• Proceedings of the KSME Conference
• /
• 2004.11a
• /
• pp.1454-1459
• /
• 2004

The major parameters governing the fluid dynamical and thermo-dynamical behavior in the large pipeline network system are friction loss and the pipeline length. But in local pipeline networks and relatively short distance pipeline system, secondary loss and the considerations of the moving states of the fluid machine are also important. One of the major element in local pressure control system is pressure regulator. It causes the variations of the physical properties in that pipeline system. When it is under working, the accurate analysis of the flow properties is so difficult. In this study, some numerical approaches to investigate the critical-flow-characteristics of the pressure regulator have been done according to the variations of the opening ratio or cross-sectional area and the detail examinations and considerations of the pressure regulator as a pipeline network elements have been carried. Finally the flow-flied distributions and critical-flow-characteristics have been presented in detail and the critical flow phenomena and the relation to the opening ratio or cross-sectional-area ratio have been studied.

• Journal of Environmental Impact Assessment
• /
• v.21 no.3
• /
• pp.381-389
• /
• 2012

This study was conducted to analyze the weight factors for siting the electric facilities using Analytic Heirarchy Process technique participating the stakeholders. Siting the electric facilities has been a dispute of long standing because of landscape damage, geological deformation and various environmental problems such as electromagnetic effect to human health. For analyzing the weight factors by AHP technique, the questionnaire process was applied to the fifteen committee members including representatives of resident, academic experts, members of local assembly, officers of local government, journalists, etc. in Gangwondo, Korea. Weight factors for siting the electric facilities by AHP committee members resulted in residential areas 35.06%, cultural assets 16.68%, landscape conservation 13.11%, large-scale ecological corridor 10.17%, connectability of electric transmission line 8.32% respectively. The distance from residential areas was the most important factor preferred by committee members for siting the electric facilities.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.10 no.1
• /
• pp.115-122
• /
• 1983

The author surveyed 2,082 schoolchildren (Male: 1,078, Female: 1,004) from 7 to 12 years old in "N" primary school in kwang Ju City, and studied on 304 schoolchildren (Male: 176, Female: 128) having maxillary median diastema. The results were as follows: 1. The prevalence of maxillary median diastema was 14.6%, and it showed the greater rate at the boys than at the girls and the highest rate at 8 years old in the both sexes. 2. The maxillary median diastema showed decreasing tendency with ageing. 3. The frenum distance in children without local factors showed no change and the divergent degree of maxillary median diastema showed decreasing tendency after the eruption of maxillary lateral incisors. 4. The rate of maxillary median diastema associated with local factors was 37.8% and it showed increasing tendency with ageing. 5. The prevalence of median diastema according to etiology was as follows; rotated tooth; 12.2%, supernumerary teeth; 10.9%, abnormal frenum; 9.5%, peg lateralis; 7.2%, open bite; 2.6%, abnormal pattern of interseptal alveolar bone; 2.6%, missing lateral incisor; 0.7%, tooth size discrepancy; 0.3%.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
• /
• v.2 no.1
• /
• pp.49-56
• /
• 1998

This study identified the fumes produced from the cooking of the seasoned meats containing various condiments such as garlic, onion, pepper, soy sauce, and sesame oil. Concentrations, at the breathing zone of the cook, of volatile organic compounds (VOCs) and aldehydes included in the cooking fumes of seasoned meats were identified. Many chloro and fluoro-aliphatic hydrocarbons, aromatic hydrocarbons, ketones, and aldehydes, which could be carcinogen suspecting chemicals, were producing from the cooking fumes of the seasoned meats. This study also identified the ventilation efficiencies of the cooking fumes of the six exhaust ventilation systems, which were widely being used in the general apartments, houses, and small-food factories. For a comparison of the ventilation efficiencies of the systems, acetaldehyde was chosen as a marker pollutant and its concentrations at the breathing zone of the cook were identified. The laboratory fume hood showed the best ventilation efficiency of the six ventilation systems studied, and then the lateral hood ventilation and the down draft ventilation followed the laboratory fume hood. Finally, this study identified that both a wall factor nearby pollutant sources and a distance factor between the hood face and pollutant sources should be also considered for an effective local exhaust ventilation system design.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.7
• /
• pp.1439-1446
• /
• 2011

This paper describes the algorithm that lowers the dimension, maintains the object recognition and significantly reduces the eigenspace configuration time by combining the higher correlation feature information and Principle Component Analysis. Since the suggested method doesn't require a lot of computation than the method using existing geometric information or stereo image, the fact that it is very suitable for building the real-time system has been proved through the experiment. In addition, since the existing point to point method which is a simple distance calculation has many errors, in this paper to improve recognition rate the recognition error could be reduced by using several successive input images as a unit of recognition with K-Nearest Neighbor which is the improved Class to Class method.

• Journal of Korean Society for Atmospheric Environment
• /
• v.16 no.4
• /
• pp.327-338
• /
• 2000

complexity in atmospheric environment coupled with shoreline and complex terrain often causes local variations of meteorology that are distinct from those representative over larger surrounding area, These kinds of local variations are less significant in usual long-term environmental impact analyses dealing with continuous plume. The variations could however be crucial in predicting dispersion of toxic substance released in a relatively small area for a short duration. In the present paper the effects of spatial and temporal resolution of diagnostic wind field on the dispersion of the released substance are investigated by using a puff model. A hypothetical release scenario assumes that a substance is released from a location in the Yochon Industrial Estate and passively dispersed within a few-kilometer distance for an hour. The results show that diagnostic analysis could resolve more spatial variations to some extent by employing smaller grid size. The peak concentrations and puff trajectories obtained from spatially -and/or tmeporally -varing diagnostic wind field are found appreciably different from those obtained from uniform wind field. Attention to high-resolution wind field in the both spatial and temporal spaces is called in the consequence analysis of toxic substance release.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.11
• /
• pp.5692-5716
• /
• 2019

One of the best means to safeguard the confidentiality, security, and privacy of an image within the IoT-Cloud is through encryption. However, looking through encrypted data is a difficult process. Several techniques for searching encrypted data have been devised, but certain security solutions may not be used in IoT-Cloud because such solutions are not lightweight. We propose a lightweight scheme that can perform a content-based search of encrypted images, namely EEIRI. In this scheme, the images are represented using local features. We develop and validate a secure scheme for measuring the Euclidean distance between two descriptor sets. To improve the search efficiency, we employ the k-means clustering technique to construct a searchable tree-based index. Our index construction process ensures the privacy of the stored data and search requests. When compared with more familiar techniques of searching images over plaintexts, EEIRI is considered to be more efficient, demonstrating a higher search cost of 7% and a decrease in search accuracy of 1.7%. Numerous empirical investigations are carried out in relation to real image collections so as to evidence our work.

• Earthquakes and Structures
• /
• v.9 no.1
• /
• pp.93-109
• /
• 2015

Based on the reconnaissance of buildings in Dujiangyan City during 2008 Wenchuan earthquake, China, structural damage characteristics and the spatial distribution of structural damage are investigated, and the possible reasons for the extraordinary features are discussed with consideration of the influence of urban historical evolution and spatial variation of earthquake motions. Firstly, the urban plan and typical characteristics of structural seismic damage are briefly presented and summarized. Spatial distribution of structural damage is then comparatively analyzed by classifying all surveyed buildings in accordance with different construction age, considering the influence of seismic design code on urban buildings. Finally, the influences of evolution of seismic design code, topographic condition, local site and distance from fault rupture on spatial distribution of structural damage are comprehensively discussed. It is concluded that spatial variation of earthquake motions, resulting from topography, local site effect and fault rupture, are very important factor leading to the extraordinary spatial distribution of building damage except the evolution of seismic design codes. It is necessary that the spatial distribution of earthquake motions should be considered in seismic design of structures located in complicated topography area and near active faults.

• Journal of Korean Society for Atmospheric Environment
• /
• v.21 no.E3
• /
• pp.107-113
• /
• 2005

Using a sampling device of our own making, airborne pollen has been monitored in Kyoto, Japan from the middle of February to the end of May 2004. From the morphological analysis of pollen grains by Scanning Electron Microscope (SEM), it was possible to identify some pollen types like Cryptomeria, Pine, Alder, Cyclobalanopsis, Chamaecyparis, and Equisetum. Daily average airborne pollen counts show strong variations from the day to day which makes the appropriate daily forecasts that could be of practical use for patients difficult. Diurnal variation of airborne pollen grains at our local sampling site is very irregular and shows no similarity between pollen types. The highest concentrations of Cryptomeria and Alder pollens in the south -west wind directions might be attributed to the airborne pollen transport, while the increase in Pine pollen grain in the southern wind direction was probably due to the local spread. Prevailing wind direction (SW) during the pollinating periods of Cryptomeria and Alder pollens could suggest a long-distance transport from a distant mountain.

• Journal of Korean Neurosurgical Society
• /
• v.38 no.4
• /
• pp.293-298
• /
• 2005

Objective : The authors investigate the spatial characteristics of apoptotic genes expressed around the focal cerebral infarction, and attempted to explain the penumbra with them. Methods : A delayed focal cerebral infarction was created in twelve adult Sprague-Dawley rats. We performed the immunohistochemical staining for the apoptosis, bcl-2 and p53 proteins and measured the local cerebral blood flow [CBF] at the infarction core area and peri-infarct area pre- and intra-operatively. The peri-infarct area was divided into six sectors by distance from the infarction border. Results : The size [$mm^2$] of apoptosis, bcl-2, and p53 areas were $3.1{\pm}1.2$, $4.7{\pm}2.1$, and $6.8{\pm}2.4$, respectively. Apoptosis, bcl-2 or p53 positive cells were concentrated at the peri-infarct area adjacent to the infarction core. Their numbers reduced peripherally, which was inversely proportional to the local CBF. The p53 area seems to overlap with and larger than the ischemic penumbra. Conclusion : The p53 positive area provides a substitutive method defining the penumbra under the molecular base of knowledge.