• 한국정밀공학회지
• /
• 제22권11호
• /
• pp.82-90
• /
• 2005

Recently, the in-line vision inspection has become the subject of growing research area in the visual control systems and robotic intelligent fields that are required exact three-dimensional pose. The objective of this article is to study the pc based in line visual inspection with the hand-eye structure. This paper suggests three dimensional structured light measuring principle and design method of laser sensor header. The hand-eye laser sensor have been studied for a long time. However, it is very difficult to perform kinematical analysis between laser sensor and robot because the complicated mathematical process are needed for the real environments. In this problem, this paper will propose auto-calibration concept. The detail process of this methodology will be described. A new thinning algorithm and constrained hough transform method is also explained in this paper. Consequently, the developed in-line inspection module demonstrate the successful operation with hole, gap, width or V edge.

• 한국안전학회지
• /
• 제5권1호
• /
• pp.31-39
• /
• 1990

In this paper, the influence of the table speed, metal removal rate and grinding fluid on long wheel workpiece contact zone at high effect grinding was investigated by theoretical analyses and measuring the temperature, and discussed by the temperature distribution in grinding surface layer. Main results obtained are as follows, 1) Rega.dless of the table speed, the temperature gap of the workpiece(heat influx) is about 6-8 times as high in dry condition as in wet condition. 2) Good grinding condition can be obtained owing to the effect of grinding fluid without any burning defect under the condition of the metal removal rate(1.0mm$^3$/mm.s) in case of wet grinding. 3) When the depth from the surface layer is about 1.25-1.5mm under the condition of the slow table speed, surface temperature goes up higher as the table speed slows down, because long contact time is laked at the surface layer. 4) In case of the same metal removal rate, the lower the table speed becomes, the higher the surface temperature is, because grinding depth has a far more influence on wheel workpiece contact zone than the table speed.

• 한국멀티미디어학회논문지
• /
• 제21권7호
• /
• pp.802-812
• /
• 2018

Recently, there are several active and vibrant studies on Realistic Media that try to provide the immersion and the presence by adding sensory effects to video. Because existing sensory effects on Realistic Media are produced through experts and automation programs on sensory effects, there is a limit to fill up the gap of user satisfaction which comes from the diversity of cybernauts. In this paper, we propose a method to improve the satisfaction with sensory effects by collecting and analyzing user's response information, and applying the result to the attributes of sensory effects. The proposed method allows you to produce the Sensory Effect Metadata effectively by analyzing users' biometric data and subjective satisfaction with realistic media experience, measuring the weighted value to revise the effects, and applying to the attribute of sensory effect. The experimental result shows that the proposed method improves the satisfaction with realistic content by generating the revised Sensory Effect Metadata in response to user's experiential feedback information.

• 대한간호학회지
• /
• 제34권2호
• /
• pp.225-234
• /
• 2004

Purpose: The purpose of this study was to develop a tool that measures the quality of nursing service, to measure the quality of nursing service perceived by consumers, and to identify the gaps between ideal and actual nursing services. Method: A questionnaire was developed and distributed to 300 people who had been hospitalized in one of six general hospitals with quality of nursing services in five provincial cities in Korea. For data analysis, the SPSS/WIN(ver 10.0) program was used. Result: The 20 attributes included in the instrument of quality of nursing service is abstracted into 2 factors: tangibility and intangibility. In quality analysis, 15 of 20 attributes are minus scores, meaning that those nursing services are perceived as generally low. However among the minus scores' attributes, only two attributes are significant statistically. Gaps between importance and performance of the nursing service exists in 19 among 20 attributes. Conclusion: Nursing service quality (performance-expectation) needs to be improved, and Gaps (importance-performance) reduced. In addition, a tool measuring nursing service quality has to be developed so nurses can deal successfully with the quality and gaps of nursing service perceived by consumers.

• 한국마린엔지니어링학회:학술대회논문집
• /
• 한국마린엔지니어링학회 2012년도 전기공동학술대회 논문집
• /
• pp.157-157
• /
• 2012

The Characteristics of the drag reduction of a square prism having a detached splitter plate at the wake side was investigated by measuring of fluid force on the square prism and by visualization of the field using PIV. The experimental parameters were the width ratios(H/B=0.5~1.5) of splitters to the prism width and the gap ratios (G/B=0~2) between the prism and the splitter plate. The drag reduction rate was increased with H/B, and was increased and decreased with G/B. The maximum drag reduction rate was represented by 24.2% at H/B=1.5 and G/B=0.5. The two vortices were generated by the splitter plate at the wake region of the prism. The direction of the vortex was clockwise at the upside of the splitter plate and counterclockwise at the downside.

• 유통과학연구
• /
• 제15권11호
• /
• pp.59-72
• /
• 2017

Purpose - This paper evaluated the efficiency performance of the three major maritime transport markets and examined the determinants of the performance. The firms' revenue fluctuates with the changes of the economic cycle; hence it is important for them to set up business strategies to improve efficiencies. A lack of efficiency measurements for shipping firms leads to a significant gap in determining their overall performance. Research design, data, and methodology - Each of DEA scores was adopted for the evaluation and panel regression was used to examine the impact of determinants on the performance. The analysis included 50 shipping firms from three maritime transport markets as follows; 15 firms of container liners, 18 firms of bulk carrier and 17 firms of tanker carriers, and its period was from 2010 to 2016. Results - In the CCR model, container liners were the highest, tanker carriers were the second, and bulk carriers were the lowest in operation efficiency and financial efficiency. By region, operation efficiency and financial efficiency was high in the order of America, Asia, and Europe. Conclusions - This study suggests business strategies for maritime transport companies based on the analytical results of determinants of operational and financial efficiency.

• 대한치과보철학회지
• /
• 제37권6호
• /
• pp.791-799
• /
• 1999

The purpose of this study was to investigate the displacements of cast framework by torch soldering and electric soldering techniques. Specimen had two cylinders and connecting bar that had sectioned with 0.3mm gap at mid point. 10 of total specimens were divided into two groups. In torch soldered group, soldering investment block was made and conventional torch solder-ing procedure was carried out. In electric soldered group, electric soldering was carried out on the master cast without soldering investment block by using electric soldering machine(Dentapunkt DP 7, Kulzer, Germany) After soldering procedure, three dimensional coordinates of two centroids of each cylinder were measured by three dimensional coordinate measuring machine. The intercentroidal displacement and global displacement were calculated and then, these values were compared and evaluated. The results were obtained as follows: 1. Intercentroidal distances of specimens decreased after both soldering procedures, and the decrease in intercentroidal distance was greater for torch soldered group than for electric soldered group 2. Global displacements of torch soldered group were greater than those of electric soldered group.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2006년도 춘계학술대회 논문집
• /
• pp.497-498
• /
• 2006

Tribological properties of a Magneto-Rheological(MR) fluid in a polishing process are studied. For this polishing process, abrasive wear model is proposed as a function of shear force, normal force and actual mean velocity of MR particles at workpiece surface. Experimental conditions are changed by varying the gap distance between workpiece and tool and the rotational speed of tool. From the experimental results, a modified Stribeck curve is obtained, and the friction coefficient turns out to have linear relationship with a modified Sommerfeld number. The validity of the wear model is supported by additional experiments performed for measuring material removal rates.

• Journal of Welding and Joining
• /
• 제28권3호
• /
• pp.73-78
• /
• 2010

The purpose of this study is to develop the control technology of the welding distortion caused by Auto NG-GTA(Narrow Gap-GTA) welding process at the STS 304 multi-pass butt weldment. Heat input model for Auto NG-GTA welding process was established and verified by measuring temperature change and molten pool shape at the bead-on-plate weldment. With the heat input model developed, the effect of tension load on the welding distortion at the STS 304 multi-pass butt weldment was evaluated using the thermo-elasto-plastic FE analysis. In accordance with FEA results, the angular distortion and transverse shrinkage sharply decreased with an increase in tension load. This result indicated that tensioning method was an effective countermeasure against the welding distortion of the STS 304 multi-pass butt weldment.

• 한국생산제조학회지
• /
• 제23권6호
• /
• pp.590-595
• /
• 2014

We have investigated anamorphic prism lenses with distortions of 0.3-0.5%. We designed the plastic triangular lens and confirmed the minimum resolution using MTF graphs. Also we confirmed that the SVGA optical system can realize a resolution of $864{\times}648$ 56 megapixels. A distortion of about 0.5% aberration appears in the maximum field, and a finite beam aberration of about $15{\mu}m$ is confirmed. We made a mold based on the design data and completed the prism lens through exodus molding. We confirmed the shape error (< $30{\mu}m$) and surface roughness (> 40 nm) of the three sides. We made the video-information-display prototype glasses using prism lens by measuring the performance, we determined the distortion aberration (0.3%) and SVGA resolution. Our approach will enable fabrication of a portable large-screen display device for glasses and sunglasses for the domestic market and, after 2015, for the world market.