• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.12
• /
• pp.6391-6395
• /
• 2012

Background: Ovarian cancer is ranked as the fifth most common cause of cancer death in women. In Malaysia, it is the fourth most common cancer in females. CA125 has been the tumor marker of choice in ovarian cancer but its diagnostic specificity in early stages is only 50%. Hence, there is a critical need to identify an alternative tumor marker that is capable of detecting detect ovarian cancer at an early stage. HE4 is a new tumor marker proposed for the early diagnosis of ovarian cancer and disease recurrence. Currently, none of the normal ranges of HE4 quoted in the literature are based on data for a multiethnic Asian population. Therefore, the aim of this study was to determine reference intervals for HE4 in an Asian population presenting in University Malaya Medical Centre, a tertiary reference hospital. Materials and Methods: 300 healthy women were recruited comprising 150 premenopausal and 150 postmenopausal women, aged from 20-76 years. All women were subjected to a pelvic ultrasonograph and were confirmed to be free from ovarian pathology on recruitment. Serum HE4 levels were determined by chemiluminescent microparticle immunoassay (CMIA, Abbott Architect). The reference intervals were determined following CLSI guidelines (C28-A2) using a non-parametric method. Results: The upper limits of the $95^{th}$ percentile reference interval (90%CI) for all the women collectively were 64.6 pmol/L, and 58.4 pmol/L for premenopausal) and 69.0 pmol/L for postmenopausal. The concentration of HE4 was noted to increase with age especially in women who were more than 50 years old. We also noted that our proposed reference limit was lower compared to the level given by manufacturer Abbott Architect HE4 kit insert (58.4 vs 70 pmol/L for premenopausal group and 69.0 vs 140 pmol/L in the postmenopausal group). The study also showed a significant difference in HE4 concentrations between ethnic groups (Malays and Indians). The levels of HE4 in Indians appeared higher than in Malays (p<0.05), while no significant differences were noted between the Malays and Chinese ethnic groups. Conclusions: More data are needed to establish a reference interval that will better represent the multiethnic Malaysian population. Probably a larger sampling size of equal representation of the Malay, Chinese, Indians as well as the other native ethnic communities will give us a greater confidence on whether genetics plays a role in reference interval determination.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.6C
• /
• pp.203-212
• /
• 2011

This paper investigates the caharactheristics of the earth pressure magnigue and distribution in jointed rockmass for a safe and economic design and construction of earth retaining structures installed in rock stratum. For this purpose, this study will first investigate the limitations and problems of the existing earth pressure studies and then to overcome them th study will conduct the discontinuum numerical parametric studies based on the Discrete Element Method (DEM), which can consider the joint characteristics in rock stratum. The controlled parameters include rock type and joint conditions (joint shear strength and joint angle), and the magnitude and distribution characteristics of earth pressure have been investigated considering the interactions between the ground and the retaining structures. In addition, the comparison between the earth pressures induced in rock stratum and Peck's earth pressure for soil ground has been carried out. From the comparison, it is found that the earth pressure magnitude and distribution in jointed rockmass has been highly affected by rock type and joint condition and has shown different characteristics compared with the Peck's empirical earth pressure. This result would hereafter be utilized as an important information and a useful data for the assessment of earth pressure for designing a retaining structures installed in jointed rockmass.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.31 no.3
• /
• pp.23-30
• /
• 2003

In this study, the various load cases by specified by the IEC61400-1 international specification and GL Regulations for the wind energy conversion system were considered, and a specific composite structure configuration which can effectively endure various loads was proposed. In order to evaluate the structure, the structural analysis for the composite wind turbine blade was performed using the finite element method(FEM). In the structural design, the acceptable configuration of blade structure was determined through the parametric studies, and the most dominant design parameters were confirmed. In the stress analysis using the FEM, it was confirmed that the blade structure was safe and stable for all the considerd load cases. Moreover the safety of the blade root joint with insert bolts, newly devised in this study, was checked against the design loads and also the fatigue loads. The fatigue life for operating more than 20 years was estimated by using the well-known S-N linear damage rule, the load spectrum and Spera's empirical equations. The full-scale static test was performed under the simulated aerodynamic loads. from the experimental results, it was found that the designed blade had the structural integrity. Furthermore the measured results were agreed with the analytical results such as deflections, strains, the mass and the radial center of gravity. The studied blade was successfully certified by an international institute, GL, of Germany.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.27 no.2
• /
• pp.94-104
• /
• 2015

Population and urban development along the coast is growing in South Korea, and particularly sea level rise is likely to increase the vulnerability of coastal areas. This study aims to investigate the sea level rise through Mann-Kendall(MK) test, ordinary linear regression(OR) and quantile regression analysis(QRA) with sea level data at the 20 tide stations along the coast of Korean Peninsula. First, statistically significant long-term trends were analysed using a non-parametric MK test and the test indicated statistically significant trends for 18 and 10 stations at the 5% significance level in the annual mean value of sea level and the annual maximum value of sea level, respectively. The QRA method showed better performance in terms of characterizing the degree of trend. QRA showed that an average annual rise in mean sea level is about 1-6 mm/year, and an average rise in maximum sea level is about 1-20 mm. It was found that upward convergent and upward divergent were a representative change given the nine-category distributional changes. We expect that in future work we will address nonstationarities with respect to sea level that were identified above, and develop a nonstationary frequency analysis with climate change scenarios.

• Journal of Periodontal and Implant Science
• /
• v.36 no.3
• /
• pp.591-600
• /
• 2006

Purpose: This study assessed the impact of self-reported periodontal health on the oral health-related quality of life among elderly Koreans. Methods: Four hundred twenty one elderly Koreans in Seoul and suburban areas were selected with a cluster (institution) sampling method, and were requested to take oral examinations and finish questionnaires on the Oral Health Impact Profile-14(OHIP-14). and self-reported periodontal health status, such as periodontal symptoms, self-rated periodontal health and periodontal treatment need. As the dependent variable, OHIP-14 showed a positive skewed distribution (skewness: 1.17), we transformed to square-root form to apply parametric analyses. Bivariate analysis by t-test and ANOVA, and multivariate analysis with the two-level regression model accounting clusters were implemented. Results: Mean age of the subjects was 74.6 years and 66.5% were women. Fourteen items of OHIP-14 were summarized to one factor explaining 78.6% of total variance and produced the Chronbach alpha coefficient of 0.92. Results from the multivariate model, adjusting for age, sex, type of institutions, ability to pay, and number of teeth present, showed significantly lower OHIP-14 with reporting less than 3 periodontal symptoms (p(O.OOO1), rating their own periodontal health as above average level (p=O.0144), and thinking they don't need any periodontal treatments in the near future (p=O.0148), than their counterparts. The intraclass-corrrelation estimated by the final model was 0.028. Conclusion: This study demonstrates a significant association between self-reported periodontal health status and the oral health-related quality of life.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.22 no.4
• /
• pp.203-214
• /
• 2010

This study numerically investigates the wave control of 2-rowed Impermeable Rectangular Submerged Dike(IRSD) with an object of how to control short-period and solitary waves simultaneously based on the Bragg resonance phenomenon that elevates the wave control performance. The boundary integral method using Green formula and the 3-D one-field Model for immiscible TWO-Phase flows (TWOPM-3D) by 3-D numerical wave flume have been used for the numerical predictions for short-period and solitary waves, respectively. These numerical models were verified through the comparisons with the previously published numerical results by other researchers. Through the parametric tests of numerical experiments for short-period waves, an optimum model of 2-rowed IRSD of a lowest transmission coefficient has been found. Furthermore, the performances of 3-D wave control for solitary waves were evaluated for the various free board, crown widths and gap distance between dikes, and have been compared with those of a single-rowed IRSD. Numerical results show that a 2-rowed IRSD with a less cross sectional area than 1-rowed one improves the wave attenuation performances when it is compared to that of single-rowed IRSD. Within the test frequency ranges of the numerical simulations conducted in this study, 2-rowed IRSD with an optimum gap distance shows an outstanding improvement of the wave attenuation up to 58% compared to that of single-rowed IRSD.

• Magazine of the Korea Concrete Institute
• /
• v.8 no.5
• /
• pp.111-122
• /
• 1996

The effects of external restraint on the thermal stresses i n mass concrete are investigated through a series of parametric study. Two major factors affecting the degree of external restraint such as the ratio of length to height of the placed structure (L/H) and the elastic modulus of base structure ($E_r$) are employed as the parameters in a condition which a placing height H is 1.0m. Various conditions of I,/H and E, are analysed by a FEM program and the relationship between these two parameters is examined. The shape of stress distribution due to the external restraint is shown as linearity on the height direction of the section, and is influenced by L/H, $E_r$, and strength development of placed concrete. The external restraint can be devided by two part. One is an axial restraint and the other is a flexural restraint. When the level of external restraint is low, the structure behavior is mainly governed by flexural restraint, otherwise it is dependent on axial restraint. Comparing the calculated stress by the method of the ACI 207 committee with a finite element analysis, the fbrmer overestimates the external restraint stress when the degree of external restraint is weak, and underestimates when it is strong.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.7
• /
• pp.521-530
• /
• 2009

This study has been made to execute a research in order to lead the improvement of indoor air quality, examining the indoor ventilation characteristics by using a numerical analysis method. To this end an extensive parametric investigation are made according to various external flow variables such as main wind direction and wind speed by season, building layout design, and location of ventilators, etc. in Daedeok Techno Valley, one of large-scaled apartment in Daejeon. It is observed there was a significant difference of main wind direction between summer and winter. The main wind direction in summer was a south wind, and on the contrary the direction in winter is northnorthwest, which is similar to the average main wind direction for 10 years. One of the important calculation results is that the change of wind direction causes a significant effect on the apartment ventilation by the change of pressure difference around each complex of apartment. In case of favorable area of ventilation, the indoor ventilation rate can meet 0.7 ACH from the standard value only with natural ventilation. On the contrary, in other area the value was much lower than the standard value. If the calculation result applies to the design of layout apartment or placement of ventilators, it will be greatly helpful to the energy saving because it can be parallel with the natural ventilation to help securing ventilation rate, not much depending on the mechanical ventilation.

• Journal of the Korean Geosynthetics Society
• /
• v.13 no.4
• /
• pp.97-107
• /
• 2014

Finite element modelling and analysis were conducted for the roll-type steel mats which were placed on loose sand and subjected to a standard truck wheel load in this study. The roll-type steel mats mean that the steel mats can be folded as a circle shape for the carrying to fields in cold regions where workability is limited and are developed for a rapid rehabilitation method for roadway across soft ground which is caused by thawing during the summer season in cold regions. The model is composed of link elements to simulate nonlinear behavior of connections between steel mats, thick shell elements to have flexural stiffness of the steel mats, and springs to simulate characteristics of foundation soils. The structural behaviors of the shell, link elements, and springs were verified at each modelling step through experiment and analysis. Beam and shell analysis without the link elements were conducted and compared to results obtained from the model presented in this study. Significant vertical displacement is shown in the shell model with hinge connections. Therefore, the results demonstrate that the analysis model for the roll-type steel mats on loose sand needs further detail parametric studies.

• Korean Journal of Social Welfare Studies
• /
• v.40 no.3
• /
• pp.41-68
• /
• 2009

Grandparent-grandchildren family adolescents(GGFAs) need to be well discussed because they tend to be more influenced by the negative surroundings than ordinary family adolescents. Over the past few years, several studies have been made on the correlation between the risk factor, the protective factor and the school resilience of GGFAs, but these studies have the limit to explain the only correlation between the one factor and the school resilience. So the purpose of this study was to examine not only the direct effect between the risk factor and the protective factor, but also the parametric path and effect that the one factor has influence on the correlation between the another factor and the school resilience of GGFAs. We investigated the 328 GGFAs in Korea, and the analytic method used was the Structural Equation Modeling(SEM). The followings are the results of this paper. It was found that the model adaptability had a considerable validity by inspecting the SEM, which showed not only the direct effect between the risk factor, protective factor and the school resilience of GGFAs, but also the mediation effect by the protective factor. The risk factors - the indifference of teacher, the negative attachment relationship, melancholy, uneasiness etc - had a negative influence on the school resilience of GGFAs. The protective factors - the supporss etteacher, self-esteem etc - had a positive influence on the school resilience of GGFAs. The protective factors were found to reduce the negative influence on the school resilience of GGFAs.