• Journal of the Korean Operations Research and Management Science Society
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• v.41 no.2
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• pp.81-100
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• 2016

Much effort has been exerted to analyze online texts and understand how empirical results can help improve sales performance. In this research, we aim to extend this stream of research by decomposing online texts based on text sources, namely, companies and consumers. To be specific, we investigate how online texts driven by companies differ from those generated by consumers, and the extent to which both types of online texts have different effects on online sales. We obtained sales data from one of the biggest game publishers and merged them with online texts provided by companies using news articles and those created by consumers in user communities. The empirical analyses yield the following findings. Word visualization and topic analyses show that firms and consumers generate different contexts. Specifically, companies spread word to promote their own events whereas consumers produce online words to share winning strategies. Moreover, online sales are influenced by consumer-generated community topics whereas firm-driven topics in news articles have little to no effect. These findings suggest that companies should focus more on online texts generated by consumers rather than spreading their own words. Moreover, online sales strategies should take advantage of specific topics that have been proven to increase online sales. In particular, these findings give startup companies and small business owners in variety of industries the advantage when they use the online channel for distribution and as a marketing platform.

• Archives of Plastic Surgery
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• v.36 no.3
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• pp.299-305
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• 2009

Purpose: Recently, the incidence of malignant melanoma has been steadily increasing. Malignant melanoma is already known to have poorer prognosis than other primary skin cancers. Despite the poor prognosis, it is relatively less known to the public so that a number of patients visit hospital carrying advanced stage tumor. Yet, extensive study about malignant melanoma is currently insufficient, and specific guidelines and statistical figures in Korea are almost inexistent. Therefore, authors reviewed patients with malignant melanoma who have visited our hospital for last 14 years. Methods: Between January 1994 and January 2008, 62 patients were diagnosed with malignant melanoma at our hospital. A retrospective study was performed with data from patients' charts and biopsy results. Annual incidence, mean age of onset, gender, tumor location, tumor thickness, pathologic ulceration, clinicopathologic subtype, and clinical AJCC stage were evaluated. Analysis of factors associated with survival were performed using the Cox proportional hazard model. Kaplan - Meier method was used to generate survival curves. Results: Clinicopathologic features of 62 patients (32 male, 30 female) with average age of 57 years were evaluated. Most lesions were found in lower limb, and the most common subtype was acral lentiginous melanoma. We could also find that age, tumor thickness, and clinical stage were the only significant prognostic factors. Conclusion: Clinicopathologic features of malignant melanoma were analyzed in this study, but the result is not ready to be generalized because the number of cases is too small. Further study must be performed to report clinical guidelines for prognosis and treatment for malignant melanoma patients in Korea.

• Korean Journal of Remote Sensing
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• v.28 no.1
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• pp.55-67
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• 2012

Real-time image georeferencing is required to generate spatial information rapidly from the image sequences acquired by multi-sensor systems. To complement the performance of position/attitude sensors and process in real-time, we should employ on-line aerial triangulation based on a sequential estimation algorithm. In this study, we thus attempt to derive an efficient on-line aerial triangulation algorithm for real-time georeferencing of image sequences. We implemented on-line aerial triangulation using the existing Given transformation update algorithm, and a new inverse normal matrix update algorithm based on observation classification, respectively. To compare the performance of two algorithms in terms of the accuracy and processing time, we applied these algorithms to simulated airborne multi-sensory data. The experimental results indicate that the inverse normal matrix update algorithm shows 40 % higher accuracy in the estimated ground point coordinates and eight times faster processing speed comparing to the Given transformation update algorithm. Therefore, the inverse normal matrix update algorithm is more appropriate for the real-time image georeferencing.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.10
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• pp.760-765
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• 2013

PID (potential induced degradation) of PV module is the degradation of module due to the high potential difference between the front surface of solar cells and ground when PV modules operate under high humidity and temperature conditions. PID is generally derived from the positive sodium ions in front glass that are accumulated on P-type solar cells. Therefore, some papers for the electrical characteristic of only front components as glass, EVA sheet, solar cell under PID generation condition were revealed. In this paper, we analyzed the different outputs of module with PID by considering the all parts of module including the back side elements such as glass, back sheet. Mini modules with one solar cell were fabricated with the various parts on front and back sided of module. To generate PID of module in a short time, the all modules were applied.1,000 V in $85^{\circ}C$, 85% RH. The outputs, dark IV curves and EL images of all modules before and after experiments were also measured to confirm the main components of module for PID generation. From the measured results, the outputs of all modules with front glass were remarkably reduced and the performances of modules with back and front glass were greatly deteriorated. We suggest that the obtained data could be used to reduce the PID phenomenon of diverse modules such as conventional module and BIPV (building integrated photovoltaic) module.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.3
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• pp.1-10
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• 2020

In this paper, we propose an algorithm for estimating blood pressure using ECG (Electrocardiogram) and PPG (Photoplethysmography) signals. To estimate the BP (Blood pressure), we generate a periodic input signal, remove the noise according to the differential and threshold methods, and then estimate the systolic and diastolic blood pressures based on the convolutional neural network. We used 49 patient data of 3.1GB in the MIMIC database. As a result, it was found that the prediction error (RMSE) of systolic BP was 5.80mmHg, and the prediction error of diastolic BP was 2.78mmHg. This result confirms that the performance of class A is satisfied with the existing BP monitor evaluation method proposed by the British High Blood Pressure Association.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.4
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• pp.203-212
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• 2002

This study was conducted to remove the urban heat island effects embedded in the interpolated surfaces of daily minimum temperature in the Korean Peninsula. Fifty six standard weather stations are usually used to generate the gridded temperature surface in South Korea. Since most of the weather stations are located in heavily populated and urbanized areas, the observed minimum temperature data are contaminated with the so-called urban heat island effect. Without an appropriate correction, temperature estimates over rural area or forests might deviate significantly from the actual values. We simulated the spatial pattern of population distribution within any single population reporting district (city or country) by allocating the reported population to the "urban" pixels of a land cover map with a 30 by 30 m spacing. By using this "digital population model" (DPM), we can simulate the horizontal diffusion of urban effect, which is not possible with the spatially discontinuous nature of the population statistics fer each city or county. The temperature estimation error from the existing interpolation scheme, which considers both the distance and the altitude effects, was regressed to the DPMs smoothed at 5 different scales, i.e., the radial extent of 0.5, 1.5, 2.5, 3.5 and 5.0 km. Optimum regression models were used in conjunction with the distance-altitude interpolation to predict monthly normals of daily minimum temperature in South Korea far 1971-2000 period. Cross validation showed around 50% reduction in terms of RMSE and MAE over all months compared with those by the conventional method.conventional method.

• Design & Manufacturing
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• v.11 no.1
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• pp.45-49
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• 2017

Currently, a lot of efforts to make increases the manufacturing efficiency have tried and there is growing the interest to implementing the machining operation through CAM automation and optimization. This kind of movement has shown gradually in 5X milling as well as 3X milling task. By the way, in case of 5X milling, it is difficult to hire the CAM experts who is an experience for 5X machining and also it has too big trouble to use them due to high cost. For this reason, you can see the manufacturer who is concern the CAM S/W to provide the NC automation program that beginners can generate easily the 5X milling in short term and the existing 5X milling process can be improved. These requirements need to make a NC automation process including the practical machining strategies same as the generation by NC expert. In order to support this, it is necessary to directly apply the 3D machining part based on NC template which includes the machining procedures, standard cutter library, auto machine area selection, analyze tool for part shape, machining condition setting considering the material stiffness to be provided by CimatronE and it should be created the 5axis machining data by a minimized operation. With user-friendly, CimatronE's NC machining automation tools improve the 5-axis machining process and speed up the process, maximizing work efficiency and improving product productivity compared to existing machining tasks.

• Journal of Energy Engineering
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• v.19 no.2
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• pp.128-135
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• 2010

This paper introduces step by step procedures for the fabrication and operation of an embedded solar tracker. The system presented consists of application software, compactRIO, C-series interface module, analogue input module, step drive, step motor, feedback devices and other accessories to support its functional stability. CompactRIO that has a real-tim processor allows the solar tracker to be a stand-alone real time system which operates automatically without any external control. An astronomical method and an optical method were used for a high-precision solar tracker. CdS sensors are used to constantly generate feedback signals to the controller, which allow a solar tracker to track the sun even under adverse conditions. The database of solar position and sunrise and sunset time was compared with those of those of the Astronomical Applications Department of the U.S. Naval Observatory. The results presented here clearly demonstrate the high-accuracy of the present system in solar tracking, which are applicable to many existing solar systems.

• Journal of Environmental Impact Assessment
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• v.25 no.6
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• pp.525-531
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• 2016

This study integrates the Universal Soil Loss Equation(USLE) with GIS method to assess the soil erosion for national land cover map between 2007 and 2014. The land cover change map and C factors of USLE were applied to the estimation of spatial distribution of sediment yield. However, they generated distinct results because of differences in their applied methods and calculation processes of national land cover map. To generate the USLE model, C factors of MOE(Ministry of Environment) were compared with soil erosion of Inje stadium development area at the Naerin watershed in Gangwon province to 2014. The several thematic maps of research area such as land cover map, topographic and soil maps, together with tabular precipitation data used for soil erosion calculation. The land cover change were carried with level-2 and high level land cover map of MOE and estimated maximum double of soil erosion.

• Korean Institute of Interior Design Journal
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• v.17 no.6
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• pp.143-151
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• 2008

This paper inquires the elements of emotional design and the current conditions of its application in order to examine the particularities arise when planning emotional interior design for a women's clinic. Research was done by studying plans for elements of emotional interior design while site investigation was done to find out the status of women's clinic lobby. Six women's clinic in Ulsan were chosen as subjects while survey was done based on the studied emotional plan elements. The data evaluation was classified by the installed properties and substituted with image scale using emotional mensuration. The outcome is as follows; First, elements of emotional interior design was composed of elements making up the space's comfort and aesthetic appreciation, and elements stimulating human's five senses leading to psychological treatment. Therefore, the plan for interior design should merge the design elements that stimulate senses and social elements into one unified concept. Second, the composited elements within the plan should strive to stimulate sights by contracts and changes and add symbolic or meaningful elements based on the principles of design. In so doing, the plan should incorporate an aesthetic orderliness and a coherent image. Third, the interior of women's clinics should not only have psychological comfort but also liveliness and ease that suits 20-30 old women. To conclude, Color, form, finishing materials and texture should be selected with a unified style in mind and the plan itself should strive to generate playfulness though harmonious coordination.