Investigation of Impact of Vapor Pressure on Hybrid Streamflow Prediction Modeling

Hasan Törehan Babacan,Ömer Yüksek,Fatih Saka 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.2

In this study, daily streamflow prediction models have been developed for Aksu Stream, in the Eastern Black Sea Basin of Turkey. To reach at this aim, hybrid artificial intelligence models have been developed, by using a new parameter, vapor pressure. Vapor pressure efficiency has been investigated for hybrid streamflow prediction models. Streamflow prediction models have been developed by using Artificial Neural Network (ANN), Multivariate Adaptive Regression Splines (MARS), and their hybrid models. Hybridization of streamflow prediction models has been made with Wavelet Transform (WT). 10 yearly daily hydrological (discharge (m³/s)), meteorological (precipitation (mm), vapor pressure (hPA)) data, and seasonality coefficient have been used as input data of streamflow prediction models. In the selection of the best streamflow prediction model, 14 different day-delayed input combinations have been established by using 10 yearly data. As a result of the study, the highest flow forecast performance model has been determined as Wavelet Artificial Neural Network (WANN) in the study area. In the WANN model, the vapor pressure parameter was found to reduce the error by about 18.5% and improve the forecast performance. This study has concluded that, vapor pressure may be used in the future studies as a new parameter for streamflow prediction models.

Comparison of retention characteristics of Essix and Hawley retainers

Demir, Abdullah,Babacan, Hasan,Nalcaci, Ruhi,Topcuoglu, Tolga The Korean Association Of Orthodontists 2012 대한치과교정학회지 Vol.42 No.5

Objective: We aimed to compare the retention characteristics of Essix and Hawley retainers. Methods: Adolescents undergoing fixed appliance treatment at 2 centers were recruited for this study. Twenty-two patients (16 women and 6 men) wore Essix retainers (Essix group) while 20 (14 women and 6 men) wore Hawley retainers (Hawley group). The mean retention time was 1 year, and the mean follow-up recall time for both groups was 2 years. Two qualified dental examiners evaluated the blind patient data. Maxillary and mandibular dental casts and lateral cephalograms were analyzed at 4 stages: pretreatment (T1), post-treatment (T2), post-retention (T3), and follow-up (T4). Results: The results revealed that Essix appliances were more efficient in retaining the anterior teeth in the mandible during a 1-year retention period. The irregularity index increased in both arches in both groups after a 2-year post-retention period. The mandibular arch lengths increased during treatment and tended to return to their original value after retention in both groups; however, these changes were statistically significant only in the Hawley group. Cephalometric variables did not show any significant differences. Conclusions: The retention characteristics of both Essix and Hawley retainers are similar.

Comparison of retention characteristics of Essix and Hawley retainers

Abdullah Demir,Hasan Babacan,Ruhi Nalcacı,Tolga Topcuoglu 대한치과교정학회 2012 대한치과교정학회지 Vol.42 No.5

Objective: We aimed to compare the retention characteristics of Essix and Hawley retainers. Methods: Adolescents undergoing fixed appliance treatment at 2 centers were recruited for this study. Twenty-two patients (16 women and 6 men) wore Essix retainers (Essix group) while 20 (14 women and 6 men) wore Hawley retainers (Hawley group). The mean retention time was 1 year, and the mean follow-up recall time for both groups was 2 years. Two qualified dental examiners evaluated the blind patient data. Maxillary and mandibular dental casts and lateral cephalograms were analyzed at 4 stages: pretreatment (T1), post-treatment (T2), post-retention (T3), and follow-up (T4). Results: The results revealed that Essix appliances were more efficient in retaining the anterior teeth in the mandible during a 1-year retention period. The irregularity index increased in both arches in both groups after a 2-year post-retention period. The mandibular arch lengths increased during treatment and tended to return to their original value after retention in both groups; however, these changes were statistically significant only in the Hawley group. Cephalometric variables did not show any significant differences. Conclusions: The retention characteristics of both Essix and Hawley retainers are similar.

Late development of a mandibular second premolar

Ali Altug Bicakci,Cenk Doruk,Hasan Babacan 대한치과교정학회 2012 대한치과교정학회지 Vol.42 No.2

In this report, we present the case of a girl with delayed odontogenesis of a lower second premolar for which she was followed up for 8.5 years. Congenital absence of permanent mandibular second premolars was observed at the initial radiographic examination at 8 years and 1 month. One year later, during the treatment period, an unexpected odontogenesis of a right second premolar was diagnosed on follow-up radiography. The original treatment plan was revised and a new plan was successfully implemented. This unusual case showed that the orthodontist’s clinical philosophy must be flexible because unexpected situations can arise, especially when treating growing patients.

Effects of direct and indirect bonding techniques on bond strength and microleakage after thermocycling

F₁rat o''ztu''rk,Hasan Babacan,Ruhi Nalc.ac₁,Alper Kus.tarc₁ 대한치과교정학회 2009 대한치과교정학회지 Vol.39 No.6

Objective: The purpose of this study was to compare the shear bond strength (SBS) of brackets and microleakage of a tooth-adhesive-bracket complex bonded with a direct and an indirect bonding technique after thermocycling. Methods: Fifty non-carious human premolars were divided into two equal groups. In the direct bonding group a light-cured adhesive and a primer (Transbond XT) was used. In the indirect-bonding group, a light-cured adhesive (Transbond XT) and chemical-cured primer (Sondhi Rapid Set) were used. After polymerization, the teeth were kept in distilled water for 24 hours and thereafter subjected to thermal cycling (500 cycles). For the microleakage evaluation, 10 teeth from each group were further sealed with nail varnish, stained with 0.5% basic fuchsin for 24 hours, and examined under a stereomicroscope. Fifteen teeth from each group were used for SBS testing with the universal testing machine and adhesive remnant index (ARI) evaluation. Data were analyzed using the Mann-Whitney U test, Chi-square test, and Fisher's exact test. Results: There were no statistical differences on SBS and microleakage between the two bonding techniques. The indirect bonding group had a significantly lower ARI score. Bracket failures were obtained between enamel-resin interfaces. Conclusions: The type of bonding technique did not significantly affect the amount of microleakage and SBS. 본 연구는 직접 또는 간접 부착법으로 부착한 교정용 브라켓을 열순환 처리 후에 전단 결합 강도(shear bond strength, SBS)와 치아-접착제-브라켓 복합체의 미세 누출을 비교하기 위하여 시행하였다. 50개의 치아우식증이 없는 사람 소구치를 구하여 동등한 2개의 군으로 나누었다. 직접 부착군에서는 광중합 접착제 및 primer (Transbond XT)를 사용하였고 간접 부착군에서는 광중합 접착제와(Transbond XT) 화학중합 primer (Sondhi Rapid Set)를 사용하였다. 중합 후에 치아는 24시간 동안 증류수에 보관하였고 이후 500회 열순환 처리를 하였다. 미세누출의 평가를 위해 각 군에서 10개의 치아에 nail varnish로 추가 봉연을 실시하고 0.5% basic fuchsin에 24시간 동안 염색한 후 입체현미경으로 검경하였다. 만능시험기를 이용하여 각 군의 치아 15개로 SBS를 계측하였고 adhesive remnant index (ARI)를 평가하였다. 결과 자료는 Mann-Whitney U test, Chi-square test, Fisher's exact test로 통계 분석하였다. 직접 부착군과 간접 부착군 사이에 SBS 및 미세누출의 통계적으로 유의한 차이는 보이지 않았으며 간접 부착군에서 통계적으로 유의하게 ARI 점수가 낮았다. 브라켓의 탈락은 법랑질-레진 계면에서 발생하였다. 이상의 결과로 보아 부착법의 차이는 미세누출의 양과 SBS에 유의한 영향을 미치지 않는다.

Late development of a mandibular second premolar

Bicakci, Ali Altug,Doruk, Cenk,Babacan, Hasan The Korean Association Of Orthodontists 2012 대한치과교정학회지 Vol.42 No.2

In this report, we present the case of a girl with delayed odontogenesis of a lower second premolar for which she was followed up for 8.5 years. Congenital absence of permanent mandibular second premolars was observed at the initial radiographic examination at 8 years and 1 month. One year later, during the treatment period, an unexpected odontogenesis of a right second premolar was diagnosed on follow-up radiography. The original treatment plan was revised and a new plan was successfully implemented. This unusual case showed that the orthodontist's clinical philosophy must be flexible because unexpected situations can arise, especially when treating growing patients.

A reliable method for evaluating upper molar distalization

Ruhi Nalcaci,Ayse Burcu Kocoglu-Altan,Ali Altug Bicakci,Firat Ozturk,Hasan Babacan 대한치과교정학회 2015 대한치과교정학회지 Vol.45 No.2

Objective: The aim of this study was to evaluate the reliability of measurements obtained after the superimposition of three-dimensional (3D) digital models by comparing them with those obtained from lateral cephalometric radiographs and photocopies of plaster models for the evaluation of upper molar distalization. Methods: Data were collected from plaster models and lateral cephalometric radiographs of 20 Class II patients whose maxillary first molars were distalized with an intraoral distalizer. The posterior movements of the maxillary first molars were evaluated using lateral cephalometric radiographs (group CP), photocopies of plaster models (group PH), and digitized 3D models (group TD). Additionally, distalization and expansion of the other teeth and the degrees of molar rotation were measured in group PH and group TD and compared between the two groups. Results: No significant difference was observed regarding the amount of molar distalization among the three groups. A comparison of the aforementioned parameters between group PH and group TD did not reveal any significant difference. Conclusions: 3D digital models are reliable to assess the results of upper molar distalization and can be considered a valid alternative to conventional measurement methods.