D.W. Kim

Optimum electrode configuration for detection of arm movement using bio-impedance.

A four-channel impedance measurement system, including a two-channel goniometer, to analyse human arm movement, was constructed. Impedances and joint angles were simultaneously measured for wrist and elbow movements. As the impedance changes resulting from wrist and elbow movements depended heavily on electrode placement, the optimum electrode configurations for those movements were determined by searching for high correlation coefficients, large impedance changes and minimum interferences in ten subjects (age: 29±6 years). The optimum electrode configurations showed very strong relationships between the wrist joint elbow joint angle and upper arm impedance (correlation coefficient=−0.97±0.03). Although the measured impedance changes of the wrist (1.1±1.5Ω) and elbow (−5.0±2.9Ω) varied between individuals, the reproducibilities of wrist and elbow impedance changes of five subjects were 5.8±1.8% and 4.6±1.4% for the optimum electrode pairs, respectively. It is proposed that this optimum electrode configuration would be useful for future studies involving the accurate measurement of arm movements by the impedance method.

Design of RFID based the Patient Management and Tracking System in hospital

The patient location information in managing for patient workflow will be worked efficiently within the hospital. We designed the Patient Management and Tracking System (PMTS) based on RFID with RSSI(Received Signal Strength Indication) method. This system is able to track the movement of patient in hospital, and manage the waiting-list of patients at a medical office. Therefore, we are sure that the PMTS will be useful for decreasing a duty of medical staff and increase a convenience of patients.

Location Based Blood Bag Management using active RFID and Ubiquitous Sensor Network

This study focuses on the solutions to prevent fatal risk to patients life caused by transfusing blood which is wrong type or has exceeded norm temperature, to protect wrong blood transfusion by a person. We developed and demonstrated the clinical usability of the combined blood temperature management and tracking system using the radio frequency identification (RFID) and the ubiquitous sensor network (USN) Technology. This blood monitoring and management system is continuously report the temperature of the blood-banks refrigerator, track the location of a blood bag, and can confirm that the assigned blood bag was transported to the intended patient in need of transfusion.

Statistical evaluation of the cleft lip nose deformity image.

Cleft lip is a congenital deformity condition with separation of the two sides of the lip and causes nose deformity. Evaluation of surgical corrections and assessment of prognosis in nose deformity depend mainly on doctors subjective judgment. Development of an objective assessment tool in evaluation of the cleft lip nose deformity patients will help in advancement and evaluation of surgical techniques. Therefore, our study aimed on quantitative assessment of a cleft lip nose deformity by comparing following parameters gathered from a photographic image of a cleft lip patient: (1) angle difference between two nostril axes, (2) center of the nostril and distance between two centers, (3) overlapped area of two nostrils and (4) the overlapped area ratio of two nostrils. Assessment results of the nose deformity were statistically analyzed with evaluation results from three highly experienced plastic surgeons. In addition, regression model was developed using correlation relationship and factor analysis of parameters from the results of image analysis

Comparison of digital filters with wavelet multiresolution filter for electrogastrogram

Electrogastrography (EGG) signals have a very low frequency range (0.0083/spl sim/0.15 Hz) and extremely low amplitude (10/spl sim/100 /spl mu/V). Consequently, the EGG signal is easily influenced by noises. Both finite impulse response (FIR) and infinite impulse response (IIR) filters need high order filtering or have phase distortions for passing the very narrow bandwidth of the EGG signals. In this study, we decomposed EGG signals using a wavelet multiresolution method using the Daubechies mother wavelet. The EGG signals were decomposed to seven levels. We reconstructed the signal by summing the decomposed signals from level four to seven. To evaluate the performance of the wavelet multiresolution filter (WMF), we used three indices; signal to noise ratio (SNR) and reconstruction squared error (RSE). The WMF performed better in the SNR and RSE than two kinds of FIR and four kinds of IIR filters.

Calculation of blood volume change in impedance cardiography by a 3-D finite element thoracic model

In this study impedance changes due to aortic expansion during systole was calculated for various electrode configurations in impedance cardiography using a three-dimensional finite element thoracic model. The aorta between the potential electrodes in the model was expanded for the increase of blood volume, 30 ml. The blood volume increase in the aorta was calculated with the basal impedance (Z) and the impedance change (/spl Delta/Z) found from the finite element code using the formula, /spl Delta/vol=/spl rho/(L/Z)/sup 2/ /spl Delta/Z. It was calculated to be 24 ml for the conventional configuration. For the other three ones, they were all closer to 30 ml than the conventional one.<<ETX>>

Automatic stimulus breaker for electric dental pulp tester using pain response

The pulp test provides a means of examining the vitality of dental pulp using physical or chemical stimulation. During electrical pulp testing, an electrical current stimulates the intradental nerve, which may be painful and stressful to patients. The study involved measurement of the electromyogram (EMG) from the anterior belly of the digastric muscle, finger movement and voice response during electrical pulp testing. The excessive stimulus time from the onset time of response (EMG, voice and finger movement) to the end of the stimulation was obtained. The results indicated that the responses occurred in the order: EMG, finger and voice. Based on these results, an automatic stimulus shut-off circuit was developed using the above-mentioned responses to stimulus during electric pulp testing. Excessive stimulus time was reduced by prompt switching-off of the pulp tester output, 64 ms on average after the first detected response (EMG). Consequently, excessive stimulus times were reduced by 284 and 152 ms on average for the subject and examiner disconnection, respectively, using the developed automatic shut-off circuit. Therefore it was possible to minimise pain and stress by reducing excessive pulp stimulation.

Minimizing Excessive Stimulus during Electric Pulp Testing

Electric pulp test is a method to examine the vitality of dental pulp using the electrical stimulation. During the pulp test, the current stimulates intradental nerve, and give severe pain to patients. Some studies were accomplished to measure the responses of subjects by stimulating over the sensory threshold. But these studies were focused on the time delay of subjects response after stimulating over the threshold. The purpose of this study was first to measure the excessive stimulation time during pulp testing by means of EMG in anterior belly of digastric muscle, voice, and finger movement, secondly, to determine whether the excessive stimulation time could be reduced by the specially designed automatic circuit breaker on the basis of EMG signal

Minimization of influence by the upper eyelid droop in measuring 3-D eye movements

A system to measure three-dimensional (horizontal, veritical, and torsional) eye movement consisted of a personal computer, CCD camera, and frame grabber. We proposed a fast algorithm minimizing the influence of upper eyelid droop, and compared it to the center of gravity, maximum likelihood, and histogram algorithms. The proposed algorithm had excellent performance in respect of the speed of eye tracking and the robustness for the upper eyelid droop.

Quantitative evaluation of rabbit's hepatic function by HEF, DISADA-K, and ICG R/sub max/ methods

The hepatic extraction fraction (HEF), DISIDA-K, and ICG R/sub max/ were obtained to evaluate hepatic function for two normal and four abnormal rabbits with rapidly damaged livers. The correlation coefficients among these three methods were found. The correlation coefficient between the HEF and ICG R/sub max/ which is a standard technique in evaluating hepatic function was found to be 0.93. Therefore the HEF is assumed to be a valuable diagnostic method since it is not only accurate and simple, but possible to estimate remaining hepatic function after surgical removal of cancerous hepatic tissues.