성인성 치주질환에서 미노클린 국소송달제 효과에 대한 연구

최성호,현석주,구현서,서종진,조규성,채중규,김종관,Choi, Seong-Ho,Hyun, Suk-Ju,Koo, Hyun-Seo,Suh, Jong-Jin,Cho, Kyoo-Sung,Chai, Jung-Kui,Kim, Chong-Kwan 대한치주과학회 1998 Journal of Periodontal & Implant Science Vol.28 No.2

20 Subjects with clinical diagnosis of adult periodontitis with sites having average pocket depth of 4mm were selected for the study. After scaling and root planing of those sites, 30% minocycline-HCI contained in biodegradable device were inserted in one group, scaling and root planing was carried out in another group and the last group was without any periodontal treatment. the difference between the group was detemined by pocket dept, bleeding on prbing, attachment level, distribution of subgingval plaque bacteria. Conclusion was made for the comparisons between baseline and 4 week and the groups. 1. In analysis of pocket depth, there was significant sifference in scaling and root planing group only. 2. Both the scaling and root planing group and minocycline group showed significant decrease in bleeding on probing. 3. There was significant increase in the attachment level in scaling and root planing group, but no difference was foundbetween the groups. 4. There was significant decrease in the total number of subgingival bacteria in all groups and the number of motile bacteria decreased significantly in the minocycline group. These result indicate that insertion of Minocycline-HCI at the base of periodntal pocket was useful as an additional aid of mechanical trarment at the point of periodontal pocket, bleeding on probing, attachment level, microbial distribution.

Dura meter가 성겹 3급 분지부 병소에 미치는 영향

최성호,김준일,문익상,조규성,채중규,김종관,Choi, Sung-Ho,Kim, Joon-Il,Moon, Ik-Sang,Cho, Kyoo-Sung,Chai, Jung-Kyu,Kim, Chong-Kwan 대한치주과학회 1996 Journal of Periodontal & Implant Science Vol.26 No.3

The present study evaluates the effects of dura mater barrier membranes In class III furcation defects on the regeneration of periodontal tissues in dogs. Experimental class III furcation defects were created surgically by removing alveolar bone horizontally down to 4mm from CEJ in mandibular premolars of adult dogs. Dura mater barrier membranes were applied bucco-lingually in the test group, and flap surgery only with no membranes in the control group. The healing was evaluated clinically and histologically after 8weeks. Clinically, the test group showed slight exposures of the membranes, while the control group showed no furcation exposure, The test specimens showed new bone formation coronal to the notch, while the control specimens had new bone formation up to the level of the notch. New cementum was observed in both groups. The test specimens showed functional arrangements of connective tissue fibers between new bone and new cenentum, while irregular arrangements were observed in the controls. No root resorption or ankylosis were observed in either groups,These results suggest that dura mater resorbable barrier membranes on class III furcation defects may be effective in regeneration of alveolar bone and peridontal ligament.

소방항공대의 최적 운영을 위한 개선방안 연구

최성호,최연철,지용선,이영종,김동용,Choi, Sung-Ho,Choi, Yeon-Chul,Ji, Yong-Sun,Lee, Young-Jong,Kim, Dong-Yong 한국항공운항학회 2015 한국항공운항학회지 Vol.23 No.1

Recently, even though firefighting operations are supposed to be incorporated into single body IAW restructuring of the government organizations, in terms of efficiency it is still difficult to find any significant improvements due to the centrally and locally segregated operating bodies and also, as with organizations firefighting manpowers are divided nationally and locally, which results in differing firefighting functioning. Although governments firefighting bodies are changed to operate better, there are always limitations in firefighting operations. This study explores firefighting organizations, manpower, equipment and operations itself to optimize firefighting operations, and ultimately, to provide the future-oriented functions and roles of the firefighting aviation corps.

단말기 보조금이 소비자 편익에 미치는 영향 분석

최성호,한성수,안지영,Choi, Sung-Ho,Han, Sung-Soo,Ahn, Ji-Young 한국통신학회 2005 韓國通信學會論文誌 Vol.30 No.10B

In the mobile telecommunication industry, the effects of handset subsidies are revealed as two aspects. There are the activation of service and handset market and the acceleration of related technology development in the desirable aspect. On the other hand, the rise in service rates and the squandering of the related resources in the undesirable one. There have been a lot of researches that disclose the desirable or undesirable factors through the qualitative methods. However, the quantitative studies are rare. In this study, we consider the positive, from the increase of demand, and negative, from the increase of service rates, effects on consumers' benefit attendant handset subsidies. Then, we quantitatively compared between the positive and negative effects and analyze the direct effects of consumers' benefit of handset subsidies, and figured out that the direct effect is not expected to be positive. 이동통신산업에서 단말기보조금의 효과는 이동통신서비스와 단말기 시장의 활성화와 관련 기술개발의 촉진 등과 같은 긍정적인 효과와 서비스 요금의 상승, 과도한 자원의 낭비, 유효경쟁에 미치는 악영향 등의 부정적인 효과를 동시에 가진다. 이러한 이유로 단말기보조금에 시행에 관한 수많은 논란이 계속되고 있고, 특히 새로운 형태의 이동통신서비스의 시작을 앞두고 있는 근래에는 단말기보조금의 재시행을 두고 그 논란이 더욱 증대되고 있다. 이를 반영하듯 그 동안 많은 연구들이 단말기보조금이 관련 산업 및 사회후생에 미치는 효과를 분석하여 왔다. 그러나 이러한 연구들의 대부분은 단말기보조금의 영향 요소를 파악하고 이에 대한 정성적인 분석에 중점을 두고 있었기 때문에 단말기보조금의 효과에 대한 정량적인 연구를 위한 노력은 지극히 부족한 실정이다. 본 연구에서는 단말기보조금 시행의 직접적인 영향을 받는 소비자 수요증가로 인한 정의 효과와 지급되는 보조금 보전을 위한 이용요금의 인상 등으로 인한 부의 효과를 계량적으로 비교함으로써 과연 단말기 보조금의 직접적인 효과가 소비자 편익에 어느 정도의 영향을 주고 있는지를 분석하여 현 단계에서 그 효과가 긍정적이라고 기대하기 어렵다는 결론을 얻었다.

수종의 조직 양화재에서 탄성 변형과 복원에 관한 연구

최성호,심준성,문홍석,정문규,Choi Sung-Ho,Shim June-Sung,Moon Hong-Seok,Chung Moon-Kyu 대한치과보철학회 2003 대한치과보철학회지 Vol.41 No.1

The dimensional stability of tissue conditioners characterizes the ability of the materials to yield accurate functional impressions of oral mucosa. This study evaluated the viscoelastic property and the linear dimensional changes with the factor of time and thickness of tissue conditioners ($COE-COMFORT^{TM}$, Visco-gel. $COE-SOFT^{TM}$, Soft-Liner). The thickness of these materials were changed (1.5mm, 3.0mm) and the percentage changes in dimension were measured at 1h, 12h, 24h, 36h, 3day, 7day after specimen preparation. From the results large differences appear between the various tissue conditioners. The results suggest that the period recommended for forming functional impression would be 2-3days after insertion in the mouth. in addition. it is important to select tissue conditioners suitable for functional impression because of the wide range of dimensional stability among the materials.

성견 열개형 수평 결손부에서 Calcium Sulfate 차단막이 치주조직 치유에 미치는 영향

최성호,조규성,문익상,채중규,김종관,Choi, Seong-Ho,Cho, Kyu-Sung,Moon, Ik-Sang,Chai, Jung-Kyu,Kim, Jong-Kwan 대한치주과학회 1997 Journal of Periodontal & Implant Science Vol.27 No.1

The present study investigates the effects of calcium sulfate graft on the periodontal healing in intrabony periodontal defects of dogs. Following the general anesthesia with 30mg/kg pentobarbital injected intravenously, the first premolar was extracted and full-thickness periodontal flap was elevated from the second premolar to the fourth premolar. The portion of premolars coronal to the alveolar crest was removed and mesial and distal roots were separated. Exposed root canals were sealed with Caviton and covered completely with flaps sutured. Following the healing period of 12 weeks, the surgical sited were uncovered and $4{\times}4mm$ intrabony defects were surgically created. Those defects with calcium sulfate graft following the root planing was designated as the test sites and those with flap surgery-only were designated as control sites. The animals were sacrificed after 8 weeks and the healing was histologically analyzed. The results were as follows. 1. No foreign body reaction or inflammation were observed in either groups. Calcium sulfate was completely resorbed in the test sites. 2. New cementum was observed coronal to the notch in both groups. Connective tissue fibers were oriented parallel to the root surface in the controls. Connective tissues were formed in large amount in the sites. 3. Test sites showed marked amount of new bone formation while the control sites showed minimal bone gain. 4. Root resorption was observed in coronal portions of th control Sites. The results suggest that calcium sulfate is a biocompatible graft material with a potential for new bone and cementum formation.

가변 스펙트럼 할당을 지원하는 광대역 전력 증폭기를 위한 디지털 전치왜곡기

최성호,서성원,마백일,정의림,Choi, Sung-Ho,Seo, Sung-Won,Mah, Bak-Il,Jeong, Eui-Rim 한국정보통신학회 2011 한국정보통신학회논문지 Vol.15 No.2

인지통신(cognitive radio)과 같이 가변 스펙트럼 할당이 필요한 시스템을 위한 새로운 전치왜곡기를 제안한다. 본 논문에서 고려하는 시스템 모델에서 신호는 한 순간에는 작은 대역폭을 차지하지만 그 중심 주파수가 시간에 따라 변화할 수 있는 상황을 가정한다. 이러한 시나리오에서는 전력 증폭기 출력 단에 위치하는 종단 필터로는 전력증폭기에 의한 하모닉을 제거하지 못하는 상황이 발생할 수 있다. 제안된 전치왜곡기는 기본 주파수 (${\omega}_0$) 신호의 비선형 왜곡을 선형화할 뿐만 아니라, $2{\omega}_0$, $3{\omega}_0$, ...에서 발생하는 하모닉도 동시에 제거한다. 제안된 전치왜곡기는 ${\omega}_0$ 주파수의 정수배에 대응하는 여러 개의 전치왜곡기가 결합된 구조를 가지고 있다. 기본 주파수 ${\omega}_0$에 해당하는 전치왜곡기는 기본 주파수 신호의 선형화를 담당하며, 나머지 주파수에 대응하는 전치왜곡기는 하모닉을 제거하는 역할을 담당한다. 제안된 전치왜곡기에서 필요한 변수는 최소 평균 자승 에러 알고리즘에 의해 동시에 계산되며, 모의실험 결과에 따르면 제안된 방법을 이용하면 기본 주파수의 스펙트럼에 발생하는 스펙트럼 왜곡이 20dB 감소하며, 2차 및 3차 하모닉도 기본 신호의 전력대비 약 -70dB로 작아지는 것을 확인할 수 있다. A new predistortion technique for dynamic spectrum allocation systems such as cognitive radio (CR) is proposed. The system model considered in this paper occupies a small band at a time, but the center frequency can be changed in the wide range of frequency. In this scenario. the front-end filter may not eliminate the harmonics of the power amplifier (PA) output. The proposed PD reduces the spectral regrowth of the fundamental signal at the carrier frequency (${\omega}_0$) and removes the harmonics ($2{\omega}_0$, $3{\omega}_0$, ...) at the same time. The proposed PD structure is composed of multiple predistorters (PDs) centered at integer multiples of ${\omega}_0$. The PD at ${\omega}_0$ is for removing spectral regrowth of the fundamental signal, and the others are for harmonic reduction. In the proposed PD structure, parameters of PDs are found jointly. Simulation results show that the spectral regrowth can be reduced by 20dB, and the 2nd and 3rd harmonics can be reduced down to -70dB from the power of the fundamental signal.

성견 3급 분지부 병소에서 Dura mater와 $Guidor^{(R)}$사용후 치주조직 치유의 비교 연구

최성호,구현서,정현철,조규성,채중규,김종관,Choi, Seong-Ho,Koo, Hyun-Seo,Jung, Hyun-Chul,Cho, Kyoo-Sung,Chai, Jung-Kiu,Kim, Chong-Kwan 대한치주과학회 1997 Journal of Periodontal & Implant Science Vol.27 No.3

There are various treatment methods including barrier membranes in attaining periodontal regeneration and regaining the function of destructed periodontal tissues due to periodontal disease. Barrier membranes consist of non-Resorbable and resorbable types such as Dura mater and $Guidor^{(R)}$ used in the treatment of intrabony defects and classII furcation defects have been shown to be effectively increased the amount of new bone and cementum.In our study we used premolars with class III furcation defects created by removing the bone 4mm apically from CEJ in adult dogs and placed resorbable membrane Dura mater and $Guidor^{(R)}$ for the test group and flap operation was carried out for the control groups. The effect of membrane on junctional epithelium, alveloar bone, cementum, and gingival connective tisssue in the regeneration and healing potential of periodontal tissues was evaluated and healing results were evaluated histologically and histometrically 8 weeks following the surgical procedure. 1. In the clinical observation, there was no exposure of furcation defects in the control group, whereas slight membrane exposure was noted in the test group. 2. New bone was formed up to the level of the notch in the control group, whereas in the test group new bone formation was observed above the level of the notch. 3. New cementum was formed in both groups of the experiment. 4. The connective tissue observed between the new cementum and new bone in the test group were functionally orientated, compared to the irregular formation of connective tissues found in the control group. 5. Root resorption or ankylosis was not observed in any of the groups 6. The mean and median of the control group were 4.31% and 2.23% and for the Dura mater group were 27.85% and 15.57% respectively. There was no significant difference between Dura mater and the control group. 7. The mean and median of the control group were 4.31% and 2.23% and for the $Guidor^{(R)}$ group were 37.27% and 37.19% respectively. There was a significant difference in these two groups(P<O.05). 8. The mean and median of the Dura mater group were 27.85% and 15.57% and for the $Guidor^{(R)}$ were 37.27% and 37.19%. There was no significant difference between the two test groups. Thus, by using Dura mater and Guidor in classIII furcation defects, the predictable amount of periodontal ligament and alveolar bone regeneration may result.

영아기에 시행한 단일 또는 임시 이중인공수정체삽입술 후 굴절력 변화 및 합병증 비교 연구

최성호,정태영,정의상,Sung-Ho Choi,Tae-Young Chung,Eui-Sang Chung 대한안과학회 2005 대한안과학회지 Vol.46 No.4

Purpose: The purpose of this study was to assess the incidence of postoperative complications and the change of refractive error in infantile eyes after cataract surgery and single intraocular lens(IOL) or temporary piggyback IOL implantation. Methods: Eight consecutive patients (13 eyes) who underwent IOL implantation under 12 months of age between 1999 and 2002 were enrolled. Eight eyes of 6 patients had a single IOL implanted and the other 5 eyes of 3 patients underwent temporary piggyback IOL implantations. A retrospective chart review was conducted. Results: The mean age at surgery was 6.1 months. The mean follow-up period was 10 months. The average postoperative refraction at one week was +7.82D after single IOL and +0.32D after piggyback IOL. The average postoperative refraction at last follow-up was +4.25D and -3.5D respectively. Over the follow-up period, the mean refractive change per months was -0.34D in the single IOL group and -0.45D in the piggyback IOL group. Postoperative complications were 12.5 % (1/8 eyes) in single IOL and 20.0% (1/5 eyes) in piggyback IOL. Reoperations were conducted for the complicated eyes in both groups. Conclusions: The rates of complications and reoperations were slightly higher in piggyback IOL than in single IOL. Nonetheless, additive correction for residual hyperopia was not needed in the piggyback IOL group. There was more deteriorative evidence of amblyopia in piggyback IOL than in single IOL.

초극소저출생체중아와 극소저출생체중아의 미숙아망막병증 발생 빈도와 위험 인자에 관한 연구

최성호,함돈일.Sung Ho Choi. M.D.. Don Il Ham. M.D. 대한안과학회 2006 대한안과학회지 Vol.47 No.6

Purpose: To evaluate the risk factors and prevalence of retinopathy of prematurity (ROP) in extremely low birth weight (ELBW) infants and very low birth weight (VLBW) infants. Methods: All babies were screened for ROP at a postconceptional age of 31 weeks or at 4 weeks of chronological age. We divided the infants into two groups according to birth weight < 1000 g (ELBW) and 1000~1500 g (VLBW), to compare the incidence of ROP and photocoagulation, and to retrospectively evaluate the risk factors. Results: Three hundred eight consecutive infants were included in the data analysis. The incidences of ROP were 70.5% (79/112) in ELBW infants and 36.7% (72/196) in VLBW infants (p<0.0001). 31 of 79 ELBW infants (39.2%) and 17 of 72 VLBW infants (23.6%) had undergone photocoagulation (p<0.0001). Among the various risk factors, mechanical ventilat6ion (p=0.039) and surfactant (p<0.000) were the independent risk factors associated with ROP in all infant groups by logistic regression analysis. In the ELBW group, however, surfactant injection was the only factor independently associated with ROP (p=0.008). The use of surfactant, the only risk factor in ELBW infants, was attributed with the initiation of ROP. However, it did not act as an aggravating factor. Conclusions: ELBW was associated with a higher incidence of ROP and laser photocoagulation. The results of this study emphasize that more special attention is needed for immature infants when ventilators and surfactants are used.