• Journal of Oral Medicine and Pain
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• v.31 no.3
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• pp.223-229
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• 2006

The objectives of this study was to investigate the amount of tooth ablation and the change of intrapulpal temperature by Er:YAG laser as it relates to pulse energy and pulse repetition rate at the identical power and, thereby, to reveal which of the two parameters strongly relates with ablation efficiency and intrapulpal temperature. Extracted healthy human molar teeth were sectioned into two pieces and each specimen was irradiated within the combination of pulse energy and pulse repetition time at the same power of 3W; $300mJy{\times}10Hz$ group, $200mJy{\times}15Hz$ group, and $150mJy{\times}20Hz$ group. Each specimen comprised ten tooth specimens. A laser beam with conjunction of a water flow rate of 1.6 ml/min was applied over enamel surfaces of the specimens during 3 seconds and the ablation amount was determined by difference in weight before and after irradiation. To investigate the temperature change in the pulp according to the above groups, another five extracted healthy human molar teeth were prepared. Each tooth was embedded into resin block and the temperature-measuring probes were kept on the irradiated and the opposite walls in the dental pulp during lasing. When the power was kept constant at 3W, ablation amount increased with pulse energy rather than pulse repetition rate (p=0.000). Although intrapulpal temperature increased with pulse repetition rate, there were no significant differences among the groups and between the irradiated and the opposite pulpal walls, except at a condition of $150y{\times}20Hz$ (p=0.033). Conclusively, it is suggested that ablation efficacy is influenced by pulse energy rather than pulse repetition rate.

• The Journal of Internal Korean Medicine
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• v.3 no.1
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• pp.23-32
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• 1986

As a result of administration of Coptidis Rhizoma extract and Zingiberis Rhizoma extract to Rat and Rabbit, its effect to the Gastric Juice Volume, Acidity, Pepsin out put of Rat and the movement of Intestine, Pulse Rate of Rabbit was as follows; 1. In the secretion of Gastric Juice, the Juice Volume in Coptidis Rhizoma administered group in contrast to Control Group, has increased in 30mg the increasing rate 21.4%, and has decreased in 300mg the decreasing rate 113.9%. But the Juice Volume in Zingiberis Rhizoma administered group has all decreased in 12, 30, 60, 120mg, and has remarkably decreased in 60mg the decreasing rate 62.9%. 2. The Gastric Acidity in Coptidis Rhizome administered group, in contrast to Control Group, has increased in 30, and 75mg, but no significant value, and has decreased in 300mg the decreasing rate 104.7%. But the Gastric Acidity in Zingiberis Rhizoma administered group has all decreased in 12, 30, 60 120mg, and has remarkably decreased in 60mg the decreasing rate 105.6%. 3. The Pepsin out-put in Coptids Rhizoma administered group, in contrast to Control group, has increased in 30mg the increasing rate 30.3%, and has decreased in 150, 300mg, no significant value. But the Pepsin out-put in Zingiberis Rhizoma administered group has all decreased in 12, 30, 60, 120mg, and has remarkably decreased in 60mg the decreasing rate 86.4%. 4. In the movement of Intestine, the contraction Coptidis Rhizoma administered group, in contrast before the administration, has increased in 12mg, but has begun to decrease in 30mg, and has remarkably decreased in 70mg. The contraction in Zingiberis Rhizoma administered group, in contrast before the administration, has all increased in 30, 60, 120mg. 5. In Pulse Rate, the pulsation, in contrast to Control group after 60, 120 180, 240min. has decreased in Coptidis Rhizoma administered group, and has increased in Zingiberis Rhizoma administered group, but no significant value.

• Journal of Oral Medicine and Pain
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• v.30 no.3
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• pp.375-381
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• 2005

Er:YAG laser has been considered a promising alternative to dental drill and many researches indicate that adjustment to variable parameters, including water flow rate, pulse energy and pulse repetition rate, can be made to improve ablation ability and efficiency of the laser. Of these parameters, addition of water spray during irradiation has been thought to ablate dental hard tissue more rapidly and safely. The purpose of this study was to investigate tooth ablation amount by Er:YAG laser irradiation as related to varied water flow rates added and, ultimately to find the most effective water flow rate for ablation. In addition, the temperature change of pulp chamber during irradiation was also monitored on the irradiated and opposite pulpal walls, respectively. An Er:YAG laser with contact mode was employed. Extracted human molars were split into two pieces for ablation experiment. Pulse energies of 200 and 300 mJ with a pulse repetition rate of 20 Hz and 5 water flow rates (1.6, 3.0, 5.0, 7.0, and 10.0 ml/min) were applied. Each irradiation was performed for 3 seconds. According to these parameters, experimental groups were divided into 10 subgroups which consisted of 5 specimens. For temperature experiment, another 5 tooth-specimens were prepared in the manner that pulp chamber was open through access cavity preparation and two temperature-measuring probes were placed respectively on the irradiated and the opposite walls of pulp chamber. From the experiment on ablation amount related to different water flow rates, it was shown that the least water flow rate of 1.6 ml/min ablated more than any other water flow rates (p<0.000). When the irradiation for 3 seconds, combined with the pulse repetition time of 20Hz and the water flow rate of 1.6 ml/min was done to tooth specimen, the temperature rise was not noticeable both on the irradiated and the opposite pulpal walls (less than 3$^{\circ}C$) and there was no significant difference in temperature rise between the two pulse energies, 200 and 300 mJ. From the results of this study, it is suggested that tooth ablation with Er:YAG laser can be done effectively and safely at a energy between 200 and 300 mJ/pulse and a pulse repetition rate of 20 Hz when the lasing is conjugated with the water flow rate of 1.6ml/min.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.75-78
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• 1995

This paper presents the feasibility of laser ablation process in 3-D micro machining of MEMS (micro Electro Mechanical System)parts. The micro machining characteristics of polymer(Energy fluence, pulse repetition rate, number of pulse, ablation rate)are investigated and 3-D micro machined samples are demonstrated.

• Journal of the Ergonomics Society of Korea
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• v.2 no.2
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• pp.3-10
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• 1983

While three subjects were running on treadmill at five different speeds, their heart beat interval times were measured and analyzed. From the analysis, we discovered some relation- ships between workload and cardiac response, especially cardiac arrhythmia. Using these relationships, a physioligical model for estimating workload was developed. Although pulse rate has been considered as a good measure of physical load, this study shows that it is highly subject dependent and therefore unsuitable for task evalution. It is recommended to use range of heart beat interval times rather than pulse rate in the evaluation of light work.

• Journal of the Korean Society of Propulsion Engineers
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• v.1 no.1
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• pp.64-72
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• 1997

An analytical study has been performed to investigate the unsteady ignition characteristics of pulse combustion. In many combustion applications, strain rate of the flow can significantly affect the combustion features; ignition, extinction, and reignition. In the pulse combustion, two jets (hot combustion gases and fresh mixtures) coming from the opposite side of the combustor will collide in the combustor forming a stagnation region where the chemical reaction is suppressed by the strain rate until this becomes below the critical value. In this research, the method of large activation energy asymptotic is adopted with one step irreversible kinetics to examine the ignition response to the periodic variation of the strain rate of flow. The results show the variation of the maximum value of strain rate can determine whether the ignition or extinction occur.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.2
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• pp.121-131
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• 1992

In this paper, three methods are studied to enhance the performance of SBC ( Sub-Band Coding )schemes for voice signal at the medium bit rate between 12 kbps and If; kbps, and adaptive postfilteritng using human auditory characteristics Is (Bone at the decoder out put. First, GQMF(Generalized Quadrature Mirror Filter ) Is used instead of QME'((Quadrature MirrorFiltcr ) to have better performance. Second, by adaptive bit allocation to each sub-band, speech quality is enhanced and valuable rate ceding If possible. Third, corriparlson study oS thr: coder performance using APCM(Adaptive Pulse Code ModulatioTi) and ADPCM( Adaptive Differentiai Pulse Code Modulatiori) , Indicates that SB AfCM performance better than the other. Adaptive postfiltering at the decoder output enhances the quality of the coded speech. The two proposed postfiltering methods decrease the noise sufficiently at the expense of the low computational load.

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.281-287
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• 1984

In search for a method of evaluating the cardiopulmonary function. 74 male and 33 female volunteers ages $18{\sim}25$ were subjected to this study The subjects walked on a treadmill at speed of 2,4,6 and 8km/hr with 0,5,10,15,20 and 25% grade of inclination, respectively, for a measurement of heart rate and oxygen-pulse. Heart rate was measured every 5 seconds at resting state and during walking by telemetric method using Heart Checker 108 System (Senoh Co., Japan). Oxygen concentration was measured by Douglas bag method collecting expired air for 5 minutes at rest, and for 2 minutes at the end of each walking exercise. Oxygen concentration in an expired air was analyzed with Orzat gas analyser and expressed in terms of STPD. Oxygen-pulse was defined as an amount of oxygen consumed at every heart at a cellular level. The followings were the results obtained from this study. 1. Mean values of oxygen-pulse at resting state was $3.1{\pm}0.11ml/beat$ in male and $2.5{\pm}0.87ml/beat$ in female, respectively. 2. Mean values of oxygen-pulse during treadmill walking were increased in proportion with the load of exercise, namely, the speed and grade of inclination, from minimum of 7.1ml/beat upto maximum of 18.2ml/beat in male and from minimum of 4.2ml/beat upto maximum of 12,7ml/beat in female. 3. Both linear and logarithmic regressional relationships between oxygen-pulse and speed of walking and grade of inclination were observed in both sexes. Predicted values of oxygen-pulse by logarithmic regressional formula on speed and on grade of inclination were better coincided with the measured values than those predicted by the linear regressional formula.

• Journal of Digital Convergence
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• v.12 no.11
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• pp.387-393
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• 2014

In this research, we aimed to investigate the most optimum pulse wave sensor to ear label of live stocks among pulse wave piezo film sensor, conductive textile sensor, photo sensor. As a result of this research with application to 10 cattle, 10 pigs objects with pulse wave piezo film sensor, conductive textile sensor, photo sensor, photo sensor shows less standard deviation to average value than piezo film sensor or conductive textile sensor which means it is the most stable for the cattle. With pigs, piezo film sensor, conductive textile sensor and photo sensor all show stable pulse rate. Thus, to take pulse rate of livestock with curved body and long and dense coat such as cow, photo sensor will be considered as the most efficient mean.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1978_1979
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• 2009

Heart rate may be a very important parameter in human health. To extract heart rate, the electrocardiogram(ECG) is commonly used. But the ECG acquisition procedure is somewhat complex. On the other hand, the acquisition of pulse wave or photoplethysmogram(PPG) is very easy. However, the peak of PPG is not so sharp as ECG. This study tries to enhance the performance of period detection in PPG signal. The method uses the average slopes around the main peak. The crossing point of the increasing and the decreasing slopes is selected as the peak point of heart rate period. The proposed method showed smoothed heart rate graph and reduced irregularity in heart rate values.