• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.31 no.5
• /
• pp.467-472
• /
• 2007

In this study the penetration distance of liquid phase fuel(i.e. liquid phsae length) was investigated in evaporative field. An exciplex fluorescence method was applied to the evaporative fuel spray to measure and investigate both the liquid and the vapor phase of the injected spray. For accurate investigation, images of the liquid and vapor phase regions were recorded using a 35mm still camera and CCD camera, respectively. Liquid fuel was injected from a single-hole nozzle (l/d=1.0mm/0.2mm) into a constant-volume chamber under high pressure and temperature in order to visualize the spray phenomena. Experimental results indicate that the liquid phase length decreased down to a certain constant value in accordance with increase in the ambient gas density and temperature. The constant value, about 40mm in this study the, is reached when the ambient density and temperature of the used fuel exceed critical condition.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.5
• /
• pp.111-116
• /
• 2016

According to the Ministry of Science, ICT and Future Planning's survey of information gap, smartphone retention rate of disabled people stayed in one-third of non-disabled people, the situation is significantly less access to information for people with disabilities than non-disabled people. In this paper, we develop an application, CallHelper, that helps to be more convenient to use mobile voice calls to the auditory disabled people. CallHelper runs automatically when a call comes in, translates caller's voice to text output on the mobile screen, and displays the emotion reasoning from the caller's voice to visualize emoticons. It also saves voice, translated text, and emotion data that can be played back.

• Journal of the Korean Society of Safety
• /
• v.32 no.5
• /
• pp.88-95
• /
• 2017

As the safety fields are expanding to a variety of industrial fields, safety technology has been developed by convergence between industrial safety fields such as mechanics, ergonomics, electronics, chemistry, construction, and information science. As the technology convergence is facilitating recently advanced safety technology, it is important to explore the trends of safety technology for understanding which industrial technologies have been integrated thus far. For studying the trends of technology, the patent is considered one of the useful sources that has provided the ample information of new technology. The patent has been also used to identify the patterns of technology convergence through various quantitative methods. In this respect, this study aims to identify the convergence patterns and fields of safety technology using association rule mining(ARM)-based patent co-classification(co-class) analysis. The patent co-class data is especially useful for constructing convergence network between technological fields. Through linkages between technological fields, the core and hub classes of convergence network are explored to provide insight into the fields of safety technology. As the representative method for analyzing patent co-class network, the ARM is used to find the likelihood of co-occurrence of patent classes and the ARM network is presented to visualize the convergence network of safety technology. As a result, we find three major convergence fields of safety technology: working safety, medical safety, and vehicle safety.

• Journal of Power System Engineering
• /
• v.14 no.3
• /
• pp.5-12
• /
• 2010

The purpose of this study is to analyze heterogeneous distribution of branch-like structure at downstream region of inner spray. The previous many studies about diesel spray structure have yet stayed in the analysis of 2-D structure, and there are very few of informations which are concerned with 3-D analysis of the structure. The heterogeneous distribution of droplets in inner spray affects the mixture formation of diesel spray, and also the combustion characteristics of the diesel engines. Therefore, in order to investigate 3-D structure of evaporative spray the laser beam of 2-D plane was used in this study. Liquid fuel was injected from a single-hole nozzle (l/d=5) into a constant-volume vessel under high pressure and temperature in order to visualize the spray phenomena. The incident laser beam was offset on the central axis. From the images analysis taken by offset of laser beam, we examine formation mechanism of heterogeneous distribution by vortex flow at the downstream of the diesel spray. As the experimental results, the branch-like structure formed heterogeneous distribution of the droplets consists of high concentration of vapor phase in the periphery of droplets and spray tip of branch-like structure. Also the 3-D spatial structure of the evaporative diesel spray can be verified by images obtained from 2-D measurement methods.

• Restorative Dentistry and Endodontics
• /
• v.8 no.1
• /
• pp.133-137
• /
• 1982

Radiography is one of the important tool adopted in daily dental practice and medical diagnosis. To visualize soft tissuechange various contrast media has Been introduced. Any cavity or space can be easily determined by increasing the X-ray absorption of the cavity using the radiopaque contrast media which widely employed in medical radiography to show much of the digestive, cardiovascular, pulmonary, and renal system. The essential part of any radiopaque medium is a heavy element that can absoarb most of the X-ray beam. The element must be noninjurious and easily eliminated. Both aqueous and oil suspensions of iodine containing compounds' are available to the dental profession, for example Lipiodol and Dionosil. The study was designed to determine toxic effect of Lipiodol to the vital pulp and to confirm visualization ioprovement in pulp canal. 1. Thin mixture of Calcium hydroxide and Lipiodol was applied to 19 deep vital cavities for 24 hours. Only one case complained slight pain for short time. 2. Cotton pellet over-saturated in Lipiodol was inserted in coronal chamber of which 6 were non vital and 5 were vital. The transference of Lipiodol was not noticed in every case after 24 hours. 5 cases with vital pulp tissue in the canals showed no clinical symptome. 3. Extracted 20 teeth were routinely prepared for endodontic treatment and applied Lipiodol in conjunction with cotton fiber as deep as midportion of the roots. After 24, hours the medicament reached to nearly the end of apex, but there were no evidence of penetration in dentine layer and migrate into ramified canal.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.14 no.5
• /
• pp.1234-1243
• /
• 1990

Double coaxial are jets(annular and coaxial air jets) between which propane gas is fed was selected to study the structure of diffusion flames in turbulent shear flow. Schlieren and direct photographs are taken to visualize the flame structure. Mean and fluctuating temperatures and ion currents were measured to investigate the macroscopic and the instantaneous flame structure. The objective of this study is to understand the interaction between combustion and mixing process especially in the transition region of turbulent shear flow. The investigation reported in this paper focuses on the macroscopic and the instantaneous structures of three flames obtained. The increased mixing effect resulting from increase of Reynolds number of central air jet makes the flame bluish and short. When the velocity of surrounding air stream is higher than that of central air jet, the instantaneous flame structure is composed of coherent structure. It is considered that the flame structure of transitional region of mixing layer depends on the structure of mixing layer of non-reacting conditions.

• Journal of the Ergonomics Society of Korea
• /
• v.30 no.5
• /
• pp.683-688
• /
• 2011

Objective: The aim of this study is to develop a distributed representative human model(DRHM) generation and analysis system. Background: DRHMs are used for a product with multiple-size categories such as clothing and shoes. It is not easy for a product designer to explore an optimal sizing system by applying various distributed methods because of their complexity and time demand. Method: Studies related to DRHM generation were reviewed and the RHM generation interfaces of three digital human model simulation systems(Jack$^{(R)}$, RAMSIS$^{(R)}$, and CATIA Human$^{(R)}$) were reviewed. Results: DRHM generation steps are implemented by providing sophisticated interfaces which offer various statistical techniques and visualization methods with ease. Conclusion: The DRHM system can analyze the multivariate accommodation percentage of a sizing system, provide body sizes of generated DRHMs, and visualize generated grids and DRHMs. Application: The DRHM generation and analysis system can be of great use to determine an optimal sizing system for a multiple-size product by comparing various sizing system candidates.

• Structural Engineering and Mechanics
• /
• v.12 no.5
• /
• pp.541-558
• /
• 2001

The design specifications of guard fences in Japan were reexamined and the revised specifications were implemented from April 1999. Because of the huge consumption in time and cost to test the performances of full-scale guard fences in the field, some assumptions are adopted while modifying the design specifications, and numerical analyses are necessary to confirm the impact performance and safety level of new types of steel highway guard fences. In this study, the finite element models are developed for the heavy trucks and steel highway guard fences to reenact their behaviors, and the solution approach is carried out using nonlinear dynamic analysis software of structures in three dimensions (LS-DYNA). The numerical simulation results are compared with the full-scale on-site testing results to verify the proposed analysis procedure. The collision process is simulated and it is also made possible to visualize the movement of the truck and the performances of guard fences. In addition, the energy shift of the truck kinetic energy to the truck and guard fence Internal energy, and the energy absorption of each guard fence component are studied for the development of a new design methodology of steel highway guard fences based on the energy absorption capacity.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.5
• /
• pp.1168-1173
• /
• 2013

This paper proposes a new visualization method based on cloud technique which uses internal relationship of user correlation and external relation of social network to visualize user relationship hierarchy. The visualization method of this paper can well represent user-focused relationship hierarchy on social networks by a correlation matrix. The importance of a access node reflects into user relationship hierarchy by exploiting external relation of social network. Users of the method can well understand user relationships on account of representing user relationship hierarchy from social networks. In addition, the method use hadoop and hive for distribution storing and parallel processing which the result of calculation visualizes hierarchy graph using D3.

• Journal of radiological science and technology
• /
• v.20 no.2
• /
• pp.56-62
• /
• 1997

To evaluated the image quality and the patient exposure for the chest radiography, its fundamental imaging properties were investigated. The basic imaging properties were evaluated by measuring characteristic curves, relative speeds, average gradient, and patient exposure dose. The image qualities were evaluated by using a rotating meter. It was found that the film gradient of SRO750/SRH system was 3.13 and that of SRO750/HR-C30 was 1.77. The ratio of SRO1000/TMH to FS/RP-1 was 1 to 18.2. It was possible to visualize the static image when the exposure time was less than 2.5 msec in patient that had respiratory excessive motion, heart beat and natural physical motion, and less than 8.5 msec in normal. The ratio of medical exposure dose compared with our method was 1 to 25 in the routine chest radiography and maximum was 1 to 70. In estimation of the image quality in same cases, we found that the image of SRO1000/SRH and TMH of super sensitive systems was the same results. We found that these super sensitive screen-film systems were available for the chest radiography considering the relationship between the image quality and patient exposure.