• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제39권4호
• /
• pp.188-192
• /
• 2013

Post-traumatic anterior open bite can occur as a result of broken balance among the masticatory muscles. The superior hyoid muscle group retracts the mandible downward and contributes to the anterior open bite. Denervation of the digastric muscle by injection of botulinum toxin type A (BTX-A) can reduce the power of the digastric muscle and help to resolve the post-traumatic anterior open bite. A patient with a bilateral angle fracture had an anterior open bite even after undergoing three operations under general anesthesia and rubber traction. Although the open bite showed some improvement by the repeated operation, the occlusion was still unstable six weeks after the initial treatment. To eliminate the residual anterior open bite, BTX-A was injected into the anterior belly of the digastric muscle. Following injection of BTX-A, the anterior open bite showed immediate improvement. Complication and relapse were not observed during follow-up. Long-standing post-traumatic open bite could be successfully corrected by injection of BTX-A into the anterior belly of the digastric muscle without complication.

• 한국환경생태학회지
• /
• 제34권2호
• /
• pp.121-129
• /
• 2020

본 연구는 강원도 원주시에 설치된 사방댐을 대상으로 장마 전·후의 자료를 비교·분석하여 사방댐에 의한 저서성 대형무척추 동물의 군집 변화를 파악하고자 하였다. 조사시기는 2019년 3월부터 9월까지 총 4회 조사를 실시하였으며, 조사지점은 불투과형 사방댐(전석), 투과형 사방댐(버트리스), 대조지역을 선정하여 사방댐을 기준으로 상류 2지점, 하류 2지점을 조사하였다. 유속은 불투과형, 투과형, 대조지역의 지점에서 대부분 증가하였으며, 불투과형은 St. 3에서 장마 이후 감소하는 것으로 나타났다. 저서성 대형무척추동물의 종수 및 개체수는 장마 이후 대부분 감소하는 것으로 나타났으며, 투과형과 대조지역의 개체수 감소율은 전석에 비해 비교적 유사한 것으로 나타났다. EPT 그룹의 종수 및 개체수는 장마 이후 대부분 감소하는 것으로 나타났다. 유사도 분석 결과, 장마 이전에는 불투과형 및 투과형이 대조지역과 38.4%로 구분되었으나, 장마 이후에는 투과형과 대조지역이 불투과형과 51.3%로 구분되었다. PCA 분석 결과, Axis 1을 기준으로 불투과형은 장마 전·후로 양의 값을 나타내었으며, 투과형과 대조지역은 장마 전·후 음의 값을 나타내어 불투과형 보다는 투과형이 대조지역과 상관성이 높은 것으로 분석되었다. EPT 그룹은 불투과형에서 하루살이목, 투과형과 대조지역에서 날도래목이 분포하는 것으로 분석되었다. 본 연구결과, 사방댐 설치는 저서성 대형무척추동물 군집에 변화를 초래할 수 있으며, 불투과형 보다는 상대적으로 투과형이 대조지역과 장마 이후 군집 차이가 적은 것으로 분석되었다.

• 한국생산제조학회지
• /
• 제21권1호
• /
• pp.21-25
• /
• 2012

In this study, the safest model can be selected by the simulation result of structural safety analysis according to the shape of impact bar affected at side door of automobile. The open sectional model of semicircle type has the lowest deformation and stress among 4 kinds of models. As the weight of this model has 30% in comparison with other models, it becomes most economical and stable. As the open sectional model of cap type the highest deformation and stress among 4 kinds of models, it becomes weakest. The closed models with circular and rectangular types has the stress far lower than cap type. The maximum deformation is shown at the center part of impact bar but the maximum stress occurs at the joint part between impact bar and frame.

• 대한산업공학회지
• /
• 제39권6호
• /
• pp.517-534
• /
• 2013

In this study, we propose the guideline with strategic model for new product development. To establish the guideline, 1) we classify several types of successful surveyed cases that achieved open innovation through applying crowdsourcing into new product development environment, 2) draw case maps using two or three axis with characteristics such as: step of product development process, crowdsourcing frequency, and product type of each case, 3) define the type of applying crowdsourcing into new product development environment based on case analysis results, and tabulate a crowdsourcing type based on the defined crowdsourcing type, 4) finally, suggest the guideline with multiple points of view which embrace type of crowd, community management, participation method, knowledge adoption method, and reward policy. Using the suggested guideline will help a company to design and establish open innovation in new business model related to product development area.

• Architectural research
• /
• 제8권2호
• /
• pp.11-16
• /
• 2006

The purpose of this study is to scrutinize the effect of office layouts and ambient office sounds on the performance of office workers involved with a proof-reading test (simple task). Twenty subjects, who were professional researchers and computer programmers, were from three different office layouts: 1) Nine subjects from a combined office type with open meeting places and closed individual offices; 2) five from an open office with rectangular individual workstations, and 3) six from an open office with triangular individual workstations. Architects and consultants working in the field of office have reported from interviews and their own observations that occupants' satisfaction differs as their office layouts vary although the sizes are the same. This finding leads to the hypothesis of this experiment. Proof-reading test results were obtained from three different office layouts (combined office type, rectangular and triangular individual workstations in open offices) under two different sound conditions (quiet background sound and ambient sound of their own workplace) for 10 minutes. The test analysis shows the mean test score of subjects from the triangular individual workstations in open offices is significantly different from the mean test scores of subjects from the combined office type and the rectangular individual workstations in open offices.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2005년도 ICCAS
• /
• pp.575-579
• /
• 2005

In this paper, the development of an IMM(Injection Molding Machine) controller is discussed. Presently, the Mold Close and Open Control Method of a toggle-type IMM is open-loop control. Through the development, a PC based control system was built instead of an existing controller and a closed-loop control replaced the previous control method by using PC based PLC. To control the nonlinear system of toggle type clamping unit, a fuzzy PI control algorithm was selected and it was programmed by an IL(Instruction List) and a LD(Ladder Diagram) on a PC based PLC. The application of fuzzy algorithm as the control method was also considered to change a control object like a mold replacement or an additional apparatus. For the development of an IMM controller, PC based PLC of PCI card type, distributed I/O modules with CANopen and Industrial PC and HMI (Human Machine Interface) software were used.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제52권9호
• /
• pp.468-474
• /
• 2003

This paper describes the development of an open frame type high power density switching converter. It is based on the active clamp forward converter with synchronous rectifier, and packaged by using the open frame and multi-layer printed circuit board (PCB) technology to achieve the higher power density. Furthermore, the windings of transformer and inductor are also realized by multi-layer PCB so that it also contributes to achieve higher power density. Through the experiment on the prototype converter of 50[W], it is confirmed that power density of 50[W/i$n_3$] and maximum efficiency of over 91[%] are obtained.

• 대한건축학회논문집:구조계
• /
• 제34권5호
• /
• pp.43-50
• /
• 2018

The temperature of underground water generally remains constant regardless of the season. therefore, it is possible to get plenty of energy if we use characteristics of underground water for both cooling and heating. This study evaluates efficiency of real size coaxial and U-tube type complex geothermal system which is combined with underground water well. This study also evaluates relative efficiency/adaptability through comparison with existing geothermal systems(vertical closed loop system, open loop system(SCW)). The heat exchange capacity of complex geothermal system according to temperature difference between circulating water and underground water shows very high significance by increasing proportionally. The temperature change of underground water according to injection energy, shows very high linear growth aspect as injection thermal volume heightens. As a result of evaluation of heat exchange volume between complex geothermal system and comparative geothermal system, coaxial type has 26.1 times greater efficiency than comparative vertical closed type and 2.8 times greater efficiency than SCW type. U-tube type has 26.5 tims greater efficiency than comparative vertical closed type and 2.8 times greater than SCW type as well. This means complex geothermal system has extremely outstanding performance.

• Korean Chemical Engineering Research
• /
• 제60권1호
• /
• pp.12-19
• /
• 2022

소형 이송형 고분자전해질 연료전지 (PEMFC)에 많이 사용되는 cathode 개방형 PEMFC 스택은 내구성이 약한 문제점이 있다. 13개의 셀로 이루어진 PEMFC 스택의 가속 내구성 평가를 통해 스택의 열화 원인을 찾고 cathode 개방형 스택의 내구성 향상에 기여하고자 하였다. Cathode가 대기에 개방되어 있고, 기밀 유지가 어려운 cathode 개방형 스택의 구조적 문제점 때문에 시동/정지 (SU/SD)시 수소/공기 경계가 형성되어 cathode를 열화시킨다. 본 연구에서는 cathode 개방형 스택에 SU/SD 1,800회 반복 후 초기 성능의 54%가 감소하여 비교적 짧은 시간에 내구성을 평가할 수 있었다. 스택 해체 후 각 셀을 2등분하여 성능분석하였다. 전체적으로 공기 유입이 용이한 anode 출구부 MEA가 유입부 MEA보다 전극 열화가 더 심해서 SU/SD시 수소/공기 경계 형성이 주요 열화 원인임을 확인했다.

• Ecology and Resilient Infrastructure
• /
• 제8권1호
• /
• pp.54-63
• /
• 2021

본 연구는 강원도 원주시에 3개의 사방댐이 연속적으로 설치된 지역을 대상으로 장마 전·후의 자료를 비교·분석하여 사방댐에 의한 저서성 대형무척추동물의 군집 변화를 파악하고자 하였다. 조사시기는 2019년 3월부터 9월까지 총 4회 조사를 실시하였으며, 조사지점은 불투과형이 연속적으로 설치된 지역과 투과형이 연속적으로 설치된 지역을 선정하였다. 불투과형, 투과형 사방댐 각각 상·하류로부터 총 8개의 지점을 선정하였다. 유속은 장마 이후 불투과형, 투과형 모두 대부분의 지점에서 증가하였으나, 불투과형은 투과형보다 상대적으로 유속의 변화가 큰 것으로 확인되었다. 저서성 대형무척추동물의 종수 및 개체수는 장마 이후 대부분의 지점에서 감소하는 것으로 나타났으며, 불투과형 상류지점이 상대적으로 종수 및 개체수가 높은 것으로 나타났다. 하루살이목-강도래목-날도래목 (EPT) 그룹 분석은 상대적으로 불투과형에서 하루살이목이 감소하였으며, 투과형에서 날도래목이 감소하였다. 유사도 분석 결과, 불투과형, 투과형 모두 장마 전·후가 구분되었으며, 투과형이 상대적으로 장마 전·후의 변화가 적은 것으로 분석되었다.