• Journal of Mechanical Science and Technology
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• v.16 no.8
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• pp.1144-1153
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• 2002

A hybrid performance prediction method is proposed in the present study. A channel diffuser is divided into four subregions: vaneless space, semi-vaneless space, channel, and channel exit region. One-dimensional compressible core flow and boundary layer calculation of each region with an incidence loss model and empirical correlation of residuary pressure recovery coefficient of a channel predict the performance of diffusers. Three channel diffusers are designed and tested for validating the developed prediction method. The pressure distributions from an impeller exit to the channel diffuser exit are measured and discussed for various operating conditions from choke to nearly surge conditions. The strong non-uniform pressure distribution which is caused by impeller-diffuser interaction is obtained over the vaneless and semi-vaneless spaces. The predicted performance shows good agreement with the measured performance of diffusers at a design condition as well as at off-design conditions.

• Journal of Information Technology Applications and Management
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• v.15 no.2
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• pp.67-82
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• 2008

Risk that breed large size disaster is happening variously for cause at social. natural a management. Incidence and damage scale are trend that increase rapidly than past. In these circumstance, to keep operational continuity of organization, area, society, risk management action that establish systematic counter measure estimating and analyze occurrence possibility and expectation damage of risk is essential indispensable issue and the best countermeasure. Risk management action does by main purpose establish optimum disaster reduction countermeasure. To deduce various countermeasure, process that estimate and analyze occurrence possibility and expectation damage of risk is essential indispensable issue. Therefore, this paper studies process design that can presume risk occurrence frequency and damage scale through distribution of probability.

• Communications for Statistical Applications and Methods
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• v.24 no.3
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• pp.271-290
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• 2017

We study a bivariate response regression model with arbitrary marginal distributions and joint distributions using Frank and Clayton's families of copulas. The proposed model is used for fitting dependent bivariate data with explanatory variables using the log-odd log-logistic Weibull distribution. We consider likelihood inferential procedures based on constrained parameters. For different parameter settings and sample sizes, various simulation studies are performed and compared to the performance of the bivariate odd-log-logistic-Weibull regression model. Sensitivity analysis methods (such as local and total influence) are investigated under three perturbation schemes. The methodology is illustrated in a study to assess changes on schoolchildren's oral health-related quality of life (OHRQoL) in a follow-up exam after three years and to evaluate the impact of caries incidence on the OHRQoL of adolescents.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2071-2077
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• 2013

Esophageal cancer is a mjaor health problems in many parts of the world. A geographical information system (GIS) allows investigation of the geographical distribution of diseases. The purpose of the present study was to explore the relationship between esophageal cancer and effective climatic factors using GIS. The dispersion distribution and the relationship between environmental factors effective on cancer were measured using Arc GIS. The highest degree of spread was in Germi town and the least was in Ardabil city. There was a significant relationship between effective environmental factors and esophageal cancer in Ardabil province. The results indicated that environmental factors probably are influential in determining the incidence of esophageal cancer. Also, these results can be considered as a window to future comprehensive research on esophageal cancer and related risk factors.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.4
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• pp.507-513
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• 2001

Time averaged pressure distributions in a high-speed centrifugal compressor channel diffuser at design and off-design flow rates are investigated. Pressure distributions from the impeller exit to the channel diffuser exit are measured for various flow rates from choke to near surge condition, and the effects of operating condition are discussed. The strong non-uniformity in the pressure distribution is obtained over the vaneless space and semi-vaneless space caused by the impeller-diffuser interaction. As the flow rate increases, flow separation near the throat, due to large incidence angle at the vane leading edge, increases aerodynamic blockage and reduces the aerodynamic flow area downstream. Thus the minimum pressure location occurs downstream of the geometric throat, and it is named as the aerodynamic throat. And at choke condition, normal shock occurs downstream of this aerodynamic throat. The variation in the location of the aerodynamic throat is discussed.

• Korean Journal of Head & Neck Oncology
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• v.15 no.1
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• pp.9-17
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• 1999

Objectives: The records of 936 patients with previously untreated carcinoma of the head and neck were reviewed in order to define the incidence and topographical distribution of neck node metastasis on admission. Materials and Methods: The common regions of metastasis are presented for each of the 12th individual head and neck sites selected for study. Results and Conclusion: Knowledge of the preferred areas of spread and those that are almost never involved allows the design of more adequate radiation therapy plans to manage the individual tumors.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.4
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• pp.241-250
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• 1986

Current distributions are the basis of analyzing and designing the antenna. In this paper, a method of deriving the current distribution of a spiral shaped thin wire scattere is proposed when plane wave is incident on it. The calculated results are also shown for severla spiral sizes and incidence angles selected. For numerical calculation, the method of point matching is used with a cubic B-spline function as a basis function.

• Korean Journal of Veterinary Research
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• v.11 no.1
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• pp.55-58
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• 1971

At the Seoul first slaughter house, 2,964 heads of swine were examined for the infection and distribution of Cysticercus tenuicollis. The results were summarized as follows. 1. The Cysticercus tenuicollis were detected from 106 heads of swine and the infection rate were 3.58 percent. 2. Incidence at each province were 5.7% in Jeon-ra-puk Do, 4.4% in Chung-cheong-nam Do, 3.83% in Kyong-sang-nam Do, 3.57% in Jeon-ra-nam Do, 2.52% in Kang-won Do, 1.75% in Kyong-sang-puk Do, and Kyong-gi Do and Seoul City were not recognized. 3. The monthly variation of the infection of Cysticercus tenuicollis were not found nearly through a year. 4. The usual habitat of Cysticercus tenuicollis were recognized the omentum and liver, but unusually one case was found around the rectum.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.22 no.2
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• pp.259-269
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• 1992

The author has examined the abnormalities in panoramic radiographs of 668 edentulous patients. The distribution, type, incidence, and location of all abnormalities were analized, and the distances between alveolar crest and anatomical structures were measures. (Maxillary measurements were performed between alveolar crest and lower margin of the maxillary sinus and mandibular measurements between alveolar crest and upper edge of the mental foramen.) The obtained results were as follows: 1. Of the 668 panoramic radiographs examined, 103(15.4%) showed one or more abnormalities. 2. The incidence of abnormalities was decreased by years, which was 22.0% in 1970's and 16.8% in 1980's and 12.1 % in 1990's. 3. The distribution of abnormalities as follows; 43 (40.2%) superficial root fragments, 24(22.4%) impacted teeth, 9(8.4%) imbedded root fragments, 7 (6.5%) cysts, 7(6.5%) fractures, 5(4.7%) foreign bodies, 5(4.7%) abnormal radiolucencies, 4(3.7%) abnormal radiopacities, 2(1.9%) bony defects, 1(0.9%) tumor. 4. In the location of abnormalities, 42 cases (35.3%) were in the maxillary posterior region, 26 cases(21.8%) were in the maxillary anterior region, 20 cases(24.4%) were in the mandibular posterior region and 18 cases(15.1%) were in the mandibular anterior region. 5. In the distance between alveolar crest and maxillary sinus, 109 cases(9.7%) were below 0.5㎜, 757 cases(67.6%) were between 0.5㎜ and 10㎜, 254 cases(22.7%) were above 10㎜. In the distance between alveolar crest and mental foramen, 73 cases (8.8%) were below 0.5㎜, 501 cases (60.7%) were between 0.5㎜ and l0㎜ and 252 cases(30.5%) were above 100㎜.

• Wind and Structures
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• v.24 no.2
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• pp.95-118
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• 2017

The present study revealed comparison the pressure distribution on the surfaces of regular cross plan shaped building with angular cross plan shaped building which is being transformed from basic cross plan shaped building through the variation of internal angles between limbs by $15^{\circ}$ for various wind incidence angle from $0^{\circ}$ to $180^{\circ}$ at an interval of $30^{\circ}$. In order to maintain the area same the limbs sizes are slightly increased accordingly. Numerical analysis has been carried out to generate similar nature of flow condition as per IS: 875 (Part -III):1987 (a mean wind velocity of 10 m/s) by using computational fluid dynamics (CFD) with help of ANSYS CFX ($k-{\varepsilon}$ model). The variation of mean pressure coefficients, pressure distribution over the surface, flow pattern and force coefficient are evaluated for each cases and represented graphically to understand extent of nonconformities due to such angular modifications in plan. Finally regular cross shaped building results are compared with wind tunnel results obtained from similar '+' shaped building study with similar flow condition. Reduction in along wind force coefficients for angular crossed shaped building, observed for various skew angles leads to develop lesser along wind force on building compared to regular crossed shaped building and square plan shaped building. Interference effect within the internal faces are observed in particular faces of building for both cases, considerably. Significant deviation is noticed in wind induced responses for angular cross building compared to regular cross shaped building for different direction wind flow.