센서 위치 보정을 통한 원추형 자기베어링 로터의 위치 제어

양승준,곽병철,김주영,이재응 중앙대학교 기술과학연구소 2001 기술과학연구소 논문집 Vol.31 No.-

이 논문에서는 원추형 자기베어링으로 지지된 고속 연삭기 로터의 정밀진동제어에 관한 연구를 수행하였다. 이러한 연구 목적으로 달성하기 위하여 전력증폭기와 원추형 자기베어링을 포함한 각 축에 대하여 이산시간 모델을 규명하였으며, 그 결과를 모의 제어기의 설계시 활용하였다. 또한 제어기의 입력값을 조절하여 자기베어링 공간내에 로터가 최적의 위치에 놓일 수 있도록 조정하였으며, 위치를 검출하는 센서와 전자기적 흡인력을 발생하는 액츄에이터 사이의 위치 불일치를 보정하는 방법을 개발하고 실험 대상에 적용하였다. 그 결과 front 방향과 rear 방향 사이의 연성 효과가 확연히 감소되었고, 로터 회전시의 진폭이 50,000 rpm에서 ±7㎛ 이내의 성능을 보이는 정밀 진동 제어를 수행하였다. In this paper, the precise vibration control problems of high speed grinding rotor supported by cone-shaped active magnetic bearings are investigated. Toward this end, each part of the system including power amplifiers and magnetic bearing systems are identified s discrete time models, and the results are used for controller design. In addition, the correction method of the position error between sensor and actuator are developed and implemented for the experiments. As a result, the coupling effect between front and rear axis are decreased and the amplitudes of rotor vibration are controlled within ±7㎛ at 50,000 rpm.

Physical Properties of Indium Reduced Materials for Transparent Conductive Electrodes

Seung-Hoon Kwak,Min-Gi Kwak,Sung-Jei Hong,Byeong-Kwon Ju,Jeong In Han 한국태양광발전학회 2014 Current Photovoltaic Research Vol.2 No.1

In this paper, indium reduced materials for transparent conductive electrodes (TCE) were fabricated and their physical properties were evaluated. Two of materials, indium-zinc-tin oxide (IZTO) and aluminum (Al) were selected as TCE materials. In case of IZTO nanoparticles, composition ratios of In, Zn and Sn is 8:1:1 were synthesized. Size of the synthesized IZTO nanoparticles were less than 10 nm, and specific surface areas were about 90 ㎡ /g indicating particle sizes are very fine. Also, the IZTO nanoparticles were well crystallized with (222) preferred orientation despite it was synthesized at the lowered temperature of 300°C. Composition ratios of In, Zn and Sn were very uniform in accordance with those as designed. Meanwhile, Al was deposited onto glass by sputtering in a vacuum chamber for mesh architecture. The Al was well deposited onto the glass, and no pore was observed from the Al surface. The sheet resistance of Al on glass was about 0.3 Ω/□ with small deviation of 0.025 Ω/□, and adhesion was good on the glass substrate since no pelt-off part of Al was observed by tape test. If the Al mesh is combined with ink coated layer which is consistent of IZTO nanoparticles, it is expected that the good and reliable metal mesh architecture for TCE will be formed.

Enhancement of Characteristics of a Touch Sensor by Controlling the Multi-Layer Architecture of a Low-Cost Metal Mesh Pattern

Kwak, Seung-Hoon,Kwak, Min-Gi,Ju, Byeong-Kwon,Hong, Sung-Jei American Scientific Publishers 2015 Journal of Nanoscience and Nanotechnology Vol.15 No.10

Physical Properties of Indium Reduced Materials for Transparent Conductive Electrodes

Kwak, Seung-Hoon,Kwak, Min-Gi,Hong, Sung-Jei,Ju, Byeong-Kwon,Han, Jeong In Korea Photovoltaic Society 2014 Current Photovoltaic Research Vol.2 No.1

In this paper, indium reduced materials for transparent conductive electrodes (TCE) were fabricated and their physical properties were evaluated. Two of materials, indium-zinc-tin oxide (IZTO) and aluminum (Al) were selected as TCE materials. In case of IZTO nanoparticles, composition ratios of In, Zn and Sn is 8:1:1 were synthesized. Size of the synthesized IZTO nanoparticles were less than 10 nm, and specific surface areas were about $90m^2/g$ indicating particle sizes are very fine. Also, the IZTO nanoparticles were well crystallized with (222) preferred orientation despite it was synthesized at the lowered temperature of $300^{\circ}C$. Composition ratios of In, Zn and Sn were very uniform in accordance with those as designed. Meanwhile, Al was deposited onto glass by sputtering in a vacuum chamber for mesh architecture. The Al was well deposited onto the glass, and no pore was observed from the Al surface. The sheet resistance of Al on glass was about $0.3{\Omega}/{\square}$ with small deviation of $0.025{\Omega}/{\square}$, and adhesion was good on the glass substrate since no pelt-off part of Al was observed by tape test. If the Al mesh is combined with ink coated layer which is consistent of IZTO nanoparticles, it is expected that the good and reliable metal mesh architecture for TCE will be formed.

The role of postoperative neutrophil-to-lymphocyte ratio as a predictor of postoperative major complications following total gastrectomy for gastric cancer

Jae Seung Kwak,Sung Gon Kim,Sang Eok Lee,Won Jun Choi,Dae Sung Yoon,In Seok Choi,Ju Ik Moon,Nak Song Sung,Seong Uk Kwon,In Eui Bae,Seung Jae Lee,Seung Jae Roh 대한외과학회 2022 Annals of Surgical Treatment and Research(ASRT) Vol.103 No.3

Purpose: This study was performed to investigate the role of the perioperative neutrophil-to-lymphocyte ratio (NLR) as an early predictor of major postoperative complications after total gastrectomy for gastric cancer. Methods: This single-center, retrospective study reviewed consecutive patients with gastric cancer who underwent total gastrectomy at a single institution from March 2009 to March 2021. The postoperative complications were graded according to the Clavien-Dindo classification. We analyzed the patient demographics and surgical outcomes according to the grade of postoperative complications in the major complications group (≥grade III) and the no major complications group (<grade III and no complication). Laboratory tests were performed preoperatively and on postoperative days (POD) 2 and 5 to determine the NLR. Results: Out of 212 patients (mean age, 64.1 years; 152 male [71.7%]), 63 (29.7%) underwent minimally invasive surgery. Twenty-five (11.8%) were in the major complications group and 187 (88.2%) were in the no major complications group. There was a significant difference in the NLR on POD 2 (16.54 . 8.83, P = 0.033) between the 2 groups. According to the receiver operating characteristic curve for the NLR on POD 2, the cutoff was calculated to be 9.6. In multivariate analysis, an NLR on POD 2 of ≥9.6 and an American Society of Anesthesiologists physical status classification of ≥III were statistically significant predictors of major postoperative complications. Conclusion: Determination of the NLR on POD 2 is a simple and useful method for the early prediction of major complications after total gastrectomy for gastric cancer.

사랑반 다문화가정 영아의 언어 및 정서적 지원을 위한 전래동요놀이의 협력적 실행

곽승주 ( Kwak Seung-ju ) 한국유아교육학회 2020 유아교육연구 Vol.40 No.2

본 연구는 전래동요놀이를 통해 다문화가정 영아의 언어 및 정서적 지원을 도모하는데 목적이 있다. 이를 위해 참여관찰 및 면담을 중심으로 하는 질적 방법으로써, 연구자가 교육현장에서 다문화가정 영아들에게 전래동요놀이 활동을 전개하는 실행연구방법이 적용되었다. 그 결과 첫째, 전래동요놀이의 실행과정은 단동십훈을 통해 우리 가락, 운율과 마주하기, 주고받는 노래로 전래동요놀이와 친숙해지기, 노래와 움직임이 어우러진 동작놀이로 경험하기, 또래와 함께 하는 집단 놀이로 확장하기, 전래동요놀이 속에서 정서적 위안 및 안정감 찾기로 전개되었다. 둘째, 다문화가정 영아들이 전래동요놀이에 참여함으로써 공감각적 반복을 통한 언어표현의 기회가 증대되었고, 어린이집과 가정에서의 놀이공유를 통해 언어경험이 확장되었으며, 영아와 교사, 어머니의 정서공유 및 정서적 유대감이 강화되는 교육적 의의를 발견할 수 있었다. The objective of this study is to promote the linguistic and emotional support of toddler from multi-cultural families through play using traditional children’s song. For this, qualitative method was utilized focusing on the participation observation and in-depth interview. Action research was applied in which the researcher would perform the play using traditional songs for multi-cultural toddler in the site of education. The results are as following. First, the action process of play using traditional song included acclimatization to Korean melody and rhythm through Dandongsiphoon, familiarization with traditional plays by exchanging songs, experiencing the movement plays mixed with songs and movements, and feeling psychological stability through play using traditional song. Second, the use of traditional children’s song provided the participating multi-cultural toddler with educational significances such as an increased opportunity of linguistic expression through the synesthetic repetition, an expanded linguistic experience in daycare center and home through the sharing of play, and strengthened emotional sharing and bond between toddler and teacher/mother.

2세 영아의 정서표현에 관한 문화기술저 탐구

곽승주(Kwak Seung Ju) 한국육아지원학회 2006 육아지원연구 Vol.1 No.2

본 연구는 일상에서 빈번하게 표출되는 영아의 부정적 정서에 대한 심층적이고 맥락적인 이해를 통해 효율적인 영아보육을 도모하는데 그 목적이 있다. 이를 위해 가정과 보육시설에서 참여관찰과 심층면담을 중심으로 영아의 부정적 정서표현을 탐색하였다. 보육시설에서 영아의 부정적 정서는 놀이감이나 놀이영역, 교사의 관심과 애정을 확보하기 위한 수단으로 사용되었으며 교사는 이때 보여지는 부정적 정서표현들을 영아의 언어적․사회적 능력과 기술의 부족으로 인식하였다. 따라서 교사는 영아의 부정적 정서를 교육과 통제의 대상으로 여기고 이를 지속적으로 언어화 시키면서 조절 및 통제에 중점을 두고 상호작용하는 경향을 나타냈다. 반면 가정에서의 부정적 정서는 매우 다양하고 자연스럽게 나타났으며 영아는 부정적 정서를 적극적인 자기표현의 수단으로 사용하였다. 또한 어머니는 영아의 부정적 정서표현을 의사소통의 한 방식으로 이해하였으며 언어적․신체적 상호작용을 통해 부정적 정서표현을 놀이의 단서로 활용하며 긍정적인 정서로 전환시키기도 하였다. The purpose of this study was to observe and understand expression of toddler's negative emotions with teachers, peers and mother in context. This study also examined how teachers, peers and mother understand and respond to toddler's negative emotional expression. Specific questions for the study were as follows. 1. How do toddlers express their negative emotions to teachers and peers in a child-care center? 2. How do toddlers express their negative emotions to their mother in home? The study was carried out as a qualitative study with in-depth interviews, observations. Participants were a 29-months-old toddler(male) enrolled in a child-care center and two of his teachers, nine peers in his classroom and his mother. Data were collected for 9 weeks from October to December, 2005. Each observation lasted for two hours during greeting time, snack time, free play time and circle time at the child-care center. In addition, the toddler's emotional expression with mother was observed for two hours as he was eating, talking, playing etc. through the daily life in home. A total of 8 observations at the child-care center and 8 observations at home were made. The major findings of this study are as follows. 1. The teachers at the child-care center regarded the child's negative emotion as a sign of his immaturity in social, language, and communication skills. So teachers thought toddler's negative emotional expression including crying, yelling, shouting and annoying had to be educated and controlled. They tried to teach ways to suppress and control his negative emotion through the daily life in child-care center. 2. The child used negative emotional expression to secure his position among peers in a child-care center. Negative emotional expression was his means of showing himself to occupy toys, playground and teacher's affection among peers. 3. The toddler was free to express his negative emotions to mother because it was regarded as representing what he thinks and feels. Since negative emotion was accepted as natural self-expression in home, the toddler indicated plentiful negative emotion such as anger, jealousy, fear, regret, depression and he communicated and interacted to mother with various negative emotions. Also the mother thought that the child's negative emotions often appeared when he intended to be independent. 4. Toddler's negative expression was often converted to positive emotion as a result of participating in fun plays physically with his mother. The result of this research provide meaningful information for teachers of young children and parents to improve the quality of interacting and educating by considering and understanding toddler's negative emotional expression.

영아의 양육지원을 위한 정책 비교 : 한국·스웨덴·일본을 중심으로

곽승주(Seung Ju, Kwak),강유선(Yu Sun, Kang) 성신여자대학교 교육문제연구소 2007 교육연구 Vol.41 No.-

본 연구는 우리나라 영아기 자녀양육지원 정책의 현황 및 문제점과 대책을 모색하고자 자녀양육지원 정책의 모범 국가인 스웨덴과 우리나라와 유사한 사회·문화적 배경 및 행정체제를 가진 일본의 영아 양육지원 정책을 고찰하였다. 그 결과 영아기 자녀양육을 위한 보육정책의 방향은 부모와 영아의 긍정적 정서관계 돕는 가정중심의 지원으로 정책화되어야 하며, 이를 위해 노동시장에서의 모성 및 가족을 지원하는 고용정책이 요구된다. 또한 영아의 양육을 위한 가족정책 측면에서는 보편주의에 입각하여 저소득층 뿐 아니라 보다 많은 가정에 사회·경제적 지원이 제공될 수 있도록 공적지원의 대상범위를 확대해야 할 것이다. 이를 위해 정부는 자녀수당이나 가족수당 등 보편적이고 질 높은 영아양육을 지원할 수 있는 법적·제도적 기반을 모색하여야 할 것이다. This study will examine the current situation and problems with South Korea’s policies in support of infant-care, as well as analyze infant-care policies of other nations to find suggestions to propose for improving the quality infant-care policies in South Korea. The proposed policy reforms to improve the support for infant care are listed below. First, the "nurture policy" for rearing of infants must focus on the socio-economic conditions surrounding the infant and the family. Instead of supporting a surrogate nurture method of infant rearing, the policy should be a "family-friendly"approach, which supports the rearing of the child by his/her parent. Second, labor policies must work towards promoting employment policy in support of families and mothers and providing flexible work schedules for female workers. Support for infant care is not only limited to mothers or infants, but it is also very closely related to the labor market and employment policies. Therefore, a policy that actively prosecutes the violation of and supports the compliance of labor laws is necessary. For this purpose, the national government must establish an executive structure with legislative and administrative powers to penalize the violation of or to enforce compliance of employment laws as well as establish an incentive system to promote compliance in order to forcefully implement the maternity system. Third, policy in support of infant care should expand the social and economic support through child payment or family payment that is given to families with infants by introducing a universal infant care system. Fourth, support for infant care must be approached with an over-arching policy encompassing the parent and child as well as the family. For this to be realized the different departments in government must coordinate and work very close together. Furthermore, infant care support policy must be established and implemented in a coordinated effort with the departments supporting women, child, labor, education, and other governmental agencies related to these types of issues. Also, it is important that the established policies be disseminated through media, books, advertisements and campaigns so that the people will understand the policies and the justifications for them. Finally, through the mutual agreement amongst the citizenry on the system, the gap between the system and reality can be narrowed so that the whole society can participate in improving the quality of the infant care system.

가정과 어린이집에서 나타나는 2세 영아의 부정적 정서표현 및 조절에 관한 문화기술적 탐구

곽승주(Kwak Seung-Ju) 한국열린유아교육학회 2009 열린유아교육연구 Vol.14 No.6

본 연구의 목적은 가정과 어린이집의 일상에서 나타나는 2세 영아의 부정적 정서가 어떠한 요인과 맥락 속에서 나타나고 있으며 상황적 맥락에 따라 어떻게 변화되고 조절되는지를 고찰하는 것이다. 이러한 탐구를 통해 영아의 부정적 정서표현 및 조절양상에 대한 심층적 이해를 구함으로써 가정과 어린이집에서 영아와 어머니, 교사 간의 상호작용이 보다 긍정적으로 이루어질수 있도록 하는데 그 목적이 있다. 이를 위해 문화기술적인 방법으로 2세 영아 3명과 영아들의 어머니, 담임교사 4명의 생활을 가정과 어린이집에서 참여관찰하고 심층면담 하였다. 그 결과 영아는 부모나 교사의 정서적 관심을 독점하고자 하는 맥락에서 부정적 정서를 표출하였으며 이러한 상황에서 감정분출이나 조절된 신호보내기를 통하여 정서를 조절하는 것으로 나타났다. 놀이욕구가 충족되지 못하는 상황에서는 대안선택이나 정서이해받기 등 소통과 이해를 통한 조율이나 감정억제 및 보류를 통하여 정서를 조절하는 경향이 있었다. 또한 자율성 및 주도성을 발휘하지 못하는 경우에는 고집 피우기나 목표수정하기 등을 통해 활동에 참여하거나 성인의 안내와 지시에 따르면서 부정적 정서를 조절해 나갔다. 이외 어머니나 교사로부터 거부당하거나 인정받지 못하는 상황에서는 정서적 관계회복을 위한 보상행동이나 회피행동을 통해 부정적 정서를 완화하는 경향이 있었다. The purpose of this study is to investigate the context which gives rise to the negative emotions of two-year-old children shown usually at home and child care center, and to understand how their negative emotional expression and regulation are changed or adjusted in accordance with circumstantial contexts. The study was carried out as a qualitative study with in-depth interviews and observations. Participants were 3 two-year-old children and 4 teachers in a child care center, and the children's mothers at home. The findings of this study indicated that when children demanded all the emotional attention, they tended to control themselves through strategies at home such as getting angry and showing negative emotion constantly. On the other hand, at the child care center, they tried to repress and conceal their emotions. When the desire to play was not fully satisfied at home, the negative emotions of children were alleviated and controlled as either children selected various options or their were emotions understood by mother. At the child care center, children controlled their negative emotions and were induced to express themselves in words. In the cases in which children' self-determining capability and leadership were repressed, they tended to alleviate their negative emotions through insisting on what they wanted and carrying through their willingness to participate and they controlled themselves by following the instructions mother and teacher. When ignored and rejected by mother or teachers, children tried to convert their negative images by carrying out actions that were in contrast with those rejected by mother and teacher, and also children were likely to become timid and reclusive as responding to negative emotions.

Which Patients Are a Better Candidate of Laparoscopic Repair in Obturator Hernia Patients?

Jae Seung Kwak,이상억,Si Min Park,Seung Jae Lee,Seong Uk Kwon,In Eui Bae,Nak Song Sung,Ju Ik Moon,윤대성,In Seok Choi,Won Jun Choi 대한내시경복강경외과학회 2020 Journal of Minimally Invasive Surgery Vol.23 No.2

Purpose: Obturator hernia is a difficult disease to diagnose. If a surgical treatment is delayed in obturator hernia, a bowel resection may be required due to strangulation. The surgical treatment of this disease is to use a classical laparotomy. Recently, the laparoscopic approach has been reported and reviewed for efficiency. We checked the indicators that determine the most appropriate surgical method according to the patient's condition. Methods: In the study, a single-institution, retrospective analysis of surgical patients undergoing an obturator hernia surgery between 2003 and 2018 was performed. The patients were divided into a laparoscopic group (5 patients underwent laparoscopic repair; no intestinal resection) and an open group (13 patients who underwent open repair; 10 with and 3 without intestinal resection). The outcomes were compared between the groups. We analyzed the relevant factors that could predict the proper method of surgery. Results: A total 18 patients were included in the study. All patients were female, with body mass index (BMI) of under 21kg/m2. Of the various factors, only the WBC and CRP counts were the factors that had shown significant differences between the two groups. It is noted that patients with open surgery had a higher WBC counts (10406 versus 6520 /㎕; p=0.011) and CRP counts (7.84 vs. 0.32 mg/dl; p=0.027). Conclusion: Obturator hernia can be treated with a laparoscopic surgery.The choice of surgical treatment can be considered in advance through the review of the patient’s WBC count or CRP count.