• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.342-349
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• 2000

This paper demonstrates the influence of intensity of the monsoon on morpho-hydrological fluctuations in Taechung Reservoir during 1993${\sim}$1994. During the study, hydrological variables including rainfall, inflow, and discharge volume showed distinct contrast between 1993 and 1994. Interannaul differences in rainfall occurred during the monsoon in July${\sim}$August monsoon and influenced inflow, discharge, and water residence time (WRT). Total inflow in 1993 was four times greater than that of 1994, and summer inflow in 1993 was 8 times greater than summer 1994. Annual Mean WRT was 93.2 d in 1993 vs. 158.6 d in 1994 and the largest differences occurred between monsoons of 1993 and 1994. Morphometric variables reflected the interannual contrasts of hydrology, so that in 1993 surface area, total volume, shoreline development, and mean depth increased consistently from premonsoon to postmonsoon and over this same period in 1994 they decreased. This outcome indicates that the area of shallow littoral zones in 1993 was greater than in 1994. Also, the drainage area to surface area (D/L) at 80 m MSL was 60.7 which was much greater than values in Soyang and Andong reservoirs and natural lakes world-wide. The morpho-hydrodynamic conditions seemed to influence in-reservoir nutrient concentration which is one of the most important factors regulating the eutrophication processes. I believe, under the maximum hydrodynamic fluctuations in Korean waterbodies during the monsoon, applications of mass balance models to man-made lakes for assessments of external loading should be considered because the models can be used under the seasonally stable inflow and water residence time.

• Journal of KIISE:Software and Applications
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• v.36 no.1
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• pp.21-29
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• 2009

An intelligent service robot is a robot that monitors its surroundings, and then provides a service to meet a user's goal. It is normally impossible for a robot to anticipate all the needs of its user and various situations in the surroundings ahead, and to prepare for all the necessary functions to cope with them. Therefore, it is required to support the self-growing capability by which robots can extend their functionality based on users' needs and external conditions. In this paper, as an enabler of the self-growing capability, we propose a method that allows a robot to select a component-composition pattern represented in an architectural form (called a sub-architecture), and to extend its functionality by obtaining a set of software components that are prescribed in the pattern. Sub-architecture is selected and instantiated not only based on the functionality required but also based on quality requirements of a user and the surrounding environment. To provide this method, we constructed a quality-attributes-in-use ontology and developed a brokering mechanism that matches quality requirements of users and surroundings against quality attributes of sub-architectures. The ontology provides the common vocabularies to represent quality requirements and attributes, and enables the semantically-based reasoning in matching and instantiating appropriate sub-architectures in supporting services to users. This ontology-based approach contributes to provide a great flexibility in extending robot functionality based on available software components, and to narrow the gap between users' Quality requirements and the Quality of the actual services provided by a robot.

• Herbal Formula Science
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• v.28 no.3
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• pp.289-300
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• 2020

Objectives : In this paper, We pointed out medico-historical meaning of Hyang'yak Kugŭppang (鄕藥救急方, Medical Recipes of Local Botanicals for Emergency Use), a medical book of Koryŏ Dynasty, breaking from the existing analysis view based on Hyang'yak (鄕藥), local herbs produced in Korean Peninsula. Methods : For that purpose, we analyzed the clinical characteristics of the diseases and symptoms, strategies of treatment, therapeutic tools, drug formulations, composition of herbal formulas in Hyang'yak Kugŭppang. Results : The following characteristics were confirmed in Hyang'yak Kugŭppang. First, it contained a way to cope with the diseases and symptoms that do not have to check the exterior, interior, cold, and heat. Also, it introduced basic strategies such as reducing, facilitating flow, draining downward, warming, or tonifying, etc. It mainly included herbal medicine as the therapeutic tools, and introduced formulas composed by single herb than complex recipes. It suggested external applications more than internal use, and proposed formulations in the form of decoctions or powders, etc. The herbs of formulas were used by experience without explanations of nature & taste, efficacy of each herbs. Conclusions : Hyang'yak Kugŭppang is a book of medical recipes for emergency use that has been distributed to help gentries, even if they do not have professional medical knowledge, to instantly cope with diseases and symptoms with medicines that are easy to obtain. Previous researches has analyzed the value of Hyang'yak Kugŭppang as a collection of information of hyang'yak, and used it as a historical basis of the uniqueness of Korean medicine. Since Hyang'yak Kugŭppang is not a book specialized for herbs, but rather a clinical medical book that introduces recipes for specific symptoms of diseases, if we pay attention to the clinical characteristics of Hyang'yak Kugŭppang, it will provide an opportunity to describe Koryŏ or Korean medicine in a new way.

• Science of Emotion and Sensibility
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• v.5 no.4
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• pp.77-84
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• 2002

In this paper, we propose the NAVER, a general framework for multipurpose virtual environments, and introduce the case study of evaluating car prototypes using cave-like systems. As a framework to implement variant applications in virtual environment, NAVER is extensible, reconfigurable and scalable. NAVER consists of several external modules (Render Server, Control Server and Device Server), which communicate each other to share states and user-provided data and to perform their own functions. NAVER supports its own scripting language based on XML which allows a user to define variant interactions between objects in virtual environments as well as describe the scenario of an application. We used NAVER to implement the system for evaluating car prototyes in a CAVE-like virtual environment system. The CAVE-like virtual environment system at KIST consists three side screens and a floor screen (each of them is a square with side of 2.2m), four CRT projectors displays stereoscopic images to the screens, a haptic armmaster, and a 5.1 channel sound system. The system can provide a sense of reality by displaying auditory and tactile senses as well as visual images at the same time. We evaluate car prototypes in a CAVE-like system in which a user can observe, touch and manipulate the virtual installation of car interior.

• Analytical Science and Technology
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• v.28 no.1
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• pp.33-39
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• 2015

CdS-QD particles are a nano-sized semiconducting crystal that emits light. Their optical properties show great potential in many areas of applications such as disease-diagnostic reagents, optical technologies, media industries and solar cells. The wavelength of emitting light depends on the particle size and thus the quality control of CdS-QD particle requires accurate determination of the size distribution. In this study, CdS-QD particles were synthesized by a simple ${\gamma}$-ray irradiation method. As a particle stabilizer polyvinyl pyrrolidone (PVP) were added. In order to determine the size and size distribution of the CdS-QD particles, sedimentation field-flow fractionation (SdFFF) was employed. Effects of carious parameters including the the flow rate, external field strength, and field programming conditions were investigated to optimize SdFFF for analysis of CdS-QD particles. The Transmission electron microscopy (TEM) analysis show the primary single particle size was ~4 nm, TEM images indicate that the primarty particles were aggregated to form secondary particles having the mean size of about 159 nm. As the concentration of the stabilizer increases, the particle size tends to decrease. Mean size determined by SdFFF, TEM, and dynamic light scattering (DLS) were 126, 159, and 152 nm, respectively. Results showed SdFFF may become a useful tool for determination of the size and its distribution of various types of inorganic particles.

• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.106-117
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• 2012

The proportion of rebar factory manufacturing which has been settled down in Korea recently seems to increase because of their strength such as high decreasing rate of rebar loss and manufacturing accuracy and the external factors such as an increase of downtown projects and a decrease of skilled workers. However, factory manufacturing using straight rebars causes a certain amount of rebar loss and an environmental problem including $CO_2$ emissions. To solve these problems, Bar in coil (BIC) has been introduced; however its application is very rare because it has not been produced so far in Korea and manufacturing machines of BIC are very expensive. Also, although BIC's application is expected to expand due to its strengths, few analysis of its application has been conducted. Therefore in this study, analysis of the BIC's characteristics and the influence to the rebar manufacturing industry are conducted for the advancement of rebar work as a basic research. To achieve this, inquiry on the present condition of rebar manufacturing industry in Korea is implemented. Then, the validation of BIC's applications by aspects of industry and the analysis of stakeholders' economical profit and loss are conducted.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.4
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• pp.533-540
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• 2012

The use of wind energy is gaining importance because of its many advantages. Nations worldwide are promoting the installation of wind farms to produce electricity in an attempt to tackle climate change and increasing oil costs. But, wind turbines can generate undesired signals which disturb the performance of military radar systems. Because the current generation of on and off-shore three bladed wind turbines have radar signatures consistent with their very large physical size. So this study considers the options available for the reduction of wind turbine radar signature and presents solutions for each of the main external turbine components. The radar signature reduction approaches are based on existing technologies developed for aerospaces stealth applications. However, the realization of these for the purposes of reduction wind turbine radar signatures is a novel development, particularly in the solutions proposed. This paper is presented techniques which reduce radar signatures of wind turbine. We know that radar signatures of wind turbine reduce by using these techniques.

• YAKHAK HOEJI
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• v.58 no.6
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• pp.378-386
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• 2014

Topical agents including of steroids are easily exposed to Korean patients in community setting. Those topical agents must be use cautiously because can cause adverse drug reaction unlike other oral medication. We evaluate the using pattern topical agents of Korean in community setting. We performed a questionnaire survey in three different pharmacies (general community pharmacy, dermatology clinic oriented pharmacy, general hospital oriented pharmacy) and in three university town. The survey asked necessity of topical agents, the number of applications per day, application period, site, and exist of steroids ingredient, etc. Total 330 people was participated in the survey from May 1st to July 31st, 2014. We analysed the survey by the frequency of each question and cross-analysis of the compliance between general public and pharmacy groups. In results, Korean people used topical agents for sudden skin diseases (66.9%), was gotten by dermatologist's prescription (89.1%), and did not know their diagnosis (39.2%). The people applied topical agents on face (22.3%), less one half FTU (finger tip unit) per application (61.9%), less than one week (62.9%). Though they was received drug education from pharmacist (52.2%), did not heard about adverse effects (78.4%). And compliance of applied times in pharmacy group was higher than in-non-pharmacy group (56% vs 38%, p=0.002). The highest compliance between 3 pharmacy subgroup was general community pharmacy (76.3% vs 61.6%, 61.2%, p=0.039). Compliance of applied duration was no difference between groups. Majority of respondents did not know diversity of ingredients, potency, application area of topical steroids, and replied to feel some vague reluctance and to think so dangerous about topical steroids. In conclusion, Korean people in community use topical agents well but still some exposed to risk from topical agents.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03a
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• pp.16-16
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• 2010

GaN-based light-emitting diodes (LEDs) are attracting great interest as candidates for next-generation solid-state lighting, because of their long lifetime, small size, high efficacy, and low energy consumption. However, for general illumination applications, the external quantum efficiency of LEDs, determined by the internal quantum efficiency (IQE) and the light extraction efficiency, must be further increased. The IQE is determined by crystal quality and epitaxial layer structure and high value of IQE more than 70% for blue LEDs have been already reported. However, there is much room for improvement of light extraction efficiency because most of the generated photons from active layer remain inside LEDs by total internal reflection at the interface of semiconductor with air due to the high refractive index difference between LEDs epilayer (for GaN, n=2.5) and air (n=1). The light confining in LEDs will be reabsorbed by the metal electrode or active layer, reducing the efficacy of LEDs. Here, we present the first demonstration of enhanced light extraction by forming a MgO nano-pyramids structure on the surface of vertical-LEDs. The MgO nano-pyramids structure was successfully fabricated at room temperature using conventional electron-beam evaporation without any additional process. The nano-sized pyramids of MgO are formed on the surface during growth due to anisotropic characteristics between (111) and (200) plane of MgO. The ZnO layer with quarter-wavelength in thickness is inserted between GaN and MgO layers to increase the critical angle for total internal reflection, because the refractive index of ZnO (n=1.94) could be matched between GaN (n=2.5) and MgO (n=1.73). The MgO nano-pyramids structure and ZnO refractive-index modulation layer enhanced the light extraction efficiency ofV-LEDs with by 49%, comparing with the V-LEDs with a flat n-GaN surface. The angular-dependent emission intensity shows the enhanced light extraction through the side walls of V-LEDs as well as through the top surface of the n-GaN, because of the increase in critical angle for total internal reflection as well as light scattering at the MgO nano-pyramids surface.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.67-72
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• 2018

Green tea (Camellia sinensis L.) has been widely explored for its medicinal applications. However, most of the studies had targeted the green tea leaf, while other parts remained unexplored. In this study, protective effect of green tea root extract on Normal Human Epidermal Keratinocytes (NHEKs) against the damage induced by an external stimulant (PM2.5) was confirmed. Thirty-year-old green tea root samples were collected from Amorepacific's Dolsongi tea field and green tea root extract was prepared with 70% ethanol. Total crude saponin content in green tea root extract was 54%, which is much higher than that in ginseng extract. Our results suggest that green tea root extract can be used as a natural surfactant in cosmetics. For evaluating its protective effect against the damage induced by PM2.5, IL-36G was used as a biomarker. IL-36G mRNA expression level increased remarkable upon PM2.5 treatment in NHEKs. Moreover, IL-36G was recently reported to be expressed in psoriasis lesions. Results showed significant decrease of IL-36G expression by treatment of green tea root extract. In conclusion, thirty-year-old green tea root extract can be used as a natural surfactant with a high saponin content and may have protective effect against the damage induced by PM2.5.