the surface was assumed to consist of two layers: a C-F polymer layer and a reactive layer. The effects of residual F from the deposition step and F originating from the C-F polymer layer during the etch step and the influences of the O and N outfluxes generated from the reactive layer were considered, in terms of their effects on the etch rates of the SiO2 and Si3N4 films. Using a three-dimensional voxel-slab model that included the surface reactions described above, an analysis was performed based on the differences between the etching properties of continuous wave (CW) etching and ALE in the cases of blanket wafers and self-aligned contact layers from the viewpoints of numerical simulations. As a result of these analyses, it was found that the use of monoenergetic ion energy improves surface layer thickness controllability for both the polymer layer and the reactive layer and that quantitative control of time variations in both the C-F polymer layer thickness and the ion penetration depth is necessary for high selectivity of SiO2 over Si3N4 (SiO2/Si3N4) and for low plasma-induced damage on the Si3N4 film. Furthermore, in the authors’ simulations, a relatively high SiO2 etch rate was obtained for a modified quasi-ALE (43 nm/min) while maintaining high SiO2/Si3N4 selectivity (more than 100) after optimization of the C-F polymer layer thickness, the ion energy, and the ALE cycle time; this represents a solution in terms of the important issue of the very low etch rate of ALE. These simulation results indicate that accurate prediction of the surface reaction, further quantitative control of the plasma parameters, and optimization of the pattern layout design are necessary to realize higher ALE process performance for practical use in mass production.

Optimum Design of Integrated Magnetic Bearing Using Multiple HTS Bulk Units

Magnetic bearings composed of multiple basic cubic superconducting bulks were investigated. This paper aimed to integrate multiple basic cubic bulks with different performance characteristics and to control the magnetic field properties through design of their arrangement. If this magnetic field characteristic can be controlled, then the optimum configuration for a magnetic bearing can be deduced. In this paper, we aimed to control magnetic bearings with a plurality of basic unit cubic bulks and to control variations in the magnetic characteristics of the bearing surfaces via the arrangement design. We performed calculations of the optimum arrangement that minimizes the inclination angle of the rotation axis of the floating rotating body by combining the structural arrangement pattern of the bearing surface. We constructed a model with a three-row, three-column square arrangement and calculated the layout pattern via an optimization calculation. The cubic bulk was then constructed with this arrangement pattern, and the inclination of the axis of rotation of the floating body was measured using a laser sensor and compared with the calculation result. In addition, the distance between the bearing surface and floating body and the levitation force were measured. We confirmed that suppressing the inclination of the rotation angle through the optimum arrangement was highly effective, indicating the feasibility of controlling the levitation force.

Causality and History: Modes of Causal Investigation in Historical Social Sciences

Studies at the confluence of history and social science address issues of causation in three ways: morphological, variable-centered, and genetic. These approaches to causal investigation differ with regard to their modi operandi, the types of patterns they look for, their underlying assumptions and the challenges they face. Morphological inquiries elaborate causal arguments by uncovering patterns in the empirical layout of socio-historical phenomena. To this end, these inquiries draw on descriptive techniques of data formalization. Variable-centered studies engage causal issues by investigating patterns of association among empirical categories under the twofold assumption that these categories a priori have explanatory relevance and each category empirically has the same meaning across cases. Genetic analyses ground their causal claims by identifying patterned processes of emergence or production.