• Title/Summary/Keyword: Frequency measurement

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Measurement and Quality Control of MIROS Wave Radar Data at Dokdo (독도 MIROS Wave Radar를 이용한 파랑관측 및 품질관리)

  • Jun, Hyunjung;Min, Yongchim;Jeong, Jin-Yong;Do, Kideok
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.32 no.2
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    • pp.135-145
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    • 2020
  • Wave observation is widely used to direct observation method for observing the water surface elevation using wave buoy or pressure gauge and remote-sensing wave observation method. The wave buoy and pressure gauge can produce high-quality wave data but have disadvantages of the high risk of damage and loss of the instrument, and high maintenance cost in the offshore area. On the other hand, remote observation method such as radar is easy to maintain by installing the equipment on the land, but the accuracy is somewhat lower than the direct observation method. This study investigates the data quality of MIROS Wave and Current Radar (MWR) installed at Dokdo and improve the data quality of remote wave observation data using the wave buoy (CWB) observation data operated by the Korea Meteorological Administration. We applied and developed the three types of wave data quality control; 1) the combined use (Optimal Filter) of the filter designed by MIROS (Reduce Noise Frequency, Phillips Check, Energy Level Check), 2) Spike Test Algorithm (Spike Test) developed by OOI (Ocean Observatories Initiative) and 3) a new filter (H-Ts QC) using the significant wave height-period relationship. As a result, the wave observation data of MWR using three quality control have some reliability about the significant wave height. On the other hand, there are still some errors in the significant wave period, so improvements are required. Also, since the wave observation data of MWR is different somewhat from the CWB data in high waves of over 3 m, further research such as collection and analysis of long-term remote wave observation data and filter development is necessary.

Measurement of the Quantity of Hydrogen Peroxide Produced in the Ultrasound-irradiated Aqueous Solution of Organic Compounds (초음파를 조사(照射)한 유기화합물 수용액 속에서의 과산화수소 생성량의 측정)

  • Mo, Se-Young;Chang, Hong-Ki;Lee, Kyung-Jae;Jang, Gun-Eik;Sohn, Jong-Ryeul
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.1
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    • pp.61-71
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    • 2000
  • When irradiate the power ultrasound into the aqueous solutions, water vapor is decomposed by the heat of very high temperature in the cavitation bubble to produce OH (hydroxyl radical) and H (hydrogen radical), and these radicals play a role in decomposing the substances in aqueous solution by oxidation and/or reduction, and in producing the hydrogen peroxide. Accordingly it is possible to predict that the quantity of hydrogen peroxide produced may correlate with the sonolysis mechanism of the substance in aqueous solution. Thus to confirm this prediction, the quantities of hydrogen peroxide produced from each of the air saturated distilled water and three aqueous solutions of TCE, benzene, and 2,4-DCP that are prepared by dissolving them into distilled water are measured. As a result, it showed that the quantity of hydrogen peroxide produced from the distilled water and three aqueous solutions are increased in order of distilled water>TCE solution>2,4-DCP solution>benzene solution, and decrease with decrease in concentration of organic substance, which coincide with the sonolysis mechanisms reported that TCE in aqueous solution is decomposed directly by the pyrolysis in and around the cavitation bubbles when its concentration is high and by the radical reaction when low, however, benzene and 2,4-DCP are decomposed not only by the pyrolysis but also by the radical reactions. Effects of such experimental parameters as the acoustic frequency and power and as the concentration showed that the higher the acoustic frequency and the lower the acoustic power, the less the quantity of hydrogen peroxide was produced. This result coincide with the theory of ultrasound for the relation between the cavitation that is the energy source of the power ultrasound in aqueous solution and these experimental parameters.

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A Systematic Study on the Multifaceted Lifestyle Assessment Tools For Community-dwelling Elderly: Trend and Application Prospect (지역사회 거주 고령자의 라이프스타일 측정도구에 관한 조사: 경향과 활용전망)

  • Park, Kang-Hyun;Won, Kyung-A;Park, Ji-Hyuk
    • Therapeutic Science for Rehabilitation
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    • v.8 no.3
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    • pp.7-29
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    • 2019
  • Objective: The purpose of this study is to analyze comprehensive lifestyle assessment and other assessments which evaluate essential lifestyle factors, including physical activity, nutrition and activity participation. Methods: To analyze the comprehensive lifestyle assessment, from January 2001 to June 2019, a literature search was conducted using the CINANL, NDSL, PubMed, and RISS databases. The search terms were 'lifestyle assessment' OR 'lifestyle profile' OR 'lifestyle test'. In terms of other assessments of essential factors of lifestyle, from January 2010 to June 2019, articles were searched using similar databases. The search terms were 'physical activity assessment' OR 'physical activity participation profile', 'nutrition assessment', 'activity participation assessment' OR 'activity participation and lifestyle'. Results: A total of 4,165 articles were obtained, and finally 31 articles were selected according to the inclusion criteria. Among 31 articles, there were five with comprehensive lifestyle assessments, and all of them were self-report questionnaires. The most popular assessments were the Health Enhancement Lifestyle Profile (HELP) and the Health-Promoting Lifestyle Profile (HPLP), which were used in three articles (33%). In terms of assessment of physical activity, the most frequently used evaluation method was the self-report questionnaire, which was used in seven articles (58%) followed by objective assessments, which were used in four articles (33%). It was demonstrated that the Mini-Nutritional Assessment (MNA) was the most frequently used for nutrition assessment in the elderly. There were five types of assessment tool used for activity participation. Among them, meaningful activity participation assessment (MAPA) was the most frequently used tool. Conclusion: As a result of the systematic review, it was found that there are 21 assessments related to the evaluation of lifestyle in the elderly. Most assessments employed the self-report questionnaire method and mainly evaluated frequency and duration of participation in drinking, smoking, exercise, nutrition and social activities. Assessments of essential lifestyle factors were the self-report questionnaire method and the participation and frequency of activity. Therefore, by analyzing assessment tools, types of items and measurement methods of comprehensive lifestyle assessments and other assessment of essential lifestyle factors, this study provides the basic data on which to develop a standardized assessment tool that can evaluate the multifaceted lifestyle profile of the elderly.

Comparisons of Soil Water Retention Characteristics and FDR Sensor Calibration of Field Soils in Korean Orchards (노지 과수원 토성별 수분보유 특성 및 FDR 센서 보정계수 비교)

  • Lee, Kiram;Kim, Jongkyun;Lee, Jaebeom;Kim, Jongyun
    • Journal of Bio-Environment Control
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    • v.31 no.4
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    • pp.401-408
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    • 2022
  • As research on a controlled environment system based on crop growth environment sensing for sustainable production of horticultural crops and its industrial use has been important, research on how to properly utilize soil moisture sensors for outdoor cultivation is being actively conducted. This experiment was conducted to suggest the proper method of utilizing the TEROS 12, an FDR (frequency domain reflectometry) sensor, which is frequently used in industry and research fields, for each orchard soil in three regions in Korea. We collected soils from each orchard where fruit trees were grown, investigated the soil characteristics and soil water retention curve, and compared TEROS 12 sensor calibration equations to correlate the sensor output to the corresponding soil volumetric water content through linear and cubic regressions for each soil sample. The estimated value from the calibration equation provided by the manufacturer was also compared. The soil collected from all three orchards showed different soil characteristics and volumetric water content values by each soil water retention level across the soil samples. In addition, the cubic calibration equation for TEROS 12 sensor showed the highest coefficient of determination higher than 0.95, and the lowest RMSE for all soil samples. When estimating volumetric water contents from TEROS 12 sensor output using the calibration equation provided by the manufacturer, their calculated volumetric water contents were lower than the actual volumetric water contents, with the difference up to 0.09-0.17 m3·m-3 depending on the soil samples, indicating an appropriate calibration for each soil should be preceded before FDR sensor utilization. Also, there was a difference in the range of soil volumetric water content corresponding to the soil water retention levels across the soil samples, suggesting that the soil water retention information should be required to properly interpret the volumetric water content value of the soil. Moreover, soil with a high content of sand had a relatively narrow range of volumetric water contents for irrigation, thus reducing the accuracy of an FDR sensor measurement. In conclusion, analyzing soil water retention characteristics of the target soil and the soil-specific calibration would be necessary to properly quantify the soil water status and determine their adequate irrigation point using an FDR sensor.

Development and assessment of pre-release discharge technology for response to flood on deteriorated reservoirs dealing with abnormal weather events (이상기후대비 노후저수지 홍수 대응을 위한 사전방류 기술개발 및 평가)

  • Moon, Soojin;Jeong, Changsam;Choi, Byounghan;Kim, Seungwook;Jang, Daewon
    • Journal of Korea Water Resources Association
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    • v.56 no.11
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    • pp.775-784
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    • 2023
  • With the increasing trend of extreme rainfall that exceeds the design frequency of man-made structures due to extreme weather, it is necessary to review the safety of agricultural reservoirs designed in the past. However, there are no local government-managed reservoirs (13,685) that can be discharged in an emergency, except for reservoirs over a certain size under the jurisdiction of the Korea Rural Affairs Corporation. In this case, it is important to quickly deploy a mobile siphon to the site for preliminary discharge, and this study evaluated the applicability of a mobile siphon with a diameter of 200 mm, a minimum water level difference of 6 m, 420 (m2/h), and 10,000 (m2/day), which can perform both preliminary and emergency discharge functions, to the Yugum Reservoir in Gyeongju City. The test bed, Yugum Reservoir, is a facility that was completed in 1945 and has been in use for about 78 years. According to the hydrological stability analysis, the lowest height of the current dam crest section is 27.15 (EL.m), which is 0.29m lower than the reviewed flood level of 27.44 (EL.m), indicating that there is a possibility of lunar flow through the embankment, and the headroom is insufficient by 1.72 m, so it was reviewed as not securing hydrological safety. The water level-volume curve was arbitrarily derived because it was difficult to clearly establish the water level-flow relationship curve of the reservoir since the water level-flow measurement was not carried out regularly, and based on the derived curve, the algorithm for operating small and medium-sized old reservoirs was developed to consider the pre-discharge time, the amount of spillway discharge, and to predict the reservoir lunar flow time according to the flood volume by frequency, thereby securing evacuation time in advance and reducing the risk of collapse. Based on one row of 200 mm diameter mobile siphons, the optimal pre-discharge time to secure evacuation time (about 1 hour) while maintaining 80% of the upper limit water level (about 30,000 m2) during a 30-year flood was analyzed to be 12 hours earlier. If the pre-discharge technology utilizing siphons for small and medium-sized old reservoirs and the algorithm for reservoir operation are implemented in advance in case of abnormal weather and the decision-making of managers is supported, it is possible to secure the safety of residents in the risk area of reservoir collapse, resolve the anxiety of residents through the establishment of a support system for evacuating residents, and reduce risk factors by providing risk avoidance measures in the event of a reservoir risk situation.

Evaluation of Sodium Intake and Relationship between Sodium Intake and the Bone Mineral Density of Female University Students (중부 지역 여대생에서 음식섭취빈도조사지를 이용한 나트륨 섭취량 평가 및 나트륨 섭취와 골밀도와의 관련성 조사)

  • Bae, Yun-Jung;Yeon, Jee-Young
    • Journal of the East Asian Society of Dietary Life
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    • v.21 no.5
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    • pp.625-636
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    • 2011
  • The purpose of this study was to evaluate the relationship between bone health and sodium intake in female university students using a dish frequency questionnaire (DFQ 125), anthropometric checkups, food records for 3 days, and ultrasound measurement of calcaneus bone mineral density. Subjects were divided into two groups: normal (n=196) and osteopenia (n=52). There were no significant differences in age or height between the two groups. The average weight, body mass index, and body fat in the normal group were significantly higher than in the osteopenia group. The sodium intake of DFQ was positively correlated with the sodium intake of 3 days of dietary records (p=0.0003). There were no significant differences in the sodium intake between the two groups from DFQ. The dishes were ranked by sodium intake: kimchies were 17.68%, noodles and mandu were 16.36%, stews were 13.69%, main dishes such as meat, egg, and beans were 11.47%, and fish and shellfish were 11.07%. The frequency of eating noodles and mandu (p=0.0116), stews (p=0.0008), kimchies (p=0.0482), fish and shellfish (p=0.0362), vegetables (p=0.0064) and seasoning (p=0.0347) were negatively associated with bone mineral density. Bone health was not significantly different with increasing quartiles of sodium intake. As excessive sodium intakes may indirectly affect bone mineral density, these results suggest that to prevent osteoporosis, university students needed to be more educated about diets containing less sodium through nutrition education programs.

A study of $Smartpeg^{TM}'s$ lifetime according to sterilization for implant stability (임플랜트 안정성을 위한 자기공명막대의 소독방법에 따른 수명에 관한 연구)

  • Won, Ho-Yeon;Cho, In-Ho;Lee, Joon-Seok
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.1
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    • pp.42-52
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    • 2008
  • Purpose: Resonance Frequency Analysis(RFA) technique can be used as an effective method in measuring the implant stability and documenting the clinical results. This technique also determines how stable the implant is before performing a prosthetic practice. Having become one the guidelines of the implant therapy whose final objective is the immediate loading, the $Osstell^{TM}$ mentor is giving a lot of information to the clinicians recently. In this communication, experiments were performed to investigate how reliable the measured ISQ values by $Osstell^{TM}$ mentor are, and to see if those are also stable even after sterilization. As five objectives: 1) How stable measured ISQ values after fixation $Smartpeg^{TM}s$ for 400 times. 2) How stable measured ISQ values after 'attach-detach'$Smartpeg^{TM}'s$ for 400 times. 3) How stable measured ISQ values after clinical sterilization methods. 4) How stable measured ISQ values after repeatedly sterilization in autoclave for 10 times. 5) What is the critical temperature which is lost the magnetism of $Smartpeg^{TM}$. Materials and Methods: Clinical sterilization methods(Autoclave sterilization, Dentistar sterilization, Ultra violet sterilization, Vacuum dry unit sterilization, Boiling water sterilization, combined $H_{2}O_{2}$ and Alcohol sterilization).$Smartpeg^{TM}s$. D3 Block bone($3{\times}9{\times}2cm$). Osstem implant(${\emptyset}4.1$-10mm).$Osstell^{TM}$ mentor. Individual experiment was used 8 number of $Smartpeg^{TM}s$ and they had measured to ISQ values of before experiment and after experiment. Results: 1. The measured ISQ values did not change after fixation $Smartpeg^{TM}s$ for 400 times. 2. There was no significant changes in the measured ISQ values of 'attach-detach $Smartpeg^{TM}s'$ for 400 times. 3. The measured ISQ values did not change after the usual clinical sterilization methods. 4. The measured ISQ values did not change after sterilization in autoclave for 10 times. 5. It was impossible to exactly measure the critical temperature which is lost the magnetism of $Smartpeg^{TM}s$. But, the results was resulted to lost its magnetism in higher temperature than $150^{\circ}C$/10 minute. Conclusion: The measured ISQ values showed insignificant differences in case of no changes in the magnetism of the $Smartpeg^{TM}s$. It seems that the $Smartpeg^{TM}s$ can be used repeatedly in every measurement if the original magnetisms of the $Smartpeg^{TM}s$ can be recognized. There seems to be no significant changes in the measured ISQ values of 'attach-detach $Smartpeg^{TM}s'$ only if the screw pitches were unimpaired. The clinical sterilization methods seems acceptable because the result was resulted to lost its magnetism in higher temperature than $150^{\circ}C$/10minute.

Measuring the Public Service Quality Using Process Mining: Focusing on N City's Building Licensing Complaint Service (프로세스 마이닝을 이용한 공공서비스의 품질 측정: N시의 건축 인허가 민원 서비스를 중심으로)

  • Lee, Jung Seung
    • Journal of Intelligence and Information Systems
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    • v.25 no.4
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    • pp.35-52
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    • 2019
  • As public services are provided in various forms, including e-government, the level of public demand for public service quality is increasing. Although continuous measurement and improvement of the quality of public services is needed to improve the quality of public services, traditional surveys are costly and time-consuming and have limitations. Therefore, there is a need for an analytical technique that can measure the quality of public services quickly and accurately at any time based on the data generated from public services. In this study, we analyzed the quality of public services based on data using process mining techniques for civil licensing services in N city. It is because the N city's building license complaint service can secure data necessary for analysis and can be spread to other institutions through public service quality management. This study conducted process mining on a total of 3678 building license complaint services in N city for two years from January 2014, and identified process maps and departments with high frequency and long processing time. According to the analysis results, there was a case where a department was crowded or relatively few at a certain point in time. In addition, there was a reasonable doubt that the increase in the number of complaints would increase the time required to complete the complaints. According to the analysis results, the time required to complete the complaint was varied from the same day to a year and 146 days. The cumulative frequency of the top four departments of the Sewage Treatment Division, the Waterworks Division, the Urban Design Division, and the Green Growth Division exceeded 50% and the cumulative frequency of the top nine departments exceeded 70%. Higher departments were limited and there was a great deal of unbalanced load among departments. Most complaint services have a variety of different patterns of processes. Research shows that the number of 'complementary' decisions has the greatest impact on the length of a complaint. This is interpreted as a lengthy period until the completion of the entire complaint is required because the 'complement' decision requires a physical period in which the complainant supplements and submits the documents again. In order to solve these problems, it is possible to drastically reduce the overall processing time of the complaints by preparing thoroughly before the filing of the complaints or in the preparation of the complaints, or the 'complementary' decision of other complaints. By clarifying and disclosing the cause and solution of one of the important data in the system, it helps the complainant to prepare in advance and convinces that the documents prepared by the public information will be passed. The transparency of complaints can be sufficiently predictable. Documents prepared by pre-disclosed information are likely to be processed without problems, which not only shortens the processing period but also improves work efficiency by eliminating the need for renegotiation or multiple tasks from the point of view of the processor. The results of this study can be used to find departments with high burdens of civil complaints at certain points of time and to flexibly manage the workforce allocation between departments. In addition, as a result of analyzing the pattern of the departments participating in the consultation by the characteristics of the complaints, it is possible to use it for automation or recommendation when requesting the consultation department. In addition, by using various data generated during the complaint process and using machine learning techniques, the pattern of the complaint process can be found. It can be used for automation / intelligence of civil complaint processing by making this algorithm and applying it to the system. This study is expected to be used to suggest future public service quality improvement through process mining analysis on civil service.

Variation of Vital Sign according to Time in Full Immersion of Hot and Cool Bath (온.냉욕 전신침수욕시 기간에 따른 vital sign의 변화)

  • Yi, Seung-Ju
    • Journal of Korean Physical Therapy Science
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    • v.3 no.3
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    • pp.35-49
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    • 1996
  • This study was conducted to see variation of vital sign of hot and cool bath according to time, a questionnair survey and measurement was carried out for 32 students(sophomore) of department of physical therapy Andong Junior College on the 27th of June, 1995. The result were as follows: The average systolic blood pressure(SBP) of stability for 32 college students who were measured was 105.3mmHg, the average diastolic blood pressure(DBP) was 67.3mmHg, the average pulse frequency(PF) was 70.7(frequency/min), the average respiratory frequency (RF) was 15.6 (frequency/min), and the body temperature(BT) was $36.6^{\circ}C$. As time went on, SBP for 32 students who were measured in hot bath according to stability, 3 min, 6 min, 9 min, and 12 min was decreased(105.15 mmHg, 104.69mmHg, 104.24 mmHg, 103.03 mmHg, and 96.69 mmHg)(P=0.3006). SBP was decreased in cool bath, too(105.15 mmHg, 103.33 mmHg, 103.33 mmHg, and 100.91 mmHg), but it at 12 min was a little higher(l03.09 mmHg)(P=0.7566). As time went on, DBP according to stability, 3 min, 6 min, 9 min, and 12 minutes was decreased in hot bath(66.82 mmHg, 65.45 mmHg, 64.54 mmHg, 63.03 mmHg, and 59.39 mmHg)(P=0.0906). It was similar in cool bath(66.82 mmHg, 67.87 mmHg, 68.48 mmHg, 67.87 mmHg, and 68.78)(P=0.9654). As time went on, PF was significantly increased in hot bath(70.42 times, 86.96 times, 93.57 times, 99.30 times, and 101.78 times)(P=0.0001). It was a little increased in cool bath, too (70.42 times, 70.85 times, 71.63 times, 71.06 times, and 71.45 times)(P=0.9803). As time went on, RF was significantly increased in hot bath(15.75 times, 19.09 times, 22.09 times, 24.94 times, and 26.48 times)(P=0.0001). I t in cool bath of stability, 3 min, and 6 min was a little increased(15.75 times, 19.30 times, 19.39 times), but it in 9 min(18.67 times), and 12 min(18.09 times) was a little decreased(P=0.0176). As time went on, BT was significantly increased in hot bath($36.63^{\circ}C,\;37.45^{\circ}C,\;37.81^{\circ}C,\;38.12^{\circ}C,\;38.33^{\circ}C$)(P=0.0001). It was a little increased in cool bath of stability and 3 min($36.63^{\circ}C,\;37.40^{\circ}C$), but others are similar($37.33^{\circ}C,\;37.37^{\circ}C$, and $37.36^{\circ}C$)(P=0.0001). It was revealed by this study, SBP and DBP according to time in hot and cool bath were decreased. PF, RF, and BT in hot bath were higher, RF and BT in cool bath were higher too. but PF was similar.

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A STUDY ON THE TEMPERATURE CHANGES OF BONE TISSUES DURING IMPLANT SITE PREPARATION (임플랜트 식립부위 형성시 골조직의 온도변화에 관한 연구)

  • Kim Pyung-Il;Kim Yung-Soo;Jang Kyung-Soo;Kim Chang-Whe
    • The Journal of Korean Academy of Prosthodontics
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    • v.40 no.1
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    • pp.1-17
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    • 2002
  • The purpose of this study is to examine the possibility of thermal injury to bone tissues during an implant site preparation under the same condition as a typical clinical practice of $Br{\aa}nemark$ implant system. All the burs for $Br{\aa}nemark$ implant system were studied except the round bur The experiments involved 880 drilling cases : 50 cases for each of the 5 steps of NP, 5 steps of RP, and 7 steps of WP, all including srew tap, and 30 cases of 2mm twist drill. For precision drilling, a precision handpiece restraining system was developed (Eungyong Machinery Co., Korea). The system kept the drill parallel to the drilling path and allowed horizontal adjustment of the drill with as little as $1{\mu}m$ increment. The thermocouple insertion hole. that is 0.9mm in diameter and 8mm in depth, was prepared 0.2mm away from the tapping bur the last drilling step. The temperatures due to countersink, pilot drill, and other drills were measured at the surface of the bone, at the depths of 4mm and 8mm respectively. Countersink drilling temperature was measured by attaching the tip of a thermocouple at the rim of the countersink. To assure temperature measurement at the desired depths, 'bent-thermocouples' with their tips of 4 and 8mm bent at $120^{\circ}$ were used. The profiles of temperature variation were recorded continuously at one second interval using a thermometer with memory function (Fluke Co. U.S.A.) and 0.7mm thermocouples (Omega Co., U.S.A.). To simulate typical clinical conditions, 35mm square samples of bovine scapular bone were utilized. The samples were approximately 20mm thick with the cortical thickness on the drilling side ranging from 1 to 2mm. A sample was placed in a container of saline solution so that its lower half is submerged into the solution and the upper half exposed to the room air, which averaged $24.9^{\circ}C$. The temperature of the saline solution was maintained at $36.5^{\circ}C$ using an electric heater (J. O Tech Co., Korea). This experimental condition was similar to that of a patient s opened mouth. The study revealed that a 2mm twist drill required greatest attention. As a guide drill, a twist drill is required to bore through a 'virgin bone,' rather than merely enlarging an already drilled hole as is the case with other drills. This typically generates greater amount of heat. Furthermore, one tends to apply a greater pressure to overcome drilling difficulty, thus producing even greater amount heat. 150 experiments were conducted for 2mm twist drill. For 140 cases, drill pressure of 750g was sufficient, and 10 cases required additional 500 or 100g of drilling pressure. In case of the former. 3 of the 140 cases produced the temperature greater than $47^{\circ}C$, the threshold temperature of degeneration of bone tissue (1983. Eriksson et al.) which is also the reference temperature in this study. In each of the 10 cases requiring extra pressure, the temperature exceeded the reference temperature. More significantly, a surge of heat was observed in each of these cases This observations led to addtional 20 drilling experiments on dense bones. For 10 of these cases, the pressure of 1,250g was applied. For the other 10, 1.750g were applied. In each of these cases, it was also observed that the temperature rose abruptly far above the thresh old temperature of $47^{\circ}C$, sometimes even to 70 or $80^{\circ}C$. It was also observed that the increased drilling pressure influenced the shortening of drilling time more than the rise of drilling temperature. This suggests the desirability of clinically reconsidering application of extra pressures to prevent possible injury to bone tissues. An analysis of these two extra pressure groups of 1,250g and 1,750g revealed that the t-statistics for reduced amount of drilling time due to extra pressure and increased peak temperature due to the same were 10.80 and 2.08 respectively suggesting that drilling time was more influenced than temperature. All the subsequent drillings after the drilling with a 2mm twist drill did not produce excessive heat, i.e. the heat generation is at the same or below the body temperature level. Some of screw tap, pilot, and countersink showed negative correlation coefficients between the generated heat and the drilling time. indicating the more the drilling time, the lower the temperature. The study also revealed that the drilling time was increased as a function of frequency of the use of the drill. Under the drilling pressure of 750g, it was revealed that the drilling time for an old twist drill that has already drilled 40 times was 4.5 times longer than a new drill The measurement was taken for the first 10 drillings of a new drill and 10 drillings of an old drill that has already been used for 40 drillings. 'Test Statistics' of small samples t-test was 3.49, confirming that the used twist drills require longer drilling time than new ones. On the other hand, it was revealed that there was no significant difference in drilling temperature between the new drill and the old twist drill. Finally, the following conclusions were reached from this study : 1 Used drilling bur causes almost no change in drilling temperature but increase in drilling time through 50 drillings under the manufacturer-recommended cooling conditions and the drilling pressure of 750g. 2. The heat that is generated through drilling mattered only in the case of 2mm twist drills, the first drill to be used in bone drilling process for all the other drills there is no significant problem. 3. If the drilling pressure is increased when a 2mm twist drill reaches a dense bone, the temperature rises abruptly even under the manufacturer-recommended cooling conditions. 4. Drilling heat was the highest at the final moment of the drilling process.