• Journal of Families and Better Life
• /
• v.25 no.3 s.87
• /
• pp.119-135
• /
• 2007

The purpose of this study is to find out the level of digital stress that people experience and to investigate the effects of socio-economic variables on that. To collect data, structured questionnaire was developed and 1,200 questionnaires were distributed through internet. There were 2 dimensions in this study to examine digital stress. First dimension was about the devices themselves: computers and the other digital goods. Second dimension was about the time digital stress occurring in consumers' decision-making process: purchasing and using. Based on Yeo&Kim(2004), sub-dimensions of purchasing and using aspects were chosen. 5 sub-dimensions in purchasing side were new technology, cost, variety of alternatives, warranty service, and informational problem 6 sub-dimensions in using field were mal(or impaired)-functioning. physical aspects, immaturity in use, pressure to use, addiction to use, and informational problem. As independent variables, sex, age, educational level, digitalization acceptability and computer usability were used. The overall level of digital stress was around the average point which was not as high as expected. Digital stress of purchasing was higher than that of using. First, in purchasing aspects, the level of digital stress was relatively high in cost, variety of alternatives and warranty service. Hence, clear communications with consumers about the distinctive aspects and cost of digital devices in market are needed. Secondly, in using side, mal-functioning and physical aspects were relatively more powerful stressors. In the other words, the more serious problems were not from the characteristics of individual consumers but from those of products. Producers should put their best efforts to reduce imperfection (defectiveness) and develop user-friendly digital devices. Also, users' individual efforts to overcome the problems that can be solved privately are necessary. Finally, it was discovered that sex and computer usability were very important variables on digital stress. To extend computer usability of consumers and get over digital illiteracy, it is essential to expand the paths to give chances for people to contact with computers and other digital goods. Still there are lots of people whore computer-illiterate or low-skilled at computers. In policies or educational programs made by government, communities, or schools, more attention should be paid to the digitally vulnerable groups.

• Journal of the Ergonomics Society of Korea
• /
• v.34 no.4
• /
• pp.313-326
• /
• 2015

Objective: The objective of this research is to quantitatively analyze muscle activities of arm and shoulder, according to direction in various types of one-handed manual material handling, based on surface electromyography. Background: Workers in industrial sites frequently carry out one-handed manual material handling using arm and shoulder muscles. Therefore, chronic load and accumulated fatigue occur to arm and shoulder muscles, which becomes a main cause of upper arm and shoulder musculoskeletal disorders. The shoulder muscles have widely range of motion, and complex interactions take place among various muscles including rotator cuff muscles. In this regard, research on interactions among should muscles, according to such various dynamic motions, is required. Method: Ten male subjects in their 20s participated in this research. This research considered upward, downward, leftward, rightward, forward and backward directions and fourteen muscles around arm and shoulder (biceps brachii and trapezius, etc.) as independent variables. The mean muscle activity was set as the dependent variable. This research extracted $4^{th}{\sim}7^{th}$ repetition signals according to ten times of repetitive muscle contraction, and analyzed the muscle activity concerned using the envelope detection technique. Results: The mean muscle activity of upward direction was analyzed highly statistically significant. The reason is that the effect of gravity works to arm and shoulder muscles. Also, it is conjectured that deformation of coracoacromial ligament was caused, and its contact pressure increased, due mainly to the shoulder flexion, and therefore load was analyzed high. Muscle activity was analyzed significantly low, according to concentric ballistic motion used in the concentric contraction phase by storing elastic energy in the eccentric contraction phase with a motion to bring the weight to the front of subject's body as to downward, leftward and backward directions. Because, elbow joint's flexion-extension motions mainly occurred, biceps brachii was analyzed high muscle activity as the prime mover. Conclusion: The information on the quantitative load of muscles can be applied to ergonomic work design for one-handed manual material handling to minimize muscle load. Application: This research has effectively identified muscle activity according to dynamic contraction by applying an envelope detection technique. The results can be used for ergonomic work design to minimize muscle load during the one-handed manual material handling, according to each direction. The research results are expected to be used for musculoskeletal disorder prevention and physiotherapy in the rehabilitation medical field, based on the muscle load of arm and shoulder in various directions.

• Information Systems Review
• /
• v.14 no.2
• /
• pp.1-19
• /
• 2012

Recently due to the enhancement of education and lifestyle, the trend of healthcare services are changed to a more active and differentiated service in which a continuous self health care is possible. The Smart-Telemedicine system offers medical services by merging Blue-tooth and telecommunication modules to former blood pressure, blood sugar, heartbeat and temperature measuring devices. Moreover, it could analyze one's health pattern which would be helpful for the patient to prevent potential future illness. In addition, the easier accesses to various remote controllable medical check-up programs are offered to public as a number of available smart phone are rapidly escalating. The Smart-Telemedicine system provides the most ideal interactive medical service via accessible smart phones and mobile medical check-up devices at anywhere and anytime. It is very beneficial since it can save patients' time and money because people can reach to the service right at their home and be allowed to take charge of their health care process via longitudinal health data. Therefore, not only social costs that occur in elderly community would be saved, but also business in various forms of medical service field transactions could be possible. This paper will suggest the Smart-Telemedicine System for preventive medicine, its design and analysis of business models and the evaluation of those model.

• Fire Science and Engineering
• /
• v.30 no.6
• /
• pp.48-56
• /
• 2016

A crude oil leakage from a large atmospheric storage tank occurred on 4 April 2014 at 14:50 in Ulsan City, while storing the crude oil in the tank. Emergency Rescue Control Group was deployed in the scene. The company, Fire Service Headquarters and associated agencies got together in Command Post (CP) for discussing an effective corresponding strategy. Many solution plans were drafted in the debate such as power down, stopping the facilities, checking the density of inflammable gas, suppressing oil evaporation, moving the leaked crude oil to a nearby tank and a processing plant and avoiding marine pollution. All the solutions were carried out in cooperation with several agencies and partners. The oil leakage accident was successfully settled up within the process of responding, The Fire Service Headquarters and the company thought that the most important thing was the suppression of oil evaporation and the elimination of ignition source. With Fire Service Headquarters and several agencies' every effort, an explosion and a fire didn't occurred in the scene. This study suggest the improvement of the operating system in Emergency Rescue Control Group in case of petroleum leakage, explosion and fire accidents of atmospheric storage tank, different from a ordinary disaster. Assuming that petroleum leakage in atmospheric storage tank develop the explosion and fire accidents, the spreading speed of the flame and the burning time was experimented and compared with each other. Furthermore, this study concentrates on the effective field response plan prepared for the afterward explosion and fire accidents from petroleum leak in a storage tank, with the database experimented and analyzed in accordance with the angle of radiation in the foam nozzle and the pressure of pumping in a fire engine.

• Fire Science and Engineering
• /
• v.33 no.3
• /
• pp.51-55
• /
• 2019

To prevent ozone depletion caused by CFCs, the replacement of Halon with clean agents has been developed in the fire protection field along with refrigerants, detergents, and foaming agents. The alternatives for Halon 1211 have been developed in the portable fire extinguisher area and HCFC-123 is used widely as a clean fire extinguishing agent. The type of expellant gas is important because their own vapor pressure is low. In this study, HCFC-123, HCFC-124, HFC-125, and Novec-1230 were selected as fire extinguishing agents and CO₂, which is expected to improve the fire extinguishing ability, was chosen as the expellant gas. For each agent, experiments changing the agent and CO₂ amount were carried out and HCFC-123 showed a good result, as expected. The extinguisher, HCFC-123 of 1.5 kg, showed the same ability to suppress a class A and B fire as the extinguisher, HCFC-123 of 2.5 kg, which is currently sold on the market. According to this result, the expellant gas has a subsidiary fire extinguish effect. This can reduce the amount of HCFC fire extinguishing agent, which is categorized in the phase-out alternatives, and is a more eco-friendly and economical fire extinguisher than the previous one. This study can also help solve the problems of CO₂ fire extinguishers for class B and C fires, and can be used to extinguish electric and electron facilities fire, which contains large amounts of class A fire combustibles.

• Journal of Adhesion and Interface
• /
• v.21 no.3
• /
• pp.101-106
• /
• 2020

In this study, epoxy-modified acrylate was synthesized. The synthesized acrylate was added to the composition for sheet molding compound (SMC) in the range of 5 phr to 15 phr. The prepared SMC prepreg was molded at high temperature and pressure to produce a glass fiber reinforced composite. Physical properties such as tensile and impact strength of the composite were measured, respectively. Experimental data show that the composite with 5 phr of synthesized acrylate has 20% improved tensile strength and 12% improved impact strength than that of the reference sample.

• Journal of Plant Biology
• /
• v.35 no.4
• /
• pp.317-322
• /
• 1992

The nitrogen fixation activity and environmental factors of Lespedeza bicli!oy Turcz, forming annual root nodules by symbiotic Rhizobium sp. were analyzed in the field conditions during the growing period. Seasunal changes of $N_2-fixation$ activity showed the maximum value of $120\;\mu\textrm{M}\;C_2_H4{\cdot}noduie\;g\;fw^{-1}{\cdot}hr^{-1}$ during the active growing period (June) and varied significantly depending on the growth phase and environmental factors. The maximum activities were attained at the conditions of pH 7, $30^{\circ}C$ of temperature, 18 Kpa of oxygen partial pressure and inhibited by water stress and nitrogen sources. The habitat soil was weak acidic and poor in nitrogen, phosphorus and organic matter contents. The leaf area ratios and chlorophyll contents were ranged from 442 to $48;\textrm{cm}^2{\cdot}g\;dw^{-1}$ and from 33 to $38\;\mu\textrm{g}\;chI{\cdot}\textrm{cm}^2$. Nitrogen contents in each organ showed the maximum of 46, 19 and $11\;mg{\cdot}g\;dw^{-1}, respectively for leaf, rool and stem in the early period. The highest phosphorus contents were 4.2, 1.2 and $0.6\;mg{\cdot}g\;dw^{-1}$, respectively for leaf. root and stem in early growing period. The allocation ratios of nitrogen quantity showed 60% for leaves and 73% for roots during the active and late growth period, and 22% [or stems in average. The allocalion ralios o[ phosphorus quantity showed 58% for leaves during the most productive period, 70% for roots in the pre-growth stage and 26% for stems in average.verage.

• Tuberculosis and Respiratory Diseases
• /
• v.41 no.2
• /
• pp.158-164
• /
• 1994

Pulmonary alveolar proteinosis is a disease of unknown etiology characterized by the accumulation of PAS positive lipoproteinaceous material in the alveolar spaces sparing septum. The therapy which has enjoyed the greatest success is whole lung lavage. The authors reported here, a case of 44 year old male patient with pulmonary alveolar proteinosis, and this is the 7th case in Korea. The patient underwent whole lung lavage but expired due to brain edema complicated by the procedure. He complained exertional dyspnea and cyanotic lips, and presented fine inspiratory crackle at both lower lung fields, decreased arterial oxygen pressure, and diffuse infiltration at whole lung field. Light microscopic finding of lung tissue obtained by transbronchial lung biopsy revealed PAS positive amorphous, granular material filled in the alveolar spaces, and electron microscopy of bronchoalveolar lavage fluid concentrate showed many electron-dense multi-lamellated structures. To treat the disease, the authors tried whole lung lavage of left lung with $37^{\circ}C$ isotonic saline under general anesthesia. However, he expired due to brain edema probably due to dilutional hyponatremia complicated by the procedure, 11 days after the procedure. Whole lung lavage is known relatively safe, but fatal complication may occur like this case.

• Korean journal of communication and information
• /
• v.48
• /
• pp.90-108
• /
• 2009

While the term of the institution as social manifestation has been discussed intensively through various theoretical approaches over the last few years in Social Sciences, such a debate has been missing so far in Communication Sciences. This paper attempts a theoretical discussion about the media as an institution in the field of Communication Sciences by applying the theory of organizational sociological neo-institutionalism. This research started out with the question which influence exerts the media on organizations and participants. The media is understood as an institution in the sense of permanent monitoring systems which create a) normative expectations b) which become stronger in order to assert such normative expectations c) the norms are applied by the participants d) in this application process, the participants accept the organizations, look primarily for the chosen paragraphs and exert an influence to change the norms. Organizations orient themselves at the institutional rules, because this way, they want to gain legitimacy and support. The media unfold their influence on organizations through certain obligations in addition to the pressure of the participants who deal with the organization and the media. Thus, media cannot exert influence independent from the organizationbut the participants accept the situation, which is generated by the many conflicting processes within the organization, they analyse them and transfer them.

• Journal of the Korean Geotechnical Society
• /
• v.27 no.3
• /
• pp.41-54
• /
• 2011

The present study analyzes the stability of waterfront quay wall under the combined action of earthquake and tsunami. Adopting the limit equilibrium method, the stability of waterfront quay wall is checked for both the sliding and overturning. Forces due to tsunami are compared with the proposed formula and the 3-D one-field Model for immiscible TWO-Phase flows (TWOPM-3D). Variations of the stability of wall are also proposed by the parametric study including tsunami water height, horizontal seismic acceleration coefficient, internal friction angle of soil, friction angle between the wall and the soil and the pore water pressure ratio. The present study about the stability of wall is also compared with the case when earthquake and tsunami are not considered. As a result, the result of numerical analysis about the tsunami force is similar to that of proposed formula. When earthquake and tsunami are simultaneously considered, the stability of wall in passive case significantly decreases and tsunami forces in active case are affected as a resistance force on the wall and so the stability of wall increases.