• Physical Therapy Korea
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• v.11 no.4
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• pp.7-17
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• 2004

Individuals who propel wheelchairs have a high prevalence of upper extremity injuries (i.e., carpal tunnel syndrome, elbow/shoulder tendonitis, impingement syndrome). Musculoskeletal injuries can result from overuse or incorrect use of manual wheelchairs, and can hinder rehabilitation efforts. To better understand the mechanisms of upper extremity injuries, this study investigates the motion of the wrist during wheelchair propulsion. This study also examines changes in the variables that occur with fatiguing wheelchair propulsion to determine how the time parameters of wheelchair propulsion and the state of fatigue influence the risk of injury. A two dimensional (2-D) analysis of wrist movement during the wheelchair stroke was performed. Twenty subjects propelled a wheelchair handrim on a motor-driven treadmill at two different velocities (50, 70 m/min). The results of this study were as follows; The difference in time parameters of wheelchair propulsion (cadence, cycle time, push time, recovery time, and PSP ratio) at two different velocities was statistically significant. The wrist kinematic characteristics had statistically significant differences at two different velocities, but wrist radial deviation and elbow flexion/extension had no statistically significant differences. There were statistically significant differences in relation to fatigue in the time parameter of wheelchair propulsion (70 m/min) between initial 1 minute and final 1 minute. The wrist kinematic characteristics between the initial 1 minute and final 1 minute in relation to fatigue had statistically significant differences but the wrist flexion-extension (50 m/min) had no statistically significant differences. According to the results, the risk of musculoskeletal injuries is increased by fatigue from wheelchair propulsion. To prevent musculoskeletal injuries, wheelchair users should train in a muscle endurance program and consider wearing a splinting/grove. Moreover, wheelchair users need education on propulsion posture, suitable joint position, and proper recovery patterns of propulsion.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.141-148
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• 2009

An inappropriate evaluation of capacity leads to the incorrect and impractical result due to the transfer of error to the analysis and the evaluation on highway system. The traffic accident which reduces the capacity of road temporarily generates unpredictable congestion, causing difficulties in congestion management. Therefore, this research aims on the measurement of the capacity of the road in accordance to the speed at the accident which is a basic factor when performing analysis. Based on the given approach, the behavior of a vehicle in highway is understood to develop model of critical gap and model of maximum flow rate with respect to the speed of traffic flow. With the established model, the reduction rate of the capacity in highway system at the accident is measured. The result shows that the capacity is reduced by 37% when the speed of the traffic flow is 40km/h. Although the developed model can't be verified clearly, this research has shown that the reduction rate of the capacity in road system has a close relation to the speed.

• Journal of the Korean Society of Safety
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• v.29 no.2
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• pp.53-61
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• 2014

This study evaluated wind loads considering a local basic wind velocity and construction periods to define the level of applied wind loads for system supports. Structural responses of system supports were examined and compared to those of system supports with the level of wind loads following various standards and specifications for permanent and temporary structures. And, the maximum combined stress ratios were estimated to evaluate the structural safety of a considered system support. From results, it was found that the wind load level should be applied in accordance with construction periods when estimating the safety of system supports. Looking into the response by change of the basic wind velocity according to local regions, it is no need to consider wind loads in regions with the basic wind velocity of 30 m/s. However, it was analyzed that wind loads should be considered in the regions with the basic wind velocity of 40 m/s or above. In addition, wind loads should be considered in designing system supports located at the region with the basic wind velocity of 35 m/s starting from construction period of 1.5 years. The standard specification for temporary work was analyzed as an incorrect standard in evaluating wind loads, since it underestimated the response of system supports in accordance with the local basic wind velocity and construction periods.

• Journal of the Korea Institute of Building Construction
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• v.16 no.5
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• pp.463-470
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• 2016

Construction companies calculate their revenues and costs from constructing activities using the 'Percentage of Completion Method', which is based on ratio of actual construction cost to total costs estimated. The reliability of the net profit of construction companies is being evaluated lower than other industries due to incorrect application of 'Percentage of Completion Method' to cover losses actually occurred. Therefore, the purpose of this study is to verify the quality of earnings calculated based on 'Percentage of Completion Method' in terms of information usefulness. Results from empirical analysis show that investors in stock market underestimate the value of the construction companies' earning information by applying 'Percentage of Completion Method' and not actively use in investment decision making. Accordingly, it has been confirmed that the association between income information and stock prices falling. These results suggest the need for strict supervision of the supervisory authorities and the practical application of 'Percentage of Completion Method' in reliability.

• Korean Journal of Community Nutrition
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• v.20 no.2
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• pp.141-150
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• 2015

Objectives: Self perceived body image among women is drawing a lot of attention in Korea due to their unhealthy weight control behaviors. To determine the relationship between self-perceived body image and dietary behaviors among Korean women, the discrepancy between actual body size and body image perception, weight control behaviors were assessed based on age groups using the 2010 KNHANES data. Methods: A total of 1,747 subjects were selected after eliminating those of likely changing their diet recently using the 2010 KNHANES data. The subjects were divided into 3 groups, self-underweight, self-normal, and self-obese according to their perception of body image. The BMI and weight control behaviors were assessed based on age groups according to the body image perception. Results: The younger, the higher ratio of underweight, women perceived their body size as normal or overweight. Exercise and reduced food intakes were dominant among various weight control methods but unhealthy methods were dominant among self perceived overweight group. Conclusions: Incorrect body image perception and unhealthy weight control behaviors can cause nutritional problems. Nutritional education should emphasize the importance of healthy weight and proper body image perception for Korean women.

• Journal of the Korea Society of Computer and Information
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• v.24 no.2
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• pp.139-147
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• 2019

A false alarm, which is an incorrect report of an emergency, could trigger an unnecessary action. The predictive maintenance framework developed in our previous work has a feature whereby a machine alarm is triggered based on sensor data evaluation. The sensor data evaluator performs three essential evaluation steps. First, it evaluates each sensor data value based on its threshold (lower and upper bound) and labels the data value as "alarm" when the threshold is exceeded. Second, it calculates the duration of the occurrence of the alarm. Finally, in the third step, a domain expert is required to assess the results from the previous two steps and to determine, thereby, whether the alarm is true or false. There are drawbacks of the current evaluation method. It suffers from a high false-alarm ratio, and moreover, given the vast amount of sensor data to be assessed by the domain expert, the process of evaluation is prolonged and inefficient. In this paper, we propose a method for automatic false-alarm labeling that mimics how the domain expert determines false alarms. The domain expert determines false alarms by evaluating two critical factors, specifically the duration of alarm occurrence and identification of anomalies before or while the alarm occurs. In our proposed method, Hierarchical Temporal Memory (HTM) is utilized to detect anomalies. It is an unsupervised approach that is suitable to our main data characteristic, which is the lack of an example of the normal form of sensor data. The result shows that the technique is effective for automatic labeling of false alarms in sensor data.

• Earthquakes and Structures
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• v.23 no.5
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• pp.403-417
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• 2022

Reinforced concrete (RC) structures with low-strength RC columns are rampant in several countries, especially those constructed during the early 1960s and 1970s. The weakness of these structures due to overloading or some natural disasters such as earthquakes and building age effects are some of the main reasons to collapse, particularly with the scarcity of data on the impact of aspect ratio and corner radius on the confinement effectiveness. Hence, it is crucial to investigate if these columns (with different aspect ratios) can be made safe by strengthening them with carbon fiber-reinforced polymers (CFRP) sheets. Therefore, experimental and numerical studies of CFRP-strengthened low-strength reinforced concrete short rectangular, square, and circular columns were studied. In this investigation, a total of 6 columns divided into three sets were evaluated. The first set had two circular cross-sectional columns, the second set had two square cross-section columns, and the third set has two rectangular cross-section columns. Furthermore, FEM validation has been conducted for some of the experimental results obtained from the literature. The experimental results revealed that the confinement equations for RC columns as per both CSA and ACI codes could give incorrect results for low-strength concrete. The control specimen (unstrengthened ones) displayed that both ACI and CSA equations overestimate the ultimate strength of low-strength RC columns by order of extent. For strengthened columns with CFRP, the code equations of CSA and ACI code overestimate the maximum strength by around 6 to 13% and 23 to 29%, respectively, depending on the cross-section of the column (i.e., square, rectangular, or circular). Results of finite element models (FEMs) showed that increasing the layer number of new commonly CFRP type (B) from one to 3 for circular columns can increase the column's ultimate loads by around eight times compared to unjacketed columns. However, in the case of strengthened square and rectangular columns with CFRP, the increase of the ultimate loads of columns can reach up to six times and two times, respectively.

• Journal of Korean Academy of Nursing
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• v.26 no.1
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• pp.73-93
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• 1996

This study aimed to analyse the test contents of the national examination for the registered nurses (NERN) over 3 years from 1991 to 1993 in Korea. In recent years in Korea, the MCQ(multiple choice question) has been showing to be a highly recognized method for assessing the qualification of registered nurses. Unfortunately, nursing faculties have found NERN had some bad MCQs through having evaluation workshop for Some MCQs often provide so many unwriting clues which become a bias of the results, and some items fell into the category of the lower level of educational taxonomy such as isolated recall a fact or data. Frequently the stems of the questions are ambigous, unclear, disputable, esoterical or trivial. Considering those fallacies of the national examination, it is very critical to review the test items to see whether it is of high quality, is more fair, reliable and objective in depth. Therefore, this study was done to provide data for the improvement of the test contents as well as the teachers's assessment skill. For this study, the ad hoc committee was composed of 16 members, including 5 education board members of Korean Academic Nurses Association and 11 nursing faculty members. This committee had one day panel discussion and filled the checklist for this study. The process of analysing data was held over 10 times during 1992-1994. The analysis focussed on educational taxonomy such as cognitive domain(knowledge), psychmotor domain (skill), affective domain(attitude) and the level of learning such as recall, understanding, problems solving, and learning area of theory and practice, and the learning content categorised by nursing process and disease process. The test analysed using difficulty index and the structure of the test items was analysed. The conclusions and suggestion as follows : 1. In learning area, the average ratio of the theory and practice was 1 : 1.1 which was less than 1 : 2 suggested by Korean National Health Institute, and the ratio was different by the 8 leaning subjects of nursing. 2. In category of the educational taxonomy, the knowledge domain was emphasized mostly（79. 7％）, the skill domain was 14.9％, and the attitude domain was 5.4％ only. 3. In the level of learning, generally, the test items of the level of recall（45.5％） and the understanding（46.3％） were covered almost and the problem solving was 8.1％. 4. In the learning contents, generally, the test items related to nursing process was 67.2％ and that of disease process was 32.8％. However, this proportion was different by the 8 leaning subjects. Even though the nursing diagnosis has been emphasized in nursing curricula recently, the test items of this was identified very few. 5. In the structure of the test item, some were not clear, incorrect grammar, unclear description and some have clues to answer. 6. In the item analysis, the non-acceptable level of the difficulty index (means too easy) was 65.7％, and the acceptable level was 33.9％. Considering the results we would like to suggest the followings, 1. Since the test items of knowledge domain was dominant, the test items of the practice domain and attitude domain should be emphasized more. 2. The regular review and analysis of NERN should be arranged in order to improve the quality of the test items which will give influence to the nursing education positively.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.43 no.1 s.307
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• pp.53-66
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• 2006

This paper proposes the combined image retrieval system that gives the same relevance as exhaustive search method while its performance can be considerably improved. This system is combined with two different retrieval methods and each gives the same results that full exhaustive search method does. Both of them are two-stage method. One uses condensation of feature vectors, and the other uses binary-tree clustering. These two methods extract the candidate images that always include correct answers at the first stage, and then filter out the incorrect images at the second stage. Inasmuch as these methods use equal algorithm, they can get the same result as full exhaustive search. The first method condenses the dimension of feature vectors, and it uses these condensed feature vectors to compute similarity of query and images in database. It can be found that there is an optimal condensation ratio which minimizes the overall retrieval time. The optimal ratio is applied to first stage of this method. Binary-tree clustering method, searching with recursive 2-means clustering, classifies each cluster dynamically with the same radius. For preserving relevance, its range of query has to be compensated at first stage. After candidate clusters were selected, final results are retrieved by computing similarities again at second stage. The proposed method is combined with above two methods. Because they are not dependent on each other, combined retrieval system can make a remarkable progress in performance.

• Journal of the Korean Data and Information Science Society
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• v.22 no.6
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• pp.1153-1166
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• 2011

Detecting misbehavior in vehicular ad-hoc networks is very important problem with wide range of implications including safety related and congestion avoidance applications. Most misbehavior detection schemes are concerned with detection of malicious nodes. In most situations, vehicles would send wrong information because of selfish reasons of their owners. Because of rational behavior, it is more important to detect false information than to identify misbehaving nodes. In this paper, we propose the variable precision rough sets based misbehavior detection scheme which detects false alert message and misbehaving nodes by observing their action after sending out the alert messages. In the proposed scheme, the alert information system, alert profile is constructed from valid actions of moving nodes in vehicular ad-hoc networks. Once a moving vehicle receives an alert message from another vehicle, it finds out the alert type from the alert message. When the vehicle later receives a beacon from alert raised vehicle after an elapse of time, then it computes the relative classification error by using variable precision rough sets from the alert information system. If the relative classification error is lager than the maximum allowable relative classification error of the alert type, the vehicle decides the message as false alert message. Th performance of the proposed scheme is evaluated as two metrics: correct ratio and incorrect ratio through a simulation.