• The Journal of Information Systems
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• v.25 no.3
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• pp.91-116
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• 2016

Purpose Quality and quantity of knowledge in virtual communities is at the discretion of knowledge contributors, and understanding what motivates knowledge contributors' behavior can be invaluable. The purpose of this paper is to find the social aspect of knowledge contribution in virtual communities within the frame of self-determination theory. Also, we seek differential effects of motivation value for novice vs. expert knowledge contributors. Design/methodology/approach Reputation and altruistic motives are studied as antecedents of intrinsic and extrinsic values in contributing knowledge in virtual communities. Gained social connectedness and satisfaction in their knowledge were behaviors studied as dependents of the motivational value. Also, the proposed model was tested for group differences between expert and novice knowledge contributors seeking motivational changes. Self-determination theory is the base theory which explains how externally motivated behaviors can evolve from extrinsically motivated to intrinsic-like behavior with social experiences as knowledge contributors. Findings Analysis of 262 data points gathered from knowledge contributors in Korean virtual communities in 2005 reveals social connectedness as an important dependent variable both for novice and expert knowledge contributors. Group difference analysis shows altruism has negative influence on extrinsic value only for experts. Intrinsic value has a positive influence on satisfaction for both groups alike but the expert group shows a statistically stronger influence than the other.

• Journal of Korean Academy of Nursing
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• v.26 no.1
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• pp.15-32
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• 1996

The clinical practice program for home care nurses was implemented in June 1994, to help to set up a hospital-based home care system in the Kwangju City area as a collaborative work between the Department of Orthopedic Surgery at Chunnam University Hospital and Chunnam University School of Nursing. Under the developed clinical practice strategy, the eight week training was given to five licensed home care nurses who had completed Part I and II of the home health care nursing practicum from June 1994. The purpose of this descriptive evaluation study was to identify the effectiveness of the clinical practice program for home care nurses specialized in the area of patient care for people with musculoskeletal function impairment. As a method in data analysis, data triangulation was used in the five home care nurse case evaluations. The variety of data analyzed include confidence score by home care nurse self-evaluation, patient and family member satisfaction scores, and competency score by preceptor evaluation. The study findings revealed that an increase rate in nursing performance didrate necessarily coincide with an increase not in competency score and also, not with the patient /family member satisfaction scores. And an order derived from the clinical performance scores of five home care nurses corresponded to those from three measurements-competency score, patient satisfaction score, and family member satisfaction score. However, it differed from the order associated with the confidence score. Consistency derived from the three objective evaluation methods may lead to the possibility that the level of competency measured by educator can be further explained by the levels of patient/family member satisfaction. The salient finding of this study was that, in case of nurse A who have had little clinical experience in the orthopedic patient care, there was a significant increase in the level of confidence and competency in subscale of professional skill with the home care clinical practice. Therefore, the effect of the clinical practice program would be successful for nurses who have had little experience in the area of specialization. The study results suggest that there might be some time difference in the development of cognitive sense (confidence) in performance and actual clinical performance (competency). In future research, relationships between the confidence and competency score, and between the confidence score and the patient satisfaction score should to be measured in different time frame to achieve a better explanation power of the study outcome.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1742-1754
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• 1999

In this paper, we propose a rate control scheme, using histogram based rate-distortion (R-D) estimation, which produces a consistent picture quality between consecutive frames. The histogram based R-D estimation used in our rate control scheme offers a closed-form mathematical model that enable us to predict the bits and the distortion generated from an encoded frame at a given quantization parameter (QP) and vice versa. The most attractive feature of the R-D estimation is low complexity of computing the R-D data because its major operation is just to obtain a histogram or weighted histogram of DCT coefficients from an input picture. Furthermore, it is accurate enough to be applied to the practical video coding. Therefore, the proposed rate control scheme using this R-D estimation model is appropriate for the applications requiring low delay and low complexity, and controls the output bit-rate ad quality accurately. Our rate control scheme ensures that the video buffer do not underflow and overflow by satisfying the buffer constraint and, additionally, prevents quality difference between consecutive frames from exceeding certain level by adopting the distortion constraint. In addition, a consistent considering the maximum tolerance BER of the voice service. Also in Rician fading channel of K=6 and K=10, considering CLP=$10^{-3}$ as a criterion, it is observed that the performance improment of about 3.5 dB and 1.5 dB is obtained, respectively, in terms of $E_b$/$N_o$ by employing the concatenated FEC code with pilot symbols.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.5
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• pp.654-664
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• 2006

Statement of problem: There has been a eat interest in the use of titanium for fixed and removable prostheses in recent because of its excellent biocompatibility. However, the melting temperature and chemical reactivity of titanium necessities casting system different from those used in conventional casting. The current titanium casting systems are based on an electric-arc design for melting the metal in an argon atmosphere and its exclusive investment. Despite the new development in Ti casting system, inadequate mold filling and internal porosity are frequently observed casting defects. Purpose : The purposes of this study were to compare the castibility and reaction layer of the casting titanium under the two casting machines and their investment condition. Material and method: coping and machine-milled titanium coping according to the casting methods and the marginal configurations. The total 28 specimens were used, and these are divided into 4 groups according to 2 casting machines and 2 investments. The castings were analyzed using x-ray microanalysis and microhardness testing. The reaction layer between margin of titanium casting and the investments was observed and analyzed with scanning electron microscope. Result: 1. Castabiliy of casting titanium specimen was best in the group of centrifugal casting machine and Selevest $CB^{\circledR}$ and good that of Selevest CB and pressure differential casting machine, Rematitan plus and centrifugal casting machine, Rematitan plus and pressure differential casting machine in order. 2. There was no significanct correlation in titanium castability in respect of casting machine. However ANOVA indicated that Selevest $CB^{\circledR}$ groups had significantly better castability than Rematitan $plus^{\circledR}$ groups.(p<0.05) 3. There was a significant microhardness difference between centrifugal casting machine groups and pressure differential groups.(p<0.05) Titanium castings in centifugal groups had significantly harder than those in pressure differential groups. 4. The addition of zirconia decreased interfacial reactivity. Conclusion: above result revealed that of the castability of titanium casting specimens had little correlation in casting machines and was better in magnesia-based investment contained ZrO2 groups. However in order to practice casting titanium in clininic, its castability should be improved, also there should be more research on factor of castability so that long-span prothesis and removable partial denture metla frame may be casted completly.

• Korean Journal of Agricultural Science
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• v.38 no.3
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• pp.505-512
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• 2011

Structural characteristics for standard models of single-span plastic greenhouse in Korea and high tunnels in North America were analyzed, and comparative analysis for greenhouse environments measuring in Korean farmhouse and Rutgers high tunnel was carried out to find structural and environmental improvements of single-span plastic greenhouses that occupy most of Korean greenhouse. Widths of high tunnels are similar to single-span plastic greenhouses but their heights are high comparatively and their side heights are fairly higher than single-span plastic greenhouses specially. Rafters, which are main frames, section sizes of high tunnels are bigger and their intervals are wider than single-span plastic greenhouses. Relative bending resistances compared with representative Korean greenhouse were analyzed by 0.92 to 1.42 in single-span plastic greenhouses, and 1.38 to 2.96 in high tunnels. Frame ratios of single-span plastic greenhouses were 6.8 to 8.6%, and those of high tunnels were 5.5 to 8.7%. We analyzed air temperatures and solar radiations measured in single-span plastic greenhouse and high tunnel on clear days in late March. There were outside temperatures in generally similar range, and judging by rise of indoor temperatures, ventilation performance of high tunnel is more excellent than single-span plastic greenhouse. Solar radiations of two areas were no big difference but light transmittance of high tunnel was a little bit higher than single-span plastic greenhouse. Single-span plastic greenhouses are disadvantageous in environmental managements such as ventilation performance and light transmittance because distance between greenhouses is too narrow and length of greenhouse is too long compared to high tunnels. To get the environmental improvement effects as well as to increase the structural resistance of single-span plastic greenhouses are achievable by widening the width of greenhouse in possible range, widening the space between rafters, and enlarging the section size of rafters. Also, we need to secure enough distance between greenhouses and to restrict the length of greenhouse by maximum 50 m in order to improve the ventilation performance and the light transmittance.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.293-297
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• 2018

The purpose of this study was to determine the influence of video modeling observational learning intervention on the learning and performance of a bowling skill in adolescents with intellectual disabilities. Thirty special middle school students whose ages ranged from 14 to 16 years were recruited from Daegu, Korea. Intellectual disabilities of the participants were assessed by Korean version of the Wechsler intelligence scale for adolescent and a social maturity scale. During the experiment, participants repeatedly watched the one-minute action observation film for three minutes before beginning each frame and played 60 frames. Statistical comparisons were performed using a 2 (groups) ${\times}$ 6 (trials) ANOVA, with repeated measures on the last factor of the acquisition stage (p<0.05). Factors of the retention stage scores were analyzed by one-way ANOVA. The sources of any significant main effects were tested using a Tukey's HSD (honest significant difference) approach. SPSS 21.0 was used for statistical analyses. The performance scores of the action observation group were significantly higher than those of the control group. The findings showed that observational learning in the form video modeling has the potential to enhance acquisition and learning of a bowling sport skill in intellectual disability individuals; however, these findings are limited to adolescents with moderate intellectual disabilities.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.4
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• pp.10-21
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• 2008

The present paper propose a real-time moving object recognition and tracking method using the wavelet-based neural network and invariant moments. Candidate moving region detection phase which is the first step of the proposed method detects the candidate regions where a pixel value changes occur due to object movement based on the difference image analysis between continued two image frames. The object recognition phase which is second step of proposed method recognizes the vehicle regions from the detected candidate regions using wavelet neurual-network. From object tracking Phase which is third step the recognized vehicle regions tracks using matching methods of wavelet invariant moments bases to recognized object. To detect a moving object from image sequence the candidate regions detection phase uses an adaptive thresholding method between previous image and current image as result it was robust surroundings environmental change and moving object detections were possible. And by using wavelet features to recognize and tracking of vehicle, the proposed method decrease calculation time and not only it will be able to minimize the effect in compliance with noise of road image, vehicle recognition accuracy became improved. The result which it experiments from the image which it acquires from the general road image sequence and vehicle detection rate is 92.8%, the computing time per frame is 0.24 seconds. The proposed method can be efficiently apply to a real-time intelligence road traffic surveillance system.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4285-4289
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• 2015

Purpose: Blood hemoglobin levels are known to influence response to radiotherapy. This retrospective analysis compared the effect of hemoglobin levels upon response to radiation among patients treated with radiation alone (by accelerated hyperfractionated radiotherapy) versus those treated with concurrent cisplatin chemoradiotherapy. Materials and Methods: Among patients treated for locally advanced carcinoma of the cervix (LACC) during 2009-10, a total of 60 fulfilled the eligibility criteria. In this time frame, external beam radiotherapy was delivered with either concurrent chemoradiotherapy (CRT, n=31) (45Gy over 25 fractions, with weekly cisplatin at 40mg/m2), or with accelerated hyperfractionated radiotherapy (AHRT, n=29) (20Gy over 10 daily fractions over the first two weeks, followed by 30Gy over 20 fractions over the next two weeks, with two fractions of 1.5Gy per day, without the use of chemotherapy). Mean weekly hemoglobin (MWH) levels of all patients were calculated as the arithmetic means of weekly recorded blood hemoglobin levels. As per MWH, patients in both of the AHRT or the CRT groups were classified into two subgroups-those with MWH between 10-10.9g/dL, or with MWH>11g/dL. Complete response (CR) to external beam RT phase (prior to brachytherapy) was declared after clinical examinations and computed tomography. The CR rate was noted for both MWH sub-groups within each of the AHRT and CRT groups. Results: Within the AHRT group, patients with MWH>11g/dL had a much better CR rate in comparison to those with MWH:10-10.9g/dL (80% vs. 21.1%) which was statistically significant (p 0.0045). Within the CRT group, there was no significant difference in the outcomes within the MWH>11g/dL and MWH:10-10.9g/dL sub-groups (CR rates of 80% vs. 61.9%, p=0.4285). Conclusions: The importance of maintaining a minimum hemoglobin level of 11g/dL during RT is much greater for patients treated with RT alone, than for patients treated with concurrent chemoradiotherapy. Enhanced haemoglobin levels during RT may to an extent negate the ill-effects that may otherwise arise due to non-use of concurrent chemotherapy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.200-207
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• 2017

3D printing is making a huge difference to existing industries and is beginning to be applied in the field of construction. 3D printing construction differs from existing construction techniques. Therefore, new construction processes need to be developed. In particular, the accurate construction duration is linked directly to a successful project. A method for estimating the construction duration for 3D printing construction is necessary. In this study, a 3D printing construction process and duration estimation method were derived to prepare for the future introduction of 3D printing in construction. The scope of the study was assumed to be 3D printing equipment capable of pouring concrete, and limited to a frame structure construction. The developed construction period estimation method was applied to the virtual test model. As a result of applying the test model, the construction duration was shortened by approximately 50% compared to the existing construction technique. The method of estimating the construction period developed in this study can be applied to 3D printing constructions in the future and help establish a business plan.

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.338-342
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• 1994

Pulmonary clearance of Tc-99m-DTPA(PCD) has been used for the measurement of polmonary epithelial permeability. It has been reported to be increased not only in variety of polmonary diseases including ARDS, interstitial fibrosis, and smokers, but also in normal subjects on positive end expiratory pressure respirator, or after exercise. It was also noted that decrease of pulmonary blood flow due to pulmonary arterial obstruction results in delayed PCD. Normal range of PCD varies with institutes. We prospectively measured PCD in 17 normals (5 males and 12 females) consisted of staffs and trainees in the department of radiology of Kangnam St. Mary's hospital using original Bark Nebulizer (India). Age ranged from 32 to 43 years. 370 MBq of Tc-99m-DTPA was inhaled in supine position and supine posterior images were subsequently obtained with 1 min/frame, $64{\times}64$ matrix and word mode for 30min. Regions of interest were set on each lung, whole lungs, and upper, middle and lower thirds of right lung, respectively. Best fit regression curve was obtained by least square method from initial 7min after peak activity on each curve and time for half clearance of maximum activity (t1/2) was calculated. Mean t1/2 was $51{\pm}11.2min$ for whole lung. There was no significant difference between t1/ 2 of right and left lungs. Initial uptake was higher in the lower third and t1/2 was shorter in the lower third than in the upper third(P<0.05). We reviewed several reports on PCD and compared our data with the others. In this study, faster clearance in the lower third may be due to the position imaged with or the environment the subjects belong to, and further investigation is under way.