• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.599-604
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• 2004

Implantable flexible sensor using polymer/metal multilayer processing technique for telemetrical real-time blood pressure monitoring is presented. The realized sensor is mechanically flexible, which can be less invasively implanted and attached on the outside of blood vessel to monitor the variation of blood pressure. Therefore, unlike conventional detecting methods which install sensor on the inside of vessel, the suggested monitoring method can monitor the relative blood pressure without injuring blood vessel. The major factor of sudden death of adults is a disease of artery like angina pectoris and myocardial infarction. A disease of circulatory system resulted from vessel occlusion by plaque can be preventable and treatable early through continuous blood pressure monitoring. The procedure of suggested new method for monitoring variation of blood pressure is as follows. First, integrated sensor is attached to the outer wall of blood vessel. Second, it detects mechanical contraction and expansion of blood vessel. And then, reader antenna recognizes it using telemetrical method as the relative variation of blood pressure. There are not any active devices in the sensor system; therefore, the transmission of energy and signal depends on the principle of mutual inductance between internal antenna of LC resonator and external antenna of reader. To confirm the feasibility of the sensing mechanism, in vitro experiment using silicone rubber tubing and blood is practiced. First of all, pressure is applied to the silicone tubing which is filled by blood. Then the shift of resonant frequency with the change of applied pressure is measured. The frequency of 2.4 MHz is varied while the applied pressure is changed from 0 to 213.3 kPa. Therefore, the sensitivity of implantable blood pressure is 11.25 kHz/kPa.

• Restorative Dentistry and Endodontics
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• v.36 no.4
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• pp.280-289
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• 2011

Objectives: The purpose of this study was to evaluate ${\mu}TBS$ (microtensile bond strength) of current dentin bonding adhesives which have different hydrophobicity with low-shrinkage silorane resin. Materials and Methods: Thirty-six human third molars were used. Middle dentin was exposed. The teeth were randomly assigned to nine experimental groups: Silorane self-etch adhesives (SS), SS + phosphoric acid etching (SS + pa), Adper easy bond (AE), AE + Silorane system bonding (AE + SSb), Clearfil SE bond (CSE), CSE + SSb, All-Bond 2 (AB2), AB2 + SSb, All-Bond 3 (AB3). After adhesive's were applied, the clinical crowns were restored with Filtek LS (3M ESPE). The 0.8 mm ${\times}$ 0.8 mm sticks were submitted to a tensile load using a Micro Tensile Tester (Bisco Inc.). Water sorption was measured to estimate hydrophobicity adhesives. Results: ${\mu}TBS$ of silorane resin to 5 adhesives: SS, 23.2 MPa; CSE, 19.4 MPa; AB3, 30.3 MPa; AB2 and AE, no bond. Additional layering of SSb: CSE + SSb, 26.2 MPa; AB2 + SSb, 33.9 MPa; AE + SSb, no bond. High value of ${\mu}TBS$ was related to cohesive failure. SS showed the lowest water sorption. AE showed the highest solubility. Conclusions: The hydrophobicity of adhesive increased, and silorane resin bond-strength was also increased. Additional hydrophobic adhesive layer did not increase the bond-strength to silorane resin except AB2 + SSb. All-Bond 3 showed similar ${\mu}TBS$ & water sorption with SS. By these facts, we could reach a conclusion that All-Bond 3 is a competitive adhesive which can replace the Silorane adhesive system.

• Restorative Dentistry and Endodontics
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• v.33 no.4
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• pp.389-396
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• 2008

The purpose of this study was to evaluate the color stability of resin cements with accelerated test. Four dual curing resin cements: Panavia-F (KURARAY). Duolink (BISCO), Variolink-II (Ivoclar Vivadent), and RelyX Unicem (3M ESPE) and 1 self curing resin cement: Resiment CE (j. l. Blosser) were used in this study. In control group, Gradia Anterior (GC) composite resin and Tescera Dentin (Bisco) indirect composite were used. Ten disk shape specimens were made from each resin cement. The specimens were subjected to an accelerated aging process in a refrigerated bath circulator at 60$^{\circ}C$ for 15 and 30 days. Spectrophotometric analyses were made before and after 15 days and 30 days of accelerated aging time. The color characteristics ($L^*,\;a^*,\;b^*$) and the color difference (${\Delta}E^*$) of the specimens before and after immersion were measured and computed. Regardless of type of the resin cements, $L^*$ value was decreased and $a^*$ value was increased, but there were no significant difference. But $b^*$ value was increased significantly (p < 0.05). Tescera inlay showed least color change (p < 0.05), but Gradia showed notable color change after 15 days. After 30 days on accelerated aging, ${\Delta}E^*$ value was increased (Panavia-F < Variolink-II < Resiment CE < Duolink < Unicem) (p < 0.05). but there were no significant difference among Panavia-F, Variolink-II, and Resiment CE groups. After 30 days of accelerated aging, ${\Delta}E^*$ value of all resin cements were greater than 3.0 and could be perceived by the human eye.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.53-68
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• 1998

Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.

• Radiation Oncology Journal
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• v.13 no.4
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• pp.377-383
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• 1995

Purpose : To obtain the optimal treatement method in patients with endometrial carcinoma(clinical stage FIGO I, II) by comparative analysis between preoperative radiotherapy (pre-op RT) and postoperative radiotherapy (post-op RT). Material and Methods : A retrospective review of 62 endometrial carcinoma patients referred to the Yonsei Cancer Center for radiotherapy between 1985 and 1991 was undertaken. Of 62 patients, 19 patients(Stagel : 12 patients. Stagell;7 patients) received pre-op RT before TAH(Total Abdominal Hysterectomy) and BSO (Bilateral Salphingoophorectomy) (Group 1) and 43 patients(Stage 1;32 patients, Stage 2; 11 patients) received post-op RT after TAH and BSO (Group 2). Pre-op irradiation was given 4-6 weeks prior to surgery and post-op RT administered on 4-5 weeks following surgery. All patients except 1 patient(Group 2: ICR alone) received external irradiation. Seventy percent(13/19) of pre-op RT group and 54 percent(23/42) of post-op RT group received external pelvic irradiation and intracavitary radiation therapy(ICR). External radiation dose was 39.6-55 Gy(median 45 Gy) in 5-6. 5weeks through opposed AP/PA fields or 4-field box technique treating daily, five days per week, 180 cGy per fraction. ICR doses were prescribed to point A(20-39.6 Gy, median 39 Gy) in Group 1 and 0.5cm depth from vaginal surface (18-30 Gy,median 21 Gy) in Group 2. Results : The overall 5 year survival rate was $95{\%}$. No survival difference between pre-op and post-op RT group.($89.3{\%}$ vs $97.7{\%}$, p>0.1) There was no survival difference by stage, grade and histology between two groups. The survival rate was not affected by presence of residual tumor of surgical specimen after pre-op RT in Group 1 (p>0.1), but affected by presence of lymph node metastasis in post-op RT group(P<0.5). The complication rate of pre-op RT group was higher than post-op RT. ($16{\%}$ vs $5{\%}$) Conclusion : Post-op radiotherapy offers the advantages of accurate surgical-pathological staging and low complication rate.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.9.2-9
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• 1983

We have observed 74 cases of radiolucent foreign bodies in food and air passage in E. N. T. department of Hang Gang Sacred Hospital, from Jan. 1972 to Mar. 1983. The following results were obtained. 1) Distribution of location was 56 cases(75.6 %) in food passage and 18 cases (24.4 %) in air passage. 2) In age distribution, 46 cases (82.1 %) of F. B. in food passage were found in patient over 21 years old and 12 cases (66.7 %) of F. B. in air passage were found in patient under 5 years old. 3) Female seems to be more frequently involved than male in cases of F. B. of food passage and in cases of air passage, male is more frequent. Food passage male: female - - - 25 : 31 Air passage male: female - - - 10 : 8 4) Meats was the most frequent foreign body in food passage (19 cases-33.9%), and the bony pieces was next (17 cases-30.4 %). Plastic material was the most frequent foreign body in air passage (9 cases-49.9 %), and the vegetable seed was the second (4cases-22.0 %). 5) In the location of F. B. in food passage, the first narrowing of the esophagus was the most frequent site and in air passage, the bronchus-especially right bronchus-was the most frequent site. 6) In the duration of lodgement, 44 cases(78.6 %) of F.B. in food passage were visited with - in 24 hours, and 11 cases (61 %) of F. B. in air passage were visited with - in 24 hours. 7) Simple chest PA was checked in all patient and then, esophagogram was checked in 34 cases of F.B. in food passage, among them positive finding was noticed in 23 cases. 8) Removal of F. B. in food passage by esophagoscopy was performed in 54 cases (96.4 %), but in the cases of air passage, removal of F. B. by bronchoscopy was performed in 14 cases (77.8 %). 9) Complications of food passage by the F. B. itself or esophagoscopy were esophageal mucosal laceration (1 cases-1.8 %) and esophageal perforation (1 case -1. 8 %) and complication of air passage by F. B. itself or bronchoscopy were atelectasis (2 cases -11.1 %) and pneumonia (3 cases-16.7 %).

• the MEAT Journal
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• s.34 winter
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• pp.14-25
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• 2007

The objective of this study was to investigate the physicochemical, microbiological and sensory properties of food additive-free grilled pork products manufactured using loin (T1), tender loin (T2) and ham (T3). The samples were heated for 30 min at $60^\circC$, and then 50 min for $150^\circC$. After cooling, vacuum packaged grilled pork samples was stored at $4\pm$$1^\circC$ for 40 days. The pH values of grilled pork samples ranged from 5.92 (T1) to 6.10 (T3) at the initial storage time, and from 6.28 (T1) to 6.60 (T3) after 40 days. The water holding capacities (%) was 85.99~93.24% for T1, 85.26~93.89% for T2 and 89.11~94.67% for T3, all of which were slightly higher than those of other pork products. The shear force values of T2 were significantly higher (p<0.05) than those of the other pork products throughout the storage period. The TBARS and VBN values of T2 were significantly higher (p<0.05) than those of T1 and T3. With regard to microorganisms, all grilled pork samples was in good condition, showing 1.93~3.48 log10 CFU/g via total plate counts, and 1.74~3.48 log10 CFU/g for lactic acid bacteria throughout the storage period. Regarding sensory evaluation, the scores of overall acceptability in all products were above 5.0 points through 40 days of storage.

• The korean journal of orthodontics
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• v.30 no.3 s.80
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• pp.367-375
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• 2000

If a mandibular prognathic patient has an extremely unnatural anteroposterior and vertical maxilla or keen esthetical perception for facial profile, orthognathic surgery must be performed along with orthodontic treatment, which alone cannot provide satisfactory results in this case. Esthetical improvement becomes an important factor in the satisfaction level of the patient's treatment result, but an attempt to objectively measure beauty holds many problems. Therefore, in the end, the patient submits the final esthetical evaluation based on his/her subjective viewpoint. Because Korean people have a tendency to prefer the facial appeareance of westerners, they favor an oval shaped face over the traditional round face. This research was conducted in response to the complaints raised by patients who claim that their face had become more round from widening of facial width after the orthognathic surgery for manidibular prognathism than before the surgery. The following results were obtained on the changes in facial appearance and patient satisfaction level by analyzing the skull P-A analysis of total of 14 patients (8 male and 6 female) who underwent orthognathic surgery primarily chief complaint for manidibular prognathism and from their responses on questionnaires. These results are to be used in the research on the pre- and post- operative changes in facial height and width from orthognatic surgery. 1. Three ($21.4\%$) of 14 patients said that their face had widened. 2. The A group showed no change in mandibular width but B group showed a 0.7mm reduction. The facial width increased by 0.45mm and 0.66mm in groups A and B, respectively, after the orthognathic surgery 3. After the surgery the facial length changed by an 0.52mm increase in upper facial height , 1.19mm reduction in lower facial height, and 0.7mm reduction in mandibular height in group A. In group B group, there was a 0.67mm reduction in upper facial height, 3.66mm reduction in lower facial height, and 5mm reduction in mandibular height. 4. In reference to facial width, the facial height showed $1.5\%$ reduction in group A and $3.6\%$ reduction in group B after the surgery. 5. In reference mandibular height-to-facial width ratio, there was a $1.3\%$ reduction in group A, and $4.4\%$ reduction in group B after the surgery. 6. In reference to the mandibular height-to-width ratio, there was a $1.3\%$ reduction in group A and $4.3\%$ reduction in group B after the surgery. 7. Although the change in the facial width due to surgery can be ignored, sufficient explanation should be Provided to the patient before surgery on the fact that the face can appear to be relatively wide because of the reduced facial length as result of the surgery.

• Journal of the Korea Concrete Institute
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• v.18 no.6 s.96
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• pp.811-817
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• 2006

The primary purpose of this study is to estimate the guaranteed strength and construction quality of the combined high flowing concrete which is used in the slurry wall of underground LNG storage tank. The required compressive strength of this type of concrete become generally known as a non economical value because it is applied the high addition factor for variation coefficients and low reduction factor under water concrete. Therefore, after estimation of the construction quality and guaranteed strength in actual site work, this study is to propose a suitable equation to calculate the required compressive strength in order to improve its difference. Application results in actual site work are shown as followings. The optimum nix design proportion is selected that has water-cement ratio 51%, sand-aggregate ratio 48.8%, and replacement ratio 42.6% of lime stone powder by cement weight. Test results of slump flow as construction quality give average 616~634mm. 500mm flowing time and air content are satisfied with specifications in the rage of 6.3 seconds and 4.0% respectively. Results of strength test by standard curing mold show that average compressive strength is 49.9MPa, standard deviation and variation coefficients are low as 1.66MPa and 3.36%. Also test results by cored cylinder show that average compressive strength is 66.4MPa, standard deviation and variation coefficients are low as 3.64MPa and 5.48%. The guaranteed strength ratio between standard curing mold and cored cylinder show 1.23 and 1.32 in the flanks. It is shown that applied addition factor for variation coefficients and reduction factor under water concrete to calculate the required compressive strength is proved very conservative. Therefore, based on these results, it is proposed new equation having variation coefficients 7%, addition factor 1.13 and reduction factor 0.98 under water connote.

• Tuberculosis and Respiratory Diseases
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• v.51 no.4
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• pp.334-345
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• 2001

Background : Pulmonary tuberculosis(TB) is still prevalent and remains a significant clinical problem for the elderly. However, the disease presents in many ways, and there are frequent adverse drug reactions that may prevent the early diagnosis and treatment of elderly TB patients compared to the young. The purpose of this study was to determine whether or not there are any differences in the clinical feature of pulmonary tuberculosis(TB) in both the diagnosis and treatment between the young (less than 64 years) and the elderly (65 years and more). Methods : The medical records of 125 young and 70 elderly pulmonary TB patients, who were diagnosed with and treated for pulmonary TB at the Seoul Municipal Boramae Hospital from November 1991 to January 1997, were analyzed retrospectively. Results : Anorexia(12% vs. 31.4%), general weakness (20.0% vs. 54.3%), dyspnea(21.6% vs. 37.1%) and an abnormal mentality (0.8% vs. 15.7%) were more frequent presenting symptoms in elderly TB patients, whereas hemoptysis (32.8% vs. 10.0%) and fever (BT > $37^{\circ}C$, 58.4% vs. 35.7%) were more frequent in the young. The elderly had a higher number of cardiovascular and chronic obstructive pulmonary diseases as underlying illnesses. In chest PA, there were no differences in the location of the TB lesion, but the appearances were initially diagnosed more frequently as pneumonia or lung cancer (8.8% vs. 30.0%, p<0.05) in the elderly. There was no difference in the detection rate of acid fast bacilli(AFB) in the sputum between the two groups. There were no differences in the treatment response and follow-up loss. However, adverse drug reactions (13.6% vs. 45.7%, p<0.05), and changes in medication (4.9% vs. 25.7%, p<0.05) during treatment occurred more frequently in the elderly. One among the 125 young patients died from tuberculosis whereas 6 among the 70 elderly patients died from the disease. Conclusion : Because the clinical and radiological presentations were more atypical, a sputum AFB smear and culture should be done immediately in the elderly who are TB. The elderly experienced more frequent adverse drug reactions and mortality during treatment, but the response to treatment was good and rapid.