• Korean Journal of Construction Engineering and Management
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• v.10 no.1
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• pp.114-125
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• 2009

In this study, a design value analysis technique that considered stochastic LCC and stochastic performance evaluation was proposed, and by introducing the concept of reliability analysis, a decision making that secured reliability was supported. The results of this study, which was carried out according to the above objectives and methods, are summarized as follows: 1) The design value analysis procedures and value state function, improved in order to carry out a reliable analysis when evaluating alternate proposals that were extracted after the function definition was complete, were formalized, and in order to secure consistency and efficiency for value evaluation procedures, an evaluation index scheme was proposed; 2) Database collection and analysis were done for a bridge's LCC analysis. As for the collection scope of data, literature of previous research done on a bridge's LCC analysis was used as the basis for analysis, and for securing reliability regarding analysis results and dealing with uncertainty of collected data, the MCS technique was applied; 3) Weights and evaluation ranks for performance evaluation of each of the alternate proposals, as well as LCC analysis model, analysis period, discount rate, user expense, safety inspection and safety diagnosis expense conditions for LCC analysis were proposed. Lastly, a feasibility study was done and conclusion was made about "OO grand bridge and connecting road construction work execution design" project centered on value analysis execution case.

• Spatial Information Research
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• v.23 no.4
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• pp.57-66
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• 2015

At these day, owing to functional limitations and cost issues, used image map in web service have a problem which can not make exactly meet the user needs. This study aims to create an individual map for user suitable purposes using HTML5 technology that implement the vector map creation and its functions with services. The results of this study, the invisible problems of the tilting and rotation functions in image-based map utilizing the existing web environment were solved in HTML5 vector map. And to access the map information, by implementing the function of expressing the background and name data to selectively derive, various results were expressed in the map. Also, as a result of a comparison of performance the time required was measured at 0.88sec which comes in the range of the first loading time between 0.78sec and 7.56sec in a commercial map service, which showed the possibility of its commercialization. compared to 180GB of image maps for the production of a national map index system, the volume to produce a vector map was 2.5GB, a decrease by over 90%, which solved the issue of costs for a storage space. As a result, this study of HTML5 vector map design and implementation presented a plan for providing information suitable for the requirements of the users who use spatial information through utilizing a variety of information and expanding functions.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.273-279
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• 2009

This study was conducted to identify optimal concentrations of N (nitrogen) and K (Potassium) fertilizers on growth, yield and quality of melon (Cucumis melo. L) when they were grown with a fertigation culture in a greenhouse. Three strength (S) levels of fertilizers, including 1 S, 1/2S, and 1/4S were supplied N and K nutrients as using a trickle irrigation system. When the strength level of fertilizers was increased from 1/4S to 1 S, the level of EC (electronic conductivity) in soil was increased. Soil-water tension was ranged between -15 and -20kPa until fruit setting stage, whereas it was ranged between -45 and -50kPa in the later growth stages. In results, N fertilizer had effects on fruit yield and quality. A higher fruit yield was observed when plants were supplied with 1 S and 1/2S level of N fertilizer. The highest yield of marketable fruit, about 5,086kg/10a, was also observed when plants were supplied with 1/2S N fertilizer. A higher net index and sugar content of fruit was observed in the treatments of 1/2S and 1/4S level of N fertilizer compared to 1 S level. In contrast, there was no statistic difference in the yield and quality with three levels of K fertilizer. Results indicate that the 1/2S level for N and 1/4S level for K fertilizer are effective and optimal for the melon plants grown under the fertigation culture in terms of increasing fruit yield and quality and reducing the cost of fertilizers.

• Research in Plant Disease
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• v.14 no.2
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• pp.112-116
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• 2008

Powdery mildew of Paprika caused by Leveillula taurica has been a serious problem in greenhouse. It is an unusual endophytic powdery mildew because the mycelia grow inside the leaf, such that the pale yellow lesions on adaxial surfaces appear first and the white powdery lesion/signs develop later on the corresponding to the spots of the abaxial leaf surface, where the conidiophores are typically emerge through the stomatal opening. Although one foliar application of cooking oil and yolk mixture(COY) to the foliage was not practically effective enough, two or three, weekly application of COY to the foliage at either 0.3 or 0.5% concentration resulted in excellent control against powdery mildew with disease index less/lower than 1, respectively. This treatment could provide protection for three weeks, which, we believe, is not only cost-effective, but also environment-friendly. Powdery mildew fungus was affected by COY treatment quickly which is recognizable in three days. Net photosynthesis and evapotranspiration was remarkably reduced by powdery mildew infection compared to healthy leaves, suggesting that prevention and early protection is the most critical strategy for peak paprika fruit yield. Moreover, COY treatment did not adversely affect the photosynthesis and evapotranspiration of foliages.

• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.163-176
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• 2007

Landslides which is one of the major natural hazard is defined as a mass movement of weathered material rock and debris due to gravity and can be triggered by complex mechanism. It causes enormous property damages and losses of human lift directly and indirectly. In order to mitigate landslide risk effectively, a new method is required to develope for better understanding of landslide risk based on the damaged cost produce, investment priority data, etc. In this study, we suggest a new evaluation method for slope stability using risk analysis. 30 slopes including 10 stable slopes, 10 slopes of possible failure and 10 failed slopes along the national and local roads are examined. Risk analysis comprises the hazard analysis and the consequence analysis. Risk scores evaluated by risk analysis show very clear boundaries for each category and are the highest for the failed slopes and the lowest for the stable slopes. The evaluation method for slope stability suggested by this research may define the condition and stability of slope more clearly than other methods suggested by others.

• International Journal of Highway Engineering
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• v.17 no.1
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• pp.17-24
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• 2015

PURPOSES : Recently, crack, rutting, and stripping problems from the surface of asphalt pavements in National highway are observed and they affect the drivers to feel uncomfortable on the road. Surface treatments are recommended to use in distressed pavements due to cost-effective, and improvement of surface performance. The purpose of this study is to evaluate the performance of micro-surfacing and polymer slurry seal treatments for distressed asphalt pavements. METHODS : Surface conditions and friction resistance are evaluated for asphalt pavements treated with micro-surfacing and polymer slurry seal mixes in National highway 30 line and 34 line. Visual observation is conducted and surface performance is measured by PES (Performance Evaluation Surveyor) in terms of crack ratio, rutting and IRI(International Roughness Index). BPN(British Pendulum Number) is measured by BPT(British Pendulum Tester) to evaluate the friction resistance in the field. RESULTS : The surface evaluation results are presented for asphalt pavement treated with micro-surfacing and polymer slurry seal treatments in National highway 30 line and 34 line. Based on the visual observation, micro-surfacing and polymer slurry seal treatments show better improvements in terms of cracks and stripping. Based on the surface conditions measured by PES vehicle, the surface performance of micro-surfacing treatments improves from 53.3% to 54.2% and the surface performance of polymer slurry seal treatments improves from 21.6% to 59.7%. However, the friction resistance of both micro-surfacing and polymer slurry seal treatments decreases from 2.5% to 6.7%. Further, it should be verified to produce the surface exposed with aggregates during the construction process of both treatment methods in the field. CONCLUSIONS : Based on the performance evaluation results in the filed, the surface performance of asphalt pavement treated with micro-surfacing and polymer slurry seal treatments improves from 21.6% to 59.7%. While, the friction resistance of asphalt pavement treated with micro-surfacing and polymer slurry seal treatments does not improve. It can be concluded that current micro-surfacing and polymer slurry seal treatments would improve surface performance but would not improve the friction resistance.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.7-16
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• 2004

The purpose of this study was to find the characteristics of travel behavior and accessibility in terms of spatial structure. We analyzed travel behaviors and accessibility using a mode choice model and the Complementary Accessibility Index(CAI). The urban spatial structures that were compared were a compact city (CC) versus a sprawled city (SC), and high residential density districts (HD) versus low residential density districts (LD). First, CC and HDs residents had a shorter commuting distance than the CC and LDs residents. Second, behavior models showed that the use of Private cars for commuting in SCs was found to be greater than private car use in CCs, and that public transportation modes would be encouraged in CCs. Third, changes associated with the time and cost of commuting by private car generally affect the demand for public transportation modes in the CC. Also, analysis of cross elasticity suggests that changes of subway travel time affect the demand for buses very elastically. Fourth, the CAI of SC and LD were superior to the CC and HD even though the SC inefficient urban forms in terms of spatial structure. So, the spatial distribution of population density was also found to be an important factor affecting accessibility and energy savings.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.191-200
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• 2003

This paper presents the rheological properties of bitumen for reducing negative skin friction. The bitumen has been widely used due to both the cost and construction effectiveness. Also, it is well known that the use of bitumen for reducing negative skin friction renders the best results among other available methods. Three different modified bitumens were used for the testing programs. The physical tests include the penetration, the softening point and penetration index. The rheological tests include phase angle, complex modulus, creep tests and flow tests. The tests were conducted at four different temperatures(15, 30, 45 and 6$0^{\circ}C$) in order to simulate the field condition. The test results were analyzed using the phase angle, G$^*$/sin $\delta$, creep compliance and shear viscosity. The result of tests showed that the phase angle increased and G$^*$/sin $\delta$ decreased with the increase of temperature. The creep compliance increased as the loading time increased. The difference of the creep compliance is detected as the time and temperature are varied, however, the difference of the shear viscosity is not significant among the samples tested in this study. The rheological properties of the bitumen also showed that the physical testing method and the temperature dependant testing method are somewhat limited to showing and expressing the full rheological properties of the modified bitumen. The introduction of the time and the temperature dependent testing method is necessary to find out the full rheological properties of the modified bitumen.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1553-1561
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• 2004

Two feeding trials were conducted with 128 pullets from 4 to 20 weeks of age and 96 laying hens from 23 to 63 weeks of age to evaluate the effects of scavenging and type of protein supplement on the feed intake and performance of improved pullets and laying hens. The experiments had a completely randomized design with four dietary treatments and four replicates. Treatments were: Control (Cont), scavenging but with access to a balanced concentrate at night; confinement (CF) and given the control feed ad libitum; scavenging and supplemented at night with the control feed, but with soybean meal replaced by cassava leaf meal (CLM); scavenging and supplemented at night with the control feed, but with fishmeal replaced y soybean meal (SBM). The mean daily dry matter (DMI), metabolizable energy (MEI) and crude protein intakes (CPI) of the pullets and laying hens, respectively, were 28%, and 18% higher for the confinement treatment (CF) compared to the scavenging treatments (p<0.001). The DMI, MEI and CPI of the pullets were not significantly different among scavenging treatments (p>0.05), but for the layers DMI, MEI and CPI were significantly higher for the CLM and SBM treatments compared to the Cont treatment (p<0.001). In the growing period, the average daily weight gain (ADG), supplement feed conversion ratio (FCR) and supplement feed cost/kg eggs (FCS) were not significantly different for CF compared to Cont, and among scavenging treatments (p>0.05). In the laying period, the hen-day production was significantly lower, and supplement FCR and FCS significantly higher for the CF compared to the scavenging treatments (p<0.001). Egg weight, and yolk, albumen and shell percentage and shape index were not significantly different among the scavenging treatments (p>0.05). However, shell and yolk percentages were significantly lower for the CF compared to the Cont treatment (p<0.01). Mortality was significantly higher for the CF compared to the scavenging treatments for pullets, and was significantly lower for the CF compared to scavenging treatments for laying hens (p<0.001). It was concluded that scavenging pullets and layers were getting around 28% and 18%, respectively, of their nutrient requirements from scavenging activities, resulting in correspondingly lower supplement feed conversion ratios and feed costs. Daily gains of the pullets were not affected by scavenging or protein supplement, but egg production and mortality were lower for the confined hens.

• Journal of KIISE
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• v.42 no.4
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• pp.504-511
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• 2015

Recently, the amount of data is rapidly increasing with the popularity of the SNS and the development of mobile technology. So, it has been actively studied for the effective data analysis schemes of the large amounts of data. One of the typical schemes is a Voronoi diagram based on kNN join algorithm (VkNN-join) using MapReduce. For two datasets R and S, VkNN-join can reduce the time of the join query processing involving big data because it selects the corresponding subset Sj for each Ri and processes the query with them. However, VkNN-join requires a high computational cost for constructing the Voronoi diagram. Moreover, the computational overhead of the VkNN-join is high because the number of the candidate cells increases as the value of the k increases. In order to solve these problems, we propose a MapReduce-based kNN-join query processing algorithm for analyzing the large amounts of data. Using the seed-based dynamic partitioning, our algorithm can reduce the overhead for constructing the index structure. Also, it can reduce the computational overhead to find the candidate partitions by selecting corresponding partitions with the average distance between two seeds. We show that our algorithm has better performance than the existing scheme in terms of the query processing time.