수열 합성 공정 조건이 티탄산 납의 상 형성에 미치는 영향

김경아,김정석,천채일,Kim, Kyoung-A,Kim, Jeong-Seog,Cheon, Chae-Il 한국세라믹학회 2011 한국세라믹학회지 Vol.48 No.1

Lead titanate ($PbTiO_3$) powder was prepared from lead nitrate ($Pb(NO_3)_2$) and titania ($TiO_2$) by hydrothermal route. Phase formation process was investigated by observing the phases formed in various experimental conditions like different KOH concentration, reaction temperature and time. $PbTiO_3$ powder was fabricated when the KOH concentration was 0.8M or higher. An intermediate compound, $PbTi_{0.8}O_{2.6}$, was formed at first by a reaction between PbO and $TiO_2$ and changed into $PbTiO_3$ powder with a perovskite crystal structure. A $PbTiO_3$ phase was formed in a shorter time when a KOH concentration was increased from 0.8M to 8M because a driving force for a $PbTiO_3$ formation was increased due to an increase in a degree of supersaturation. And $TiO_2$ (rutile) and $3PbO{\cdot}H_2O$ were observed at room temperature in a 0.8M KOH solution and $TiO_2$(rutile) and PbO (litharge) in a 8M KOH. A $PbTiO_3$phase was also formed in a shorter time at a higher reaction temperature as a reaction temperature influenced the rates for a dissolution and a precipitation.

Influence of nano-structured alumina coating treatment on shear bond strength between zirconia ceramic and resin cement

김동운,이정진,김경아,서재민,Kim, Dong-Woon,Lee, Jung-Jin,Kim, Kyoung-A,Seo, Jae-Min The Korean Academy of Prosthodonitics 2016 대한치과보철학회지 Vol.54 No.4

목적: 본 연구는 지르코니아 도재 표면의 나노구조 알루미나 코팅이 지르코니아와 레진 시멘트와의 전단결합강도에 미치는 영향을 알아보고자 하였다. 재료 및 방법: 지르코니아 원판 80개를 표면처리방법(산화알루미늄 분사처리(A), 산화알루미늄 분사 후 Rocatec 처리(R), 연마 후 나노구조 알루미나 코팅(PC), 산화알루미늄 분사 후 나노구조 알루미나 코팅(AC))에 따라 4개의 군으로 나누었다. 알루미나 코팅은 질산 알루미늄을 가수분해시킨 용액에 침적 후 $900^{\circ}C$에서 열처리 하여 시행하였다. 지르코니아 표면 코팅은 주사전자 현미경을 이용하여 관찰하였다. 레진 블럭을 레진 시멘트를 이용하여 각 실험군의 지르코니아 표면에 합착하고 열순환처리 전, 후의 전단결합강도를 측정하였다. 결과: 알루미나 코팅을 한 지르코니아 표면은 균일하고 치밀한 나노구조 알루미나가 관찰되었다. PC, AC 군은 열순환처리 전과 후 모두 A와 R 군에 비해 현저하게 높은 전단결합 강도를 보였다. A, R 군은 열순환처리 후에 급격한 결합강도의 감소를 보였으나, PC와 AC군은 열순환처리에 의해 유의할만한 결합강도의 감소를 보이지 않았다. 결론: 지르코니아 표면에 나노구조 알루미나 코팅처리하는 것은 레진시멘트와의 결합강도를 증가시키는 방법이다. Purpose: The aim of this study was to investigate whether the application of nano-structured alumina coating to the surface of Y-TZP could enhance the bond strength with resin cement. Materials and methods: A total of 80 zirconia plates were prepared and divided into four groups. : 1) airborne particle abrasion treatment (A) : 2) Rocatec treatment after airborne particle abrasion (R) : 3) nano-structured alumina coating treatment after polishing (PC) and 4) nano-structured alumina coating after airborne particle abrasion (AC). Alumina coating was formed by the hydrolysis of aluminium nitride (AlN) powder and heat treatment at $900^{\circ}C$. Coating patterns were observed with FE-SEM. Resin block was bonded to treated zirconia ceramics using resin cement. The shear bond strengths were measured before and after thermocycling. Results: The FE-SEM images show a dense and uniform nano-structured alumina coating structure, which enhances shear bond strength by increasing micro mechanical interlocking to resin cement. PC and AC groups showed higher shear bond strengths than A and R groups before and after thermocycling. A and R groups displayed significant drops in shear bond strength after thermocycling. However, PC and AC groups did not show any meaningful decreases in shear bond strength after thermocycling. Conclusion: Treatment of Y-TZP ceramics with nano-structured alumina coating could significantly increase their shear bond strength.

원발성 부갑상선항진증에 의한 악골의 다발성 갈색종양

김경아,고광준,Kim, Kyoung-A,Koh, Kwang-Joon 대한영상치의학회 2010 Imaging Science in Dentistry Vol.40 No.3

Brown tumor is usually diagnosed at the terminal stage of hyperparathyroidism. Diagnosis of this tumor is confirmed by endocrinologic investigations along with clinical and radiographic examination. Radiographical differential diagnosis of this tumor includes central giant cell granuloma, aneurysmal bone cyst, metastatic tumor, multiple myeloma, and Paget disease. This report presents a rare case of multiple brown tumors occurring at the maxilla and mandible, which was initially misdiagnosed as central giant cell granuloma. Plain radiographs demonstrated multiple well-defined multilocular radiolucency. CT images showed soft tissue mass with low attenuated lesions, perforation of the lingual cortical plate, and a heterogeneous mass at the right thyroid lobe. These findings were consistent with parathyroid adenoma. The patient had hypercalcemia, hypophosphatemia, and elevated alkaline phosphatase level. Surgical excision of the tumor was performed. No recurrence was observed during a 28-month follow-up.

소아물리치료사와 소아작업치료사의 보조공학 활용 수준 및 자신감

김경아,정동훈,Kim, Kyoung-A,Jeong, Dong-Hoon 대한물리치료학회 2013 대한물리치료학회지 Vol.25 No.1

Purpose: This study sought to identify the utilization and confidence in assistive technology (AT) for pediatric physical therapists (PPTs) and pediatric occupational therapists (POTs) for the purpose of improving the utilization of AT in clinics. Methods: The subjects of this study were 167 therapists (98 PPTs and 69 POTs) who work at general hospitals, welfare centers, facilities for the disabled, and special education schools in Seoul and Gyeonggi province. The frequency analysis and chi-squared test were used. Results: This study found that both PPTs and POTs recognize that AT benefits infants with disabilities; however, they show low confidence in using AT. Applications of AT are concentrated on wheelchairs for mobility and assistance with seating position, with orthotics/prosthetics for both purposes. POTs were found to use a wider variety of AT devices. While both PPTs and POTs frequently select/recommend devices, both groups are less involved with delivery methods, manufacture of devices, and education on AT use. Conclusion: These findings show the actual conditions of utilization and confidence in AT of PPTs and POTs deeply involved with AT, and emphasize that AT training is essential for pediatric treatment by comparing domestic and foreign studies.

경기 지역 대기 오염 농도의 시간 변동성과 관련된 종관 기상 상태의 전개

임규호(Gyu-Ho Lim),김경아(Kyoung-A Kim) 한국기상학회 1996 Asia-Pacific Journal of Atmospheric Sciences Vol.32 No.1

대학의 인성기반 교양교육 현황 및 방향모색 : ‘세계시민교육과 리더십’을 중심으로

김경아(Kim, Kyoung A),김수진(Kim, Soo Jin),윤희정(Yun, Hui-Jeong) 다빈치미래교양연구소 2020 교양학연구 Vol.0 No.12

The purpose of this study is to investigate the direction of a general education model based on ‘Global citizenship education and leadership’. For the purpose of collecting information, we organized FGIs in 2020. The FGI was conducted with the expert group of 6 participants from January 20th to May 6th. To extract data of detail and depth, the study implemented three series of focus group interview. The semi-structured interview items were passed through a formal review process of the institutional Ethics Committee(IRB). Furthermore, under the participants’ pre-consents of recording, all recorded data were categorized through transcripts process. The results of the study are as follows. As a result of the study, a total of 9 subcategories were derived from 3 areas of categories, including developing a Character competency based on ‘Global Citizenship Education and Leadership’, ‘construction an education system’, ‘Reinforcing an effective education’. In sum, this research provided that Global Citizenship Education and Leadership is very meaningful education model, which can contribute on reinforcing university student’s positive self-image and capability and mission as a global citizen. In turn, this investigation would lead to a discussion on the implications and possibilities of cultivating future global leaders.

갑상선 선종 환자에서 발견된 알파 태아단백 상승을 동반한 Sertoli-Leydig Cell Tumor

오종은 ( Jong Yn Oh ),강광석 ( Kwang Sok Kang ),박선영 ( Seon Young Park ),문정범 ( Jeong Beom Moon ),김경아 ( Kyoung A Kim ),이영호 ( Young Ho Lee ),이금노 ( Keum Nho Lee ) 대한산부인과학회 2004 Obstetrics & Gynecology Science Vol.47 No.6

Sertoli-Leydig cell tumor (SLCT) which belong to the group of sex-cord stromal tumors is a rare ovarian tumor. It usually develops the symptom of masculinization by excessive testosterone from the Leydig cell. In most cases, SLCTs are unilaterally localized (97-98%) and prognosis prove generally favorable with 5-year survival rate (79-90%). Recurrence is rare after a complete resection as well. Rare SLCTs secrete the alpha-fetoprotein (AFP). There is a increasing tendency for the SLCTs that have heterologous elements and low differentiation to secrete the AFP, which is useful in diagnosis of recurrence. The association of a thyroid adenoma and a SLCT has been described rarely. The relation between these two tumors has been suggested neoplasm. It seems likely that this tumor complex is genetically determined by the aspect of familial neoplastic syndromes. We experienced a case of Sertoli-Leydig cell tumor with AFP-producing cells in a 33-years old woman who has past history of thyroid adenoma, amenorrhea and a huge abdominal mass. Therefore, we present it with a brief review of literature.

비대면 코칭 기반 대학 비교과 프로그램 개발 및 효과성 : S여자대학교를 중심으로

김경아(Kim, Kyoung A) 한국교양교육학회 2022 교양교육연구 Vol.16 No.2

코로나 바이러스 감영증-19 이후 급변하는 사회 환경에 대처할 수 있는 다양한 비대면 비교과 프로그 램에 대한 요구가 이어지고 있다. 이에 본 연구는 S여자대학교 학생들을 대상으로 ‘미래를 여는 푸른힘’ 프로그램을 개발, 실시한 후 그 효과성을 탐색하고자 한다. 이를 위해 비교과 시스템을 통하여 실험집단과 통제집단 각 20명씩을 선정하였다. 또한 프로그램의 효과성을 파악하기 위하여 양적⋅질적 접근을 실시하였다. 프로그램은 리더십 워크숍, 리더십 진단, 그룹 코칭, 일대일 코칭 등으로 구성되었으며, 모두 온라인 플랫폼 줌(zoom)으로 2022년 1월 17일 ~ 2월 24일까지 총 7회차 진행되었다. 프로그램 실시 결과, 실험집단은 진로결정자기효능감과 회복탄력성에서 사전-사후검사 간에 유의한 차이를 나타냈다. 또한, FGI 분석 결과 프로그램 모델, 자기이해의 확장, 미래 비전의 고도화 등의 총 3개 범주가 도출되었다. 이상과 같이 본 프로그램은 진로결정에 대한 확신과 긍정 에너지를 함양시킬 뿐 아니라 나아가 글로벌 리더로서의 미래 설계를 고취시키는데 기여했음을 알 수 있다. Demand for various non-face-to-face, non-curricular programs that can cope with the rapidly changing social environment after Corona-19 continues. Therefore, this study aims to explore the effectiveness of S Women s University students after developing and implementing the ‘Blue Power to Open Tomorrow’ program. For this purpose, 20 university students each were selected from the experimental group and the control group through the non-examination system. In addition, quantitative and qualitative approaches were implemented to understand the effectiveness of the program. The program consisted of a leadership workshop, a leadership diagnosis group-coaching section, and one-on-one coaching activities, all of which were conducted through online platform Zoom from January 17th to February 24th, 2022. As a result of the program’s implementation, the experimental group showed a significant difference regarding their pre-test and post-test scores in the areas of career decision self-efficacy and resilience. In addition, as a result of FGI analysis, a total of three categories were derived: the program model, the expansion of self-understanding, and the advancement of future vision. As mentioned above, we can see that this program not only fostered confidence in students when it came to their ability to make career decisions, but that it also inspired them in their future designs as global leaders and instilled in them a marked level of positive energy.

Problem-Based Learning을 활용한 가족자원경영학 수업모형개발 및 실시: “여가문화와 생활관리” 수업사례를 중심으로

김경아 ( Kyoung A Kim ),박미석 ( Mee Sok Park ) 대한가정학회 2014 Family and Environment Research Vol.52 No.6

The purpose of this study is to present a practical class design model that applies the problem-based learning (PBL) method to the subject of home economics. To begin with, a specific class model example was developed by conducting thorough document research and expert consulting. Two modules, named “Click! Global Leisure Environment” and “Happy Leisure Product Launching” were presented as the PBL questions. The case study focused upon in this research is an elective course called “Leisure Culture and Life Management.” The 21 students enrolled in this course were considered in this study. Two teaching methods, namely a face-to-face teaching method and a web-based system “Snowboard” teaching method, were used to run the class. The research results are as follows: first, theoretical research and program development and demonstration were practiced with five different age groups: childhood, adolescence, university student, middle age, and senescence. Then, self-evaluation, peer evaluation, and group evaluation were conducted to motivate the students. Finally, a class evaluation was conducted by questioning the lecturer, who ranked well, scoring higher than or equal to 4.0 points out of 5.0 on all the questions. Through the PBL method, students showed an improved study attitude with more proactive participation in the class, they strengthened their communication skills and created a synergy with their team members. This study has significant meaning because it is the first research to apply the PBL method to home economics. Therefore, we expect other curricula to apply PBL and fully utilize this teaching method as well in the future.

청소년의 셀프리더십이 예절수행 및 학교생활적응력에 미치는 영향

김경아(Kim Kyoung-A),장효주(Jang Hyo-Ju) 가정과삶의질학회 2010 가정과삶의질연구 Vol.28 No.6