• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1258-1265
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• 2013

The objective of this study is to investigate the association between touchpad &buttons locations in a laptop computer and EMG amplitude and median frequency in muscles related with wrist and shoulder. Based on previous studies it was shown how abductions in wrist and shoulder could cause musculoskeletal disorders in those body parts, on which research hypotheses were established. Touchpad &buttons positions consisted of bottom center(BC), bottom center with $45^{\circ}$ rotation counterclockwise(BCR), and bottom right(BR). 10 subjects performed the task that required only touchpad &buttons usage with their preferred hand and EMG amplitude and median frequency data were recorded during 5min and analyzed afterwards. Upper trapezius and flexor carpi ulnaris were selected as target muscles. The results showed that in flexor carpi ulnaris BC resulted in greater amplitude and less median frequency than BCR and BR, but there was no significant difference between BCR and BR. In upper trapezius BC and BCR induced higher amplitude and lower median frequency than BR, but the significant difference between BC and BCR was not observed. Those phenomena occurred since BC gave rise to both wrist and shoulder abduction, BCR caused only shoulder one, and BR did not lead to abductions in both wrist and shoulder.

• Journal of Soil and Groundwater Environment
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• v.16 no.1
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• pp.32-41
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• 2011

By using a newly developed Korean risk-based corrective action (K-RBCA) software (K-RBCA) and the RBCA Tool Kit, risk assessment was performed on a site that was contaminated with aromatic hydrocarbons and heavy metals. Eight chemicals including benzene, ethylbenzene, xylenes, naphthalene, benz(a) anthracene, benzo(b) fluoranthene, benzo(a) pyrene, and arsenic that exceeded the US EPA Soil Screening Level were chosen as the target pollutants. A conceptual site model was constructed based on the site-specific effective exposure pathways. According to the RBCA Tool Kit the carcinogenic risk of arsenic was larger than $10^{-6}$, which is the generally acceptable carcinogenic risk level. The K-RBCA estimated the same level of carcinogenic risk for arsenic. With the RBCA Tool Kit, the carcinogenic risk of benzo(a) pyrene was estimated to be about $1.3{\times}10^{-6}$. However, with the K-RBCA benzo(a) pyrene did not exhibit any risk. The inconsistency between the softwares was attributed to the different fundamental settings (i.e., medium division) between the two softwares. While the K-RBCA divides medium into surface soil, subsurface soil, and groundwater, the RBCA Tool Kit divides medium into only soil and groundwater. These differences lead to the different exposure pathways used by the two softwares. The K-RBCA considers the exposure pathways in surface soil and subsurface soil separately to estimate risk, however, the RBCA Tool Kit considers the surface soil and subsurface soil as one and uses the integrated exposure pathways to estimate risk. Thus the resulting risk is higher when the RBCA Tool Kit is used than when the K-RBCA is used. The results from this study show that there is no significant difference in the risks estimated by the two softwares, thus, it is reasonable to use the K-RBCA we developed in risk assessment of soil and groundwater. In addition, the present study demonstrates that the assessor should be familiar with the characteristics of a contaminated site and the assumptions used by a risk assessment software when carrying out risk assessment.

• Tunnel and Underground Space
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• v.20 no.2
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• pp.105-111
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• 2010

This study is to consider applicability of spiral bolt strain gauge as an instrument measuring behavior of soft ground foundation and rock slope. When the instrument was installed on the ground, it can be useful to identify the state of ground behavior because it has the characteristics of flexibility, as well as to apply the ground reinforcement because it has higher pull-out resistance to the ground. From the measurement of behavior to soft ground foundation, the strain shows a stable state in the beginning, then was observed significant change in the upper and the middle of spiral bolt strain gauge after 400 days. This is analyzed that ground loosening, which is due to occurred frequent earthquake of magnitude 1~2 with increased rainfall, lead to the instability of the ground. From the measurement of behavior to rock slope, the strain shows a stable state with very little change in a period of 0~50 days and the biggest strain at 4.2 m (P6) in a period of 50~100 days, then other places except P6 was maintained at a stable state in a period of 100~160 days. The reason is analyzed because that blasting for excavated limestone surrounding was affected to the largest at P6. However, based on the size of strain change by behavior of the soft ground foundation and rock slope, it is considered that the present condition are not effected on stability of retaining structure and rock slope. In conclusion, the proposed spiral bolt strain gauge can be useful to measure behavior of soft ground foundation and rock slope, and also to be measured behavior as well as reinforcement of the target ground.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.3
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• pp.257-264
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• 2012

Objectives: This study's aims were to evaluate the effects of load center of gravity within an object lifted and feet placements on peak EMG amplitude acting on bilateral low back muscle groups, and to suggest adequate foot strategies with an aim to reducing low back pain incidence while lifting asymmetric load. Methods: The hypotheses that asymmetric load imposes more peak EMG amplitude on low back muscles contralateral to load center of gravity than symmetric load and maximum peak EMG amplitude out of bilateral ones can be relieved by locating one foot close to load center of gravity in front of the other were established based on biomechanics including safety margin model and previous researches. 11 male subjects were required to lift symmetrically a 15.8kg object during 2sec according to each conditions; symmetric load-parallel feet (SP), asymmetric load-parallel feet (AP), asymmetric load-one foot contralateral to load center of gravity in front of the other (AL), and asymmetric load-one foot ipsilateral to load center of gravity in front of the other (AR). Bilateral longissimus, iliocostalis, and multifidus on right and left low back area were selected as target muscles, and asymmetric load had load center of gravity 10cm deviated to the right from the center in the frontal plane. Results: Greater peak EMG amplitude in left muscle group than in right one was observed due to the effect of load center of gravity, and mean peak EMG amplitudes on both sides was not affected by load center of gravity because of EMG balancing effect. However, the difference of peak EMG amplitudes between both sides was significantly affected by it. Maximum peak EMG amplitude out of both sides and the difference of peak EMG amplitude between both sides could be reduced with keeping one foot ipsilateral to load center of gravity in front of the other while lifting asymmetric load. Conclusions: It was likely that asymmetric load lead to the elevated incidence of low back pain in comparison with symmetric load based on maximum peak EMG amplitude occurrence and greater imbalanced peak EMG amplitude between both sides. Changing feet positions according to the location of load center of gravity was suggested as one intervention able to reduce the low back pain incidence.

• International Journal of Advanced Culture Technology
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• v.9 no.4
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• pp.18-28
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• 2021

This study surveyed how retirees' evaluation of starting food service business affects the effectiveness their new business and quality of life, based on personal factors such as entrepreneurship and business-starting capability and environmental factors by using questionnaires. Bootstrapping was carried out in order to find out factors affecting rapidly changing new business environments and retirees' initial intent to start a business so as to verify basic hypothesis about relation between retirees' evaluation of starting food service business (social, economic, and psychological effects) and the effectiveness of their new business and quality of life and confirm whether the effectiveness of the new business acts as a medium between the evaluation of starting food service business and quality of life. In addition, PLS-MGA was performed in order to verify whether the correlations among test factors can be varied according to the kind of job the target retirees had. Having examined the basic thesis, it was found that social and economic factors had significant positive effect on the effectiveness of the new business, and social and psychological factors had significant positive effect on the quality of life. Having analyzed whether the effectiveness of new business acted as a media between evaluation of starting food service business and quality of life, there was no significant effect as a medium. Having studied whether the kind of job of the retirees controlled or affected the relations among evaluation of starting food service business, effectiveness of new business and quality of life, the results were as follows: in the office job retiree group, the greater economic factor led to increase of effectiveness of new business, while social and psychological factors influenced the quality of life; In the physical labor group, the higher social factor resulted in higher effectiveness of new business, which showed significant positive effect on the quality of life. Having researched about which element is considered to be most important in starting food service business, the most important element was found to be dish/menu, followed by staff management, accounting management, business management, and service education. Having analyzed relation between accomplishment and important consideration for starting food service business, "managers with entrepreneurship," "appropriate distribution of time to prepare for starting business," and "operation of practical field education programs" showed higher importance compared to the degree of satisfaction, so it is needed to more concentrate on the above matters. This study intends to raise retirees' awareness of starting business and help them live better life based on the analysis results, and further suggest detailed mechanism and specific operations of factors affecting retirees' decision making on starting business, such that they can use the information as basic materials to make better choices that can lead to successful business.

• The Korean Journal of Archival Studies
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• no.21
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• pp.85-116
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• 2009

Records are the social memory storage including collective memory about region, it is impossible to put into and represent all aspects of society with only public records. Japan showed the possibilities of cooperative collecting and the positive records producing and collecting efforts between organizations, even if it was not accomplished by systemic documentation strategy. Some characteristics were found out when this case was reviewed, it is as follows. To begin with, it is the cooperation and share in collecting. Especially, the activities of private organizations look better than public organizations and the cooperative collecting efforts lead to transmit much more social memory and historical records to next generation. Secondly, it is the positive records producing and collecting. The private organizations also left many records of various activities of those one accord. They recognized that recording experience and leaving behind is the survivors' responsibility. We cannot help recognizing the growth of a sense of duty and historical consciousness to record their own experience with undergoing big disaster, earthquake. Thirdly, there was no limit when it comes to the collecting scope. All records related with people and place in disaster area were the target for collecting just like slogan, 'Let's transmit records to next generation as much as possible', 'Common records and resources deserve leaving, because it is important life's information proving situations of the time. We were able to confirm the high will and enthusiasm about 'how, what and why do we transmit something of society to next generation' in this case.

• Management & Information Systems Review
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• v.38 no.2
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• pp.209-223
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• 2019

The purpose of this study was to stimulate the online word-of-mouth advertising by developing the concept of word-of-mouth constraint factors and measurement tools in connection with the SNS advertising on social networks. To achieve the objective of this study, this study was conducted in 3 phases. First, the exploratory investigation(target group interview, in-depth interview, and expert interview) was performed to determine the concept and scope of the word-of-mouth constraint based on literature study and qualitative investigation method. Second, the reliability and validity of the measurement questions were verified through the survey in order to refine the developed measurement items. Third, the predictive validity of measurement items was verified by examining the relationship with other major construct concept for which the developed measurement items were different. Based on the results of study, 6 components and a total of 23 measurement questions for those components were derived. Each was called intrapersonal and interpersonal constraint(psychological sensitivity, compensatory sensitivity, and other person assessment), structural constraint(reliability, informativity, and entertainment). We developed the measurement questions related to word-of-mouth constraint based on qualitative study and quantitative study and holistically examined the social and psychological, environmental interruption factors acting as the word-of-mouth constraint factors for SNS advertising in terms of SNS achievements and evaluation from the perspective of word-of-mouth constraint. The results will lead to creation of basic framework for systematic and empirical research on the online word-of-mouth constraint and to achievement of effective SNS word-of-mouth advertising.

• The Journal of the Korea Contents Association
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• v.19 no.5
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• pp.82-93
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• 2019

Fashion cannot encourage co-consumption with other people as a personal item, but it can lead to new consumer needs if fashion sharing service can professionally replace the time and cost of purchasing and managing goods. The purpose of this study is to empirically investigate the factors influencing the acceptance of fashion-sharing services based on the integration theory of user acceptance and utilization (UTAUT), and to discuss the virtuous cycle and sustainability pursuit of resources through the activation of the sharing. In this study, the research model for the acceptance of fashion sharing applications is schematized, and the survey was conducted 300 women aged 20~49 years. The screens of 'Project Anne', a representative fashion sharing service in Korea, were provided as a visual data. Reliability analysis, correlation analysis, confirmatory factor analysis, structural equation analysis, and multiple group analysis were performed using SPSS 23.0 and AMOS 22.0 statistical package for statistical analysis. As a result, efficiency and social influence positively influenced behavioral intention to use, and age has found that efficiency and social influences modulate the intensity of behavioral intention to use. Therefore, for the consumer acceptance and activation of fashion sharing services, marketing activities emphasizing efficiency and strengthening social influence factors are essential. Also, it is necessary to maintain the existing target group, 30~40s, and also construct additional products and price services for the 20s. This study is of academic significance in presenting basic data for empirical research on consumer acceptance of fashion sharing, and suggests a study on the influence relationship among user experience components for real users in the future.

• The Journal of the Korea Contents Association
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• v.22 no.3
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• pp.71-80
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• 2022

In the past, fish diseases were bacterial in aqua farms, but in recent years, the frequency of fish diseases has increased as they have become viral and mixed. Viral diseases in an enclosed space called a aqua farm have a high spread rate, so it is very likely to lead to mass death. Fast identification of fish diseases is important to prevent group death. However, diagnosis of fish diseases requires a high level of expertise and it is difficult to visually check the condition of fish every time. In order to prevent the spread of the disease, an automatic identification system of diseases or fish is needed. In this paper, in order to improve the performance of the disease identification system of Paralichthys olivaceus based on deep learning, the existing pre-processing method is compared and tested. Target diseases were selected from three most frequent diseases such as Scutica, Vibrio, and Lymphocystis in Paralichthys olivaceus. The RGB, HLS, HSV, LAB, LUV, XYZ, and YCRCV were used as image pre-processing methods. As a result of the experiment, HLS was able to get the best results than using general RGB. It is expected that the fish disease identification system can be advanced by improving the recognition rate of diseases in a simple way.

• Korean Journal of Materials Research
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• v.32 no.1
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• pp.9-13
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• 2022

Bullets flying with a light from the back are called "tracers". Tracers are ignited by the combustion gas of the propellant and emit bright light that allows the shooter to visually trace the flight path. Therefore, tracers mark the firing point for allies to assist shooters to hit target quickly and accurately. Conventional tracers are constructed with a mixture of an oxidizing agent, raw metal, and organic fuel. Upon ignition, the inside of the gun can be easily contaminated by the by-products, which can lead to firearm failure during long-term shooting. Moreover, there is a fire risk such as forest fires due to residual flames at impact site. Therefore, it is necessary to develop non-combustion type luminous material; however, this material must still use the heat generated from the propellant, so-called "thermoluminescence (TL)". This study aims to compare the TL emission of Dy³⁺, La³⁺ and Ho³⁺ doped MgB₄O₇ phosphors prepared by solid state reaction. The crystal structures of samples were determined by X-ray diffraction and matched with the standard pattern of MgB₄O₇. Luminescence of various doses (200 ~ 15,000 Gy) of gamma irradiated Dy³⁺, La³⁺ and Ho³⁺ (at different concentrations of 5, 10, 15 and 20 %) doped MgB₄O₇ were recorded using a luminance/color meter. The intensity of TL yellowish (CIE x = 0.401 ~ 0.486, y = 0.410 ~ 0.488) emission became stronger as the temperature increased and the total gamma-ray dose increased.