• Journal of Environmental Science International
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• v.23 no.5
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• pp.781-786
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• 2014

Growth and physiological disorders caused by abnormally low temperatures were evaluated in pepper, an important field crop in Korea. In addition, the effects of chemical treatment using glutamine was verified on minimizing the damages by low temperature. The growth of pepper plants in stem length and diameter was suppressed as the temperature decreased from $25^{\circ}C$, and the suppression level was the highest for plants grown for 90 days at $20^{\circ}C$. However, root growth was not affected by the different temperatures. The number of leaf and leaf area decreased at the temperatures below $25^{\circ}C$, an optimum temperature for growth. Fresh weight and dry weight decreased for plants grown at $20^{\circ}C$. Pepper fruit yield also decreased by 11% at $20^{\circ}C$ in comparison to $25^{\circ}C$. Falling blossom rate was different depending on the growth temperature, and the rate was 27.2% at $25^{\circ}C$, 35.2% at $22.5^{\circ}C$, and 41.0% at $20^{\circ}C$, indicating that falling blossom rate increased as temperature decreased. Different growth temperatures did not affected on the level of symptom of calcium deficiency and Phytopathora blight. Falling blossom was severe at abnormally low temperature of $20^{\circ}C$, but the treatment of glutamine reduced falling blossom rate and increased the yield by 7.0% as compared to control. The optimum concentration of glutamine treatment was 10 mg/L for yields.

• Journal of the Korean Society of Clothing and Textiles
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• v.9 no.3
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• pp.45-51
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• 1985

The purpose of this study is to research into the thermal condition and the weight of clothes suitable for the officers engagged in light works in an air-conditioned room in summer. The Major findings are as follows: 1. Thermal conditions of the working environment are $24.5^{\circ}C$ (Dry bulb temp.), $68\%$ (Relative humidity) and 2.6m/sec (Air Velocity). 2. Total clothing weights are 416.6 g/$m^2$ (male) and 340.9 g/$m^2$ (female). Underwear weights are 96.8g/$m^2$ (male) and 85.1g/$m^2$ (female). The latter turned out to be statistically significant in Sexual difference. 3. Means of the thermal sensation are 3.0 (comfortable; male) 2.7 ('Slightly cool' -'Comfortable'; female) and the relationship between clothing weights and thermal sensation proves to be significantly correlated in the case of female. 4. $66.7\%$ of the women and $37.1\%$ of the men feel sensation of coldness at the body's specific area and $79.5\%$ of the women and $54.3\%$ of the men reveals air-conditioning disturbance. 5. As the thermal sensation is close to 'cool-cold', sensation of coldness or air conditioning disturbance are showed up more frequently which is reversely related with weight of under-wear. It is also proved that air conditioning disturbances are influenced by sexual difference in addition to sensation of coldness and thermal sensation. 6. According to the result of experiment, we can have the idea that at condition $X_1$, the drop of limbs' skin temp. is remarkable. At condition $X_2$ skin temp. for distal limbs and mean skin temp. are raised and the falling degree is similar. At condition $X_3$, mean skin temp. and distal skin temp. are remarkably raised, and the falling degree decreases and the beats of pulse rate increase and diastoric blood pressure is lowered.

• The Journal of Information Technology
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• v.9 no.4
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• pp.65-74
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• 2006

The back propagation of neural networks has the problems of falling into local minimum and delay of the speed by the iterative learning. An algorithm to solve the problem and improve the speed of the learning was already proposed in[8], which updates the learning parameter related with the connection weight. In this paper, we propose the algorithm generating initial weight to improve the efficiency of the algorithm by offering the difference between the input vector and the target signal to the generating function of initial weight. The algorithm proposed here can classify more than 98.75% of the handwritten digits and this rate shows 30% more effective than the other previous methods.

• Clinical and Experimental Pediatrics
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• v.54 no.11
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• pp.429-435
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• 2011

Although Korean population has been growing steadily during the past four decades, the nation is rapidly becoming an aging society because of its declining birth rate combined with an increasing life expectancy. In addition, Korea has one of the lowest fertility rates in the world due to fewer married couples, advanced maternal age, and falling birth rate. The prevalence of low birth weight infants and multiple births has been increased compared with the decrease in the birth rate. Moreover, the number of congenital anomalies is expected to increase due to the advanced maternal age. In addition, the number of interracial children is expected to increase due to the rise in the number of international marriages. However, the maternal education level is high, single-mother birth rate is low, and the gender imbalance has lessened. The number of overweight babies has been decreased, as more pregnant women are receiving adequate prenatal care. Compared to the Asian average birth weight, the average birth weight is the highest in Asia. Moreover, the rate of low birth weight infants is low, and infant mortality is similarly low across Asia. Using birth data from Statistics Korea and studies of birth outcomes in Korea and abroad, this study aimed to assess the changes in maternal and infant characteristics associated with birth outcomes during the past four decades and identify necessary information infrastructures to study countermeasures the decrease in birth rate and increase in low birth weight infants in Korea.

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.261-271
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• 2003

A condition evaluation procedure for the pavement foundations using multi-load level Falling Weight Deflectometer(FWD) deflections is presented in this paper. A dynamic finite element program incorporating a stress-dependent material model, was used to generate the synthetic deflection database. Based on this synthetic database, the relationships between surface deflections and critical responses, such as stresses and strains in base and subgrade layers, have been established. FWD deflection data, Dynamic Cone Penetrometer(UP) data, and repeated load resilient modulus testing results used in developing this procedure were collected from the Long Term Pavement Performance (LTPP) and North Carolina Department of Transportation (NCDOT) database. Research effort focused on investigation of the effect of the FWD load level on the condition evaluation procedures. The results indicate that the proposed procedure can estimate the pavement foundation conditions. It is also found that structurally adjusted Base Damage Index (BDI) and Base Curvature Index (BCI) are good indicators for the prediction of stiffness characteristics of aggregate base and subgrade respectively. A FWD test with a load of 66.7 kN or less does not improve the accuracy of this procedure. Results from the study for the nonlinear behavior of a pavement foundations indicate that the deflection ratio obtained from multi-load level deflections can predict the type and quality of the pavement foundation materials.

• Journal of the Korean GEO-environmental Society
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• v.22 no.3
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• pp.45-51
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• 2021

The evaluation of the degree of compaction of the embankment area, which accounts for most of highway earthworks, is generally performed by a flat plate loading test. The plate loading test is a traditional test method and has high reliability in the field. However, as reaction force equipment must be carried out and it takes about 40 minutes per site during the test, there may be limitations in managing the entire expanse of earthworks. Meanwhile, in order to overcome this, the Ministry of Land, Infrastructure and Transport proposed a simple method of evaluating the level of compactness in the provisional guidelines for compaction management of the packaging infrastructure in 2010. However, it has not been utilized at the highway construction site until now, 10 years later. Therefore, this study attempted to verify the utility of the compaction evaluation method using LFWD (Light Falling Weight Deflectometer) of the impact loading method among the test methods suggested in the provisional guideline. To this end, the correlation was derived by conducting a plate loading test and an LFWD test for each site property and compaction degree. As a result of the test, there was no consistency of test data in the ground with a relative compaction of 80% or less. However, it was confirmed that the correlation has a tendency to increase beyond that. If the test method or test equipment is improved to ensure the consistency of the test values of the impact loading method in the future, it will play a big role in solving the blind spot for compaction management in the earthworks.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.797-804
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• 2006

A development of regression model for asphalt concrete pavements using Falling Weight Deflectometer deflections is presented in this paper. A backcalculation program based on layered elastic theory was used to generate the synthetic modulus database, which was used to generate 95% confidence intervals of modulus in each layer. Using deflection basins of FWD data used in developing this procedure were collected from Pavement Management System in flexible pavements. Assumptions of back-calculation are that one is 3 layered flexible pavement structure and another is depth to bedrock is finite. It is found that difference of between 95% confidence intervals and modulus ranges of other papers does not exist. So, the data of 95% confidence intervals in each layer was used to develop multiple regression models. Multiple regression equations of each layer were established by SPSS, package of Statics analysis. These models were proved by regression diagnostics, which include case analysis, multi-collinearity analysis, influence diagnostics and analysis of variance. And these models have higher degree of coefficient of determination than 0.75. So this models were applied to predict modulus of domestic asphalt concrete pavement at FWD field test.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.980-986
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• 2004

So far systematic and reliable methods for the investigation of track substructure (ballast and subgrade) are not developed yet. This study presents the applicability of GPR (Ground Penetrating Radar) and PBS (Portable Ballast Sampler) to the evaluation of railway trackbed conditions. Including FWD (Falling Weight Deflectometer) often used to evaluate the subsurface conditions of pavement, the standard system for assessing trackbed conditions will be developed in the future.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.781-786
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• 1999

One of the major causes of concrete pavement deterioration is the loss of support due to erosion and pumping of subbase and subgrade. In this study, procedures for the detection of voids under concrete pavement slab are presented using nondestructive test method such as FWD(Falling Weight Deflectometer) and GPR(Ground Penetration Radar). The deflection responses of concrete slab obtained in FWD field test are analysed for determining the presence of void. Also, reflection responses in GPR test are interpreted. It was concluded that these procedures are available for detecting the viods under concrete pavement slab.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1113-1118
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• 2004

Ballasted track is constructed in consideration of the maintenance. The application time and frequency of MTT(Multiple Tie Tamper) and BS(Ballast Cleaner) depend on track geometry measurements. This paper presents the application of Ground Penetrating Radar(GPR), Falling Weight Deflectometer(FWD), and Portable Ballast Sampler (PBS) to evaluate the effects of track geometry due to substructure deterioration and to build a reliable substructure evaluation system.