Engineering Commons^™

Enhanced Raman Spectroscopy Analysis For Contamination Detection On Microelectronic Devices Using Gold Nanoclusters Grown By Dc Magnetron Sputtering, Charin Seesomdee, Prompong Pienpinijtham, Pornchai Rakpongsiri, Sukkaneste Tungasmita

Journal of Metals, Materials and Minerals

Surface-enhanced Raman spectroscopy (SERS) is one of the most powerful analytical techniques for the identification of molecules in microelectronics industry for failure analysis protocols.  Surface-enhanced Raman spectroscopy (SERS) is one of the most powerful analytical techniques for the identification of molecules in the microelectronics industry for failure analysis protocols. In this work, dry-processed gold nanoclusters were prepared by magnetron sputtering deposition to promote the enhancement of the Raman signal from selected common polymers found in the hard disk drive as surface contamination. The optimized sputtering conditions were applied for SERS on poly-carbonate (PC), polyethylene terephthalate (PET), polypropylene (PP), and high-density …

Cellulose-Based Fabrics Triboelectric Nanogenerator: Effect Of Fabric Microstructure On Its Electrical Output, Rawiwan Khwanming, Satana Pongampai, Naratip Vittayakorn, Thitirat Charoonsuk

Journal of Metals, Materials and Minerals

At present, fabric-based triboelectric nanogenerator (TENG) has been paid attention and developed for self-power generation systems with wearability for E-textiles, especially cotton. However, there are many commercial cellulose-based fabrics with different fiber characteristics and fabric structures that gain possibility to effect on TENG performance and has been underreported. This work presents the fabrication of the textile TENG by using four types of commercial cellulose-based fabrics as friction layer and compare the electrical output efficiency relating their molecular structure, fabric structure and surface morphology characteristics. As shown by the electrical output, though all fabrics can generate electricity for TENG device, nevertheless, …

Biomass-Based Nitrogen-Doped Carbon/Polyaniline Composite As Electrode Material For Supercapacitor Devices, Krittaprot Thongkam, Nattawut Chaiyut, Manop Panapoy, Bussarin Ksapabutr

Journal of Metals, Materials and Minerals

Nitrogen-doped activated carbon (N-AC) was prepared from water hyacinth stems for loading polyaniline (PANI) by in-situ polymerization to synthesize N-AC/PANI composites for utilization as electrode materials in supercapacitors. Using potassium hydroxide as the activating agent, stems of water hyacinth were carbonized and activated in a single step to produce N-AC powders. Raman, FTIR, SEM, BET, TGA, and XPS techniques were used to characterize the resultant N-AC materials. The findings revealed that the N-AC materials had a porous structure and high specific surface area. Neat PANI was synthesized by varying the reaction time to 8, 16, and 24 h. During the …

Influence Of Water Content On Structural And Electrochromic Properties Of Tio2 Nanotube Prepared By Anodization, Chantana Aiempanakit, Pathomporn Junbang, Watchara Suphap, Kamon Aiempanakit

Journal of Metals, Materials and Minerals

TiO2 nanotubes (TNTs) and bamboo-type TNTs structure films were synthesized via anodization from sputtered titanium (Ti) films on indium tin oxide (ITO) glass. Herein, the anodization process was adjusted electrolyte with different amounts of deionized water and ethylene glycol. The optical and structural properties of all films before and after annealing were investigated, which affected electrochromic application. The increasing deionized water content in electrolytes resulted in an increase in the average diameter and a decrease in the average length of TNTs. Furthermore, the bamboo-type TNTs structure was produced at the deionized water volume condition of 3 vol%. The crystallite size …

Color Shading, Color Fastness, Antibacterial And Ultraviolet Protection Properties Of Silk Fabric Colored By Silver Nanoparticles, Siriwan Kittinaovarat, Pornchiwin Banjong, Pornapa Sujaridworakun

Journal of Metals, Materials and Minerals

This research studied the effects of different factors used in an in-situ method for forming colored silver nanoparticles (AgNP) on the properties of silk fabric; namely color shading, color strength, relative unlevelness index, color fastness to washing, antibacterial and UV shielding properties. In addition, improvement with an acrylic binder on color fastness to washing and antibacterial property after 20 cycles of washing of AgNP-treated silk fabric were also investigated. It was found that the optimum condition for treatment by the in-situ method was 2.0% owf of silver nitrate (AgNO3) solution, AgNO3 to trisodium citrate ratio at 1:3 (%w/w), exhaustion temperature …

Effect Of Trisilanol Isobutyl Polyhedral Oligomeric Silsesquioxane (Tposs) In Recycled Pet (Rpet) And Polypropylene Based Compound: Investigation On Mechanical Properties, Rujira Phumma, Chutima Vanichvattanadecha, Sarute Ummartyotin

Journal of Metals, Materials and Minerals

Recycled polyethylene terephthalate is successfully prepared. This project is involved for “Circular economy” policy. It is successfully prepared into powder form by nano-grinder technique. 10 phr of PP-g-MA and 1 phr to 5 phr of TPOSS are added for compatibilizer and mechanical properties enhancement, respectively. PP-g-MA can form the chemical linkage of the anhydride groups with the polyamide end groups. 20 wt% of recycled polyethylene terephthalate powder and polypropylene based compound is successfully fabricated by melt mixing. Then, it is fabricated by melting spinning technique. Fourier transform infrared presents Si-O-Si linkage in binary blend compound. X-ray diffraction pattern reports that …

Preparation Of Ga2o3-Modified Sulfated Zirconia Mesopore And Its Application On Cellobiose Hydrolysis, Addy Rachmat, Rizki Dwifahmi, Nova Yuliasari, Ady Mara, Desnelli Desnelli

Journal of Metals, Materials and Minerals

Heterogeneous catalyst plays vital role in biomass processing due to slow rate of biological and naturally pathway processes. Solid acid sulfated zirconia (SZ) is a promising catalyst with properties that can be tuned up. Sulfated zirconia was successfully modified by 2%, 5% and 10% (wt.) Ga2O3 (xGa-SZ; x = 2, 5 and 10) via template-assisted sol-gel method. The catalysts were characterized through various method (XRD, SEM-EDS and Gas Sorption analysis) and applied on hydrolysis of cellobiose, a model compound of cellulose. Diffraction pattern showed xGa-SZ formed completely tetragonal phase whereas un-promoted SZ contains mixed phase of monoclinic and tetragonal. Acidity …

The Changes In Microstructural Features And Physical Properties Of Ceramic Matrix Composite Bonding Tools Under Ultrasonic Service, Apirat Theerapapvisetpong, Karn Serivalsatit, Wuttichai Reainthippayasakul, Wantanee Buggakupta

Journal of Metals, Materials and Minerals

Tape automated bonding (TAB) process plays a key role in the production of disk drives, microchips and other microelectronics components. Such tools should sustain their structures and properties throughout ultrasonic operation and are expected to last until reaching the targeted numbers of TAB cycles. This project aims to evaluate the changes in microstructures and physical properties of the bonding tools under ultrasonic service. Three commercial waffle-type tools from different suppliers were focused, namely Tool A, Tool B and Tool C. They provide different levels of bonding efficiency up to 50k cycles under relatively similar ultrasonic practice. Non-destructive and destructive testing …

Synthesis Of Sic Nanowires On Biochar Surfaces By A Simple Direct Method, Wasana Khongwong, Chumphol Busabok, Piyalak Ngernchuklin

Journal of Metals, Materials and Minerals

Demand for air filters is crucially required due to PM 2.5. So, SiC nanowire networks are directly grown on biochar surfaces that serve strength and filtering purposes. The nanowires were prepared by spraying silicon powder on Lesser bulrush and Grey sedge biochars which acted as carbon sources and heating up to 1300℃ to 1500℃ for 1 h in Ar atmosphere. As a result, silicon powder evaporated and diffused on biochar surfaces. Meanwhile, CO vapor was generated from biochar reacted with O2 in the chamber. The evaporated silicon reacted with both C(s) and CO(g) to form cubic SiC nanowires. At the …

Growth Of Proton Conducting Strontium Cerate Composites, C. K. Shilpa, S. V. Jasira, V. P. Veena, K. M. Nissamudeen

Journal of Metals, Materials and Minerals

The increased population and modern way of life have greatly depleted the effectiveness of traditional energy production methods. There is a strong demand for environmentally friendly and renewable alternatives to replace the old systems. Sustainable energy production systems have emerged as a vital replacement for the conventional use of fossil fuels. Among these, solid oxide fuel cells (SOFCs) play a significant role. Recently, researchers have developed electrolyte components for SOFCs using proton-conducting perovskites with excellent conductivity. This critical assessment presents a yearly overview of innovative strategies for utilizing doped strontium cerate perovskites in energy production systems, a novel approach. The …

Review Of Materials, Functional Components, Fabrication Technologies And Assembling Characteristics For Polymer Electrolyte Membrane Fuel Cells (Pemfcs) – An Update, Arun Daya, Arputharaj Samson Nesaraj

Journal of Metals, Materials and Minerals

Fuel cells use electrochemical processes to transform the chemical energy of a fuel into electrical energy, which is a key enabler for the shift to an H2-based economy. Because of their high energy conversion efficiency and low pollution emissions, fuel cells with polymer electrolyte membranes (PEMFCs) are regarded as being in frontline of commercialization for the transportation and automotive industries. However, there are two major hurdles to their future commercialization: cost and durability, which promote basic study and development of their components. In this article, we reviewed the materials, functional components, fabrication technologies and assembling characteristics related to PEMFCs. Platinum's …

Structure And Chemical Durability Improvement Of Alkali Silicate Glass By Zirconium Dioxide And Erbium Oxide Addition, Ativit Denprawat, Kittipong Sinwanasarp, Pinit Kidkhunthod, Nattapol Laorodphan, Worapong Thiemsorn

Journal of Metals, Materials and Minerals

Glass structure tailoring of alkali silicate glasses by addition of ZrO2 and Er2O3 is found to enhance the chemical durability of glasses. ZrO2 (x ranged between 5 mol% to 15 mol%) and Er2O3 (y ranged between 0.5 mol% to 1.5 mol%) were used to replace SiO2 and Na2O, respectively, in the glasses with the nominal composition of 10Li2O-(15-y)Na2O-10CaO-(65-x)SiO2-xZrO2-y Er2O3. The samples were prepared by conventional melt quenching technique. The structures of produced glasses were examined by X-ray absorption spectroscopy (XAS) and Raman spectroscopy. XAS spectra demonstrated that the oxidation numbers of Zr and Er ions were +4 and +3, respectively. …

Quantum-Based First-Principles Study Of Gas Molecules (O2 , Co2 , No2 ) Interaction On Monolayer Germanene, Arief Hermanto, Harmon Prayogi, Ari Dwi Nugraheni, Juliasih Partini, Sholihun Sholihun

Journal of Metals, Materials and Minerals

We perform calculations of the adsorption energy of O2, CO2, and NO2 molecules on germanene by using the density functional theory (DFT). We find two favorable configurations for O2, the U-site and V-site configurations with similar adsorption energies of -4.10 and -4.32 eV. As for NO2, we find two favorable configurations, the T-site and DB-site configurations. The T-site configuration is 0.98 eV more stable than the IB-site one, and both configurations are chemically adsorbed by germanene. On the contrary for CO2, we find a T-site configuration with adsorption energy of 0.42 eV and the configuration physically adsorbed by germanene.

Synthesis And Modification Of Nickel Hydroxide Particle Synthesized By Self-Assembly And Electron Beam Irradiation Technique For Photocatalyst Activity, Narisara Saechin, Sumitra Sripho, Thitirat Rattanawongwiboon, Sakchai Laksee, Pattra Lertsarawut, Wilasinee Kingkam, Sarute Ummartyotin

Journal of Metals, Materials and Minerals

The purpose of this work is to study the methyl orange removal of Ni(OH)2 nanoparticles. The photo-catalyst activity is investigated based on UV lamp of 18 watt. Ni(OH)2 is synthesized by a self-assembly process and then exposed to electron beam radiation at 10 MeV energy with various doses ranging from 50 kGy to 500 kGy. The properties of Ni(OH)2 nanoparticles are then evaluated. No significant change of functional group and percent of crystallinity are observed. The morphology is uniformly presented as a plate-like. The specific surface area, pore size and pore volume are reduced. Point of zero charge confirmed that …

Effect Of Calcination Frequency On The Thermoelectric Properties Of Ti Doped Cucro By Solid State Method, Doli Bonardo, Nono Darsono, Syahrul Humaidi, Agung Imaduddin, Noni Surtiana Silalahi

Journal of Metals, Materials and Minerals

In this study, the influence of titanium oxide (TiO2) dopants and varying calcination processes on the thermoelectric properties of CuCrO2 was systematically explored. It was emphasized that these factors were not only affecting dislocation density but also exerting a profound influence on thermoelectric performance through the modulation of Seebeck coefficient and resistivity. The findings highlighted CrT-2, which incorporated TiO2 and underwent a two-time calcination process, as the top-performing sample in terms of power factor values, underscoring the significance of TiO2 as a dopant for enhancing thermoelectric efficiency. Conversely, Cr-4, exposed to four calcination cycles, exhibited slightly lower power factor values …

Electrical And Water Resistance Properties Of Conductive Paste Based On Gold/Silver Composites, Sutthipoj Wongrerkdee, Supab Choopun, Pichitchai Pimpang

Journal of Metals, Materials and Minerals

This study aimed to investigate the effects of a corrosive environment on both the electrical and the water resistance properties of conductive paste based on gold/silver composites. The conductive paste was prepared by incorporating silver and gold powders, polyvinyl acetate, polyvinyl chloride as adhesive components, and methyl isobutyl ketone as a diluent. The gold/silver composite powder was prepared with different mass ratios of gold and silver. The paste was coated on a substrate and heated at 80℃ to form the conductive paste film. Characterizations of conductive paste were performed by using FT-IR spectroscopy, electrometry, cyclic voltammetry, and contact angle measurements. …

Molybdenum Disulfide-Zirconium Dioxide Composite With Enhance Supercapacitance Performance, Razan Nadhim Shaker, Sami Mohammed, Yousra Ali Abdulsayed

Journal of Metals, Materials and Minerals

As a supercapacitor active material, molybdenum disulfide (MoS2) layer offers good conductivity, large surface area, and electrochemical stability. In practice, however, its capacitance is low in comparison to other materials. This work synthesized MoS2-zirconium dioxide (ZrO2) composite in a simple, high-throughput way to test it as a supercapacitor active layer. During the tests, the composite shows a gravimetric capacitance of 500.0 F⸳g-1, while MoS2 and ZrO2 have capacitances of 265.12 and 152.43, respectively. The increase in capacitance of composite stems from the synergistic effect between ZrO2's pseudocapacitor behavior and MoS2's electric double layer capacitance (EDLC). Moreover, the composite has a …

Photocatalytic Reforming Of Lignocellulose: A Review, Xinyuan Xu, Lei Shi, Shu Zhang, Zhimin Ao, Jinqiang Zhang, Shaobin Wang, Hongqi Sun

Research outputs 2022 to 2026

Biomass has been considered as a promising energy resource to combat the exhaustion of fossil fuels, as it is renewable, sustainable, and clean. Photocatalytic reforming is a novel technology to utilize solar energy for upgrading biomass in relatively mild conditions. This process efficiently reforms and recasts biomass into hydrogen and/or valuable chemicals. To date, lignocellulose, including cellulose, hemicellulose and lignin, has attracted extensive studies in facile photocatalytic valorisation. This review summarizes and analyzes the most recent research advances on photoreforming of lignocellulose to provide insights for future research, with a particular emphasis on the reformation of lignin because of its …

A Bibliometric Analysis And Review On The Performance Of Polymer-Modified Bitumen, Adham M. Alnadish, Herda Y. B. Katman, Mohd R. Ibrahim, Yaser Gamil, Nuha S. Mashaan

Research outputs 2022 to 2026

The addition of polymer to a base binder has been documented as a successful approach in terms of improving physical and rheological properties of the base bitumen. However, the main drawbacks of polymer-modified bitumen are incompatibility and degradation of polymer due to aging. This article aims to introduce a bibliometric analysis and review on modifying bitumen with polymers. Additionally, this article intent to highlight the significant gaps and recommendations for future work. Furthermore, another objective of this article is to provide a worth attempt regrading reducing the negative impact of polymer’s drawbacks on the performance of polymer-modified base binder. The …

Corrosion Behavior And Mechanisms Of The Heat-Treated Ti5cu Produced By Laser Powder Bed Fusion, Xin Wang, Peng Qin, L. Y. Chen, Hongqi Sun, Laichang Zhang

Research outputs 2022 to 2026

This work investigated the corrosion behavior of laser powder bed fusion produced (LPBFed) Ti5Cu and its heat-treated counterparts at 740 and 900 °C (named as HT-740 and HT-900 respectively) in Hank’s solution. The results indicated that the presence of acicular a'-Ti phase in LPBFed Ti5Cu was beneficial to corrosion, but the corrosion resistance of HT-740 and HT-900 were increased owing to the dual-phase microstructure (a'/a-Ti + Ti2Cu) or the increased content of Ti2Cu phase in the microstructure. The Ti2Cu phase could provide an ‘envelope’ protection to the a'/a-Ti phase and slow down the micro-galvanic reaction between a'/a-Ti phase and Ti2Cu …

Instantaneous Frequency Estimation Of Fm Signals Under Gaussian And Symmetric Alpha-Stable Noise: Deep Learning Versus Time-Frequency Analysis, Huda Saleem Razzaq, Zahir M. Hussain

Research outputs 2022 to 2026

Deep learning (DL) and machine learning (ML) are widely used in many fields but rarely used in the frequency estimation (FE) and slope estimation (SE) of signals. Frequency and slope estimation for frequency-modulated (FM) and single-tone sinusoidal signals are essential in various applications, such as wireless communications, sound navigation and ranging (SONAR), and radio detection and ranging (RADAR) measurements. This work proposed a novel frequency estimation technique for instantaneous linear FM (LFM) sinusoidal wave using deep learning. Deep neural networks (DNN) and convolutional neural networks (CNN) are classes of artificial neural networks (ANNs) used for the frequency and slope estimation …

Driving Training-Based Optimization (Dtbo) For Global Maximum Power Point Tracking For A Photovoltaic System Under Partial Shading Condition, Haroon Rehman, Injila Sajid, Adil Sarwar, Mohd Tariq, Farhad I. Bakhsh, Shafiq Ahmad, Haitham A. Mahmoud, Asma Aziz

Research outputs 2022 to 2026

The presence of bypass diodes in photovoltaic (PV) arrays can mitigate the negative effects of partial shading conditions (PSCs), which can cause multiple peak characteristics at the output. However, conventional maximum power point tracking (MPPT) methods can develop errors and detect the local maximum power point (LMPP) instead of the global maximum power point (GMPP) under certain circumstances. To address this issue, several artificial intelligence (AI)-based methods have been proposed, but they result in complicated and unreliable methodologies. This study introduces the driving training-based optimization (DTBO) method, which aims to address the partial shading (PS) problem quickly and reliably in …

Applying Machine Learning To Biological Status (Qvalues) From Physio-Chemical Conditions Of Irish Rivers, Raúl Martín Sánchez

ICT

This thesis evaluates and optimises a variety of predictive models for assessing biological classification status, with an emphasis on water quality monitoring. Grounded in previous pertinent studies, it builds on the findings of (Arrighi and Castelli, 2023) concerning Tuscany’s river catchments, highlighting a solid correlation between river ecological status and parameters like summer climate and land use. They achieved an 80% prediction precision using the Random Forest algorithm, particularly adept at identifying "good" ecological conditions, leveraging a dataset devoid of chemical data.

Recurrent Neural Networks For Flash Gdp Estimates In Ireland: A Comparison With Traditional Econometric Methods, Justin Flannery

ICT

GDP is the single most important barometer for the health of an economy. It’s an important input into the decision making processes of government, industry and state institutions such as central banks. To be useful as an indicator, GDP estimates need to be both timely and accurate. To meet the needs of users, many national statistical institutes publish early or flash estimates of GDP which are produced within 30 days after the end of a quarter. Given the long lags involved in the data collection processes which feed into GDP estimates, these flash estimates are often largely model based. Within …

Unlocking The Pragmatics Of Emoji: Evaluation Of The Integration Of Pragmatic Markers For Sarcasm Detection, Niamh Farnham

ICT

Emojis have become an integral element of online communications, serving as a powerful, under-utilised resource for enhancing pragmatic understanding in NLP. Previous works have highlighted their potential for improvement of more complex tasks such as the identification of figurative literary devices including sarcasm due to their role in conveying tone within text. However present state-of-the-art does not include the consideration of emoji or adequately address sarcastic markers such as sentiment incongruence. This work aims to integrate these concepts to generate more robust solutions for sarcasm detection leveraging enhanced pragmatic features from both emoji and text tokens. This was achieved by …

Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer

Cal Poly Humboldt theses and projects

A growing interest in sustainable waste management and the implementation of new policies have prompted a shift towards alternative resource recovery methods for organic waste, including food waste. To effectively assess alternative food waste treatment scenarios, it is important to evaluate the life cycle impacts associated with each scenario. The storage phase of food waste, encompassing its accumulation in kitchens, and storage in bins for collection and transportation, has been overlooked as a source of greenhouse gases in previous studies. This investigation aimed to identify the greenhouse gases emitted during the initial five-day period of low-oxygen storage. An open dynamic …

Patient-Specific Analysis Of Aortic Hemodynamics And Wall Shear Stresses In Patients Undergoing Pediatric Bariatric Surgery Using 2d Phase-Contrast Mri, Oluwaferanmi S. Akande, Joao Soares, Nathan Hargan, Dr. Uyen Truong, Haeung Kang, David Lanning

Undergraduate Research Posters

Patient-Specific Analysis of Aortic Hemodynamics and Wall Shear Stresses in Patients Undergoing Pediatric Bariatric Surgery using 2D Phase-Contrast MRI

Feranmi Akande¹ Nathan Hargan² Haesung Kang³ David Lanning³ Uyen Truong⁴ João S. Soares¹

¹ Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University

² Department of Mechanical & Nuclear Engineering, College of Engineering, Virginia Commonwealth University

³ Department of Cardiology, Children’s Hospital of Richmond, Virginia Commonwealth University

Introduction: Severe obesity among today’s youth is a rising epidemic within the United States. Emerging research has linked childhood obesity with shortened life expectancy and early …

Finite Element Analysis Of 3d-Printed Pcl Scaffolds, Ireolu K. Orenuga, Joao Soares, Phillip D. Glass, Daeha Joung Ph.D.

Undergraduate Research Posters

Finite Element Analysis of 3D-printed PCL Scaffolds for Synergizing Cellular Micro-Environment and Mechanical Stimuli to Enhance Engineered Tissue Growth in Vitro

Ireolu Orenuga,1 Phillip Glass,2 Daeha Joung,2 Joao S. Soares1

1. Department of Mechanical and Nuclear Engineering, College of Engineering, Virginia Commonwealth University
2. Department of Physics, College of Humanities & Sciences, Virginia Commonwealth University

Introduction: Tissue engineering aims to create viable and functional engineered tissues via biodegradable scaffolds and autologous cells. Scaffolds play an essential part in organizing the architecture of developing tissues and aid in the proper function of implants acutely by serving as mechanical support and long-term by …

Carrier Transport Engineering In Wide Bandgap Semiconductors For Photonic And Memory Device Applications, Ravi Teja Velpula

Dissertations

Wide bandgap (WBG) semiconductors play a crucial role in the current solid-state lighting technology. The AlGaN compound semiconductor is widely used for ultraviolet (UV) light-emitting diodes (LEDs), however, the efficiency of these LEDs is largely in a single-digit percentage range due to several factors. Until recently, AlInN alloy has been relatively unexplored, though it holds potential for light-emitters operating in the visible and UV regions. In this dissertation, the first axial AlInN core-shell nanowire UV LEDs operating in the UV-A and UV-B regions with an internal quantum efficiency (IQE) of 52% are demonstrated. Moreover, the light extraction efficiency of this …

Improving The Stimulation Selectivity In The Human Cochlea By Strategic Selection Of The Current Return Electrode, Ozan Cakmak

Dissertations

The hearing quality provided by cochlear implants are poorly predicted by computer simulations. A realistic cochlear anatomy is crucial for the accuracy of predictions. In this study, the standard multipolar stimulation paradigms are revisited and Rattay’s Activating Function is evaluated in a finite element model of a realistic cochlear geometry that is based on µ-CT images and a commercial lead. The stimulation thresholds across the cochlear fibers were investigated for monopolar, bipolar, tripolar, and a novel (distant) bipolar electrode configuration using an active compartmental nerve model based on Schwartz-Eikhof-Frijns membrane dynamics. The results suggest that skipping of the stimulation point …