• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.442-445
• /
• 1997

A challenging activity in the manufacturing industry is to perform in real time the continuous monitoring of the process state, the situation assessment and identification of the problem on line and diagnosis of the cause and importance of the problem if he process does not work properly. This paper describes LAT(Ladder Analysis Tool) system for fault tree generation to improving the fault diagnosis of CNC machine tools. The system consists of 4 steps which can automatically ladder analysis from ladder diagram to two diagnosis function models. The two diagnostic models based on he ladder diagram is switching function model and step switching function model. This system tries to overcome diagnosis deficiencies present machine tool.

• Journal of Korean Critical Care Nursing
• /
• v.3 no.1
• /
• pp.1-13
• /
• 2010

Purpose: This study was designed to evaluate ICU nurses' clinical competence according to clinical ladder by job analysis tool for the evaluation tool development of clinical ladder development program, Methods: Data was collected using the ICU nurses job analysis tool from 148 ICU nurses who work for 6 ICUs of A hospital in S city, Results: The mean clinical competence score of the subjects was 3.03 on a 4 point scale, Competence score was increasing as ICU clinical ladder was higher (F=35.18, p<.001). Step_1 was the lowest and step_4 was higher than step_3 from Scheffe post hoc test, Result of multiple regression showed that ICU clinical ladder and ICU clinical nursing education explained 52.1% (F=38.83, p<.001) of ICU nurse's clinical competence. Conclusion: ICU nurses' clinical competence can be evaluated using ICU nurse's job analysis tool. Further researches is needed on job description according to clinical ladder for performance and evaluation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2002.04a
• /
• pp.48-52
• /
• 2002

The fault analysis of the CNC machine tool which is controlled sequentially by PLC is generally based on ladder diagram. When machine tool has faults, it takes a lot of operator's experiences and times to identify logical relationship because ladder diagram is a step structured language. Therefore the technologies of finding out fault reasons automatically is necessary. In this paper, the SFG(Switching Function Generator) system is developed to analysis fault reasons correctly. The SF(Switching Function) and SSF(Step Switching Function) generated from SFG based on ladder diagram are experimented to identify the performance of SFG.

• The Journal of the Acoustical Society of Korea
• /
• v.18 no.1
• /
• pp.16-24
• /
• 1999

Design of SAW ladder filters has been performed by a rather trial and error method, that is, by modifying the design variables step by step until designed performance of the filter satisfies given specifications. In this work, optimal design method has been developed that automatically determines the detailed pattern of the SAW ladder filter to meet the specification once desired performance is given. As a first step for the development, the analysis tool for the SAW ladder filter has been produced by means of the Smith equivalent circuit analysis technique, and its validity has been verified through comparison of its calculation result with experimental data. With the analysis tool, we have investigated the performance variation of the filter with the change of its design factors, and the result has led to the optimal design algorithm. Validity and efficiency of the algorithm has been checked through test design of several SAW ladder filter samples on the market.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.6 no.2
• /
• pp.225-231
• /
• 2010

This paper proposes the strategy of ladder trades in a symbol pool and simulates a performance of it on the Multicharts' system trading tool. The ladder trading strategy is based on a multi-entry strategy which is efficient for several symbols. A symbol pool is composed of verified stocks comprising KOSPI200 and 17 symbols are selected for an examination which equity is over 10 billion. From July to December in 2009, optimum parameters are searched and the results are delta is 4% and ladder is 5. When those parameters are adopted, the profit is 1,000,000 won as a single trade and the number of trade is 188. The next study is to modify a ladder shape for increasing probability and to find the difference of optimum parameters according to trading months.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.16 no.2
• /
• pp.8-13
• /
• 2007

The purpose of this study is to reduced the weight of ladder boom and to improve the manufactor process by the section modification. The Conventional model consists of integral section stiffener, while the proposed model consists of truss type stiffener to reduce the weight of ladder boom and wind effector. In the two analysis models, one is based on the single boom, and the other is based in the coupling model of two booms. We present the analysis results for the case when applying the weight, bending and twisting moment and wind pressure. Finally, a comparison between these results is presented to show the performance of our method.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.16 no.3
• /
• pp.96-102
• /
• 2007

An Optimal shape design of the boom system in high ladder vehicles is performed using 3-D finite element method (FEM). Results of structural analyses providing displacements, stresses are implemented for the optimum shape design. Lanzcos algorithm is used for the modal analysis in order to find natural frequencies. The optimal shape including cross sectional thickness and length of the boom system is controlled by the subproblem method besed on displacement and Von Mises stress. It is found that a plenty of materials can be saved by using shape design optimization in high ladder vehicles. It is also found that the natural frequency is increased until 6th mode and maintained similarly or decreased after 6th mode.

• Journal of Korean Academy of Nursing Administration
• /
• v.17 no.3
• /
• pp.301-314
• /
• 2011

Purpose: This study was a methodological research conducted to develop a clinical ladder system for operating nurses. Methods: Participants were 20 OR nurses, working in C Hospital, who had a mean tenure of 6 years and 10 months. Data collection consisted of 4 focus group interviews during May and June 2009. The content analysis method of Kim and Lee (1986) was used to analyze the data. Two clinical expert groups consisting of 16 nurses verified the content validity of the preliminary system from September 16 to 26, 2009 using Kim's tool (1999). Results: The final clinical ladder system consisted of goals, core values, and 4 domains of practice related to core values, which were defined as professional value, perioperative nursing practice, education/research, and collaboration/leadership. Eleven nursing competencies and 44 behavior indicators were included in accordance with the 4-step ladder. The 4 operation systems for the clinical ladder system were the promotion system, continuous learning system, reward system, and support system. Conclusion: The results indicate that nursing managers need to pay more attention to developing a clinical ladder system for nurses.

• Journal of the Korean Society of Safety
• /
• v.35 no.5
• /
• pp.86-94
• /
• 2020

Portable ladders are normally used both as an access tool for ascending and descending and as a platform for high place work. Though convenient, such usages make the portable ladders vulnerable to fall accidents. For this reason, many safety systems such as regulations and certifications are implemented to prevent fall accidents of portable ladders. However, nevertheless of those safety systems in Korea, annual death tolls of ladder fall accidents has remained high, and which suggests modification and improvement of the portable ladder related safety systems in Korea. The aim of this study is to propose directions for improving safety systems to effectively prevent fall accidents of portable ladders. To this end, comparative analysis on safety systems implemented in Korea and other countries including Japan, USA and UK are conducted to investigate the problems of Korean safety systems. Based on the analysis, limitations of Korean safety systems to prevent ladder fall accidents are discussed and tasks to overcome the limitations are proposed. Once implemented, the proposed tasks would contribute to prevent ladder fall accidents effectively.

• The Journal of the Acoustical Society of Korea
• /
• v.21 no.1
• /
• pp.47-55
• /
• 2002

This paper proposes a new improved lumped element equivalent circuit analysis method to analyze withdrawal weighted SAW resonators of irregular electrode configurations, which enables to calculate the frequency response of withdrawal weighted SAW resonators. This method has led to the derivation of Smith equivalent circuit's y-parameters for a single ground electrode and formulated the resonator's admittance by calculating the total current into an IDT assembly. To illustrate the effectiveness of the technique, this method was applied to the design of a simple ladder filter and the change of the filter performance was investigated in relation to the weighting of the series and parallel resonators, respectively. The results shows that the withdrawal weighted resonator ladder filters provide better performance in their bandwidth and transition characteristics than normal ones. This new equivalent circuit analysis method can also serve as a better tool to design and analyze general SAW resonator filters.