• Journal of Korean Society of Environmental Engineers
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• v.31 no.3
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• pp.193-202
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• 2009

This study was conducted to identify the magnitude of first flush in small city urban area and to provide the basic information on the criteria of stormwater runoff management. Monitoring site was surrounded by residential area in Gumi city near to national industrial complex and the monitoring period was three months. Total watershed area was 24.9 ha, where 80% of the area is impervious (asphalt of pavement type). Periodic monitoring of conventional water quality parameters were conducted with six times of rainfall period. Event mean and site mean concentrations for all the parameters were calculated based on the analytical results. Particle size distribution was 9.82 ${\mu}m$ for $D_{0.1}$, 38.99 ${\mu}m$ for $D_{0.5}$ and 159.61 ${\mu}m$ for $D_{0.9}$ respectively. First flush phenomenon was detected highly in particulate solids than dissolved ones. The first flush criteria results by mass first flush contained between 44.4% to 58.5% pollutant mass during the first 30% of runoff volume. Mass first flush ratio and particle size distribution obtained in this study are expected to provide the basic information for the design and operation of non-point source treatment facility.

• Journal of the Korean GEO-environmental Society
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• v.15 no.1
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• pp.53-62
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• 2014

In Korea, in general, separation distance between existing parallel tunnels was set at two to five times as distant as the diameter of the tunnels according to ground conditions. Recently, however, actual applicability of closely spaced parallel tunnels whose distance between tunnel centers was shorter than the diameter has increased due to environmental damages resulting from massive cutting, restriction in purchase of required land, and maintenance of linear continuity. In particular, when the pillar width of tunnel decreases, the safety of pillars affects behaviors of the tunnel and therefore the need for diverse relevant studies has emerged. However, research so far has been largely confined to analysis of behavior characteristics of pillars, or parameters affecting design, and actually applicable and quantitative data have not been presented. Accordingly, in order to present a stability evaluation method which may maximally reflect construction conditions of spots, this study reflected topographical and stratigraphic characteristics of the portal part with the highest closeness between the tunnels, simulated multi-layer conditions with rock mass and complete weathering, and assessed the degree of effect the stability of pillars had on the entire tunnels through numerical analysis according to changes in pillar width by ground strength. This study also presented composite analysis result on ground surface settlement rates, interference volume rates, and average strength to stress and a formula, which may be applicable to actual work, to evaluate safety rates of closely spaced parallel tunnel pillars and minimum pillar width by ground strength based on failure criteria by Hoek-Brown (1980).

• Journal of Distribution Science
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• v.13 no.10
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• pp.93-99
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• 2015

Purpose - It has been argued that the regulations restricting entry and opening hours of General Super Markets and Super Super Markets have not been as effective as expected. In contrast, the win-win item scheme that appeared recently has the advantage that it could raise the effectiveness of the system in that win-win items are in principle resigned on the basis of bilateral agreements. This study analyzes the win-win item agreement made between Homeplus at Hap-jung and small traditional markets to examine the practical effectiveness of the win-win item scheme. While existing literature studying the regulatory effects have concentrated on the restrictions around store entry or opening hours of large retailers, it can be said that there have been few empirical studies on the effect of win-win items agreement with large retailers. Research design, data, and methodology - Homeplus at Hap-jung made a win-win items agreement with nearby small traditional market traders in 2013. In accordance with this voluntary agreement, Homeplus started by limiting its sales to 15 win-win items. The survey was conducted through one-on-one interviews, April 14 to May 2, 2014, by a professional public opinion research agency. The interviews were targeted at small business retailers in the nearby traditional market. We divided the traditional markets near Homeplus at Hap-jung where the win-win item agreement was achieved into two groups, win-win item agreement markets and non win-win item agreement markets, to compare the performance difference between the two groups. Results - To determine the change in sales of the 15 win-win items, we examined the performance difference between the two groups using two criteria (compared with similar items, and compared to sales volume a year ago). The results show that the individual sales of win-win items in the win-win item agreement markets are more likely to increase than in the non win-win item agreement markets. Total sales volume of individual stores in the agreement markets also showed a more significant increase compared to a year ago than those in non win-win item agreement markets. Conclusions - Contrary to the existing retail regulations that have one-sided and uniform characteristics, it can be pointed out that the win-win item scheme has the effect of increasing the success of the system itself because it is done on the basis of mutual agreement between General Super Markets and traditional markets. The empirical results of this study can be said to support this conjecture. For the successful settlement of a win-win items agreement, the following points should be reviewed. First, it requires a great effort from the selection process of win-win items in order to improve the effectiveness of the agreement. Second, the existing General Super Markets customers should be introduced to the traditional markets or small shops to increase the sales of win-win items. Therefore, voluntary effort is essentially required from the traditional markets to engage customers.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.5 no.1
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• pp.107-124
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• 1998

Based on King's goal attainment theory, this research deals with applying nursing intervention of mutual goal settings to gastrectomy patients. It tests the effects of nursing intervention, according to the patients' health locus of control, suggested as external boundary criteria for the theory by employing a quasi-experimental design which consists of a pretest-posttest non-equivalent control and experimental groups. The subjects of this research were 62 gastrectomy patients hospitalized at Y medical center and the experimental and control groups consisted of 31 subjects. The experimental group received nursing intervention at the mutual goal setting of 5 times from the day before the surgery to the 5th day after the surgery, while the control group received only routine nursing care. Recovery indicators of both groups were measured and compared. Measurement variables included patients' characteristics, health locus of control, forced vital capacity, forced expiratory volume in one second, peak expiratory flow, bowel movement recovery, mobility recovery, level of pain, patients' stress and patients' satisfaction. Data were analyzed using SPSS statistical package and the hypotheses were tested by ANOVA and ANCOVA. Results of the analyses are summarized as follows : 1) Internal health locus of control had higher effects of the nursing intervention of mutual goal setting than external health locus of control on pulmonary ventilatory functions of forced vital capacity, forced expiratory volume in one second, and peak expiratory flow. 2) There was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the bowel movement recovery between the internal and external health locus of control. 3) There was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the mobility recovery between the internal and external health locus of control. 4) There was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the level of pain between the internal and external health locus of control. 5) There was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the level of stress between the internal and external health locus of control. 6) There was a statistically significant difference in the effects of nursing intervention of mutual goal setting on the level of satisfaction with provision of nursing information between the internal and external health locus of control, and there was no statistically significant difference in the effects of nursing intervention of mutual goal setting on the level of satisfaction with outcome of nursing between the internal and external locus of control. On the basis of the research results, the following are recommended : 1) Repeated research on responses to health locus of control is necessary. 2) Not only the effectiveness of nursing intervention in acute recovery periods, but also the long term effects are to be investigated. 3) The development of instruments is needed to accurately measure mutual goal setting regarding postoperative deep breath, coughing, early ambulation, etc. so that the relationship among the postoperative recovery indicators may be explored. 4) It is required that an instrument be developed to measure perception which facilitates goal attainment in the interactive setting between patients and nurses.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6D
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• pp.931-936
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• 2008

Surveying by using terrestrial LiDAR(Light Detection And Ranging) is more rapid than by using total station which enables tunnel section profile surveying to be done in suitable time and minimize centerline error, occurrence of overcut and undercut. Therefore, utilization of terrestrial LiDAR has increased more and more in section profile survey and measurement field Moreover, studies of terrestrial LiDAR for accurate and efficient utilization is now ongoing vigorously. Average end area formula, which was generally used to calculate overcut and undercut, was compared with existing methods such as total station survey and photogrammetry. However, there are no criteria of spacing distance for calculating overcut and undercut through terrestrial LiDAR surveying which can acquire 3D information of whole tunnel. This research performed reverse engineering to decide optimal spacing distance when surveying tunnel section profile by comparing whole tunnel volume and tunnel volume in difference spacing distance. This result was utilized to produce CAD drawing for the test tunnel site where there is no design drawings. In addition to this, efficiency of LiDAR and accuracy of CAD drawing was compared with targetless total station surveying of tunnel section profile. Finally, error analysis of target coordinate's accuracy and incidence angle was done in order to verify the accuracy of terrestrial LiDAR technology.

• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.23-30
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• 2006

Emulsified Asphalt Mixture(EAM) is more environmentally-friendly and cost-effective than typical Hot Mix Asphalt (HMA) because EAM does not produce carcinogenic substances, e.g., naphtha, kerosene, during the both of manufacturing and roadway construction process. Also, it does not require heating the aggregates and asphalt binder. However, EAM has some disadvantages. Generally EAM has a less load bearing capacity and more moisture susceptibility than conventional HMA. The study evaluated a Fiber modified EAM (FEAM) to increase load bearing capacity and to decrease moisture susceptibility of EAM. Modified Marshall mix design was developed to find Optimum Emulsion Contents (OEC), Optimum Water Contents (OWC), and Optimum Fiber Contents (OFC). A series of test were performed on the fabricated specimen with OBC, OWC, and OFC. Tests include Marshall Stability, Indirect Tensile Strength, and Resilient modulus test. Comparison analyses were performed among EAM, Fiber modified EAM (FEAM), and typical HMA to verify the applicability of EAM and FEAM in the field. Test results indicated that both of EAM and FEAM have an enough capability to resist medium traffic volume based on the Marshall mix design criteria. Also the study found that fiber modification is effective to increase the load bearing capacity and moisture damage resistance of EAM.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.4
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• pp.76-91
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• 2017

The Area of a domestic railway station is designed based on the 4-step traffic demand forecasting model with the average daily passenger count as one of its parameter. However, nowadays, due to increasing rate of railway station's function, the non-passengers are increasing. In order to consider those non-passengers who aren't using trains, assumed volume are added to the average daily passenger count of station to estimate the area, but the criteria being applied has no concrete basis. Therefore, this study aimed to recalculate the increasing non-passenger rate based on actual survey data of station users in any type of railway station to obtain the optimum area. Subsequently, the the design area was performed through pedestrian simulation. According to the result of the simulation, it was found that the total space of the exciting railway stations can be reduced up to 45% and will still satisfy the level of service(LOS) requirement.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.80-88
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• 2023

Ensuring safety in the designing of manufacturing and handling facilities for low-density polyethylene (LDPE) is difficult because there are no standards for the dust explosion characteristics of LDPE. In this study, a dust explosion test was performed on two dust samples collected from a bag filter (LDPE 1) during the LDPE manufacturing process and sedimentary dust (LDPE 2) leaked outside a facility such as a silo, and the LDPE 2 explosion test results were summarized. Particle size analysis showed that the volume-based particle diameter (median) was 95.04 ㎛ and the number density was 0-1 ㎛. The maximum explosion pressure (P_max) was 6.6 bar, and the maximum rate of explosion pressure rise was 366 [bar/s] at 1500 g/m³. Accordingly, the dust explosion index (K_st) was 99.4 bar·m/s, which was confirmed as ST-1 grade. Moreover, the minimum ignition energy and minimum ignition temperature was 10 mJ and 450 ℃, respectively. Currently, manufacturing and handling design is based on the characteristic values of high-density polyethylene (HDPE). However, as the test results show that LDPE 2 dust has a higher risk than HDPE (particle diameter 61.6 ㎛), caution is required when using the HDPE design criteria in the LDPE manufacturing process.

• The Korean Journal of Air & Space Law and Policy
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• v.27 no.2
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• pp.67-106
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• 2012

Today air traffic at the airport is complicated including a significant increase in the volume of air transport, so aviation accidents are constantly occurring. Therefore, we should newly recognize importance of the Air Traffic Safety, the core values of the Air Traffic. The location of airport that is the basic infrastructure of the air traffic and the security of safety for facilities and equipments are more important than what you can. From this dimension, I analyze the step-by-step safety factors that are taken into account in the airport development projects from the construction or improvement of the airport within the current laws and institutions and give my opinion on the enhancement of safety in the design and construction of airport. The safety of air traffic, as well as airport, depends on location, development, design, construction, inspection and management of the airport including airport facilities because we have to carry out the national responsibility that prevents the risk of large social overhead capital for many and unspecified persons in modern society through legislation regarding intervention of specialists and locational criteria for aviation safety from the planning stage of airport development. In addition, well-defined installation standards of airports and air navigation facilities, the key points of the airport development phase, can ensure the safety of the airport and airport facilities. Of course, the installation standards of airport and air navigation facilities are based on the global standard due to the nature of air traffic. However, to prevent the chaos for the safety standards in design, construction, inspection of them and to ensure the aviation safety, the safety standards must be further subdivided in the course of domestic legislation. The criteria for installation of the Air Navigation facilities is regulated most specifically. However, to ensure the safety of the operation for Air Navigation Facilities, performance system proved suitable for the Safety of Air Navigation Facilities must change over from arbitrary restrictions to mandatory restrictions and be applied for foreign producers as well as domestic producers. Of course, negligence of pilots and defective aircraft maintenance lead to a large portion of the aviation accidents. However, I think that air traffic accidents can be reduced if the airport or airport facility is perfect enough to ensure the safety. Therefore, legal and institutional supplement to prioritize the aviation safety from the stage of airport development may be necessary.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.115-127
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• 2019

The low-flow grouting injection technique, the target construction method for this study, is a method of pouring mortar into the ground by non-emission replacement principle, which can be expected to increase the density of the ground, and, in some cases, be used as a base file using the strength of the high injection solids, along with low noise, low pollution, and high durability. To verify that the dynamic characteristics of the ground are improved by the low-flow injection technique, the test work was conducted on the site and physical tests were performed, and the quality of the improvement formed in the ground was verified through the indoor test on the core and core recovery rate was analyzed. The density logs test layer calculated the volume density of the ground layer by using the Compton scattering of gamma-rays, and the sonic logs was tested on the ground around the drill hole using a detector consisting of sonar and receiver devices inside the drill hole. As a result of the measurement of the change in physical properties (density and sonic logs) before and after grouting, both properties were basically increased after infusion of grout agent. However, the variation in density increase was greater than the increase in speed after grouting, and the ground density measurement method was thought to be effective in measuring the fill effect of the filler. Strength and core recovery rates were measured from specimens taken after the age of 28 days, and the results of the test results of the diffusion and strength test of the improved products were verified to satisfy the design criteria, thereby satisfying the seismic performance reinforcement.