• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.2
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• pp.87-95
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• 1983

Trihalomethane removal efficiency by a fixed bed carbon adsorber was a subject of this study. Along with laboratory scale column operations, a simple adsorption model was developed to predict removal efficiency. The adsorption model includes an overall mass transfer coefficient, K and Freundlich adsorption constants, $K_F$ and n. Simulation results showed that increasing K and $K_F$ or decreasing n would take more loading and prolong run time of the adsorption bed. Typical S-shaped breakthrough curves were obtained from the experiments. The operational results at $20^{\circ}C$ and $25^{\circ}C$ indicated that a moderate difference in water temperature would not affect the treatment efficiency significantly. The adsorption constants determined from the column operation and the model simulation were reasonably close to those obtained from the isotherm test. It may be concluded that trihalomethane can be removed successfully by a fixed bed carbon adsorber.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.521-528
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• 2016

The tollbooths of a main motorway toll plaza are usually operated proactively responding to the variations of traffic demands of two-type vehicles, i.e. cars and the other (heavy) vehicles, respectively. In this vein, it is one of key elements to forecast accurate traffic volumes for the two vehicle types in advanced tollgate operation. Unfortunately, it is not easy for existing univariate short-term prediction techniques to simultaneously generate the two-vehicle-type traffic demands in literature. These practical and academic backgrounds make it one of attractive research topics in Intelligent Transportation System (ITS) forecasting area to forecast the future traffic volumes of the two-type vehicles at an acceptable level of accuracy. In order to address the shortcomings of univariate short-term prediction techniques, a Multiple In-and-Out (MIO) forecasting model to simultaneously generate the two-type traffic volumes is introduced in this article. The MIO model based on a non-parametric approach is devised under the on-line access conditions of large-scale historical data. In a feasible test with actual data, the proposed model outperformed Kalman filtering, one of a widely-used univariate models, in terms of prediction accuracy in spite of multivariate prediction scheme.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.551-564
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• 2016

Earthworks are the fundamental steps in a construction job, and are mainly comprised of smaller tasks performed by construction machinery. The productivity of the construction job can be improved by optimizing excavation, filling, and other such operations. Earthworks involve a lot of mechanical work performed by the collaboration between various kinds of construction equipment, which in turn leads to higher fuel consumption. Actual earthworks depend mostly on the intuition and experience of the driver of the machines, thus leading to inefficiency and environmental problems caused by unnecessary emission of carbon, Recently automated and information-oriented technologies are consistently being researched towards the improvement of efficiency of earthworks in the construction industry. The present research involves the introduction and understanding of the decision-making elements of heuristics which can be applied to the earthwork planning. A method is also suggested for creating an effective work path for construction machine to perform task packages (TP) for cutting and filling processes. A simulation test is performed to verify the effectiveness of suggested methods in terms of space interference and total moving distance of construction equipment.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.7
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• pp.754-759
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• 2015

Nowadays, short distance communication systems with low power energy (LPE) are developed for identification and monitoring of site identification of vessel crews and passengers (SIVCP). LPE communication modules, such as Bluetooth low energy (BLE) and Zigbee, are used for short distance communications with LPE. These modules enable 1:N communications and their popularity is growing since the modules can be mounted on movable objects, such as mobile devices and human body. When these modules are used, the important factor that affects their operation time and design are the capacity and size of battery. Therefore, they must be made as small as possible, and the battery should be selected to be slightly smaller than the module. In this study, we calculate the theoretical life of batteries used in SIVCP BLE modules using data sheet and discharge characteristic graph under the condition of a 1/250 transmission-ratio (TR). We thus calculate experimental life by measuring transmission current for the same TR, and low speed mode current for a 1/5000 TR and measure long-term experimental life using 1/25 TR for days. Through these experiments, we verify experimental methods for the prediction and extension of battery life that would enable us to select appropriate sizes of batteries based on vessel usage and passenger types. The selections of the module TR and battery size are important factors affecting the cost reduction of module design, the battery maintenance, and passenger convenience.

• Women's Health Nursing
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• v.1 no.1
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• pp.138-152
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• 1995

The condition of nutrition during infancy will greatly affect infants' physical, emotional growth, especially breast feeding is important in their growth and development, and emotional stability, too. Despite such advantages of breast-feeding, its rate has continued to fall year after year in Korea : the 95% rate in 1960's has fallen to 25.4% in 1990. It is known that such a downfall of breast-feeding rate is associated with various factors. The purpose of the study is to examine mother's and nurses' in nursery perception of the impediment factors of breast-feeding : to compare those between of breast-feeding : to compare those between two groups : to provide fundamental data for developing strategies for increasing breast-feeding. The subjects were 45 new mothers from one hospital and the same number of nurses sampled from 3 university hospitals, in Seoul. The data were collected for 11 days from April 12 to April 23, 1994 and a questionnaire was developed based on the interview with 14 nurses and 10 mothers and the literature reviews. Liker's Five-Point Scale was used as measurement. The Data were analyzed using SPSS / PC and descriptive statistics, t-test, ANOVA. The results of study are as follows : 1) Most new mothers get the information about breast-feeding from their mothers, books or newspaper, and relatives in rank than professionals(nurses or doctors). 2) The impediment factors the breast-feeding are categorized as mothers, hospital system, medical personnels and social factors. The most frequently mentioned impediment factors from mothers are 'Difficulty by operational wounds'(3.13), 'Lack of will for breast-feeding'(3.47), 'Insufficient rest and sleep'(3.52) and 'Opposition from husband or his family members'(4.77)in rank. On the other hand those factors from nurses are 'Inadequate nipple condition'(2.37), 'Decreasing milk secretion given medicine after operation'(2.63), 'Mothers knowledge deficit by poorly prepared education'(2.79) and 'Mothers abhorance of breast-feeing'(3.87) in rank. 3) As for the hospital system, the highly perceived impediment factors by mothers are 'Seperation of baby from mother after birth'(2.78), 'Lack of space for breast-feeding in the hospital'(2.93), 'Lack of facility for informing the time for breast-feeding'(3.18) and 'Because of babys' preference artificial nipple by being accustomed to it in hospital(3.97), in rank. Meanwhile, those from nurses are "Seperation of baby from mother after birth",(1.92), "Inconsistency between hospital's nursing time and mother's breast secretion time" scretion time(2.97), "Lack of space for breast-feeding in the hospital"(3.39), and "Lack of facility for informing the time for breast-feeding"(3.74) 4) As for the medical personnels, the highestly perceived Impediment factor from mothers in "Lack of professional nurses for breast-feeding"(2.96), and the lowestly perceived one is "Doctors' reluctance"(4.75). Nurses perceived same as mothers, too. 5) As for the social factors, the highestly perceived impediment factor by mothers and nurses is "Inconvience of social activities"(2.83) and the lowestly ones are "The sense of self-sacrifice"(4.22) by mothers, and "The sense of old fashioned"(4.13) by nurses. 6) The difference of the perception of impediment factors between mothers and nurses is statistically significant only in mother factor.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.354-365
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• 2016

The purpose of the study was to identify and compare levels of recognition of empowerment, job satisfaction, organizational commitment between Advanced Practice Nurses(APN) and Registered Nurses(RN) of hospitals. Data collection was done by the 85 APN and 120 RN of six large hospitals, four medium sized hospitals in Seoul and Incheon. T-test and ANOVA using SPSS 18.0 were performed. There were no significant differences of empowerment between APN($3.56{\pm}0.53$) and RN($3.50{\pm}0.54$)(t =-. 861, p = 0.390). job satisfaction between APN($3.36{\pm}0.53$) and RN($3.25{\pm}0.46$)(t =- 1.575, p = 0.117), organizational commitment between APN($3.11{\pm}0.34$) and RN($3.05{\pm}0.36$)(t =- 1.301, p = 0.195). Empowerment, job satisfaction, organizational commitment of APN and RN showed no significant differences. There are some reasons why it resulted in no significant difference between APN and RN. APN's role in Korea is not clearly established and distinguished from RN, lack of appropriacy of employment and reward, and lack of the institutional foundation for APN's operation and efficiency.

• Knowledge Management Research
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• v.21 no.3
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• pp.1-25
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• 2020

This study analyzed key success factors of Korean car-sharing enterprises, Socar and Greencar, and the responsive strategies of Korean car-manufacturing company, Hyundai Motor Group, in the face of emerging sharing economy under the specific economic and regulatory system in Korea. The outcomes of the analysis are as follows. 'Timely market entry' in early startup phase and 'use of external resources' in early growth phase were key success factors common to both Socar and Greencar. However, the differences in the eventual business directions of the two companies also resulted in different key success factors in the expansion phase of their business. For Socar which focused on maintaining its independence and the external growth of B2C business, customer relation marketing and sufficient capital raising were key success factors. For Greencar which became a part of a business group and focused on improving the efficiency of business operations, timely market entry (B2B market) was key success factor. The use of external resources and cooperation with large corporations emerged as key success factors common to both companies in the rapid growth phase. The responsive strategies of the Hyundai Motor Group were collaboration, investment and direct management of DeliveryCar. The short-term goal of the responsive strategy was the operation of test-bed in collaboration with car-sharing company while the mid/long term goal was planning new mobility services by utilizing collected data. Securing opportunities for early market dominance for autonomous car industry was also found to be an important goal.

• Journal of Korea Multimedia Society
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• v.13 no.3
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• pp.378-391
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• 2010

In this paper, it is tested that an individual is able to be identified with finger face images and the results are presented. Special operators, FFG(Facet Function Gradient) masks by which the gradient of a facet function fit on a gray levels of image patches can be computed are used and a new procedure named F-algorithm is introduced to match the finger face images. The finger face image is divided into the equal subregions and each subregions are divided into equal patches with this algorithm. The FFG masks are used for convolution operation over each patch to produce scalar values. These values from a feature matrix, and the identity of fingers is determined by a norm of the elements of the feature matrices. The distribution of the norms shows conspicuous differences between the pairs of hand images of the same persons and the pairs of the different persons. This is a result to prove the ability of discrimination with the finger face image. An identification rate of 95.0% is obtained as a result of the test in which 500 hand images taken from 100 persons are processed through F-algorithm. It is affirmed that the finger face reveals to be such a good biometrics as other hand parts owing to the ability of discrimination and the identification rate.

• Journal of Korea Multimedia Society
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• v.12 no.3
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• pp.354-361
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• 2009

Shot change detection is the main technique in the video segmentation which requirs real-time processing and automatical processing in hardware. Until now, there were few research reports about real-time shot change detection for applying to hardware terminals with low performance such as PMPs(Portable Media Player) and cellular phones. In this paper, we propose shot change detection technique using adaptive threshold setting method on variable reference block. Our proposed algorithm determines shot change detection by comparing the feature value of current frame and a mean of a feature value on variable reference blocks. The proposed method can be used independently from the feature value of frame, can adaptively set thresholds using a mean of a feature value on variable reference blocks. We obtained better detection ratio than the conventional methods maximally by precision 0.146, recall 0.083, F1 0.089 in the experiment with the same test sequences. We verified real-time operation of shot change detection by implementing our algorithm on the PMP from some company of H. Therefore, our proposing algorithm will be helpful in searching video data on portable media players such as PMPs and cellular phones.

• Journal of Korea Multimedia Society
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• v.11 no.9
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• pp.1296-1301
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• 2008

Ultrasonography constructs pictures of areas inside the body needs in diagnosis by bouncing high-enorgy sound waves(ultrasound) off internal tissues or organs. In constructing an ultrasonographic image, the weakness of bounding signals induces noises and detailed differences of brightness, so that having a difficulty in detecting and diagnosing with the naked eyes in the analysis of ultrasonogram. Especially, the difficulty is extended when diagnosing muscle areas by using ultrasonographic images in the musculoskeletal test. In this paper, we propose a novel image processing method that computationally extracts a muscle area from an ultrasonographic image to assist in diagnosis. An ultrasonographic image consists of areas corresponding to various tissues and internal organs. The proposed method, based on features of intensity distribution, morphology and size of each area, extracts areas of the fascia, the subcutaneous fat and other internal organs, and then extracts a muscle area enclosed by areas of the fascia. In the extraction of areas of the fascia, a series of image processing methods such as histogram stretching, multiple operation, binarization and area connection by labeling is applied. A muscle area is extracted by using features on relative position and morphology of areas for the fascia and muscle areas. The performance evaluation using real ultrasonographic images and specialists' analysis show that the proposed method is able to extract target areas being approximate to real muscle areas.