• Korean Journal of Agricultural and Forest Meteorology
• /
• v.11 no.4
• /
• pp.192-205
• /
• 2009

The unexpected wind over the Mt. Hwawang on 9 February 2009 was deadly when many spectators were watching a traditional event to burn dried grasses and the fire went out of control due to the wind. We analyzed the fatal wind based on wind flow simulations over a digitized complex terrain of the mountain with a localized heating area using a three dimensional computational fluid dynamics model, CFD_NIMR_SNU (Computational Fluid Dynamics_National Institute of Meteorological Research_Seoul National University). Three levels of fire intensity were simulated: no fire, $300^{\circ}C$ and $600^{\circ}C$ of surface temperature at the site on fire. The surface heat accelerated vertical wind speed by as much as $0.7\;m\;s^{-1}$ (for $300^{\circ}C$) and $1.1\;m\;s^{-1}$ (for $600^{\circ}C$) at the center of the fire. Turbulent kinetic energy was increased by the heat itself and by the increased mechanical force, which in turn was generated by the thermal convection. The heating together with the complex terrain and strong boundary wind induced the unexpected high wind conditions with turbulence at the mountain. The CFD_NIMR_SNU model provided valuable analysis data to understand the consequences of the fatal mountain fire. It is suggested that the place of fire was calm at the time of the fire setting due to the elevated terrain of the windward side. The suppression of wind was easily reversed when there was fire, which caused updraft of hot air by the fire and the strong boundary wind. The strong boundary wind in conjunction with the fire event caused the strong turbulence, resulting in many fire casualties. The model can be utilized in turbulence forecasting over a small area due to surface fire in conjunction with a mesoscale weather model to help fire prevention at the field.

• Journal of Intelligence and Information Systems
• /
• v.16 no.3
• /
• pp.181-199
• /
• 2010

As rapid progress of population aging and strong interest in health, the demand for new healthcare service is increasing. Until now healthcare service has provided post treatment by face-to-face manner. But according to related researches, proactive treatment is resulted to be more effective for preventing diseases. Particularly, the existing healthcare services have limitations in preventing and managing metabolic syndrome such a lifestyle disease, because the cause of metabolic syndrome is related to life habit. As the advent of ubiquitous technology, patients with the metabolic syndrome can improve life habit such as poor eating habits and physical inactivity without the constraints of time and space through u-healthcare service. Therefore, lots of researches for u-healthcare service focus on providing the personalized healthcare service for preventing and managing metabolic syndrome. For example, Kim et al.(2010) have proposed a healthcare model for providing the customized calories and rates of nutrition factors by analyzing the user's preference in foods. Lee et al.(2010) have suggested the customized diet recommendation service considering the basic information, vital signs, family history of diseases and food preferences to prevent and manage coronary heart disease. And, Kim and Han(2004) have demonstrated that the web-based nutrition counseling has effects on food intake and lipids of patients with hyperlipidemia. However, the existing researches for u-healthcare service focus on providing the predefined one-way u-healthcare service. Thus, users have a tendency to easily lose interest in improving life habit. To solve such a problem of u-healthcare service, this research suggests a u-healthcare recommender system which is based on collaborative filtering principle and social network. This research follows the principle of collaborative filtering, but preserves local networks (consisting of small group of similar neighbors) for target users to recommend context aware healthcare services. Our research is consisted of the following five steps. In the first step, user profile is created using the usage history data for improvement in life habit. And then, a set of users known as neighbors is formed by the degree of similarity between the users, which is calculated by Pearson correlation coefficient. In the second step, the target user obtains service information from his/her neighbors. In the third step, recommendation list of top-N service is generated for the target user. Making the list, we use the multi-filtering based on user's psychological context information and body mass index (BMI) information for the detailed recommendation. In the fourth step, the personal information, which is the history of the usage service, is updated when the target user uses the recommended service. In the final step, a social network is reformed to continually provide qualified recommendation. For example, the neighbors may be excluded from the social network if the target user doesn't like the recommendation list received from them. That is, this step updates each user's neighbors locally, so maintains the updated local neighbors always to give context aware recommendation in real time. The characteristics of our research as follows. First, we develop the u-healthcare recommender system for improving life habit such as poor eating habits and physical inactivity. Second, the proposed recommender system uses autonomous collaboration, which enables users to prevent dropping and not to lose user's interest in improving life habit. Third, the reformation of the social network is automated to maintain the quality of recommendation. Finally, this research has implemented a mobile prototype system using JAVA and Microsoft Access2007 to recommend the prescribed foods and exercises for chronic disease prevention, which are provided by A university medical center. This research intends to prevent diseases such as chronic illnesses and to improve user's lifestyle through providing context aware and personalized food and exercise services with the help of similar users'experience and knowledge. We expect that the user of this system can improve their life habit with the help of handheld mobile smart phone, because it uses autonomous collaboration to arouse interest in healthcare.

• Journal of radiological science and technology
• /
• v.29 no.2
• /
• pp.83-92
• /
• 2006

Based on the data of cervical cancer patients who were treated by the radiotherapy with concurrent chemotherapy at the radiation oncology department of National Cancer Center from January 2002 to February 2003, we have studied the method recommended by ICRU 38 to maximize the prescription dose to the planing target volume (PTV) with minimizing the dose to surrounding normal organs. Clinical stage of the patients are 1 patient for stage IB, 3 patients for IIA, 19 patients for IIB, 3 patients for IIIA, 3 patients for IIIB and 1 patient for IV. All patients took the MRI before treatment and the maximum size of the gross tumor volume were under 4cm for 17 patients and from 4 cm to 6 cm for 12 patients and above 6 cm for 1 patient. The results show that while the irradiated volume can be reduced with optimized dose distribution using PTV treatment planning (p<0.0001) when the remained tumor size is small, the surrounding normal organs will receive unnecessarily large dose when the irradiated tumor volume is relatively large. This is because there is some limitation in controling the intensity of radiation in Fletcher Williamson Applicator. To overcome the limit of applicator and to achieve the optimal dose distribution, we have virtually applied 4 needles with Fletcher Williamson Applicator for 10 patients who have relatively large tumor and studied the change in dose distribution before and after application. The results show that this new virtual treatment plan reduces the volume covered by 100 % isodose (p=0.0608, p=0.0607) and reduces the dose of normal organs (p=0.0162, p=0.008). This evidence suggest that this method is superior than the currently used method such as PTV treatment and ICRU treatment.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.9 no.1
• /
• pp.39-47
• /
• 2006

Purpose: We proposed a new classification of pediatric intussusception based on clinical and radiologic findings. Methods: Data from 88 consecutive patients with intussusception were reviewed. We retrospectively analyzed six factors; patient age, sites of intussusception, symptoms, therapeutic methods, existence of enlarged mesenteric lymph nodes, and ultrasonographic (US) findings from clinical records. Results: 1) There was one neonatal case (1.1%), the others (98.9%) were infants and children. 2) These 87 infant and child cases consisted of 14 cases (16.1%) of small bowel intussusception (SBI) and 73 cases (83.9%) of ileo-colic intussusception (ICI). Of the 14 SBI cases, 12 cases were symptomatic and 2 cases were asymptomatic. The symptomatic group comprised 8 transient cases (66.7%), 3 operative cases (25.0%), and 1 enema-reduction case (8.3%). Two asymptomatic cases were incidentally captured by computed tomography. Of the 73 ICI cases, 19 cases (26.0%) required operation, and 54 (74.0%) enema-reduction. 3) When transient SBI cases were compared with operated SBI cases, enema-reduced and operated ICI cases, the age ($38.0{\pm}22.9$ months) of transient SBI cases were significantly higher than those of the others (p=0.003). Mean mass size ($20.8{\pm}2.7mm$) in transient SBI was significantly smaller than in the others (p=0.0001). 4) No correlation was found between the existence of enlarged mesenteric lymph nodes and therapeutic method or concomitant illness. 5) Most of the target types observed by US were in transient SBI cases, the remainder were in the enema-reduced ICI cases. In terms of the doughnuts type, all 8 cases (34.8%) with an external hypoechoic rim thickness of >8.9mm were treated surgically. Conclusion: Pediatric intussusception may be classified based on clinical and radiologic findings, which are likely to indicate appropriate therapies.

• Asia pacific journal of information systems
• /
• v.23 no.2
• /
• pp.21-39
• /
• 2013

As the utilization of information technology and the turbulence of technological change increase in organizations, the adoption of IT outsourcing also grows to manage IT resource more effectively and efficiently. In this new way of IT management technique, service level management(SLM) process becomes critical to derive success from the outsourcing in the view of end users in organization. Even though much of the research on service level management or agreement have been done during last decades, the performance of the service level management process have not been evaluated in terms of final objectives of the management efforts or success from the view of end-users. This study explores the relationship between SLM maturity and IT outsourcing success from the users' point of view by a analytical case study in four client organizations under an IT outsourcing vendor, which is a member company of a major Korean conglomerate. For setting up a model for the analysis, previous researches on service level management process maturity and information systems success are reviewed. In particular, information systems success from users' point of view are reviewed based the DeLone and McLean's study, which is argued and accepted as a comprehensively tested model of information systems success currently. The model proposed in this study argues that SLM process maturity influences information systems success, which is evaluated in terms of information quality, systems quality, service quality, and net effect proposed by DeLone and McLean. SLM process maturity can be measured in planning process, implementation process and operation and evaluation process. Instruments for measuring the factors in the proposed constructs of information systems success and SL management process maturity were collected from previous researches and evaluated for securing reliability and validity, utilizing appropriate statistical methods and pilot tests before exploring the case study. Four cases from four different companies under one vendor company were utilized for the analysis. All of the cases had been contracted in SLA(Service Level Agreement) and had implemented ITIL(IT Infrastructure Library), Six Sigma and BSC(Balanced Scored Card) methods since last several years, which means that all the client organizations pursued concerted efforts to acquire quality services from IT outsourcing from the organization and users' point of view. For comparing the differences among the four organizations in IT out-sourcing sucess, T-test and non-parametric analysis have been applied on the data set collected from the organization using survey instruments. The process maturities of planning and implementation phases of SLM are found not to influence on any dimensions of information systems success from users' point of view. It was found that the SLM maturity in the phase of operations and evaluation could influence systems quality only from users' view. This result seems to be quite against the arguments in IT outsourcing practices in the fields, which emphasize usually the importance of planning and implementation processes upfront in IT outsourcing projects. According to after-the-fact observation by an expert in an organization participating in the study, their needs and motivations for outsourcing contracts had been quite familiar already to the vendors as long-term partners under a same conglomerate, so that the maturity in the phases of planning and implementation seems not to be differentiating factors for the success of IT outsourcing. This study will be the foundation for the future research in the area of IT outsourcing management and success, in particular in the service level management. And also, it could guide managers in practice in IT outsourcing management to focus on service level management process in operation and evaluation stage especially for long-term outsourcing contracts under very unique context like Korean IT outsourcing projects. This study has some limitations in generalization because the sample size is small and the context itself is confined in an unique environment. For future exploration, survey based research could be designed and implemented.

• 한국해양학회지
• /
• v.27 no.3
• /
• pp.250-258
• /
• 1992

The oxygen isotope composition of surface waters in the Bransfield Strait was determined as one extra state variable in order to characterize water masses in the region, since salinity is significantly modified due to the freezing and ice-melting in the polar region. The salinity, temperature, and $\delta$/SUP 18/O values vary from 34.0 to 34.5$\textperthousand$, -.05 to 2.1$^{\circ}C$ and -0.50 t -0.26$\textperthousand$, respectively. The combined effects of evaporation, precipitation, freezing, ice-melting are reflected in the widely scattered data. Although it is small, the distribution of $\delta$/SUP 18/O of the Bransfield Strait is strongly affected by the freezing-ice melting rather than the evaporation-precipitation. The ice melted fresh water which has higher temperature, depleted salinity and nutrients may be injected to the Bransfield Strait from the north. The concentrations of nutrients are decreasing gradually from the north to the south. The waters were characterized by two groups of higher (about 19.4) and lower N/P ratio (about 16.7). The lower N/P ratio is found in the northern part where ice-melted fresh water is injected. and the higher N/P ratio is found in the southern part of the Bransfield Strait. Although more precise work is needed, the deference of N/P ratio can be an evidence of the ice melted water injection to the Bransfield Strait. Chlorophyll a concentrations, in general, increase from northwest (Waddell Sea) to the southeast (Smith and Hosseason Islands). Probably the injection of nutrient depleted fresh water from the ice melting reduce the chlorophyll a concentration.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.8 no.4
• /
• pp.357-368
• /
• 2003

Time-series CTDT (Conductivity/Temperature/Depth/Transmissivity) were obtained at one point near tidewater glacier of Marian Cove (King George Islands, Antarctica) to present water column properties and SPM (suspended particulate matter) dispersal pattern in relation with tide, current, meteorological data, and SPM concentration. Four layers were divided from the water column characteristics measured in the interval of an hour for about 2 days: 1) cold, fresh, and turbid surface mixed layer between 0-20 m in water depth, 2) warm, saline, and relatively clean Maxwell Bay inflow between 20-40 m in water depth, 3) turbid/cold tongue of subglacial discharges compared with the ambient waters between 40-70 m in water depth, and 4) cold, saline, and clean bottom water beneath 70 m in water depth. Surface plume, turbid freshwater at coastal/cliff area in late summer (early February), had the characteristic temperature and SPM concentration according to morphology, glacial condition, and composition of sediments. The restrict dispersion only over the input source of meltwater discharges was due to calm wether condition. Due to strong wind-induced surface turbulence, fresh and turbid surface plume, englacial upwelling cold water, glacier-contact meltwater, and Maxwell Bay inflow was mixing at ice-proximal zone and the consequent mixed layer deepened at the surface. Large amount of precipitation, the major controlling factor for increasing short-term glacial discharges, was accompanied by the apparent development of subglacial discharge that resulted in the rapid drop of salinity below the mid depth. Although amount of subglacial discharge and englacial upwelling may be large, however, their low SPM concentration would have small influence on bottom deposition of terrigenous sediments.

• Korean Journal of Ecology and Environment
• /
• v.36 no.2 s.103
• /
• pp.124-138
• /
• 2003

This paper aimed to analyze the relationship between alga3 bloom patterns and hydrological, limnological data which were collected from major reservoirs in Korea for 8 years (1990${\sim}$1997). Water temperature of river-type reservoirs showed wider seasonal fluctuations than that of lake-type. pH of lake-type reservoirs was low in winter season but high in summer season. In contrast, river-type reservoirs showed high pH in spring and autumn seasons as well, and very low in summer season. COD of lake-type reservoirs and Paldang reservoir was lower (2${\sim}$3 mg/L) than that of Geumgang and Nagdonggang reservoirs (6${\sim}$9 mg/L). Dissolved oxygen (DO) of river-type reservoirs was higher than that of lake-type reservoirs. Seasonal fluctuation pattern of DO saturation in river-type reservoirs was high (80 ${\sim}$100%) and remained relatively constant whereas lake-type reservoirs showed the highest level (93%) in late spring or early summer, which gradually decreased entering winter season(46${\sim}$06%). And monthly variation of DO saturation showed inverse proportion to water volume in lake-type reservoirs. Nutrients concentration in river-type lake is higher than lake-type. Seasonal fluctuation of nutrients (T-N, T-P) in lake-type reservoirs was relatively small than that of river-type reservoirs. Annual mean N/P mass ratio of lake-type reservoirs was higher than that of river-type. Transparency tended to related with the suspended solid concentration in river-type reservoirs. Algal bloom of lake-type and river-type reservoirs occurred at any time except rainfall and winter periods. And it dominated in summer and early autumn, respectively. Algal bloom of river-type reservoirs was higher than that of lake-type. Relationship between rainfall and chlorophyll- a in lake-type reservoirs was relatively high, however river-type reservoirs showed insignificant.

• Korean Journal of Food Science and Technology
• /
• v.33 no.5
• /
• pp.567-573
• /
• 2001

Lactobacilli have been generally recognized as an important lactic acid bacteria present in the normal human intestinal flora. Fifty two Lactobacillus isolates were recovered from the feces of healthy Koreans whose age ranged from thirteen days after birth to 37 years. Among the isolates above, 17 isolates were tentatively identified as strains of Lactobacillus acidophilus and 3 isolates as strains of Lactobacillus casei. For their characterization, these twenty isolates were subjected to the experiments for the resistance to the artificial gastric juice, pH2.5 and bile salt. Interestingly, 3 strains survived pH 2.5 after 3 hour incubation in the artificial gastric juice with more than 75% of survival rate. L. acidophilus a-4 had the highest survival rate of 100%. Four strains including L. acidophilus a-3 grew gradually in MRS broth in the presence of the artificial bile salt. Cholesterol assimilation was also tested for the 20 isolates. The result showed that cholesterol concentration of the medium was reduced by 10 Lactobacillus isolates with more than 60%, as compared to the control. L. acidophilus a-2 had the highest reduction rate of 77%. Judging from these data obtained in vitro, some isolates ware likely to reach the lower small intestine after consumption without a significant loss of viability, suggesting that they had the potential to be developed as a probiotic culture which might lower the cholesterol level in human.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.38 no.3
• /
• pp.11-24
• /
• 2020

The purpose of this study was to re-examine the neglected and forgotten Cheongdo Geoyeonjeong, to correct the wrong contents, examine the changes and conditions of the garden, and to establish basic data on the components of the forest in the future. In addition, it was extended to the Gongampungbyeog Cliff, the influence area of the Geoyeonjeongwonlim, and the results of the study were as follows; First, Based on the recitation of "Seonyu pungryu(仙遊風流)" in the "Cheongsuheon-yugo(聽水軒遺稿),", Dongchangcheon Stream and Gongampungbyeog(孔巖楓壁) were influenced by the outer gardens of the Georyeonjeongwonrim. Second, Small pavilion was built and arranged under the rock of Byeongam(Byeongpungbawi) in the management history of Geoyeonjeong Pavilion. The records show that Cheongsuheon used the Geoyeonjeong Pavilion as the original forest and even recognized Oewon, which is a scenic influence, as the Gongampungbyeog Cliff. Third, Many of the poems related to Gongam were recognized as Seunggyeong, which represents the Unmun area, and the eight scenery of Cheongdo and Unmungugok were established here as proof that Gongampungbyeog Cliff was very faithful to the traditional Seunggyeong aspect of Gongampungbyeog Cliff, and the crystalline structure of the location was implied as an external source of Geoyeonjeongwonlim. Fourth, The lower part of Dongchangcheon Stream, which stretches from Geoyeonjeongwonrim to Gongam, is filled with attractions consisting of cancerous areas such as Punghodae, Moseongam, Buangdae, Gokcheondae, Saganjeong, Hakgadae, and Hyeongjeam, which provide a clearer picture of the space and landscape of the Geyeonjeongwonrim Outer Garden. Fifth, The expression "dragging water, spilling it into the courtyard, and sending it back to the downtown of the field" of the Cheongsuheon-yugo suggests that the site of Geoyeonjeong Pavilion was originally a prevention. It is also inferred that Cheng Shu-heon also wanted to respect runners and pursue natural views like runners. Sixth, The record of planting a description of spring water and willow trees in "Geoyeonjeong Manyeong(居然亭晩影)」" and "Sanggukseol(霜菊說)」" suggests that the chrysanthemum was planted and planted, and that the chrysanthemum was used to describe the Osanggojeol(傲霜孤節), which means that he would not yield and keep his incision alone despite severe frost. Seventh, It is believed that the writing was written by Cheongsuheon in 1844 during the period of the creation of the Wonrim. The rock letters on the floor of Geoyeonjeong suggest the names of the receiving and the winning prizes. Most of the passages are based on nuclear power plants, including Muidogyo of the Zhuzi, and most of them incorporate the virtues of the Gunja and the natural views of the Eunja. In addition, the rock writing 'Gyeong(敬)' or 'Uidang(義堂)' is a substitute for special worship objects or introspection, adding to the significance and scenic properties of the Georyeon Garden Forest.