• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.9
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• pp.895-900
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• 2012

This paper aims to examine the effect of nanodroplets on pool-type absorption heat transfer enhancement and to find the relationship between the dispersion stability and the absorption performance. The concentrations of oil and surfactant are considered as the key parameters. $C_{12}E_4$ and Tween20 are used as the surfactants and N-decane oil is added to the $NH_3/H_2O$ solution to make the binary nanoemulsion fluids. Binary nanoemulsion fluids are dispersed by the ultrasonic vibrator and the stirrer under specific conditions. The dispersion stability of binary nanoemulsion fluids for each oil concentrations is evaluated from the droplet size and Tyndall effect analysis. The absorption performance of binary nanoemulsion fluids is compared with the result of dispersion stability. In addition, it is found that the binary nanoemulsion fluid is a strong candidate as a new working fluid for absorption applications.

• Information Systems Review
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• v.6 no.1
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• pp.123-139
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• 2004

It is needed to transfer the technology actively which has already developed to improve a up-to-date technology and foster the technological innovation. The technology transfer also can bring about a commercial success. To promote the technology transfer, it is needed to develop a new technology valuation model for a specific technology from a objective point of view, as well as to equip an institution such as the technology transfer center. The technology valuation from a objective point of view is of importance as the basic information for the price negotiation between a technology-buyer and a technology-seller. This paper takes aim at investigating a new technology valuation model and developing a technology valuation system for promoting the technology transfer. A new technology valuation system is developed as a Web-enabling base. Using this users are able to estimate the value of a specific technology on a real time efficiently.

• Journal of Animal Environmental Science
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• v.1 no.2
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• pp.125-136
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• 1995

To use the earth heat for the pig housing, an underground heat exchanger has constructed in depth of 2.5m and 20m length. The temperature of the outlet air was max. 8 kelvin higher than that of inlet air in winter season. In spite of the -7$^{\circ}C$ outside temperature, it could keep the air temperature from the earth tube above zero degree. The heating performance was maximum in value of 3.25Wh/㎥ and average of 1.75Wh/㎥ by the airflow volume of 340㎥/h. The slope of relative humidity from outlet air has shown gentler than that of inlet air. By using the underground heat exchanger, it would be possible to prepare an relatively uniform relative humidity in the swine stalls. The temperatures on the earth, where PVC pipes are buried, have shown 10~12$^{\circ}C$ on March. This can reduce the difference between day and night temperature during this season by using the underground heat exchanger.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.583-592
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• 2016

IMO (International Maritime Organization) in the UN (United Nations) set up that aim at reducing $CO_2$ emission from ship by up to 30 percent until 2030. The final purpose of this study is the development of marine thermoelectric generation system using waste heat from vessel of internal combustion engines. Before the development of marine thermoelectric generation system, this paper carried out the fundamental heat analysis of marine thermoelectric generation system. It was able to obtain the valuable results about the efficiency improvement of the thermoelectric generation system. The results is as follows : 1) It was confirmed that the efficiency of thermoelectric generation system improves to 8.917 % with increasing the temperature difference of peltier module by reducing the temperature difference between peltier module and heat source at the hot side. 2) System efficiency according to change in the external load resistance was confirmed that the change width of about 6 % which does not significantly occur. 3) System efficiency in the case stainless steel at the same condition is 8.707 %. System efficiency could be confirmed that the stainless steel is higher than duralumin (8.605 %), copper (8.607 %).

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.5
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• pp.468-474
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• 2012

In this study, experimental studies were performed for the carbon nanomaterial(CNM) which is catching on as a material for eco-ship. The opposed-flow methane flame was used as a heat source for synthesis of CNM. Ferrocene was used as a catalyst for the synthesis of CNM. These major parameters were $H_2$ mixing rate and sampling positions that synthesize CNMs in opposed-flow diffusion flames. The propensities of CNMs were experimentally determined using SEM and TEM images. The experimental result showed that the amount of CNTs was increased with increasing $H_2$ concentration. It can also be found that the optimal temperature in opposed-flow methane flame for synthesis of CNT was about 1500 K.

• Anxiety and mood
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• v.9 no.1
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• pp.38-44
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• 2013

Objective : The end-stage renal disease patients who shared fear of death, functional impairment due to hemodialysis are vulnerable to depression, anxiety and other mental problems. It is possible that their psychiatric characteristics and related autonomic nervous functions have some differences depending on their age. We purpose to find the differences of psychiatric characteristics and related autonomic nervous functions between adult and elderly hemodialysis patients. Methods : Our subjects are end-stage renal disease hemodialysis patients composed of 39 adults (<65 years) and 24 seniors (${\geq}65$ years). Outcome measures included the 17-item Hamilton Rating Scale for Depression, The Hamilton Rating Scale for Anxiety, The Apathy Evaluation Scale and Mini-International Neuropsychiatric Interview by clinician. And subjects fulfilled self-report scale, The Positive thinking scale and The Snaith-Hamilton Pleasure Scale. The autonomic nervous functions are measured by heart rate variability. Results : There are no significant differences in demographic factors between two groups. The 17-item Hamilton Rating Scale for Depression, The Hamilton Rating Scale for Anxiety, The Apathy Evaluation Scale, The Snaith-Hamilton Pleasure Scale and autonomic nervous functions are also not different. But only positive thinking scale is higher in adult hemodialysis group than the elderly (F=5.395, p=0.024). Conclusion : This study compared depression, anxiety and autonomic nervous functions between adult and senior hemodialysis patients. There are no significant differences in psychiatric characteristics and autonomic nervous functions between two groups except positive thinking traits. Senior patients endured their chronic disease similar to adult patients did in spite of their old age. This result suggests that elderly's higher positive thinking traits affect their endurances about the negative situations.

• Clean Technology
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• v.20 no.3
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• pp.321-329
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• 2014

In this study, Indonesia low rank coal, which has moisture content of around 26%, is dried less than 5% by using a laboratory-scale (batch type) steam fluidized-bed dryer in order to produce the low-moisture, high rank coal. Normally, CCS (carbon capture and storage) process discharges $CO_2$ and steam mixture gas around $100-150^{\circ}C$ of temperature after regeneration reactor. The final purpose of this research is to dry low rank coal by using the outlet gas of CCS process. At this stage, steam is used as heat source for drying through the heat exchanger and $CO_2$ is used as fluidizing gas to the dryer. The experimental variables were the steam flow rate ranging from 0.3 to 1.1 kg/hr, steam temperature ranging from 100 to $130^{\circ}C$, and bed height ranging from 9 to 25 cm. The characteristics of the coal, before and after drying, were analyzed by a proximate analysis, the heating value analysis and particle size analysis. In summary, the drying rate of low rank coal was increased as steam flow rate and steam temperature increased and increased as bed height decreased.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.5
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• pp.483-490
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• 2016

In plant industry, sulfur storage tank is made of steel and annular plate is connected with concrete foundation of ring wall type by anchor bolt. Due to keep sulfur at high temperature in tank by coil, sulfur storage tank is expanded larger than another tank stores fluid at room temperature. Generally, structural design of tank foundation is performed analysis with loading of temperature gradient between inner and outer surface, this method can't consider the phenomenon that load is intensively transferred to concrete foundation at anchor bolt. This means that temperature load is underestimated and causes crack of concrete near anchor bolt. In this study, evaluation formula considering temperature load transfer mechanism through anchor bolt is proposed and load acting on concrete foundation is rationally decided. For this purpose, it is analyzed variation of thermal load per various anchor bolt number using finite element model including tank annular plate and anchor bolt. Solution is proposed as specified term combining result of analysis and theoretical solution for evaluating load transferred by anchor bolt. For confirmation of validation of proposed formula, it is applied in design of sulfur storage tank at plant site, it shows that the formula can be practically applied.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.3
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• pp.55-62
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• 2012

EZW, also known as Embedded Zerotree Wavelet, is a technique that allows transforming original images into wavelet, then again compressing images using the transformed data. This algorithm demonstrates a simple structure and remarkable effectiveness. This paper has reformed the EZW to improve a compression efficiency. Fundamentally, EZW evaluates the priority level of wavelet-transformed data and stores them into four different categories considering the priority level of the data as well as their location information. The four categories are represented as the symbols P, N, Z, and T. Here, P and N correspond to the volume of data and the priority level whereas Z and T show the location information of data. Each letter is stored through the process of dominant pass. However, here is when the data of Z and T are stored redundantly which lead to unnecessary increase of data volume. In this paper, we propose a modified version of Embedded Zerotree Wavelet algorithm, which is designed to efficiently reduce the volume of redundantly stored data using four additionally inserted symbols. We name it EEZW, Extended Embedded Zerotree Wavelet. The proposed algorithm demonstrates the efficiency verified by a number of image and confirms an outstanding result through the PSNR(Peak Signal To Noise Rate) values, which measure their quality of images.

• Journal of Yeungnam Medical Science
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• v.23 no.2
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• pp.193-204
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• 2006

Purpose: Various postoperative adjuvant chemotherapy regimens have been proposed for the patients with advanced gastric cancer. The majority of clinical trials have shown no significant difference in the survival benefit. The aim of this study was to compare the survival rates of postoperative adjuvant chemotherapies used in stage III gastric cancer patients who received curative gastrectomy. Materials and Methods: Between 1990 and 1999, a survival analysis was performed in 260 patients who received curative gastric resection and postoperative adjuvant chemotherapy. The patients were divided into four groups according to the chemotherapeutic regimens received. The groups were: the F group: furtulon alone, FM group: furtulon and mitomycin, FAM group: 5-FU, adriamycin and mitomycin, FLEP group: 5-FU, leucovorin, etoposide and cisplatin. The survival rates were analyzed using the Kaplan-Meier method and the Cox proportional hazards model. Results: There were no differences among the groups of patients with regard to tumor characteristics except for lymph node metastasis and the ratio of metastasis to lymph nodes. In the FLEP group, the ratio of metastasis to lymph nodes was higher than in the other groups. The five and ten year survival rates of F, FM, FAM and FLEP were 51.9%, 28.9%, 59.5%, 49.8%, 66.1%, 57.4% and 30.0%, 27.5%, respectively. The univariate analysis showed that age, Borrmann type, lymph node metastasis, ratio of metastasis to lymph nodes, postoperative adjuvant chemotherapy and recurrence were significant factors for survival. For the multivariate analysis, recurrence, age, Borrmann type, ratio of lymph node metastasis and lymph node dissection were independent prognostic factors; however, the postoperative adjuvant chemotherapy was not an independent prognostic factor. Conclusion: The FAM regimen was the most beneficial postoperative adjuvant chemotherapy for improved survival rates; the FM regimen was the second and the FLEP regimen was the last. In order to determine the effectiveness of postoperative adjuvant chemotherapy in stage III gastric cancer, well designed prospective studies including a surgery only group will be needed.