• Proceedings of the KSPS conference
• /
• 2005.11a
• /
• pp.17-20
• /
• 2005

The purpose of this project is to develop a device that can automatically measure pronunciation of English speech produced by Korean learners of English. Pronunciation proficiency will be measured largely in two areas; suprasegmental and segmental areas. In suprasegmental area, intonation and word stress will be traced and compared with those of native speakers by way of statistical methods using tilt parameters. Durations of phones are also examined to measure speakers' naturalness of their pronunciations. In doing so, statistical duration modelling from a large speech database using CART will be considered. For segmental measurement of pronunciation, acoustic probability of a phone, which is a byproduct when doing the forced alignment, will be a basis of scoring pronunciation accuracy of a phone. The final score will be a feedback to the learners to improve their pronunciation.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.6
• /
• pp.91-98
• /
• 2013

Magnetic sensor chip for measuring bio-magnetism is implemented in $0.18{\mu}m$ CMOS technology. The magnetic sensor chip consists of a small-sized high inductance coil sensor and an instrumentation amplifier (IA). High inductance coil sensor with suitable sensitivity and bandwidth for measurement of bio-magnetic signal is designed using electromagnetic field simulation. Low gm operational transconductance amplifier (OTA) using transconductance reduction techniques is designed for on-chip solution. Output signal sensitivity of magnetic sensor chip is $3.25fT/{\mu}V$ and reference noise of 21.1fT/${\surd}$Hz. Proposed IA is designed along with band pass filters(BPF) to reduce magnetic signal noise by using current feedback techniques. Proposed IA achieves a common mode rejection ratio of 117.5dB while the input noise referred is kept below $0.87{\mu}V$.

• Journal of the Institute of Convergence Signal Processing
• /
• v.24 no.1
• /
• pp.15-20
• /
• 2023

In general, maintaining an incorrect sitting posture for a long time is widely known to adversely affect the spine. Recently, several researchers have been interested in the causal relationship between incorrect sitting posture and spinal diseases, and have been studying methods to precisely measure changes in sitting or standing posture to prevent spinal diseases. In previous studies, we have developed a sensor device capable of measuring real-time posture change, applied a momentum calculation algorithm to improve the accuracy of real-time posture change measurement, and verified the accuracy of the postural change measurement sensor. In this study, we developed a posture measurement and analysis device that considers changes in the center of body pressure through the developed sitting pressure measurement, and it confirmed the sensor as an auxiliary tool to increase the accuracy of posture correction training with improving the user's visual feedback.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2001.10a
• /
• pp.111-115
• /
• 2001

A good business performance measurement system is an effective tool io sustained growth in profits. Although interest in creating performance measurement models is widespread, a well-designed system is rare. To be successful in today's competitive environment, a performance measurement system should incorporate strategic success factors and contain financial and non-financial measuring index to carry out strategic management. In the 1990s, Kaplan & Norton introduced a concept called the Balanced Scorecard. The Balanced Scorecard supplements traditional financial measures with criteria that measured performance from three additional perspectives - those perspectives of customers, internal business processes, and learning and growth. This paper presents five measuring index criteria for each perspective. To calculate the relative priority for These measuring index, we investigate weights investigated by interviews with management consultant. Then, AHP method is employed for calculating priority weight. Our evaluation model may be referred to as the Balanced Analytic Hierarchical Performance Model(BAHPM) in the sense that the analytic hierarchical scheme, along with the AHP, is applied. The BAHPM is the first kind of analytical model to cover a wide variety of measures. In comparison with previous evaluation models, our model shows strengths in structural flexibility, ease of incorporating feedback, group evaluation capacity, participation promotion, sensitivity analysis, and computational simplicity. A prototype based on the BAHPM can be applied to various industry sectors.

• The Korean Journal of Emergency Medical Services
• /
• v.19 no.1
• /
• pp.7-17
• /
• 2015

Purpose: We gathered information for the development of a blood pressure measurement education program by analyzing the accuracy of reading taken using a blood pressure simulator by Korean paramedic students. Methods: Data from 131 students were collected in November 12-20, 2013, and April 2-4, 2014. A 27-item questionnaire was administered, the accuracy of measurements confirmed using a blood pressure simulator (BT-CEAB), and the data analyzed (SPSS v 21.0). Results: The accuracy of systolic and diastolic blood pressure readings (${\leq}2mmHg$) was relatively low (27.5%). The mean blood pressure knowledge score was 67.61 points; significant differences were noted considering the sex (p = .001), hours of practice (p =.007), numbers of practice (p = .001), and reported self-confidence (p = .026). The blood pressure measurement accuracy group did not show a significant difference in its knowledge of blood pressure (p = .198). Conclusion: Most subjects needed several practice sessions to master the skill of measuring blood pressure. The feedback provided by individual assessment and the practice education program will serve as the basis for clinical and prehospital practice.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.2
• /
• pp.943-946
• /
• 2005

As a proposed standard for radio resource measurement, 802.11k aims to provide key client feedback to WLAN access points and switches. The proposed standard defines a series of measurement requests and reports that detail Layer 1 and Layer 2 client statistics. In this paper, we analyze handoff processing time, radio specrum usage and handoff coverage using this scheme in home-network inter APs handoff.

• Journal of the Institute of Convergence Signal Processing
• /
• v.9 no.4
• /
• pp.280-287
• /
• 2008

For the reduction of common-mode noise level in Indirect-contact ECG (IDC-ECG) measurement a driven-right-leg grounding method was a lied to the IDC-ECG. Because the IDC-ECG does not require any direct contact between the electrodes and the human skin. it is adequate for un-constraining long-term ECG measurement at home and its various applications are now under development. However, larger 60 Hz noise induced by power line a ears in IDC-BCG than in conventional ECG, that is a restriction of IDC-ECG a application. In this study, the driven-right-leg ground which has been used in conventional direct-contact ECG, was adapted to the IDC-ECG measurement by feedback of the inversion of amplified common-mode noise to the body through the conductive fertile laid on the chair seat By this study, indirect-contact driven-right-leg ground was developed and it was shown to work stably. It was shown that the level of 60Hz power line noise was reduced to about -40 dB when the driven-right-leg gain was 1000. This study shows that we can extend the upper limit of the frequency band of IDC-ECG to 100Hz from 30Hz which is conventional upper limit in IDC-ECG, and we can raise the ground impedance between the body and conductive textile. So it is expected that the application area of the IDC-ECG will be extended by the results of this study.

• Journal of Welding and Joining
• /
• v.24 no.6
• /
• pp.13-20
• /
• 2006

Resistance spot welding is widely used for joining sheet metals in the automotive manufacturing process. Recently, servo-gun is used to increase the productivity and precise control the acting force. However, force control mechanisms have not been investigated with servo-guns until now. In this paper, it is proved that servo-motor current is proportional to torque and by experiment, experimental equation between servo-motor current and electrode force was derived. Algorithm for feedback control of electrode force was suggested using current measurement. In addition, applying soft touch method to this system the impact between electrode and specimen, which is the problem of air gun, could be reduced. Indentation made the force decrease in holding time of resistance spot welding. In order to overcome this problem, force compensation using the servo gun was used and it improved weld strength in good welding current range.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.3
• /
• pp.502-510
• /
• 1997

A disturbance rejection controller using eccentricity filtering and LQ control techniques is proposed to alleviate the effecto of major roll eccentricity in multivariable cold-rolling processes. Fundamental problems in multivariable cold-rolling processes such as process time delay inherent in exit thickness measurement and non-stationary characteristics of roll eccentricity signals can be overcome by the proposed control method. The filtered instantaneous estimate of roll eccentricity may be exploited to improve instantaneous estimate of the exit thickness variation based on roll force and roll gap measurements, and a feedforward compensator is augmented as a reference for a gaugemeter thickness estimator. LQ feedback controller is combined with eccentricity filter for the attenuation of the exit thickness variation due to the entry thickness variation. The simulation results show that the roll eccentricity disturbance is significantly eliminated and other disturbances also are attenuated.

• The Journal of Korean Physical Therapy
• /
• v.24 no.5
• /
• pp.306-312
• /
• 2012

Purpose: The purpose of this study was to examine the effect of changes in foot cutaneous sensation on plantar pressure distribution during gait. Methods: Sixteen healthy young subjects participated in this experiment. All subjects performed two trials of walking under three somatosensory conditions induced by a normal facilitatory insole that provides increased plantar sensory stimulation, and application of lidocaine cream to the plantar surface of the foot to reduce the sensitivity of the soles. Semmes-Weinstein monofilaments were used for evaluation of reduced plantar sensation. The Pedar system was used for measurement of pressure distribution at the plantar surface of the foot. Results: Pressure in the lateral midfoot area showed an increase with increasing and decreasing sensory inputs. When sensory input was increased, plantar pressure showed a decrease in the forefoot area. When sensory input was decreased, plantar pressure showed an increase in the lateral forefoot area and a decrease in the hallux area. Conclusion: By altering sensory feedback, plantar pressure distribution is changed during gait. Plantar cutaneous afferents play an important role in plantar distribution.