스위치 커패시터 回路를 利用한 移相器의 設計

崔高峰,李健一 경북대학교 공과대학 1982 工大硏究誌 Vol.11 No.-

In this paper, a phase shifter using switched capacitor filters, switched capacitor PLL and switched capacitor weighted summer cirucits was designed. The available phase variation of it was 90 degrees, and it can be used at audio frequency level. The total harmonic distortion of the output wave was less than 8%, and especially above the 60 Hz, it was less than 2%. Overall experimental circuits of this paper can be implemented to one-chip IC.

분만손상

김태승,황건성,김주학 대한골절학회 2003 대한골절학회지 Vol.16 No.2

서론 : 분만손상이란 진통이나 분만기간 중에 발생될 수 있는 태아에게 해로운 모든 조건을 말한다. 이러한 손상에는 저 산소증으로 인한 뇌손상과, 기계적인 요소에 의한 골절, 신경마비, 두개내 혈종 및 복부손상 등을 포함하고 있다. 분만손상을 야기시킬 수 있는 위험 요인으로는 둔위분만, 감자분만, 아두골반 불균형, 난산, 과체중 등이 있으나 최근에는 산전관리 및 분만방법의 개선, 그리고 제왕절개술의 증가추세로 분만손상율은 감소를 보이고 있다. 정형외과 영역에서의 분만손상은 쇄골 골절, 상완골 골절, 상완 신경총손상, 대퇴골 골절 등이 있으며, 이에 본 병원에서는 최근 11년간 경험한 분만손상에 대해 연구 분석하였다. 대상 및 방법 : 1991년1월부터 2001년 12월까지 한양대의료원 서울병원에서 경험한 분만손상중 두개 내외의 혈종과 뇌신경손상 복부손상을 제외한 사지에 발생된 골절, 신경손상 환자 17명(남자 9명, 여자 8명), 20례를 대상으로 하였다. 두개 내외의 혈종과 뇌신경손상, 복부손상은 제외하였으며, 지료기록지를 조사하여 분만손상에 대한 자료를 얻었다. 결과 : 본 병원에서 경험한 분만손상 중 사지에 발생한 골절, 신경손상은 쇄골 골절 9례, 대퇴골 골절 3례, 상완골 골절 1례, 상완 신경총손상 6례, 원위대퇴골 골단분리증 1례이었다. 쇄골 골절 환아는 재태기간 40-42주사이에 분만되었으며, 신생아의 평균 체중은 4.25 ㎏으로 신생아체중 표준치에 비해 높았으며, 상완 신경총손상 환아 역시 재태기간 40-42주에 분만되었고, 평균 체중 4.42 ㎏으로 높았다. 대퇴골 골절 3례는 모두 둔위로 인한 제왕절개술 분만시에 발생하였고, 이들 중 1례는 좌골부결합체 (ischiopagus)로 태어났다. 원위대퇴골단 분리증 분리손상은 초기에는 간과되었으나, 시간이 경과하면서 현저한 골막반응을 나타내어 통해 분만손상으로 진단되었다. 결론 : 쇄골 골절과 상완 신경총손상은 과체중과 매우 관련이 있다고 할 수 있겠으며, 대퇴골골절은 둔위와 관련하여 제왕절개술시의 분만술기와 관계있다고 할 수 있겠다. 또, 마비증상은 상완 신경총 손상이나 골절로 인한 가성마비로서 나타날 수 있기 때문에 이에 대해 주의깊게 관찰해야 되겠다.무엇보다도 분만손상은 과체중과 관련된 경우가 많으므로, 초음파 검사 또는 산전 진단 방법을 통해 과체중으로 분만되는 것을 지양하여 분만손상을 줄이는 것이 필요하다 하겠다. Purpose : Birth injury is any condition that affects the adversely during the labor of delivery. These traumatic injuries are subdivided further into those from hypoxia and mechanical factors. Risk factor of birth injuries have been reported to breech presentation, forcep delivery, cephalopelvic desproportion dystocia, and high birth weight. But, because of preterm care and development of delivery method and Cesarian section, recently the rate of birth injury was decreasing and the articles about birth injuries in orthopaedic fields have not been much. We analyzed the data about birth injuries occurred during recent 11 years. Materials and Methods : We reviewed the charts and patients the 17 patients (20 cases) of birth injuries including fracture, nerve injury during the delivery at Hanyang University hospital from Jan. 1991 to Dec. 2001. But, we excluded birth injury of head and abdomen. Results : The number of fractures and nerve injuries on extrimities in our hospital were clavicle fracture 9 cases, brachial plexus injury 6 cases, femur fracture 3 cases, separation of distal remoral epiphysis I case, humerus fracture I case. Patients of clavicle fracture were born at mean intrauterine period 41.5 weeks and mean birth weight of the patients was 4.25 ㎏. Patients of brachial plexus injury were born at mean intrauterine period 39.5 weeks and mean birth weight of the patients was 4.42㎏. Three cases of femoral fracture were all due to breech position while cesarean operartion and one of these cases were born were as ishiophagus. We found the distal femoral epiphyseal separation injury missed initially and diagnosed a kind of birth injuries through remarkable periosteal reaction. Conclusion : The birth injuries including clavicle fracture and brachial plexus injury are highly related to high birth weight at birth and the femur fractures are related to delivery maneuver in C-section and breech delivery. Strict observation and monitoring are required because occasionally the paralysis might be the sign of brachial plexus injury or pseudoparalysis due to fracture. By the adequate preterm care or preterm ultrasound check up, high weight delivery could be avoided and then the birth injury must be reduced.

정신분열증 환자의 자아 방어기제 연구 : By the Korean Defense Mechanism Test Based on the Traditional Proverbs 전래의 속담을 기초로 한 한국형 자아 방어기제에 의한

이인길,이근후 大韓神經精神醫學會 1991 신경정신의학 Vol.30 No.1

This study was conducted to see the difference of defense mechanisms among normal control, acute and chronic schizophrenias with paranoid subtype using korean defense mechanism test based on the traditional proverbs. The results were as follows ; 1) Projection, denial, rationalization, displacement, acting out, passive-aggressive behavior, regression and brag were increased in chronic schizophrenics compared to control group, but sublimation was decreased in chronic schizophrenics compared to control group. 2) Projection, denial, somatization and rationalization were increased on acute schizophrenics compared to control group. 3) There was no significant difference between the acute schizophrenic patients and the chronic schizophrnic patients in all defense mechanisms.

Surfactant Assisted Growth of Nanostructured Tin oxide films for gas sensing applications

Kamalpreet Khun Khun,Aman Mahajan,R.K Bedi 대한금속·재료학회 2011 ELECTRONIC MATERIALS LETTERS Vol.7 No.4

Porous nanostructured SnO2 films have been prepared using an ultrasonic spray pyrolysis technique in conjunction with cationic, anionic and non ionic surfactants namely CTAB (Cetyl trimethyl ammonium bromide),SDS (sodium dodecyl sulphate) and PEG (polyethylene glycol) respectively. The effect of surfactants on the structural, electrical, optical and gas sensing properties of SnO2 films were investigated by using different techniques such as X-ray diffraction (XRD), Field emission scanning electroscope microscopy (FESEM), two probe technique and Photoluminiscence (PL) studies. The results reveal that the addition of surfactants in the precursor solutions leads to reduction in crystallite size with significant changes in porosity of SnO2 films. PL studies of the films show emissions in the visible region which exhibit changes in the intensities upon variation of surfactants in the precursor solutions. The prepared films were tested for their sensing behaviour towards chlorine and the results reveal that the films prepared in conjunction with cationic surfactant CTAB exhibits a sensing response of 53.5% towards 20 ppm chlorine at a low operating temperature of 150°C.

Augmentation Rhinoplasty with Silicone Implant

Khun Kheang,Eun Soo Park,Seung Min Nam,Ho Seong Shin,Sung Gyun Jung,Yong Bae Kim 순천향대학교 순천향의학연구소 2009 Journal of Soonchunhyang Medical Science Vol.15 No.1

Augmentation rhinoplasty in the Asian patient requires an understanding of his or her aesthetic goals which often differ from that of a Caucasian patient. Asian Patient frequently desire dorsal augmentation and tip projection. To accomplish these changes, the surgeon must take into account the typical characteristic of the Asian nose. these include thick skin, abundant subcutaneous soft tissue, weak lower lateral cartilage, and a relative paucity of septal cartilage. Because the Asian nose has relatively weak underlying structural support and a thick overlying soft tissue skin envelope, the surgeon may find a structural approach to Asian rhinoplasty useful to achieve a refined dorsum and tip. While various autologous and alloplastic materials are available for use in this procedure, there remains controversy regarding which material is best. A number of materials, both biologic and alloplastic, have been used for nasal augmentation. Although biologic bone and cartilage grafts are associated with lower infection rates, they are also associated with long-term resorption and donor-site morbidity. Silicone nasal augmentation is a safe and effective procedure when used for moderate increases in nasal height. Contrary to previous reports, this series showed no associated infection. If the implant is shaped appropriately to the patient's nasal phenotype, the risk of extrusion may be reduced, Improved reporting of silicone implant failures and follow-up times in future studies are needed to better define specific guidelines for the use of these materials.

Slenderness limit for SSTT-confined HSC column

Khun, Ma Chau,Awang, Abdullah Zawawi,Omar, Wahid Techno-Press 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.50 No.2

Due to the confinement effects, Steel-Straps Tensioning Technique (SSTT) can significantly enhance the strength and ductility of high-strength concrete (HSC) members (Moghaddam et al. 2008). However, the enhancement especially in strength may result in slender member and more susceptible to instability (Jiang and Teng 2012a). This instability is particularly significant in HSC member as it inherent the brittle nature of the material (Galano et al. 2008). The current slenderness limit expression used in the design is mainly derived from the experiment and analysis results based on Normal strength concrete (NSC) column and therefore the direct application of these slenderness limit expressions to the HSC column is being questioned. Besides, a particular slenderness limit for the SSTT-confined HSC column which incorporated the pre-tensioned force and multilayers effects is not yet available. Hence, an analytical study was carried out in the view of developing a simple equation in order to determine the slenderness limit for HSC column confined with SSTT. Based on the analytical results, it was concluded that the existing slenderness limit expressions used in the design are appropriate for neither HSC columns nor SSTT-confined HSC columns. In this paper, a slenderness limit expression which has incorporated the SSTT-confinement effects is proposed. The proposed expression can also be applied to unconfined HSC columns.

Computation of structural intensity for plates with multiple cutouts

Khun, M.S.,Lee, H.P.,Lim, S.P. Techno-Press 2003 Structural Engineering and Mechanics, An Int'l Jou Vol.16 No.5

The structural intensity fields of rectangular plates with single cutout and multiple cutouts are studied. The main objective is to examine the effect of the presence of cutouts on the flow pattern of vibrational energy from the source to the sink on a rectangular plate. The computation of the structural intensity is carried out using the finite element method. The magnitude of energy flow is significantly larger at the edges on the plate near the cutout boundary parallel to the energy flow. The effects of cutouts with different shape and size at different positions on structural intensity of a rectangular plate are presented and discussed. A case study on a plate with two cutouts is also presented.

Real-Time Rendering of Snow Accumulation and Melt Under Wind and Light

Jae-Khun Chang,Seung-Taek Ryoo 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.12

Snow is a common natural phenomenon that is frequently observed in winter. To simulate the effect of snow accumulation and melt, we generate exposure map from calculating occluding and shadow area using depth map. For simulating snow accumulation, we generate snow accumulated map using dispersed wind direction and occluder slope. We use light map calculating attenuation with distance on light source for simulating snow melt. To render snow in real-time, we use vertex displacement according to snow accumulation and melt. Also, we represent snow diffuse effect using perlin noise and snow boundary using stochastic sampling.

전부하 제어 펌프에 의한 박동형 펌프의 박출량 변화 평가

김건형(Khun-hyeung Kim),강성민(Seong-min Kang),최성욱(Seong-wook Choi) 대한기계학회 2020 대한기계학회 춘추학술대회 Vol.2020 No.12

New Horizons in Enclosure Studies: Parliamentary Enclosure, Common Right, and 'Open' and 'Close' Parishes in Britain, 1700-1850

Byung Khun Song 서울대학교 경제연구소 1998 經濟論集 Vol.37 No.3

The first charge on the labourers' ten shillings was house rent. Most of the cottages belonged to small tradesmen in the market town and the weekly rents ranged from one shilling to half a crown. Some labourers in other villages worked on farms or estates where they had their cottages rent free, for 'Stands to Reason,' they said, 'they've allus got to do just what they be told, or out they goes, neck and crop, bag and baggage.' A shilling, or even two shillings a week, they felt, was not too much to pay for the freedom to live and vote as they liked and to go to church or chapel or neither as they preferred.