• Restorative Dentistry and Endodontics
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• v.32 no.6
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• pp.522-529
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• 2007

The purpose of this study was to compare the apical leakage of the root canal filled with the System B and the EndoTwinn(the combined application of heat and ultrasonic vibration). Sixty extracted premolars with straight root were cleaned and shaped to size 35. Group SB was obturated using System B and Group ET was filled with EndoTwinn. A size 35 of 0.06 tapered gutta-percha and Adseal were used and the plugger which could be introduced to 4 mm short of working length was selected in the obturation procedure. As the positive control, Group PC was not filled. In Group SB, ET and PC, all external surfaces of each tooth were coated with nail varnish leaving only 1 mm area around the apical foramen. In the negative control of Group NSB and Group NET, all of external tooth surface including apical foramen was coated with the nail varnish. The specimens were immersed in methylene blue dye solution for 2 days. Then the specimens were sectioned at each 1 mm from apex to 5 mm level. The final score of one specimen was given by summing up of the points at all levels. The dye leakage of Group ET was significantly less than that observed in Group SB (p < 0.05). And the frequency of gutta-percha pulling out from root canal when the plugger was removed was more often with the System B than with EndoTwinn but there was no significant difference.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.166-172
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• 2001

In order to increase ginsenoside content, to reduce chemical change, to shorten extracting procedure, new methods of extraction and fractionation of crude ginseng saponin were established and compared for their chemical composition. Those are hot MeOH extraction/n-BuOH fractionation (BuOH method) and hot MeOH extraction/Diaion HP-20 adsorption/MeOH elution (HP-20 method), which are already known methods, and additional three new methods: hot MeOH extraction/cation AG 50W $adsorption/H_2O$ elution/n-BuOH extraction (AG 50W method), cool MeOH extraction/Diaion HP-20 adsorption/MeOH elution (cool extraction method) and direct extraction with EtOAc/n-BuOH (direct extraction method). AG 50W method provided a crude saponin showing the highest content of ginsenosides of 61.5% and the lowest contents of protein and free amino acids of 0.93% and 0.19%, respectively. The protein content was the highest as 14.18% in the crude saponin by HP-20 method, while free sugar content was the highest as 13.5% by BuOH method, indicating that these are factors that lower the rate of ginsenoside in crude saponins by those methods. On the other hand, it was revealed that AG 50W method produced large amount of prosapogenins during the pass through the cation exchange resin (AG 50W) column being strongly acidic. Crude saponin from direct extraction method showed relatively higher composition of ginsenoside $Rg_1$ and Re. The results suggest that contents and composition of ginsenosides and other chemical components in crude ginseng saponin greatly depend on the condition of the extraction and fractionation.

• Geophysics and Geophysical Exploration
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• v.9 no.4
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• pp.279-290
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• 2006

The borehole radar methods used to tunnel detection are mainly classified into borehole radar reflection, directional antenna, crosshole scanning, and radar tomography methods. In this study, we have investigated the feasibility and limitation of each method to tunnel detection through case studies. In the borehole radar reflection data, there were much more clear diffraction signals of the upper wings than lower wings of the hyperbolas reflected from the tunnel, and their upper and lower wings were spreaded out to more than 10m higher and lower traces from the peaks of the hyperbolas. As the ratio of borehole diameter to antenna length increases, the ringing gets stronger on the data due to the increase in the impedance mismatching between antennas and water in the boreholes. It is also found that the reflection signals from the tunnel could be enhanced using the optimal offset distance between transmitter and receiver antennas. Nevertheless, the borehole radar reflection data could not provide directional information of the reflectors in the subsurface. Direction finding antenna system had a advantage to take a three dimensional location of a tunnel with only one borehole survey even though the cost is still very high and it required very high expertise. The data from crosshole scanning could be a good indicator for tunnel detection and it could give more reliable result when the borehole radar reflection survey is carried out together. The images of the subsurface also can be reconstructed using travel time tomography which could provide the physical property of the medium and would be effective for imaging the underground structure such as tunnels. Based on the results described above, we suggest a cost-effective field procedure for detection of a tunnel using borehole radar techniques; borehole radar reflection survey using dipole antenna can firstly be applied to pick up anomalous regions within the borehole, and crosshole scanning or reflection survey using directional antenna can then be applied only to the anomalous regions to detect the tunnel.

• Journal of Acupuncture Research
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• v.22 no.3
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• pp.123-135
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• 2005

Objective : The aim of this study was to rivew systemically literature and clinical trials in the treatment of urinary incontinence or lower urinary tract syndrome(LUTS). Methods : Computerized literature searches were carried out on two electronic database, and computerized searching on some korea oriental medicine journals in library of Kyung-Hee Medical center. Results : 1. Three reports of review study, six reports of experimental study and fourteen reports of clinical trials were collected and reviewed. Three reports of review study were all printed in the korea oriental medicine journal. From 2000, researches and studies have been increased in quantity and improved in quality. 2. Urinary disturbance include variable symptoms of lower urinary tract symptoms, urinary incontinence, in theaspect of Oriental medicine these symptoms are anurin, dysuria, urinary incontinence, nochumal enuresis, uracratia and so on. 3. Roughly physiological procedure of Acupuncture in Treatment of Urianry Disturbance may be that effect of acupuncture stimulation for parasympathetic nerve, sleep-arousal system in cerebrum, pontine/spinal urination center and pudendal/pelvic nerve affect bladder in expansion of bladder capacity, inhibition of urinary contraction and affection in periurethral muscle by continuous excitement of spinal annular circuit and synapse of neuron. 4. Clinical result for acupuncture treatment in urinary disturbance is summarized that acupuncture treatment in urianation disturbance of Neurogenic Bladder, Incontinence, Cycitis, Nocturnal Enuresis, Prostatitis/Pelvic Pain Syndrom and so on is significant clinical trials and technique. Conclusion : Hereafter, in the old age society these variable urinary disturbance patients are increased and desire of treatment may be also increased. So study of various and formal treatment and tecnnique is needed.

• Journal of Korean Public Health Nursing
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• v.1 no.1
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• pp.45-61
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• 1987

This Study was an attempt to estimate the optimum numbers of Operating Room Nursing Manpower by measuring the amount of service hours required by the patients in Operating Room in relation to the service amount actually provided by the nurses. The major concern of this study was placed on the measurement of Nursing Service Requirements by using the Operating Room (O. R) Patient Acuity System recently developed by M. M. Hart to classify the O. R. patients into four groups according to the degree of the complexity of operative procedure and some other elements which increase nursing activities in respect of patient care; Acuity IV group is the one requires nursing services most, on the other hand Acuity I requires least. nu sing The objectives of this study were as follows; 1. To analyze functions of the nursing personnel in O. R. by time unit and to estimate the average time a nurse can activate for productive functions. 2. To measure the actual amount of nursing times provided by nurses to the surgical patients. 3. To develop a patient classification system in order to measure the amount of Nursing services required by the patients. 4. To calculate an appropriate number of nursing manpower to meet the needs of the patients. In order to conduct the research both selected nurses and patients in 'S' University Hospital were Studied by utilizing the O. R. Patient Acuity System as well as the Classification Chart developed by Association of Operating Room Nurses (A. O. R. N) as a means of classifying functions of O. R. nurses. That is; Functions of the 10 selected O. R. nurses observed during the period of June 30 to July 4, 1986, whereas the amount of nursing services required by or provided to the 974 patients who had received surgeries during the period of June 9 to July 4, 1986. The results of this study were as follows; 1) The actual working hours per a nurse averaged 6.7 hours a day. 2) Each nurse's daily routine schedule consists of $71.4\%$ for Technical Functions, $16.1\%$ for Nonprodective Functions, $6.6\%$ for Assessment and Evaluation, $3.9\%$ for Overseeing and Supervision and the rest $2.0\%$ for Patient Preparation respectively. 3) Preoperative waiting time per a patient was 24.1 minutes on the average; for the first case was 10.7 minutes, whereas for the following cases was 32.0 minutes. 4) Total Operation time for the 974 patients during the period of observation for this study amounted to 2759.6 hours, weekly hour was equivalent to 689.9 hours, Whereas daily operation time averaged 130 hours. Meanwhile the average operation time per patient was 2.8 hours ; for the case of Acuity IV was 5.6 hours, 5. 1 hours for the case of Acuity III, 2.3 hours for Acuity II and 1.1 hours for Acuity I. 5) According to the O. R. Patient Acuity System, $64.5\%$ of the whole patients belonged to Acuity II, $23.7\%$ to Acuity III, 11. $3\%$ to Acuity IV and $0.7\%$ to Acuity I respectively. 6) Required amount of nursing times based on the preoperative waiting time and operation time was 7167.8 person hours, which showed that $5.5\%$ of them needed for preoperative nursing care, whereas the rest $94.5\%$ for intraoperative nursing care. In terms of the O. R. Patient Acuity System, $49.7\%$ of total nursing service requirements was needed for Acuity II patients, $27.4\%$ for Acuity III patients, $17.2\%$ for Acuity IV patients and $0.2\%$ for Acuity I patients. 7) The rate of the nursing services provided against the required nursing times was about $81.4\%$ on the average; some departments, like those of Plastic Surgery, Otolaryngology and Ophthalmology whose patients mostly belonged to Acuity II recorded hegher provision rate than average, whereas other departments of Thoracic Surgery. Neurosurgery and Orthopedic Surgery whose patients belonged to Acuity III and Acuity IV as well as Acuity II recorded lower provision rate than average. 8) Subsequently, required numbers of nursing manpower was 10.7 nurses additionally. Based on the above findings the following recommendations will be made; 1) this study recommends, develops. and adopts an accurate and realistic O. R. Patient Acuity System which can help measure the nursing service requirements objectively to elicit the rationales of allocation of nursing personnels. 2) this study proposes storongly place nurses who take the role of preoperative nursing care exclusively for the waiting patients in O. R. and shortening their waiting time by close communication between the designated O. R. and the ward.

• Journal of Technologic Dentistry
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• v.21 no.1
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• pp.27-41
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• 1999

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-30Pd-10Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electric furnace and centrifugal casting machine in Ar atmosphere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at 350-$550^{\circ}C$ Age-hardening characteristic of the small Au-containing Ag-Pd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, energy dispersed spectra and electron probe microanalysis. Principal results are as follows ; Maximum hardening occured in two co-phases of ${\alpha}_2$ + PdCu In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase($L1_o$ type) and an Ag-rich ${\alpha}_2$ phase occurred and a discontinuous precipitation occurred at the grain boundary. From the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu redered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}{\to}{\alpha}_1+PdCu{\to}{\alpha}_2+PdCu$ at Pd/Cu = 3 Pd element of Ag-Pd-Cu alloy is more effective dental alloy on anti-corrosion and is suitable to isothermal ageing at $450^{\circ}C$.

• Journal of Technologic Dentistry
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• v.19 no.1
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• pp.21-35
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• 1997

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy is cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-20Pd-20Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electic furace and centrifugal casting machine in Ar atmoshpere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age-hardening characteristics of the small Au-containing Ag-pPd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, emergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, I. e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the Llo type face centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affedted by the Cu concentration. In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase(L1o type) and an Agrich ${\alpha}2$ phase occurred and a discontiunous precipitation occurred at the grain boundary. Form the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}\to{\alpha}+{\alpha}2+PdCu\to{\alpha}1+{\alpha}2+PdCu$ at Pd/Cu = 1 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.8-17
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• 2000

The BER performance and the capacity variation of a microcell due to power control error(PCE) is analyzed on service types(data and voice, respectively) for the reverse link of an overlaid cell CDMA system. The procedure of analysis is followed as: First, we calculate BER performance according to PCE. Next, we find the minimum SNR for voice service, BER=TEX>$10^{-3}$, and data service, BER=TEX>$10^{-5}$. Then, according to the calculated SNR, we find the maximum capacity of a microcell and macrocell and the capacity of a microcell where interference is considered is found and analyzed with that in perfect power control. We get to the results as follows. The BER performance in 1 dB PCE is similar to that in perfect power control, however, with a increase in PCE, the BER performance is largely degraded. In terms of capacity, it is shown that if the PCE is equal or less than 2 dB, the effect of the PCE on voice service is more than that on data service, but if the PCE is equal or more than 3 dB, effect of the PCE on data service is more than that on voice. Besides, if the PCE is equal or less than 2 dB, both PCE and interference should be considered to calculate the capacity of a microcell, but if the PCE is equal or more than 3 dB, interference can be negligible since the effect of PCE is much stronger than that of interference. Therefore, the microcell should be located where $R_d$, the ratio of a microcell to a macrocell radius, is equal to 0.1, and d, the ratio of the distance between a microcell and a macrocell to the macrocell radius, is equal or more than 0.5, in order to obtain a appropriate microcell capacity against interference. If $\sigma$ is adjusted to less than 2 dB, we may get equal or more than 70% of the maximum microcell capacity.

• The korean journal of orthodontics
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• v.26 no.2 s.55
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• pp.153-162
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• 1996

Rapid maxillary expansion is widely used for the correction of anteroposterior discrepancies, constriction of the maxillary arch, etc. This experiment was undertaken to examine the serial changes in the osteogenesis as well as the collagen fiber bundles in the intermaxillary suture during the rapid maxillary expansion treatment. Four young female dogs aged 6 to 8 months old and not showing menarche yet were used for the experiment. The maxillary impression of dogs were taken, expansion device cast and Hyrax screw soldered at the midline in the 1st premolar area. RME device was delivered to the dogs and the activation of 0.25 mm per quarter-turn was done 2 times per day for 10 days until 5 mm separation was made. Separation of the maxilla was confirmed by X-ray. The animals were sacrificed on 0, 15, 30, 60 days from the finish of maxillary separation and preparations for light microscopy and surface electron microscopy were made. The sutures were cut into frontal serial sections for examination of the histological reactions. The following results were obtained and the conclusions made. 1. The edges of the two palatal plates bordering the midpalatal suture which at the beginning of the retention period were mainly composed of compact bone, underwent extensive resorption followed by new bone formation and gradually became spongy bone rich in bone marrow which in the 60 day retention animal became the compact bone with short intermaxillary suture space. During this transformation, newly formed trabecular bone tissues were added to the original margin. 2. Throughout the expansion period, the collagen fibers underwent successive changes such as stretching, loss of polarity, and finally fibrillogenesis. Towards the end of the expansion procedure, sharpey's fiber formation in newly formed bones were observed. 3. Bony spicules were found in the initial stage of retention on occlusal topographic X-rays, which later were confirmed to have ossified. 4. Judging from the histological changes occuring during the experimental expansion, excessive expansion will cause an excessive bleeding, and retard the remodeling of intermaxillary suture. According to the above results, the bone remodeling after rapid maxillary expansion was preceded by the migration of migratory cells into the intermaxillary suture area. The bone remodeling phenomena were on-going during the 2 months retention sample.

• Journal of Oral Medicine and Pain
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• v.32 no.2
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• pp.177-185
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• 2007

Iatrogenic injury following dental treatments and the use of local anesthetics may cause taste disorders. The aims of this study were to investigate quantitative and qualitative changes of taste due to unilateral inferior alveolar nerve block anesthesia and further to evaluate potential effects on taste function related to anesthesia or hypoesthesia of inferior alveolar nerve, possibly occurring after dental procedure. 30 healthy volunteers in their twenties participated in this study (male to female = 1:1, mean age of $24.0{\pm}1.8$ years). Each subject received inferior alveolar nerve block anesthesia on his or her right side with 2% lidocaine HCl containing 1:100,000 epinephrine. Before and after anesthesia, electrogustometric test and chemical localized test for salty, sweet, sour and bitter tastes were performed on the eight sites in the oral cavity; right and left anterior and lateral tongue and circumvallate papilla of the tongue and soft palate. Unilateral inferior alveolar nerve anesthesia produced elevation of electrical taste threshold and reduction of intensity ratings for all 4 tastes (salty, sweet, sour and bitter) over anterior and lateral tongue and circumvallate papilla on the ipsilateral side (p<0.05). Contralateral sides exhibited decreased intensity ratings for salty and sweet taste (p<0.05) on anterior and lateral tongue while there was no significant difference in electrogustometric testing. Based on the results of this study, it is assumed that unilateral local anesthesia on inferior alveolar nerve can affect chorda tympani and glossopharyngeal nerves on the same side, leading to taste deficits. Taste intensity on the contralateral side may, in part, be deteriorated as well.