bluuebunny/crossref_metadata_2025 huggingface dataset:
Practical Align Overview of the Main Frameworks Used by the Companies to Prevent Cyber Incidents
Authors: Iwashita Rogério Yukio , Junior Luiz Camolesi
Published: September 2020

Among the biggest cybercrime or information security challenges, the information security professionals must be up to date with the new risks, cases, and different ways of attacks. Being up to date in this complex and aggressive scenario is a huge challenge and is a necessity to the security professional to fight against the cybercriminals. Additionally, based on this standard of requisites to start an information security program, an immature professional may be confused on the different frameworks used by the industries, mainly ISO/IEC 27000 family, NIST 800-53, NIST Cybersecurity Framework, COBIT, etc. This chapter will help the information security professional to decide where is important to focus efforts, to decide what is feasible and which control does not demand any additional investment. Additionally, this grade helps the InfoSec professionals to compare the information security maturity level within the companies and between the companies, comparing with benchmarks.
Prediction, Detection, and Mitigation of DDoS Attacks Using HPCs
Authors: Do Nascimento Pablo Pessoa , Colares Isac F. A. F. , Maciel Ronierison , Da Silva Humberto Caetano , Maciel Paulo
Published: September 2020

Web service interruptions caused by DDoS (distributed denial of service) attacks have increased considerably over the years, and intrusion detection systems (IDS) are not enough to detect threats on the network, even when used together with intrusion prevention systems (IPS), taking into account the increase of assets in the traffic path, where it creates unique points of failure in the system, and also taking into account the use of data that contains information about normal traffic situations and attacks, where this comparison and analysis can cost a significant amount of host resources, to try to guarantee the prediction, detection, and mitigation of attacks in real-time or in time between detection and mitigation, being crucial in harm reduction. This chapter presents an adaptive architecture that combines techniques, methods, and tools from different segments to improve detection accuracy as well as the prediction and mitigation of these threats and to show that it is capable of implementing a powerful architecture against this type of threat, DDoS attacks.
Self-Driving Robotic Cars
Authors: Pisarov Jelena L. , Mester Gyula
Published: September 2020

Even the behavior of a single driver can have a dramatic impact on hundreds of cars, making it more difficult to manage traffic. While the attempts to analyze and correct the traffic patterns that lead to congestion began as early in the 1930s, it wasn't until recently that scientists developed simulation techniques and advanced algorithms to create more realistic visualizations of traffic flow. In experiments conducted by Alexandre Bayen and the Liao-Cho, which included several dozen cars in a small-scale closed circuit, a single autonomous vehicle could eliminate traffic jams by moderating the speed of every car on the road. In larger simulations, the research showed that once their number rises to 5-10% of all cars in the traffic, they can manage localized traffic even in complex environments, such as merging multiple lanes of traffic into two or navigating extremely busy sections.
Statistical Methods for Conducting the Ontology and Classifications of Fake News on Social Media
Authors: Nehinbe Joshua Ojo
Published: September 2020

Fake news and its impacts are serious threats to social media in recent time. Studies on the ontology of these problems reveal that serious cybercrimes such as character assassination, misinformation, and blackmailing that some people intentionally perpetrate through social networks significantly correlate with fake news. Consequently, some classical studies on social anthropology have profiled the problems and motives of perpetrators of fake news on political, rivalry, and religious issues in contemporary society. However, this classification is restrictive and statistically defective in dealing with cyber security, forensic problems, and investigation of social dynamics on social media. This chapter exhaustively discusses the above issues and identifies solutions to challenges confronting research community in the above domain. Thematic analysis of responses of certain respondents reveal three new classifications of fake news that people propagate on social media on the basis of mode of propagation, motives of perpetrators, and impacts on victims.
MRF Model-Based Estimation of Camera Parameters and Detection of Underwater Moving Objects
Authors: Panda Susmita , Nanda Pradipta Kumar
Published: September 2020

The detection of underwater objects in a video is a challenging problem particularly when both the camera and the objects are in motion. In this article, this problem has been conceived as an incomplete data problem and hence the problem is formulated in expectation maximization (EM) framework. In the E-step, the frame labels are the maximum a posterior (MAP) estimates, which are obtained using simulated annealing (SA) and the iterated conditional mode (ICM) algorithm. In the M-step, the camera model parameters, both intrinsic and extrinsic, are estimated. In case of parameter estimation, the features are extracted at coarse and fine scale. In order to continuously detect the object in different video frames, EM algorithm is repeated for each frame. The performance of the proposed scheme has been compared with other algorithms and the proposed algorithm is found to outperform.
Implementation and Evaluation of Local Knowledge Inheritance System
Authors: Ishida Tomoyuki , Ito Hayato
Published: September 2020

In this study, we implemented and evaluated a local knowledge inheritance system using old maps and location-based augmented reality (AR) technology. This system is comprised of a mobile local knowledge inheritance application and a local knowledge inheritance data management system. This system provides local knowledge to users using a map axis and location-based AR on mobile terminals. The map axis clarifies the relevance associated with the times and themes in local knowledge. We conducted an evaluation experiment with 47 local residents. The results confirm the effectiveness of the system relative to improving understanding of local knowledge and the effectiveness of using museum materials.
A Survey of Municipal Open Data Repositories in the U.S.
Authors: Wilson Bev , Cong Cong
Published: September 2020

Cities in the United States are increasingly embracing open data as a means of advancing a variety of interests. Promoting transparency, facilitating public engagement, proactively managing records requests, and fostering innovation in the public and private sectors are among the commonly cited motivations for this phenomenon. While there is an extensive literature on the benefits and challenges of open government data, there are far fewer empirical studies that explore and document how these initiatives are unfolding at the local government scale. This article asks what kinds of data are being made open in U.S. cities and to what extent do open data policies and related regulatory actions matter in shaping the content and structure of public-facing repositories. The authors conclude that population size and regulatory actions exert a positive influence on the amount and variety of datasets provided through municipal open data portals. Implications for the design and governance of open government data initiatives at the local level are also discussed.
Fog-Assisted Privacy Preservation Scheme for Location-Based Services Based on Trust Relationship
Authors: Manju A. B. , Subramanian Sumathy
Published: September 2020

With advancements in smart mobile devices and their capabilities, location-based services have gained utmost importance, as its individual and social benefits are enormous. Users of location-based services have a concern to the security issues posed by its usage as the location service providers track the users' interests, behavior, and identity information. Most of the location-based services are launched from mobile phones that have stringent resources; hence incorporating encryption schemes becomes tedious, and further, dual identity attacks uncover the encrypted message. A fog-assisted privacy protection scheme for location-based service (FPriLBS) employs a semi-trusted third party as a fog server to eliminate redundant queries submitted to the location service provider in addition to the trusted helper selection scheme which hides the real identity of the user from the fog server. The experimental results show that the proposed FPriLBS outperforms the existing schemes in terms of processing time and processing cost.
Modified Migrating Birds Optimization for Solving the Low-carbon Scheduling Problem
Authors: Zhang Zhifeng , Sun Yusheng , Cui Yadong , Zhu Haodong
Published: September 2020

Production scheduling problems have historically emphasized cycle time without involving the environmental factors. In the study, a low-carbon scheduling problem in a flexible job shop is considered to minimize the energy consumption, which mainly consists of two parts: the useful part and the wasted part. First, a mathematical model is built based on the features of the workshop. Second, a modified migrating bird's optimization (MMBO) is developed to obtain the optimal solution. In the MMBO, a population initialization scheme is designed to enhance the solution quality and convergence speed. Five types of neighborhood structures are introduced to create neighborhood solutions. Furthermore, a local search method and a reset mechanism are developed to improve the computational results. Finally, experimental results validate that the MMBO is effective and feasible.
An Optimized Coverage Robot SLAM Algorithm Based on Improved Particle Filter for WSN Nodes
Authors: Zhang Wei , Yanli Du  , Qinghua Bai
Published: September 2020

In order to realize the positioning and creation of the environment of mobile robots, this article proposes an optimized coverage robot SLAM algorithm based on an improved particle filter for WSN nodes. The algorithm overcomes the disadvantages of the standard particle filter SLAM algorithm in the simultaneous positioning of robot poses and creation of environmental maps. By constructing the sensor node to cover the high coverage of the SLAM positioning information node of the robot, the algorithm can search for the ideal result under the existing information, and the local optimization is performed to obtain the ideal result in another local state. Thus, the global accurate robot SLAM information is finally obtained. Simulation experiments show that the influence of the time delay parameter for simultaneous positioning of the robot SLAM is almost zero at different speeds, which shows the superior positioning stability of the new algorithm.
A Study on the Relationship Between Customer Loyalty and Customer Trust in Online Shopping
Authors: Haque Umama Nasrin , Mazumder Rabin
Published: September 2020

Recently, the online market environment is quite competitive, and the organizations have to make sure to focus on continuously meeting the current and potential needs of the customers. Customer loyalty is primarily achieved by satisfying customer's expectations. In online shopping, since the products are intangible, it is important to build trust among the customers. Organizations need to thoroughly understand the consumer behavior and consumer needs in order to create and implement effective customer retention strategies. This study attempts to study the relationship between customer loyalty and customer trust in online shopping since trust is the glue that holds the customer relationship together in the current competitive market. Data is collected through the structured questionnaire. The results of this study legitimate the idea that trust of the customer acts as a mediating factor which enhances the loyalty of the customer in regard to the further purchase and consumption of the particular product or service in the online environment.
Best Customer Experience in E-Retailing
Authors: Iqbal Tahir
Published: September 2020

The main purpose of the research is to empirically test a model for assessing the association between outcomes as well as antecedents of online customer experience (OCE) in e-commerce websites in the case of KSA. The theoretical implications of customer online shopping behaviour have largely been discussed in the previously conducted studies however less consideration has been provided to the antecedents of e-retailing shopping and its effect on customer online shopping experience pertaining to KSA. The study has incorporated a quantitative method under which the data has been collected through primary sources using the survey. The sample of 150 respondents has been incorporated who provided their responses through a survey questionnaire. The questionnaire consisted of 13 questions and included five-point Likert scale in order to incorporate responses. The technique of analysis incorporated demographic analysis, correlation analysis and SEM model using SPSS and SmartPLS. It was identified that providing efficient online shopping experience through Tele-presence, ease of use and perceived benefit has a significant positive impact on consumer shopping experience pertaining to the shoppers of KSA.
Renewable Energy-Based Economic Load Dispatch Using Two-Step Biogeography-Based Optimization and Butterfly Optimization Algorithm
Authors: Kundu Subham , Roy Provas Kumar , Mandal Barun
Published: September 2020

This article introduces a unified approach to solve economic load dispatch (ELD) problem of an integrated power system that comprise of traditional thermal power units and renewable sources of energy such as wind energy (WE) and solar photovoltaic (PV) sources; employing a two-step optimization method consisting of Biogeography Based Optimization (BBO) and Butterfly Optimization Algorithm (BOA). BOA imitates the mating and food search process of butterflies for solving the problems associated with global optimization. Nonlinear characteristics of thermal generators is considered in the problem. Weibull distribution is used for determining the uncertainness in availability of wind power and Lognormal PDF is employed for calculating the availability of solar power. The efficacy, robustness and supremacy of the two-step BBO-BOA (hBBO-BOA) technique, compared to various other approaches in literature, are demonstrated by the simulation results. The outcome is quite inspiring, indicates that proposed hBBO-BOA is an efficient approach in order to solve different ELD problems.
Optimal Constrained Tuning of PI-Controllers via a New PSO-Based Technique
Authors: Romasevych Yuriy , Loveikin Viatcheslav , Makarets Valeriy
Published: September 2020

A modified method of particle swarm optimization (PSO) has been developed in the article. It is based on a diversity mechanism (DM), which greatly improves optimization method efficiency. In order to show the enhanced PSO modification, a comparative analysis was conducted. It is based on two proposed criteria and time of the algorithms' execution. The modified method was applied to the problem of constrained optimization of PI-controller tuning. A new criterion was developed with pit-in-pit topology, which includes stability requirement, a set of inequalities (constrains), and a set of optimization criteria to minimize. It allows reducing the initial problem to the problem of unconstrained optimization. The efficiency of the approach is confirmed with four problems of PI-controller tuning.
Sensor Localization in Wireless Sensor Networks Using Cultural Algorithm
Authors: Kulkarni Vaishali Raghavendra , Desai Veena
Published: September 2020

Evolutionary computing-based cultural algorithm (CA) has been developed for anchor-assisted, range-based, multi-stage localization of sensor nodes of wireless sensor networks (WSNs). The results of CA-based localization have been compared with those of swarm intelligence-based algorithms, namely the artificial bee colony algorithm and the particle swarm optimization algorithm. The algorithms have been compared in terms of mean localization error and computing time. The simulation results show that the CA performs the localization in a more accurate manner and at a higher speed than the other two algorithms.
Research Progress in Nickel Base Single Crystal Superalloys
Authors: Jiang Zhao Jun , Wang Jun , Cao Dong Mei
Published: September 2020

Nickel base single crystal superalloy is widely used in hot end parts of aeroengine because of its excellent creep, fatigue and oxidation resistance. In the face of strong market demand and the emergence of new technologies and methods, in 2019, nickel-based single crystal superalloys have made remarkable achievements in preparation and heat treatment processes, repair techniques, test methods, characterization methods, theoretical simulation analysis and composition design, which continuously promotes the development of nickel base single crystal superalloy to the direction of high performance and low cost. The present work reviews the progresses from preparation and heat treatment process, repair technology of service alloy structure, service evaluation of alloy, high flux composition design. The progress in the design, preparation and engineering application of superalloy materials will eventually promote the development of a new generation of aeroengine.
Welding Operation Technique of Welding Electrode Arc Welding Overhead Welding Test Board
Authors: Li Xing Hui
Published: September 2020

Welding electrode arc welding, upside welding, single side welding, double side forming welding operation technology is the most difficult welding process in manual arc welding operation. It is an operation technology that senior welding operators must master, and it reflects the technical level of the welding welder. . In this paper, the welding operation essentials and operation skills of backing welding, filling welding and cover welding are studied for the welding operation of the back welding test board, which creates a theoretical basis for the improvement of the welding operator's operation skills.
Interface Optimization of Al2O3-Fe Composite Materials Prepared via Vacuum Sintering Method
Authors: Wang Rui Hua , Chen Ai Xia , Yang Chao , Wang Fang , Xu Ming Han , Li Shi Bin , Song Jie Guang , Chen Lin
Published: September 2020

In this paper, the effect of sintering temperature on the interfacial structure of the composite was investigated and three different formulation groups were used to compare the respective properties. To obtain a composite material with excellent interface, the law between reference number and performance is obtained. Through mixing, molding, sintering, sample preparation, scanning electron microscopic observation, energy spectrometer observation and analysis, the following conclusions can be drawn: As the temperature increases, the density and hardness increase. The sample melts at 1500 °C, and there is no specific data. When the temperature reaches 1450 °C, the density and hardness reach the highest. When the formulation is Fe:Al2O3:SiO2=18:1:1 and the temperature reaches 1450 °C, the properties of the sample materials are optimized. The density is as high as 95% and the hardness reaches 42.9HBW.
Resin Made Long-Period Fiber Grating Structure for Tunable Optical Filter inside Single-Mode Fiber
Authors: Khun-In Ravivudh , Usuda Yuji , Jiraraksopakun Yuttapong , Bhatranand Apichai , Yokoi Hideki
Published: September 2020

The rectangular-structured resin with one of its triangular long-period fiber grating surface is designed and printed out by using a high resolution 3D printer, so called long-period fiber grating (LPFG) resin. This LPFG resin is directly pressed on the bare single-mode fiber by a digital force meter to filter out partial band of light inside the fiber. The grating period is expanded by tilting the resin from the initial fiber axis. The optical filter is observed as resonant wavelengths from the broadband wavelength. The results show that the resonant wavelength shift is a linear function of the grating period with the coefficient of determination over 0.99. The proposed scheme has a great potential to be employed as a sensor such as a selective optical filter and a buried intrusion sensor.
Copper (II) Oxide Powder Prepared by Low Temperature Hydrothermal Method
Authors: Pookmanee Pusit , Mueangjai Maneerat , Phanichphant Sukon , Thanachayanont Chanchana
Published: September 2020

In this research, CuO powder was prepared by low temperature hydrothermal method. Copper (II) nitrate trihydrate (Cu (NO3)2.3H2O) and sodium hydroxide (NaOH) were used as the starting precursors. The final pH value of the mixed solution was adjusted to 9 by 4M NaOH and treated at 100 oC and 200 oC for 4 and 6 h. The black fine powder was obtained after dried at 80 oC for 4 h. The phase was characterized by X-ray diffraction (XRD). A single phase of monoclinic structure of CuO powder prepared by low temperature hydrothermal method at 200 oC for 4 and 6 h was obtained without calcination step. The morphology and particle size were investigated by scanning electron microscopy (SEM). The morphology was flower-like in shape and the average particle size in range of 0.3×0.7 μm. The element composition was indicated by energy dispersive X-ray spectrometry (EDX). The chemical compositions showed the characteristic X-ray energy of copper (Kα = 0.95 keV) and oxygen (Kα = 0.53 keV). The functional group was indentified by fourier transform spectrophotometry (FTIR). The wavenumber at 433-531 cm-1 was corresponded to vibration of Cu-O stretching.
Study of the Manufacturability of Production and Properties of Welding Wire from Alloy 1580
Authors: Sidelnikov Sergey , Baranov Vladimir N. , Dovzhenko Nikolay , Startsev Aleksey , Voroshilov Denis , Lopatina Ekaterina , Orelkina Tamara , Yurev Pavel , Yakivyuk Olga , Galiev Roman
Published: September 2020

The results of studies on the production of welding wires with a diameter of 2.5 and 3.3 mm from alloy 1580 are presented. To compare the manufacturability of the processing, various methods were used to obtain billets for drawing with a diameter of 8-12 mm: the traditional method of direct hot extruding (discrete); combined rolling-extruding method; and ingotless rolling-extruding method (continuous). The developed modes of bar rolling, drawing and annealing made it possible to obtain prototypes of wire in laboratory and industrial conditions. It was found that alloy 1580 is highly manufacturable both with the traditional method of pressure treatment (extruding) and with combined rolling-extruding methods. It was revealed that the application of all methods makes it possible to obtain billets with the level of mechanical properties necessary for further multi-operation processing. Based on the results of research obtained in laboratory conditions, rational drawing modes for industrial wire production have been developed. As a result of bay drawing, pilot batches of welding wire with a diameter of 3.26 and 2.47 mm from alloy 1580 were obtained, which was successfully used for welding sheet metal.
Enhancement of Thermal and Sound Insulation Properties of Cement Composite Roofing Tile by Addition of Nanocellulose Coated Pineapple Fiber and Modified Rubber Tire Waste
Authors: Hancharoen Kanokon , Kamhangrittirong Parames , Suwanna Pimsiree
Published: September 2020

In this work, the enhancement of thermal and sound insulation properties of cement composite roofing tile with nanocellulose coated pineapple fiber and modified waste tire rubber is studied. The composite was composed of bacterial nanocellose (BNC) coated pineapple fibers, modified rubber particles, platicizer and type I Portland cement in the weight ratio of 10:50:0.8:100 with the water to cement ratio (w/c) of 0.5. The thermal conducitity of the fiber rubber cement composite could be reduced to 0.1080 ± 0.0048 W/m.K as opposed to 0.3810 ± 0.0041 and 0.5860 ± 0.0050 W/m.K for the fiber cement and the rubber cement composites, respectively. Moreover, the noise reduction coefficient of the fiber rubber cement composite could be increased to 0.2832 as opposed to 0.2143 and 0.1899 for the fiber cement and the rubber cement composites, respectively. These results revealed that adding nanocellulose coated pineapple fiber and modified rubber particles together to the cement composite can enhance the thermal insulation and sound absorption abilities of the composite roof tile significantly better than adding each constituent separately.
Mechanical Properties and Microstructure of Oil Palm Fiber (OPF) Partial Replacement of Cement
Authors: Vasudevan Gunalaan
Published: September 2020

This research showed the results of experiments effect use of oil palm fibre (OPF) from oil palm industry as partial replacement for ordinary Portland cement. Research on the reuse of waste materials in the concrete industry has been quite intensive in the past decade. The objective of this research is to identify the Effect of oil palm fibre as a partial cement replacement in the production of concrete. After the treatment, the economical ways to dispose of it is by using landfill method. But due to a limited landfill site in Malaysia and it is the temporary solution for the disposal of the waste, it becomes a problem to Malaysia and the number of the oil palm fibre keeping increase year by year because of the population increase year by year too. The results showed that oil palm fibre (OPF) greatly improved the compressive and flexural strength of concrete. The rate of water absorption of oil palm fibre (OPF) concrete was reduced as oil palm fibre filled up the existing voids, making it more impermeable. However, the compressive strength of the oil palm fibre concrete decreases gradually when the amount of oil palm fibre (OPF) increased. It can be concluded that the optimum percentage of oil palm fibre as a partial cement replacement is 10%. In this direction, an experimental investigation of ultrasonic pulse velocity, carbonation test, compressive strength, flexural strength and water absorption was undertaken to use oil palm fiber and admixtures as partial replacement for cement in concrete.
Numerical Analysis of Effect of Different Initial Morphologies on Molten Pool Flows
Authors: Li Kai , Zhao Zhen Yu , Zhou Hou Ming , Zhou Hao , Jin Jing Cheng
Published: September 2020

The different initial morphologies of polished surface is one of the important factors affecting the quality of laser polishing. In order to investigate the flow characteristics of the molten pool with different morphologies, a two-dimensional (2D) axisymmetric numerical model is established based on the COMSOL software. The nonisothermal flow interface is used to couple the heat transfer and fluid flow, and simulate the evolution process of the molten pool with three different surface morphologies. The results show that the initial shape is a smooth plane, the flow velocity of the molten pool is stable and always in thermocapillary regime, then the protrusions were generated at the edge of the molten pool. Likewise, with the increase of the surface curvature, the capillary becomes the main driving force to eliminate the surface asperities. While the flow velocity and instability of the molten pool enhance, and the depth of the molten pool increases with the heat transfer generated by the mass flow along the z-axis direction.
Mode Stresses for the Interaction between Two Inclined Cracks in Bonded Two Half Planes
Authors: Hamzah Khairum Bin , Nik Long Nik Mohd Asri
Published: September 2020

The various mode of stresses for the interaction between two inclined cracks in the upper part of bonded two half planes which are normal stress (Mode I), shear stress (Mode II), tearing stress (Mode III) and mixed stress was studied. For this problem, the modified complex potentials (MCPs) method was used to develop the new system of hypersingular integral equations (HSIEs) by applying the conditions for continuity of resultant force and displacement functions with the unknown variable of crack opening displacement (COD) function and the right hand terms are the tractions along the crack. The curve length coordinate method and Gauss quadrature rules were used to solve numerically the obtained HSIEs to compute the stress intensity factors (SIFs) in order to determine the strength of the materials containing cracks. Numerical solutions presented the characteristic of nondimensional SIFs at the cracks tips. It is obtained that the various stresses and the elastic constants ratio are influences to the value of nondimensional SIFs at the crack tips.
Study on Fatigue Behaviors of 0Cr21Mn17Mo2N0.83 High Nitrogen Stainless Steels
Authors: Yang You , Tang Wei Feng
Published: September 2020

High cycle fatigue behaviors of 0Cr21Mn17Mo2N0.83 high nitrogen stainless steels at forged and solid solution state were investigated. High cycle fatigue tests were carried out up to 107cycles at a stress ratio R=0.1 and frequency of 70Hz on specimens using a high frequency fatigue machine. Fatigue fracture surfaces of specimens that in the high cycle fatigue tests were observed using a scanning electron microscope for revealing the micro-mechanisms of fatigue crack initiation and propagation. The results showed that the fatigue limit of test alloys at room temperature is 865.25 MPa (as-forged alloy) and 736.10MPa (solid solution alloy), respectively. The micro-fatigue fracture surface of the test alloys included three representative regions. These regions are fatigue initiation area, fatigue crack propagation area and fatigue fracture area. Fatigue cracks of the test alloys initiate principally at the precipitates, inclusion or uneven stress concentration sites of alloy surface, and propagate along the grain boundary. The fatigue striations of fatigue crack propagation area are very clear. The fatigue fracture of test specimens show the rupture characteristics of quasi cleavage and dimple fracture. The room temperature fatigue properties of as-forged alloy are generally higher than that of the solid solution high nitrogen stainless steel according to the S-N curves fitting results.
Microstructure and Mechanical Properties of Laser Butt Welded Laser Powder Bed Fusion Manufactured and Sheet Metal 316L Parts
Authors: Rautio Timo , Jalava-Kanervio Juho , Kumpula Jani , Mäkikangas Jarmo , Järvenpää Antti
Published: September 2020

Laser weldability of dissimilar parts produced with different techniques from 316L material was studied in this paper. Butt joint welding was performed on pairs of sheet metal and parts produced with additive manufacturing by laser powder bed fusion. The effect of heat treatment was also considered and the stage in which it was applied. The experiments showed very good weldability and the results were verified with microstructural analysis and tensile testing with digital image correlation equipment. Microstructures of the welds revealed morphology consisting of equiaxed and columnar grains in somewhat random orientation. Tensile tests showed that the 75% higher yield strength of the printed material compared to sheet metal leads to uneven elongation of the dissimilar joint and the part breaks from the sheet metal side. Hardness measurements showed higher values for the printed side (225 HV) compared to sheet metal side (170 HV). All the welded specimens broke outside of the welds showing a good weldability independent of the heat treatment stage.
Assessment of serum Aspergillus galactomannan expression and associated risk factors among patients living with HIV at Ilorin, Nigeria
Authors: Adekola Hafeez Aderinsayo , Agbede Olajide Olubunmi , Abdullahi Idris Nasir , Olayemi Lawal O. , Emeribe Anthony Uchenna , Dangana Amos , Yunusa Thairu
Published: September 2020

Invasive pulmonary aspergillosis still constitutes a diagnostic challenge for clinicians due to its non-specific symptoms. HIV infection represents one of the major risk factors due to the progressive failure of the immune system. In this study, Aspergillus serum galactomannan enzyme linked immunosorbent assay was used for the diagnosis of invasive pulmonary aspergillosis in patients living with HIV/AIDS attending University of Ilorin Teaching Hospital Antiretroviral Therapy Clinic, Nigeria. Blood samples were collected from 97 patients affected by HIV/AIDS. Age range of the study population was between 0 and 79 years. Length of the study: 3 weeks. Three out of the 97 samples were positive for the galactomannan assay with an optical density index of 1.1, 0.9 and 1.1 using the 0.5 cut-off optical density value; the concentration level of galactomannan antigen was therefore 2.20 μg/L, 1 μg/L and 2.19 μg/L, respectively. A prevalence of 3.1 % (3/97) was detected; all positive participants have been on ART for more than 3 years (P<0.0001), and 2 out of the 3 had CD4 count higher than 200 cells/mm3 (P<0.0001). Serum Aspergillus galactomannan assay is less invasive for patients and diagnosis can be made in a relatively shorter time compared to other techniques used in diagnosing invasive pulmonary aspergillosis.
Unusual cause of laryngeal dyspnea and swallowing troubles in a 2-year old child
Authors: Attia Monia , Bouktif Ime , Affes Meriem , Zairi Sarra , Khalfallah Ikbel , Baccouche Ines , Neji Henda , Hantous Saoussen , Ben Miled Khaoula
Published: September 2020

Plexiform neurofibromas are rare benign tumors developed from peripheral nervous system often associated with neurofibromatosis type 1. We report the case of multifocal plexiform neurofibromas in a 2-year-old child with cervical mass obstructing the trachea causing respiratory distress. A cervical ultrasound examination was performed followed by enhanced CT and MRI. Imaging revealed an expansive cervical mass extended from the base of the skull to the mediastinum associated with similar pelvic and sacral foraminal masses. The target like MRI aspect on T2-weighted images was suggestive of the neural origin. Biopsy under ultrasound control confirmed the diagnosis of plexiform neurofibroma.
Unabridged Histoplasmosis Myositis
Authors: Goraya Gurparvesh S. , Sidhu Guneet , Sidhu Updesh , Paul Birinder S. , Paul Gunchan
Published: September 2020

Histoplasmosis occurs predominantly in immunocompromised hosts and typically presents with mild constitutional symptoms, weight loss, weakness, fatigability, hepatosplenomegaly, and lymphadenopathy. The diagnosis is generally delayed and is based upon isolating the organism in blood cultures or by identifying intracellular organisms in tissues. Disseminated Histoplasmosis is well described in HIV patients but Histoplasmosis myositis is a rare manifestation and has not been reported in seronegative patients till date. We here address a case of a pharmacologically immunosuppressed patient with extensive Histoplasmosis myositis invading almost all the skeletal muscles of body (including plantar foot muscles) with no evidence of dissemination to other organ-systems. Clinical examination and investigations co-related with infiltrative muscle disease and skeletal muscle biopsy revealed Histoplasma capsulatum. This patient illustrates a distinctive clinical presentation of fungal infection with subtle constitutional symptoms and isolated muscle weakness which added to the diagnostic challenge. Hence, differential diagnosis of fungal infection must always be considered as a cause of myopathy in any pharmacologically immunosuppressed patient.
One-stage posterior only corpectomy and fusion in the treatment of a unique acute low lumbar L4 burst fracture without neurologic deficit: A case presentation
Authors: Haddadi Kaveh , Hosseini Seyed , Khadem Aliakbar , Hashemian Mohammad
Published: September 2020

L4 and L5 fractures are different from those at the thoracolumbar area. These differences include anatomy, biomechanics, classification, and treatment possibilities. Given the accessible literature and lack of high-quality information about the management of low lumbar fractures, we describe the case of a young 26-year-old male was referred to our emergency medical center with a severe L4 vertebral body comminuted burst fracture with complete spinal canal compression (AO type 4). Incredible, all neurological functions were intact initially. The patient was cured through a one-stage posterior only vertebrectomy and fusion with preservation of all neurological functions. Clinical and radiologic follow-up was satisfactory after 2 years. In more severe lumbar injuries, decisions contain spinal decompression and stabilization through a posterior or anterior approach based on the surgeon's favorite. In our experience in this patient, a posterior approach only was used both for decompression and stabilization without routine challenging existing in anterior approaches.
Tenecteplase-induced nonaneurysmal subarachnoid hemorrhage in a patient with acute ischemic stroke: A case report and literature review
Authors: Das Biplab , Mahajan Anshu , Goel Gaurav , Garg Arun
Published: September 2020

Recently, tenecteplase (TNK) has been used for intravenous thrombolysis in acute ischemic stroke (AIS). Although spontaneous subarachnoid hemorrhage (SAH) following thrombolysis with tissue plasminogen activator has been reported, there is a lack of literature regarding TNK-induced nonaneurysmal spontaneous SAH. Our index case received intravenous TNK within an hour of symptom onset of AIS. Following deterioration of sensorium, repeat noncontrast computed tomography was performed, which showed diffuse SAH. Cerebral angiography did not reveal any aneurysm. Nonaneurysmal SAH can be a complication of TNK thrombolysis, which is not reported in literature. Knowledge of this possible adverse reaction is critical for appropriate counseling and management.
Parent vessel occlusion via the balloon-assisted, dual microcatheter technique
Authors: Glauser Gregory , Walcott Brian , Choudhri Omar
Published: September 2020

Endovascular parent vessel sacrifice is an established technique used to treat vascular pathology and tumor infiltration of blood vessels. In high-flow vessels, such as the carotid artery or vertebral artery, distal coil migration and embolization are concerns. A method to mitigate this risk would improve the safety profile of the procedure. Five patients undergoing parent vessel sacrifice were retrospectively identified (from June 2018 to May 2019) for the purpose of illustrating this high-flow parent vessel occlusion technique. The technique utilizes a proximal dual-lumen balloon microcatheter inflated for blood flow arrest. The balloon-assisted, dual microcatheter technique is useful for occlusion of high-flow parent arteries. Because it utilizes both flow arrest and a tethered coil backstop, precise occlusion of a vessel can be achieved.
Spinal epidural abscess post spinal anesthesia: An uncommon complication of a common procedure
Authors: Mallik Jeevesh , Motiani Vanita , Pai Manish
Published: September 2020

Spinal epidural abscess (SEA) is a severe pyogenic infection of the epidural space. Bacteria gain access to the epidural space either by hematogenous spread, contiguous spread from a neighboring infected structure, or through iatrogenic inoculation. The diagnosis of SEA is a challenge, largely because of its rarity. We present here a case of SEA of iatrogenic origin (post spinal anesthesia), which we treated at Tata Main Hospital, Jamshedpur.
Subdural empyema complicating a giant fronto-ethmoidal osteoma
Authors: Benzagmout Mohammed , Lakhdar Fayçal , Chakour Khalid , Chaoui Mohammed
Published: September 2020

Osteomas of the paranasal sinuses rarely lead to intracranial manifestations. We present an unusual case of a giant frontal sinus osteoma leading to subdural empyema formation. Determine the origin and the optimal surgical approach of these unusual lesions by analyzing giant osteomas of the frontal and ethmoidal sinuses in the literature. We report a rare case of giant frontoethmoidal osteoma with intracranial extension in a 34-year-old man, revealed by seizures. Neuroradiological studies revealed frontoparietal subdural empyema associated to a large osteoma in the right frontal sinus. The patient underwent surgical evacuation of the empyema and resection of the osteoma in one stage operation of decompressive craniotomy. The patient recovered very well after surgery and postoperative antibiotic therapy. This case represents in the literature only the third-reported case of subdural empyema complicating frontoethmoidal osteoma. The surgical treatment options, including open surgery techniques and endoscopic approaches, as well as pathogenesis are discussed according to the relevant literature.
Fate of patients with chronic cerebrovascular steno-occlusive disease according to change of cerebral perfusion, cerebrovascular reserved, and incidence of recurrent ischemic stroke
Authors: Songsaeng Dittapong , Sriyapai Athaporn , Sakarunchai Ittichai , Yokubol Bencharatana , Nanta-aree Sarun , Tisavipat Nanthasak
Published: September 2020

Objective: The objective is to demonstrate change of cerebral perfusion and cerebrovascular reserve (CVR) in treating patients with cerebrovascular steno-occlusive disease stratified by change of cerebral perfusion and CVR. Methods: Retrospective review patients with radiographic proven major cerebrovascular steno-occlusive disease whom underwent cerebral perfusion imaging with vasoactive stimuli stress test in Siriraj Hospital and Bangkok General Hospital during 2010–2018. Medical records were also reviewed. Radiographic findings, cerebral perfusion parameters and signal change during the stress test were reviewed and used to categorize into three groups. Results: There were 40 patients sent to radiology department for the evaluation of CVR. One patient had airway problem during the procedure and was excluded. Remaining 39 patients were included in this study (32 males and 7 females, mean age of 54.55 years). In 42 sites involved, 28 (66%) were internal carotid artery, 14 (33%) were middle cerebral arteries. Laterality is left side in 20 cases, right side in 14 cases, and bilateral in 5 cases. Poor CVR response (increased cerebral blood flow <10%) was found in 9 patients (2 severe stenoses and 7 total occlusions). The mean follow-up time was 28.9 months. Eight cases (20.5%) underwent surgical treatment; surgical bypasses and endovascular interventions. Only one patient had subsequential ischemic symptom at immediate postoperative vascular bypass surgery. The remaining patients had no report of progressive or recurrent neurological deficit symptom. Conclusion: Poor CVR response is more often found in higher degree of steno-occlusion. Even inconclusive predicting incidence of recurrent ischemic stroke, CVR that reflects the capacity of neuro-autoregulation.
A cavernous venous malformation of the orbit mimicking an idiopathic orbital inflammation
Authors: Chirapapaisan Niphon , Ngamsombat Chanon , Tanboon Jantima , Cheunsuchon Pornsuk , Koohasawad Sugamon
Published: September 2020

Orbital cavernous venous malformations (CVMs) are usually slow progressing. Multiple CVMs, bilateral orbital CVMs, and acute presentations are rare. We present a rare, bilateral, orbital CVM with acute painful visual loss in the left eye. The initial clinical presentation mimicked an idiopathic orbital inflammation. Orbital magnetic resonance imaging revealed its rare location at the left orbital apex. Finally, pathology confirmed the presence of an intralesional hemorrhage of a CVM.
Minimally invasive anterolateral approach for C2 neurofibroma in elderly patient
Authors: Sharma Raghavendra , Yamada Yashuhiro , Tanaka Riki , Sharma Saurabh , Miyatani Kyosuke , Higashiguchi Saeko , Kawase Tsukasa , Talluri Srikanth , Kato Yoko
Published: September 2020

Conventionally ventrally located spinal tumor is approached through anterior vertebrectomy which requires bony fixation and then immobilization for a couple of months. The alternative route to deal with such type of tumor is anterolaterally to avoid the surgical and nonsurgical complications. We are reporting a minimally invasive anterolateral approach for C2 neurofibroma in an 84-year-old patient. Postoperatively this patient did not require cervical brace and postoperative discomfort was minimal. It was observed that dumbbell-shaped cervical tumor with no intradural pathology and wide neural foramina could also be taken care through the anterolateral route which did not require bony fusion or immobilization, but the expertise of the surgeon is necessary for performing these types of minimally invasive procedure to achieve the best results.
Suprasellar tension pneumatocele after endoscopic transsphenoidal surgery for pituitary macroadenoma
Authors: Sharma Anil , Mehta Rupa , Chandrakar Naman , Singh Nikhil , Nagarkar Nitin
Published: September 2020

Tension pneumatocele is a very rare but potentially fatal complication of transsphenoidal surgery that can result from an influx of air into the intracranial cavity through the cerebrospinal fluid fistula. Although transsphenoidal surgeries for pituitary adenomas are very commonly performed procedures, this complication is extremely rare. We report a case of tension pneumatocele after transsphenoidal resection of a pituitary macroadenoma. After a second endoscopic transsphenoidal procedure to remove the air and repair of the sella floor, visual acuity recovered dramatically. Tension pneumatocele is an uncommon but potentially lethal complication of transsphenoidal pituitary surgery, which can present anytime, even after years postoperatively. It is important for all skull base surgeons to be aware of this condition so that prompt treatment can be instituted.
Unusually located proximal middle cerebral artery saccular aneurysm
Authors: Sharma Raghavendra , Yamada Yashuhiro , Tanaka Riki , Sharma Saurabh , Miyatani Kyosuke , Higashiguchi Saeko , Kawase Tsukasa , Talluri Srikanth , Kato Yoko
Published: September 2020

Middle cerebral aneurysms constitute almost one-third of all anterior circulation aneurysms. Most of the saccular aneurysms originate from the arterial branching sites, but origins other than at the branching site are extremely rare. In this article, we are describing a unique M1 segment middle cerebral artery aneurysm which is not related with any branching site. Our literature search suggests that atherosclerotic changes in the arterial wall and local hemodynamic forces play an important role in the development of these types of aneurysm. Surgical management is not so unique in this type of aneurysm, but due to atherosclerotic parent arterial wall and thin-walled aneurysm sac, a neurosurgeon should be more cautious.
A practice survey to compare and identify the usefulness of neuroendoscope and exoscope in the current neurosurgery practice
Authors: Panchal Sunil , Yamada Yasuhiro , Nagatani Tetsuya , Watanabe Tadashi , Kishida Yugo , Sayah Ahmed , Kato Yoko
Published: September 2020

Background: The present era is of new tools and technique. Handling of new challenges require, better understanding of microscopic anatomy, which requires better magnification and light. Microscope has played significant role in this, use of endoscope and introduction of exoscope have given new dimensions to this field. Aim: This study aims to compare and see the advantages, disadvantages of endoscope with exoscope, will analyze the difference in terms of ergonomics, learning curve, opportunities for training, operating time, magnification, and image quality. Materials and Methods: This study was conducted in the Department of Neurosurgery, Bantane Hospital Fujita Health University, Japan. Apart from comparing the specifications of available systems, we conducted a worldwide survey of the two systems through sending questionnaire through mail collected responses and analyzed them. Results: Learning curve, magnification, image quality, and ergonomics favors exoscope but depth perception and maneuverability, hand eye coordination, tactile sensation, and usage of different angulation tubes favored endoscope to be superior to exoscope. Conclusion: There is more scope for modifications and research in both the instruments. These instruments are not replacement of either and should be used according to their indications.