• Journal of the Korean Society of Safety
• /
• v.31 no.1
• /
• pp.81-86
• /
• 2016

The WMSDs are known to occur more in upper extremity than lower extremity, and such a ratio is increasing each year. The motions or repeated work requiring excessive strength beyond worker's maximum grip strength were known as a major cause of the WMSDs in upper extremity. To prevent the WMSDs in upper extremity, research on the grip strength characteristics analysis of field workers that can be used as basic data for work design and manual tool design is needed. The purpose of this study is to identify various variables affecting grip strength and is to find out the impacts of grip strength on WMSDs. This research measured the grip strength of 327 field workers at Heavy Industries, and also conducted a questionnaire survey on individual characteristics and job characteristics. As a result of analyzing grip strength, the grip strength was statistically significant (P<0.1) according to the body surface area (BSA) of the research subjects. The differences between percentile groups of grip strength were statistically significant (P<0.1) according to pain levels of hand/wrist/finger and arm/elbow. The comparison results between the average grip strength of Korean adult males and the average grip strength of the survey-targeted heavy industry workers show that the average grip strength of the heavy industry workers was higher by 9.75 kg. This study analyzed relationship between grip strength and the pain levels of hand/wrist/finger and arm/elbow, and compared the findings in this study with those of existing preceding studies. Also, this research comparatively analyzed the grip strength of Korean adult males and survey-targeted heavy industry workers. The findings of this study can be used as useful data for ergonomic work design and manual tool design to prevent WMSDs at industrial worksites, given that almost no data on the grip strength of workers in the industrial sites are found in Korea.

• Journal of radiological science and technology
• /
• v.43 no.5
• /
• pp.375-382
• /
• 2020

PET/CT is a medical equipment that detects 0.511 MeV of gamma rays. The radiation workers are inevitably exposed to ionizing radiation in the process of handling the isotope. Accordingly, PET/CT workers use syringe shields made of lead and tungsten to protect their hands. However, lead and tungsten are known to generate very high scattering particles by interacting with gamma rays. Therefore, in this study, we tried to find out the effect on the scattering particles emitted from the syringe shield. In the experiment, first, the exposure dose to the hand (Rod phantom) was evaluated according to the metal material (lead, tungsten, iron, stainless steel) using Monte Carlo simulation. The exposure dose was compared according to whether or not plastic is attached. Second, the exposure dose of scattering particles was measured using a dosimeter and lead. As a result of the experiment, the shielding rate of plastics using the Monte Carlo simulation showed the largest difference in dose of about 40 % in lead, and the lowest in iron, about 15 %. As a result of the dosimeter test, when the plastic tape was wound on lead, it was found that the reduction rate was about 15 %, 28 %, and 39 % depending on the thickness. Based on the above results, it was found that 0.511 MeV of gamma ray interacts with the shielding tool to emit scattered rays and has a very large effect on radiation exposure. However, it was considered that the scattering particles could be sufficiently removed with plastics with a low atomic number. From now on, when using high-energy radiation, the shielding tool and the skin should not be in direct contact, and should be covered with a material with a low atomic number.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.1
• /
• pp.69-75
• /
• 2022

This paper proposes a method of identifying the moment when a student with developmental disabilities needs assistance intervention in performing barista vocational training using virtual reality-based realistic contents. To this end, 21 students enrolled in a vocational training center for persons with disabilities were selected as study subjects. These students were trained to recognize the barista tools in a virtual reality environment. During the training, if students experienced difficulties and were unable to proceed further, they were asked to raise their hands or verbally request assistance. Using the collected data, two hypotheses were established based on the distance between the hand of the student and each barista tool in the virtual reality space in order to derive a criterion for judging the moment when an intervention is required. As a result of verifying the hypotheses, this study found that the cumulative distance from the hand of a student, who successfully finished the training without requiring an intervention, to the target barista tool as well as adjacent tools was significantly shorter than the cumulative distance to other barista tools.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.4
• /
• pp.1216-1233
• /
• 2023

Conventional occupational therapy (OT) is conducted under the observation of an occupational therapist, and there are limitations in measuring and analyzing details such as degree of hand tremor and movement tendency, so this important information may be lost. It is therefore difficult to identify quantitative performance indicators, and the presence of observers during performance sometimes makes the subjects feel that they have to achieve good results. In this study, by using the Unity3D and artificial intelligence (AI) speaker, we propose a system that allows the subjects to steadily use it by themselves and helps the occupational therapist objectively evaluate through quantitative data. This system is based on the OT of the sensory integration approach. And the purpose of this system is to improve children's activities of daily living by providing various feedback to induce sensory integration, which allows them to develop the ability to effectively use their bodies. A dynamic OT cognitive assessment tool for children used in clinical practice was implemented in Unity3D to create an OT environment of virtual space. The Leap Motion Controller allows users to track and record hand motion data in real time. Occupational therapists can control the user's performance environment remotely by connecting Unity3D and AI speaker. The experiment with the conventional OT tool and the system we proposed was conducted. As a result, it was found that when the system was performed without an observer, users can perform spontaneously and several times feeling ease and active mind.

• Journal of Internet Computing and Services
• /
• v.15 no.3
• /
• pp.11-19
• /
• 2014

The natural user interface/experience (NUI/NUX) is used for the natural motion interface without using device or tool such as mice, keyboards, pens and markers. Up to now, typical motion recognition methods used markers to receive coordinate input values of each marker as relative data and to store each coordinate value into the database. But, to recognize accurate motion, more markers are needed and much time is taken in attaching makers and processing the data. Also, as NUI/NUX framework being developed except for the most important intuition, problems for use arise and are forced for users to learn many NUI/NUX framework usages. To compensate for this problem in this paper, we didn't use markers and implemented for anyone to handle it. Also, we designed multi-modal NUI/NUX framework controlling voice, body motion, and facial expression simultaneously, and proposed a new algorithm of mouse operation by recognizing intuitive hand gesture and mapping it on the monitor. We implement it for user to handle the "hand mouse" operation easily and intuitively.

• Journal of the Ergonomics Society of Korea
• /
• v.33 no.2
• /
• pp.109-124
• /
• 2014

Objective: This study was conducted for one-hand users including hemiplegic clients currently using general folding manual wheelchairs, so as to analyze their specific problems and recommend solutions regarding usage. Background: Traditional manual wheelchairs require considerable use and control of both hands for operation, thus adaptations become necessary for individuals with asymmetrical use of hands. Method: Thirty hemiplegic clients who were admitted to rehabilitation and convalescent hospitals participated as subjects. The research tools were general folding manual wheelchairs commonly used by people with impaired gait, and the Wheelchair Skills Tests (WST) WST-M/WCU 4.1 version was adopted as the assessment tool. All participants were asked to fill out questionnaires on demographics and wheelchair usage characteristics. Assessment procedures were performed with currently used manual wheelchairs and with/without the use of foot to control the wheelchair. Results: When the participants drove folding manual wheelchairs without the use of foot, even the lowest failure rate among the WST items tested recorded 96.7%. On the contrary, with the use of foot in maneuvering the wheelchairs, failure rates dropped noticeably and success rate among the WST items tested was as high as 86.7%. Conclusion: These findings imply that the use of one-arm (hand) propellable (drivable) wheelchair can be an active and effective solution in resolving problems for hemiplegic clients using existing manual wheelchairs. As such, the government should provide institutional support to further develop and distribute this device or technology, and promote relative research in tandem. For now, the supply of commercially available device to hemiplegic clients is deemed urgent and also a mechanism to provide the devices and relevant services. Application: This study offers viable solutions for hemiplegic clients who rely on existing manual wheelchairs to increase their mobility and occupational performance.

• Journal of Science and Technology Studies
• /
• v.12 no.1
• /
• pp.45-78
• /
• 2012

What is a disaster? And what can science and technology studies tell us about it? There might be numerous definitions about disaster. In this article, we will posit that disaster is an incident when sociotechnical system actor-network broke down against the other force in their "trial of strength". This is a process that punctualized actor-network is depunctualized, and a status that readiness-to-hand of Being recedes while pesentness-at-hand of tool-being comes forward. Using the concept of disaster as a case study, we will consider how Latourian ontology overlaps with Heideggerian philosophy of technology. This STS approach which hasn't been previously studied might provide us with new theoretical framework that enables us to construe the assemblage of technoscience and nature-society in the field of PUS or NPSS.

• International Journal of Computer Science & Network Security
• /
• v.24 no.6
• /
• pp.161-170
• /
• 2024

With the technological advances, the humans have made so much progress in the ease of living and now incorporating the use of sight, motion, sound, speech etc. for various application and software controls. In this paper, we have explored the project in which gestures plays a very significant role in the project. The topic of gesture control which has been researched a lot and is just getting evolved every day. We see the usage of computer vision in this project. The main objective that we achieved in this project is controlling the computer settings with hand gestures using computer vision. In this project we are creating a module which acts a volume controlling program in which we use hand gestures to control the computer system volume. We have included the use of OpenCV. This module is used in the implementation of hand gestures in computer controls. The module in execution uses the web camera of the computer to record the images or videos and then processes them to find the needed information and then based on the input, performs the action on the volume settings if that computer. The program has the functionality of increasing and decreasing the volume of the computer. The setup needed for the program execution is a web camera to record the input images and videos which will be given by the user. The program will perform gesture recognition with the help of OpenCV and python and its libraries and them it will recognize or identify the specified human gestures and use them to perform or carry out the changes in the device setting. The objective is to adjust the volume of a computer device without the need for physical interaction using a mouse or keyboard. OpenCV, a widely utilized tool for image processing and computer vision applications in this domain, enjoys extensive popularity. The OpenCV community consists of over 47,000 individuals, and as of a survey conducted in 2020, the estimated number of downloads exceeds 18 million.

• Journal of the Korean Society of Radiology
• /
• v.17 no.7
• /
• pp.1099-1108
• /
• 2023

The mortise view radiography procedure is an ankle joint examination and observes the presence of trauma, sprain, or dislocation suspected in the ankle joint. The auxiliary equipment used during the mortise view radiography procedure can generate artifacts in the radiograph images and is not diverse enough to be custom-made for each patient; not cost-efficient. The purpose of this study is to create a custom assistive device to support mortise view radiography procedure. This study utilized 3D printing technology to create the mortise view radiography procedure assistive device (ShinHan Device; SHD). The lengths of the tibiotalar joint (TTJ), talar calcaneal joint (TCJ), and medial joint (MJ) were measured and evaluated by five researchers using both SHD and the prototype Hologic tool. The mean ranges were found to be 39.42-39.47 mm for TTJ, 31.41-31.57 mm for TCJ, and 21.21-21.23 mm for MJ while using SHD device. On the other hand, the measurements showed mean ranges of 39.73-39.79 mm for TTJ, 31.46-31.50 mm for TCJ, and 21.31-21.35 mm for MJ while using the Hologic tool. Based on this study results, the error ranges at all positions decreased by 24% for TTJ, 17% for TCJ, and 36% for MJ when using SHD device compared to the Hologic tool. Moreover, when SHD was used, it allowed for a highly reproducible examination posture (ICC = 0.99), and it enabled the acquisition of radiograph images without artifacts, which were present in the Hologic tool.

• Journal of the Korean Society of Industry Convergence
• /
• v.5 no.3
• /
• pp.201-208
• /
• 2002

The machine tool which operates by hand is replacing by CNC machine tool to improve the quality of the product and the productivity in modem mechanic industry. The precision of machine part is influenced greatly the surface roughness by cutting condition of machine tool. So this study was performed to examine the aluminium surface roughness of section according to change of strength rating, nose radius, cutting speed, using live center. The results of this study are as follows; 1. In the case of 56mm diameter of test piece(length is below triple of diameter), whether establish the live center or not, doesn't influence to the surface roughness, and it is possible to make product without the live center. 2. The average surface roughness of 42mm diameter(length is quadruple of diameter) is similar to the 56mm diameter in the cutting condition of nose radius 0.8mm and cutting speed 140mm/min, but there are increases and differences in other cutting conditions. 3. In the case of test piece length more 70m/min(140m/mm) and nose radius improved greatly using the live center. 4. In the case of test piece length is quintuple of diameter, the nose radius must choose big tool and increase the cutting speed in preference live center establishment availability to improve that is surface roughness. Conclusively, if aluminum test piece length is fewer than triple of diameter, can process without establishing live center. If aluminum test piece length is more than quintuple of diameter, cutting conditions to improve surface roughness are (1) cutting speed (2) nose radius (3) whether the live center uses or not.