New Approaches to Xerostomia with Salivary Flow Rate Based on Machine Learning Algorithm

이연희,이연희,어규식,박희경 대한치의학회 2023 Journal of korean dental science Vol.16 No.1

Purpose: We aimed to investigate the objective cutoff values of unstimulated flow rates (UFR) and stimulated salivary flow rates (SFR) in patients with xerostomia and to present an optimal machine learning model with a classification and regression tree (CART) for all ages. Materials and Methods: A total of 829 patients with oral diseases were enrolled (591 females; mean age, 59.29±16.40 years; 8~95 years old), 199 patients with xerostomia and 630 patients without xerostomia. Salivary and clinical characteristics were collected and analyzed. Result: Patients with xerostomia had significantly lower levels of UFR (0.29±0.22 vs. 0.41±0.24 ml/min) and SFR (1.12±0.55 vs. 1.39±0.94 ml/min) (P<0.001), respectively, compared to those with non-xerostomia. The presence of xerostomia had a significantly negative correlation with UFR (r=–0.603, P=0.002) and SFR (r=–0.301, P=0.017). In the diagnosis of xerostomia based on the CART algorithm, the presence of stomatitis, candidiasis, halitosis, psychiatric disorder, and hyperlipidemia were significant predictors for xerostomia, and the cutoff ranges for xerostomia for UFR and SFR were 0.03~0.18 ml/min and 0.85~1.6 ml/min, respectively. Conclusion: Xerostomia was correlated with decreases in UFR and SFR, and their cutoff values varied depending on the patient’s underlying oral and systemic conditions.

스트리밍 데이터 환경에서 차분 프라이버시를 적용한 빈발 항목 집합의 갱신 지연 기법

이연희,박석 한국정보과학회 2019 정보과학회 컴퓨팅의 실제 논문지 Vol.25 No.2

실시간으로 사용자의 정보를 수집하여 분석하는 데이터 마이닝은 여러 분야에서 사용되고 있다. 또한 사용자의 민감한 정보를 실시간으로 수집하여 빈발 항목 집합을 구하는 연구가 많이 되고 있다. 빈발 항목 집합들은 여러 사용자들로부터 얻어진 데이터이기 때문에 프라이버시 문제가 없어 보이지만 강력한 사전지식을 가진 공격자는 빈발 항목 집합으로부터 사용자의 정보를 추론할 수 있다. 이러한 공격자로부터 개인의 프라이버시를 지키기 위해 차분 프라이버시 기법을 적용하고자 한다. 따라서 본 논문에서는 차분 프라이버시 기법을 적용하여 사용자 개인의 프라이버시를 보호할 수 있는 스트리밍 환경에서의 빈발 항목 집합 마이닝 기법을 제안하고자 한다. Data mining which collects and analyzes user information is used in many fields. There are many studies on how to collect frequent item sets by collecting user's sensitive information in this generation. Because most of the item sets are data obtained from several users, there seems to be no privacy problem. However, the attacker with strong prior knowledge can infer user information from frequent item set and supports. In order to protect personal privacy from the attacker, this study proposed a frequent item set mining technique in streaming environment that can protect privacy of users by applying differential privacy technique.

한 심미주의자의 반심미주의적 담론

이연희 한독문학번역연구소 1999 번역연구 Vol.7 No.-

피부미용사의 위생관리실천에 관한 조사연구

이연희,김현화,홍승정 한국피부미용향장학회 2014 한국피부미용향장학회지 Vol.9 No.3

In order to investigate hygienic practice rates among skin care specialist beauticians participating in the skin care service industry, we carried out a total of 231 surveys consisting of 15 questions which investigated personal hygiene, instrument sterilization, and environmental hygiene. These surveys were conducted between January 31 and February 15, 2013. They were based on age, educational background, financial circumstances and job position. The results did not show any significant differences regarding hygienic practices between age groups or education levels, but there were differences between financial circumstances and job position (F=2.219, p 0.05, F= 1.932, p 0.05). There were also significant differences between personal hygiene within the same age groups (F=2.722, p -.05). The total difference in personal hygiene as an influence of age was shown to be 2.2%. There were significant differences regarding personal hygiene and environmental hygiene according to financial circumstances (F=2.946, p 0.05, F=3.506, p 0.01). The total difference in personal hygiene as an influence of financial circumstances was 3.3%, while the total difference in environmental hygiene as an influence of financial circumstances was 4.2%. Therefore, personal hygiene was shown to be influenced by age and financial circumstances, while environmental hygiene was shown to be influenced by financial circumstances, and especially by job position. Education levels had no influence on hygiene. We believe this shows that hygiene is being applied in the skin care industry as training in hygiene is provided in the early stages of training.; however, it would seem that additional training is lacking. There is a need for improved professional responsibility among skin care specialist beauticians via more thorough training in hygienic practices.

스티렌-아크릴산 공중합체의 들뜬이합체 연구

이연희,강성철,김강진,Lee, Yeon Hui,Gang, Seong Cheol,Kim, Gang Jin 대한화학회 1990 대한화학회지 Vol.34 No.1

스티렌과 아크릴산을 azobisisobutyronitrile 개시제로 사용하여 free radical 반응으로 스티렌-아크릴산이 공중합체(PSAA)를 합성하고, PSAA에 $Eu^{3+}$를 치환시킨 PSAA-Eu착물을 합성하였다.PSAA와 PSAA-Eu 착물을 최대흡수 파장인 260nm에서 들뜨게하여 형광방출 스펙트럼을 조사해 본 결과, 스티렌의 몰비가 증가함에 따라 294nm에서 나타나는 단위체 띠는 감소하고, 330nm에서 보이는 들뜬이합체 띠는 증가하였다. PSAA-EU, PSAA-Tb 그리고 PSAA-Eu-Tb의 들뜬이합체 형광세기가 비슷하므로, 금속이온의 종류는 PASS의 들뜬이합체에 크게 영향을 미치지 않는 것을 알 수 있었다. 들뜬이합체 형성에 대한 세 가지 다른 이론적 모델들을 사용하여 실험결과들에 적용함으로써 격리된 스티렌에서 격리되지 않은 스티렌으로 에너지 이동이 일어날 수 있다는 것을 알 수 있었다. Copolymers (PSAA) of styrene-acrylic acid were prepared through a free radical mechanism using azobisisobutyronitrile as an initiator. The fluorescence emission spectra of PSAA and the styrene-acrylic acid copolymers complexed with $Eu^{3+}$ (PSAA-Eu) were studied. The excimer fluorescence, centered at 330 nm, increases when the styrene mole fraction increases. Since the excimer fluorescence intensities of PSAA-EU, PSAA-Tb and PSAA-Eu-Tb were almost same, it appears that the kind of metal ion does not affect the excimer fluorescence. An interpretation of the results which takes into account the statistical composition of the copolymers, indicates that energy migration can occur from isolated to non-isolated styrene units.

한일 디지털 음악 시장 비교

이연희,권혁기 한일경상학회 2012 한일경상논집 Vol.57 No.-

There are four major differences between Korean and Japanese digital music market. First, despite the same technological changes made in both Korea and Japan, the two countries show distinctive changes in the size and structure of the digital music market. Second, the structure of the supply chain is different. Third, revenue sharing structures of copyright holders and distributors are different. Lastly, the presence of free music files and sanctions on the illegal music market were different. Further analysis reveals the following. First and foremost, it was found that mobile Internet has been used widely to download music contents in Japan. In terms of the supply chain, copyright holders were stronger than distributors. In addition, Japan applied strict copyright laws and regulations against illegal files with the advent of Internet. In contrast, music was mainly downloaded through wired Internet(PC Internet) in Korea. Music download has grown up side by side with wired Internet which showed faster speed rate in Internet technology and distribution than the wireless did. Furthermore, since mobile web was not open, it was difficult for CP to participate in the mobile contents market. This enabled carriers to set advantageous strategies in terms of supply chain. These days, copyright laws are much more stricter than ever, but yet they are not good enough to restrict all the illegal market formed earlier, and there are still much room for the sanctions and restrictions.

좋은 수업에 대한 보육교사의 인식 분석

이연희,이춘자 한국육아지원학회 2019 한국육아지원학회 학술대회지 Vol.2019 No.11

2000학년도 신입생의 정신건강 분석

이연희 청주대학교 학생생활연구소 2000 學生生活硏究 Vol.22 No.-

독자가 편집실에

이연희,황석연 하이미디어피앤아이 2025 여행스케치 : 행복을 담은 여행잡지 Vol.23 No.6

서원대생의 취업 의식에 관한 실태조사

이연희 서원대학교 학생생활연구소 1998 학생생활연구 Vol.16 No.-

The purpose of this survey is to know about job consciousness of seowon university students. There took park in 584 students with survey participant. A survey content largely contains four parts - career decision making, job choice, university life satisfaction, job center and student guidance center. The results were as follows : 1. 80.5% of students think about career, 67.1% desire job after graduation, 34.9% has cognizance of arranging term for a course in junior. 2. The majority of student hopes teacher, bureaucracy as job. They consider firstly both language and major. They meditate peaceful and harmonious relations among persons. 3. Comparatively they put life into their school but their satisfaction rate is average. 4. Positively job center and student guidance center must know their role to student because of their low acknowledge. In conclusion the results show that student guidance center emphasizes as necessary for students to enforce psychological test, counseling, survey with job, etc.