• Restorative Dentistry and Endodontics
• /
• 제45권2호
• /
• pp.22.1-22.10
• /
• 2020

Objectives: This study investigated the influence of glide path size and operating kinetics on the time to reach the working length and the fracture resistance of Twisted File (TF) and Endostar E3 files. Materials and Methods: A total of 120 mandibular single-rooted premolars were selected. Two methods of kinetic motion (TF adaptive and continuous rotary motion) and file systems (TF and Endostar E3) were employed. The files were used in root canals prepared to apical glide path sizes of 15, 20, and 25. The time taken to reach the working length and the number of canals used before the instrument deformed or fractured were noted. Fractured instruments were examined with scanning electron microscopy. Results: The TF system took significantly more time to reach the working length than the Endostar E3 system. Both systems required significantly more time to reach the working length at the size 15 glide path than at sizes 20 and 25. A greater number of TFs than Endostar E3 files exhibited deformation, and a higher incidence of instrument deformation was observed in adaptive than in continuous rotary motion; more deformation was also observed with the size 15 glide path. One TF was fractured while undergoing adaptive motion. Conclusions: No significant difference was observed between continuous rotary and adaptive motion. The TF system and adaptive motion were associated with a higher incidence of deformation and fracture. Apical glide path sizes of 20 and 25 required significantly less time to reach the working length than size 15.

• 한국융합학회논문지
• /
• 제13권1호
• /
• pp.131-139
• /
• 2022

본 연구는 장애인 거주시설에 근무하고 있는 물리치료사들의 직무 만족이 직무몰입에 미치는 영향과 이직요인을 알아보았다. 장애인 거주시설에 근무하는 물리치료사 122명을 대상으로 직무 만족도(23문항)와 조직 몰입도(11문항)를 알아보았고 이직 요인 9문항, 일반적인 특성 7문항으로 구성된 구조화된 설문지를 이용한 조사였다. 연구결과, 장애인 거주시설에 근무하고 있는 물리치료사의 직무 만족은 3.16, 조직 몰입도는 3.29로 중간 정도로 나타났다. 직무만족도 중 자부심, 상사 및 복지제도, 의사소통, 동료 요소가 정서적 몰입도에 영향을 주는 것으로 나타났다(p<.001). 장애인 거주시설에서 근무하는 물리치료사들은 상사와 동료와의 불협화음, 근무환경 열악, 급여문제, 과다한 업무를 이직 요인으로 지적하였다. 장애인 거주시설에 근무하는 물리치료사들의 조직 몰입을 높이기 위하여서는 그들의 업무에 대한 존중과 상사와 동료와의 관계 개선이 필요한 것으로 보인다.

• 한국콘텐츠학회논문지
• /
• 제15권4호
• /
• pp.188-196
• /
• 2015

경찰에게 과학수사는 수사, 형사, 조사 등 범죄수사의 여러 분야에 도구로서 활용 인식되어 왔기 때문에 지금까지 필요함에도 불구하고 중심적인 역할과 위치를 차지하지 못한 것이 사실이다. 이에 본 연구는 경찰의 과학수사 활동에 대한 중요성을 인식하고, 현재 과학수사에 있어서 관련 현황과 과학수사를 위한 지원수준을 살펴보고 문제점을 검토하였다. 이를 토대로 현실적 한계 속에서 어떠한 방식으로 과학수사 활동의 효율성을 향상시킬 수 있을 것인가를 모색하기 위해 근무제도의 발전방안을 논의하고자 하였다. 현재 경찰의 과학수사 활동이 직면하고 있는 문제점으로는 무엇보다 검거중심의 인력 운영에 따른 만성적인 인력부족 현상이었다. 이에 현실적인 제약 내에서 과학수사요원의 활동을 효율적으로 변화시킬 수 있는 방안을 모색하였다. 첫째, 근무체제의 변화가 필요하며, 중 장기적인 관점에서 지휘체제의 개편으로 광역 과학수사체제의 시행이 필요하다. 둘째, 과학수사의 전문성을 확보할 수 있도록 과학수사 경과의 신설이다. 셋째, 과학수사 특기제도가 개선되어야 한다. 넷째, 과학수사의 역량 강화를 위하여 R&D 조직이 구축되어야 할 것이다.

• 수산해양기술연구
• /
• 제41권2호
• /
• pp.101-106
• /
• 2005

This study was carried out to observe the underwater geometry of the anchovy boat seine by two fishing operation systems. One was a traditional operation system that used a fish detecting boat, another was a new operation system that used the same fishing gear with floats and sinkers in comparison with a fish detecting boat. Vertical opening of the fishing gear that used a casting net, working depth of each part of the fishing gear that used a new operation system was almost canstant, but was gradually shallow in a traditional operation system. Just before hauling net, working depth of each part of the fishing gear that used a new operation system was maintained stable, but was vertically unstable in a traditional operation system because as rear part of the fishing gear was risen up the upper layer. Just after hauling net, working depth of the fishing gear that used a new operation system was also maintained stable, and then anchovy school could be lead to bag net.

• 대한기계학회논문집B
• /
• 제26권9호
• /
• pp.1241-1248
• /
• 2002

Performance extension of the absorption refrigerator with LiBr solution is often faced to operate very close to the crystallization limit. Especially in the development of an air-cooled cycle, the crystallization of working solution in the system is a very difficult problem to overcome. This paper describes the cycle of hot water driven absorption system using a new working absorption solution instead of LiBr solution to improve the efficiency. In this study, we found out the characteristics of new working absorption solution through the cycle simulation and compared LiBr solution to evaluate. The effect of cooling water temperature, weak solution flow rate, hot water temperature and hot water flow rate were also examined. The COP is increased 22% higher in the case of LiBr＋Li1＋LiC1＋LiNO$_3$＋$H_2O$, 2% LiBr＋HO(CH$_2$)$_3$OH＋$H_2O$ than that of LiBr solution for the same operation condition.

• 제어로봇시스템학회논문지
• /
• 제10권7호
• /
• pp.643-648
• /
• 2004

Most of shoes manufacturing processes are not yet automated, which puts restrictions on the increase of productivity. Among them, adhesive application processes particularly are holding the most workers and working hours. In addition, its working conditions are very poor due to the toxicity of adhesive agents. In case of automating adhesive application processes by using robots, the robot teaching by playback is difficult to produce high productivity because the kinds of shoes to be taught mount up to several thousands. Therefore, it is essential to generate the robot working paths automatically according to the kind, the size, and the right and left of shoes, and also to teach them to the robot automatically. This study deals with automated adhesive spraying to shoe outsoles and uppers by using a robot, and develops the program to generate three-dimensional robot working paths off-line based on CAD data. First, the three-dimensional data of an outsole outline or an upper profiling line are extracted from the two-dimensional CAD drawing file or the three-dimensional scanner. Next, based on the extracted data and the nozzle conditions for adhesive spraying, a robot working path is generated automatically. This research work is the core in automating adhesive spraying processes, and will do much for increasing productivity of shoes manufacturing.

• 동력기계공학회지
• /
• 제20권6호
• /
• pp.46-50
• /
• 2016

This study was carried out to investigate the effect of cold working on the tensile strength of Fe-26Mn-4Co-2Al damping alloy. ${\alpha}^{\prime}$ and ${\varepsilon}$-martensite were formed by cold working, and martensite was formed with the specific direction and surface relief. With the increasing degree of cold rolling, volume fraction of ${\alpha}^{\prime}$-martensite was increased, whereas the volume fraction of ${\varepsilon}$-martensite was decreased after rising to maximum value at specific lever of cold rolling. Tensile strength was linearly increased with an increasing of degree of cold rolling. Tensile strength was strongly affected to the volume fraction of ${\varepsilon}$-martensite formed by cold working, but the effect of volume fraction of ${\varepsilon}$-martensite on the tensile strength was not observed.

• 한국태양에너지학회:학술대회논문집
• /
• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
• /
• pp.68-73
• /
• 2011

An experimental study was conducted to investigate the thermal performance of a medium-temperature heat pipe against the charge amount of working fluid. The container and the wick of the heat pipe were made of stainless steel and the working fluid was Dowtherm-A for medium-temperature applications around $250^{\circ}C$. The diameter and length of the heat pipe were 25.4 mm and 1 m, respectively. The maximum thermal load was 1 kW and the working fluid charge ratio varied from 372% to 420%. The results showed that the thermal resistance ranged from 0.12 to $250^{\circ}C/W$ and the effective thermal conductance ranged from 7,703 to $8,898 W/m{\cdot}K$. Dry-out occurred for the heat pipe with 372% fill-charge at the heat load of 950 W, while the other heat pipes with higher charge amount did not encounter dry-out up to 1060 W.

• 한국농촌간호학회지
• /
• 제5권1호
• /
• pp.25-32
• /
• 2010

Purpose: The purpose of this study was to provide a fundamental data for improving nurses' working environment and securing quality of nursing care. Method: It was consisted of analyzing education system and employment status of nursing personnel, and focus group interviews in Cheju Island. Results: Total graduates were 4,139 by 2006 from two nursing schools in Cheju. Difficulties in working conditions from focal group interviews were classified into four categories; Lack of anonymity of nurses, the burden from performing nontraditional nursing roles due to shortage of physicians, irregularity of working schedule and too many night shifts for taking care of female colleague's condition related with pregnancy, and poor support for implementing and developing professional nursing. Conclusion: A survey revealing working condition of nursing personnel of all health care institutions in Cheju Island will provide the comparison between Cheju Island and other areas. It needs to cultivate the public opinion about the importance of quality of nursing care proceeded by the broad support for improving nurses' working environment. It is essential to support continuing education to bring professional nurses and establishing the system to utilize them to overcome the shortage of physicians in Cheju Island.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
• /
• pp.387-390
• /
• 1997

Grinding process takes a long time that grinding machine is setted properly. It is difficult for user to judge correctly the abnormal states generated in grinding process. Air grinding has to be reduced for the improvement of productivity. In addition, it is important to monitor the dressing and the grinding process so that the grinding working maintains optimal grinding conditions. In this study, the monitoring system using the acoustic emission is developed to monitor these processes continuously. This system was able to reduce the preparation as well as the machine setting time in grinding operation.