W. Warsito

C-Tech Labs Edwar Technology, Indonesia · Center for Medical Physics and Cancer Research

Skin layer assessment is essential for diagnosing skin conditions or monitoring the effectiveness of treatments. To date, skin layer assessment has been extensively studied based on electrical impedance spectroscopy (EIS) as an alternative and adjuvant tools in noninvasively and portable way. The performance and functionality of EIS to assess the s...

Fast-growing teak is widely cultivated in Indonesia to address the supply and demand of teak trees. However, efforts still need to be made to evaluate the condition of standing teak trees during their growth period. Studies on nondestructive testing (NDT) of wood based on electrical properties through dielectric spectroscopy (DS) are recently being...

Background: There were an estimated 2.1 million breast cancer diagnoses in 2018 worldwide, which is about 11.6% of the total cancer incidence. A novel modality of cancer treatment based on exposure to non-contact electric fields has been developed to reduce cancer incidence. However, the safety of the electric field exposure was not fully investiga...

Electrical capacitance volume tomography measured the gas holdup in two-phase column flotation. The purpose was to characterize gas holdup and understand its relation to flow patterns as a function of the types and doses of frothers. Experiments were conducted using laboratory-scale column flotation cells with dimensions of 5 ×125 cm. The superfici...

Background: A novel modality of cancer treatment based on exposure to non-contact electric fields has been developed to reduce the cancer incidence. However, the safety of this electric field exposure on vital organs has not been fully investigated. Therefore, the purpose of this study was to observe the safety of the electric field exposure on kid...

Osteosarcoma is a highly malignant primary tumor on bone that mainly attacks children and young adolescents. Until now, osteosarcoma therapy still combines some high costs and invasive therapy modalities that may give side effects, such as pain and nausea. Our previous studies suggested that non-contact electric field has anti-proliferative effect...

Background: There were an estimated 2.1 million breast cancer diagnoses in 2018 worldwide, which is about 11.6% of the total cancer incidence. A novel modality of cancer treatment based on exposure to non-contact electric fields has been developed to reduce cancer incidence. However, the safety of the electric field exposure was not fully investiga...

Intermediate frequency and low intensity static electric field have been developed for non-invasive cancer therapy nowadays. The evaluation of the vital organs, one of which is kidney and liver, is necessary for pre-clinical safety assessment. This research aimed to evaluate the effect of the intermediate frequency (150 kHz) and low intensity (18 V...

Previous studies showed that the intensity of electric fields (EF) preferentially inhibits cancer cell division during mitosis at intermediate frequencies. Cancer cells have different physiological activities from normal cells, resulting in different electrical activities between the cancer cells and the surrounding normal tissue. Many researchers...

Researchers have used electric fields as a new therapeutic strategy to treat cancer for the past 15 years. Tumor Treating Fields (TTFields) is an alternating electric field-based cancer therapy approved by the US FDA to treat glioblastoma multiforme (GBM). ECCT (Electro-Capacitive Cancer therapy), a DC charged-discharged electric field (EF) cancer...

Brain Electrical Capacitance Volume Tomography (ECVT) has been developing as an alternative non-invasive brain imaging method. In this study, brain ECVT consisting of two channels, namely a capacitance sensor, is investigated. As a comparison, EEG sensor is used to measure brain activity simultaneously with the brain ECVT. Brain activity measuremen...

The wire-mesh capacitance tomography (WMCT) has been applied to visualize 2D of the distribution of electric field intensity in the treatment planning system (TPS) of electro-capacitive cancer therapy (ECCT) using human head model. WMCT is proposed in this study to estimate accurately the distribution of electric field intensity which is the main o...

Localization of epileptogenic area is a fundamental step in pre-surgical evaluation. Unfortunately, phase II EEG approach has high risk due to invasiveness like infection and bleeding. Therefore, alternative approach with attention to non-invasiveness, real-time measurement and mobility is urgently needed. Brain ECVT is believed to be one of the pr...

Background: Breast cancer is the most common cancer in women worldwide and is the leading cause of death amongst women with cancer. One novel therapy used for breast cancer treatment constitutes non-contact electric fields and is called electro-capacitive cancer therapy (ECCT) with intermediate frequency and low intensity. The objective of this stu...

A non-invasive and non-intrusive monitoring techniques are developed based on the signal capacitance method to observe column flotation performance. In general, gas holdup and bubble flow characteristics are the essential parameters that affect flotation performance. This study investigates and verifies the effects of frother dosage and solid perce...

Brain Electrical Capacitance Volume Tomography (ECVT) has been developed as an emerging non-invasive brain imaging method. As a new method, Brain ECVT needs to be compared with a standardized method such as Electroencephalography (EEG). In this study, a real-time measurement of integrated multichannel EEG-ECVT was done in pre-frontal lobe. The meas...

Background: Breast cancer is the most common cancer in women worldwide and is the leading cause of death in women with cancer. One novel therapy used for breast cancer treatment is non-contact electric fields called electro-capacitive cancer therapy (ECCT) with intermediate frequency (100 kHz) and low intensity (18 Vpp). The objective of this study...

Brain Electrical Capacitance Volume Tomography (Brain ECVT) is a new technique that realizes real-time volumetric imaging of dynamic changes in electrical activity of the brain and allows total interrogation of the whole volume inside a helmet-shaped sensor. The technique has been used for investigating numerous brain functional abnormalities, incl...

Background: Noncontact Electro Capacitive Cancer Therapy (ECCT) is a novel treatment modality in cancer. Chemokine (C-C motif) ligand 2 (CCL2) has a major role in the outgrowth of metastatic breast cancer. Interleukin 18 (IL18) plays a role in macrophage alteration, which leads to excessive angiogenesis. This study aims to elaborate on the associat...

Signal characterization using the capacitive measurement method is studied on the effect of frother dosage in the two-phase column flotation process. The aim of the study is to characterize the signal on the effect of frother dosage. A laboratory flotation column with 0.05 m diameter and 1.25 m height is used for the experiment. Frother of methyl i...

Background: Noncontact Electro Capacitive Cancer Therapy (ECCT) is a novel treatment modality in cancer. Chemokine (C-C motif) ligand 2 (CCL2) has a major role in the outgrowth of metastatic breast cancer. Interleukin 18 (IL18) plays a role in macrophage alteration, which leads to excessive angiogenesis. This study aims to elaborate on the associat...

Wire mesh sensor has been successfully fabricated and used for measurement of the electric field in emulated human body tissue. Measurement of electric field in human body tissue needs to be done, because the electric field is very useful for the treatment especially cancer treatment and also important for health. In this study, we propose a novel...

NN-MOIRT has been proposed earlier as an alternative for existing image reconstruction algorithms that can accurately show a volumetric image in a cylindrical sensor vessel. The Brain ECVT sensor has a different shape and dimensions compared with a common ECVT sensor, which has a cylindrical shape. Using a different sensor changes the image reconst...

Although low energy alternating electric field are gaining an acceptance for electrotherapy of cancer treatment, recent studies have only discussed the electric field distribution characteristics theoretically using numerical approaches. In order to obtain the optimum benefit of low energy alternating electric field, an accurate vector of the low e...

Introduction Non-contact electric fields namely Electro-capacitive Cancer Therapy (ECCT) exposure with low intensity and intermediate frequency (100 KHz) exerted between two capacitive electrodes increased the percentage of cell death of MCF-7 (39.45%). In addition, a pilot study of the safety and efficacy of ECCT performed in 9 C3H mice revealed s...

This paper presents an EEG study for coherence and phase synchrony in mild cognitive impairment (MCI) subjects. MCI is characterized by cognitive decline, which is an early stage of Alzheimer’s disease (AD). AD is a neurodegenerative disorder with symptoms such as memory loss and cognitive impairment. EEG coherence is a statistical measure of corre...

Electrical capacitance volume tomography (ECVT) is proposed as a novel real-time monitoring system for column flotation process. This study aims to validate the results between static and dynamic simulations using ECVT and ECVT-Computational Fluids Dynamics (ECVT-CFD) and real-time column flotation monitoring experiment using ECVT system. Bubble fr...

Electromagnetic tomography method works by utilizing magnetic field induced by coils that are given an electric current. An object with certain conductivity property interferes the magnetic field which will be sensed by the sensor in the form of voltage difference. Experiment using iron as an object has been conducted. In addition, parameters given...

In general, frother and collector are used as reagents to obtain an optimum condition in flotation processes. In this study, the effect of methyl isobutyl carbinol (MIBC) frother and potassium amyl xanthate (PAX) collector on the relative permittivity value using 2-electrode capacitance sensor was conducted. The objective of this study is to know t...

Background: p53 acts as a transcription factor to regulate the expression of genes that modulate various cellular activities. The proliferation of cancer cells has been inhibited under the exposure to low-intensity (18 peak-to-peak voltage) and intermediate-frequency (100 KHz) electric fields generated between 2 capacitive electrodes. Therefore, th...

Electric field distribution analysis generated by ECCT in a human head model with or without brain cancer using wire mesh electrode has been conductedsuccessfully. The analysis of electric field distribution was done using simulation in a human head model with ECCT Apparel Helmet system type A which is three dimensional model. The electric field di...

This paper examines the differences of EEG power and coherence between bipolar disorder patients and healthy subjects in the resting state. Observations are focused on the prefrontal cortex area by calculating intra-hemisphere and inter-hemisphere coherence.EEGdata acquisition are conducted by using wireless Emotiv Epoc on AF3, AF4, FC5, FC6, F7 an...

This research aims to explore the feasibility of capacitance-digital converter and impedance converter for measurement module in electrical capacitancetomography (ECT) system. ECT sensor used was a cylindrical sensor having 8 electrodes. Absolute capacitance measurement system based on Sigma Delta Capacitance-to-Digital-Converter AD7746 has been sh...

This study implemented nearest neighbor algorithm to classifies the position of phantom after scanned using Brain Electrical Capacitance Volume Tomography (ECVT). With k-Nearest Neighbors algorithms, we evaluated 496 values of capacitance measurement to find its nearest neighbors (highest similarity) and classifies its exact position in the sensor....

p>The purpose of this study is to simulate the sensor 32-channel Brain ECVT image reconstruction using ILBP (Iterative Linear Back Projection) methods. ECVT is a dynamic volume imaging technique that utilizes non-linear difference of electric field distribution to determine the distribution of permittivity in the sensing area. ECVT has measured the...

Our research focused on the antiproliferative effect of low intensity (18 Vpp) and intermediate frequency (100 KHz) electrostatic wave between two capacitive electrodes on breast tumor cells in vitro and in vivo. In vitro study has been conducted by using MCF-7 cell lines treated with external electrostatic for 24, 48, and 72 hours of treatment and...

A preliminary study of column flotation monitoring process using electrical capacitance volume tomography (ECVT) was conducted. ECVT was one of the monitoring systems which based on the capacitance measurement. It was used to understand the phenomenon that occurs inside the column in a three-dimensional(3-D)image. A linear back projection (LBP) alg...

The research proposes a design of 12-channel rotary sensor for electrical capacitance volume tomography (ECVT) toward improvement in image reconstruction result. Sensor was assembled by attaching motors at upper section to rotate in radial; also at side to move up and down. Effects of rotating and translating the sensor has been analyzed in compari...

The aim of this study is to simulate the potential distribution of 2D brain geometry based on two electrodes ECVT. ECVT (electrical capacitance tomography) is a tomography modality which produces dielectric distribution image of a subject from several capacitance electrodes measurements. This study begins by producing the geometry of 2D brain based...

Electrical capacitance volume tomography (ECVT) system uses six switches in one channel with configuration resembling “T” letter, so it is called “T-switch”. The working scheme of the switch can be explained in four different modes of operation, i.e. excitation mode, detection mode, ground mode, and floating mode. This research describes the effect...

Electrical capacitance volume tomography (ECVT) system uses six switches in one channel with configuration resembling "T" letter, so it is called "T-switch". The working scheme of the switch can be explained in four different modes of operation, i.e. excitation mode, detection mode, ground mode, and floating mode. This research describes the effect...

This research aims to study brain's electrical signals recorded using EEG as a basis for the diagnosis of patients with Alzheimer's Disease (AD). The subjects consisted of patients with AD, and normal subjects are used as the control. Brain signals are recorded for 3 minutes in a relaxed condition and with eyes closed. The data is processed using p...

A simulation to determine capacitance of brain's electrical activity based on two electrodes ECVT was conducted in this study. This study began with construction of 2D coronal head geometry with five different layers and ECVT sensor design, and then both of these designs were merged. After that, boundary conditions were applied on two electrodes in...

In previous studies, electrical capacitance tomography has been developed and applied for imaging breast tissue to detect abnormalities within the breast caused by simple cysts, benign tumors and malignant cancers. For accurate screening and early detection of such abnormalities, high sensitive capacitance sensor is necessary. This study proposes a...

Analysis of Electroencephalogram (EEG) data, Near Infrared Spectroscopy (NIRS) data, and computer simulation imply that human brains behave chaotically. Moreover the characteristic of brain signals changes from moment to moment, so we propose a new technique to detect the change in chaotic signals of brain, called Moving Maximum Lyapunov Exponents...

4D Brain ECVT is the latest non-invasive brain imaging instrument. In this research, the human brain activity in the prefrontal area during stress and relax conditions was recorded using this instrument, along with measurements of blood pressure, heart rate, and breathing frequency. The data shows that under stress condition, the voltage value of t...

In this study, ECVT brain scanner is used to measure electrical signals generated by the activity of the human brain to the audio response. The basic principle of ECVT is the permittivity distribution mapping of objects based on data measured capacitance. Data capacitance is a response to changes in the permittivity distribution in the brain which...

A capacitance sensor has been designed to investigate the correlation between wood capacitance value, Janka hardness rating and density. The sensor was developed based on parallel plates using copper as the electrodes. Capacitance values were measured using CV-circuit, 20 Vp-p, 2.5 MHz. Five wood specimens from forest plantation that is Karet (Heve...

Each type of coal has different composition and properties, which determine the coal rank. One of the new methods for determining the quality of coal is by measuring its capacitance. It is formerly known that the difference in the moisture content of coal can be determined from the difference in its dielectric properties. The purpose of this paper...

Abstrak Penyakit Alzheimer (Alzheimer's Disease, AD) merupakan gangguan neurodegeneratif progresif yang terkait dengan gangguan fungsi neuronal dan kerusakan kognisi, fungsi, dan perilaku secara bertahap. Ada dua teori tentang penyebab terjadinya AD. Pertama dari luar sel, adanya penumpukan peptida amyloid yang disekresikan oleh sel-sel otak sehing...

Mapping the velocity profile is used to analyze the underlying physics of fluid dynamics either in industrial or processes control. However, existing techniques for real time 3D velocity profile are still on demand to improve. Therefore, in the earlier study, the integration of Tomography Imaging Velocimetry (TIV) based on Electrical Capacitance Vo...

Capacitance measurement accuracy is affected by phase conformity between signal and reference. This work describes phase detection scheme which is necessary for phase synchronization in tomography application. Core processing for calculating phase and amplitude of the detected signal was built on FPGA (Field-Programmable Gate-Array) platform. Phase...

Data acquisition system with single signal conditioning for multi-electrode on electrical capacitance volume tomography (ECVT) was described. ECVT is a method in 3D process imaging based on electrical capacitance. The ECVT hardware is employed to measure capacitance signal from 32 electrodes as sensory module. In this investigation, one signal cond...

Abstrak Otak merupakan organ yang berfungsi mengontrol dan mengkoordinir seluruh aktivitas tubuh manusia. Observasi aktivitas otak dilakukan dengan melakukan pencitraan otak. Teknologi pencitraan yang banyak digunakan untuk observasi aktivitas otak antara lain Positron Emission Tomography (PET), Functional Magnetic Resonance Imaging (fMRI), dan Ele...

This research investigates single excitation signal applied on ECVT (electrical capacitance volume tomography) data acquisition system (DAS). ECVT is one of tomography processes based on capacitance measurement. Excitation signals being used in the system are square and sine waves. Single wave excitation signal was injected into pair electrodes whi...

Background: In our previous study, we have developed a novel sensor for Electrical Capacitance Volume Tomography (ECVT) to map the distribution of tumor inside the human breast. The ECVT provides a volumetric image of permittivity distribution of the breast tissue, showing high permittivity of abnormal tissue characterized with simple cyst, benign...

Planar Magnetic Induction Tomography (PMIT) is an emerging development of Magnetic Induction Tomography (MIT) technique that is developed to overcome a restriction that measurements can only be taken from one surface of materials under testing. The planar sensor design of PMIT makes it quite promising to be applied in Non-Destructive Testing (NDT)...

Planar Magnetic Induction Tomography (PMIT) is an emerging development of Magnetic Induction Tomography (MIT) imaging system that is developed to overcome imaging process restriction that the measurements can only be taken from one surface of conductive materials under testing. The planar design configuration makes it quite attractive to be applied...

A preliminary study about the development of Electrical Capacitance Volume Tomography (ECVT) for determining moisture, calorie and the flow of coal mass real-time on the conveyor has been done. This study aims to examine the capability and sensitivity of ECVT as a capacitance measurement system to investigate the correlation between moisture in coa...

Various defects on welded metal can lead to failure of material, so that it needs some routine examination to maintain the material quality. The development of Magnetic Induction Tomography (MIT) in recent years made MIT a potential method for Non Destructive Test (NDT) to be applied in industries. We perform an MIT inspection technique to detect f...

In this study we performed brain activity observation related to simple tasks of executed movement (EM) and imagined movement (IM) using Electrical Capacitance Volume Tomography (ECVT). ECVT has been previously applied to brain activity imaging and brain cancer detection. This study is intended to elaborate further the previous studies on the brain...

In this study, we have performed the monitoring of copper leaching process using electrical capacitance volume tomography (ECVT). The ECVT has been used to measure electrical signals generated from the copper leaching process and reconstruct volumetric image of the signals in real time. This method is based on the fact that permittivity changes wit...

In Electrical Capacitance Volume Tomography, the internal permittivity distribution of a region of interest has a nonlinear relationship with the measured capacitance. Most image reconstruction algorithms neglects the nonlinear characteristic and use instead a linearized sensitivity approach to solve the non-linear problem, affecting the accuracy o...

ECVT has been widely used in different fields including oil refinery systems, chemical processes, space shuttles and medicals. The technique generates a whole volumetric image from the measured capacitance of the region enclosed by the geometrically three-dimensional sensor. However, the data acquisition and data processing of the ECVT are done on...

Dynamic three-dimensional image electrical capacitance tomography sensor system is disclosed. The technique generates, from the measured capacitance, a whole volume image of the region enclosed by the a geometrically three-dimensional capacitance sensor. A real time, three-dimensional imaging of a moving object or a real time volume imaging (i.e.,...

In this study, for the first time, we have used the ECVT technique, developed earlier for real-time and volumetric imaging of brain activity, to detect the presence of brain tumor. The ECVT sensor system measures the capacitance of electrical signals of the brain on the cortex, and generates a volumetric map of the brain activity on the cortex and...

Proper electrode design to generate uniform sensitivity distribution is crucial for robust volumetric imaging based on electrical capacitance volume tomography (ECVT). Certain designs commonly used in electrical capacitance tomography (ECT), such as rectangular electrodes, form so-called "dead zones", i.e., regions with no variation in sensitivity...

In this research, we proposed a capacitance measurement circuit Electrical Capacitance Volume Tomography (ECVT) to perform three-dimensional image visualization. The ECVT system is consists of three main parts i.e. sensor, data acquisition system, and computer. Data acquisition system is composed of capacitance measurement circuit and microcontroll...