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This study evaluates a novel biopolymer-based material reinforcement method. A real-scale experiment minimizing flood disasters and economic losses incurred by the collapse of river levees due to overtopping was conducted. At the Andong River Experiment Center, lateral overflow was reproduced to induce levee collapse using sand, reinforced novel materials, and vegetation levees represented as cases 1, 2, and 3, respectively. The flow in the upstream and downstream areas was measured, and fluctuations in the lateral overflow discharge were calculated using an acoustic Doppler current profiler. To quantitatively verify the performance of this method, the collapse delay effect based on the surface loss rate of the levee slope was analyzed using image pixel analysis and three-dimensional point cloud modeling. Comparing the collapse delay effect of the new-material levee with that of the non-reinforced levees, we found a time delay of approximately 2.7–7 times from the occurrence of overtopping via the lateral flow to the end of the test. These results indicate that we can secure time for emergency repairs and operations by reinforcing the levee surface using the material proposed in this study. These research findings are expected to provide the basis for the proper design and construction of river levees.

MICE (Meetings, Incentives, Conventions and Exhibitions/Events) have been established as one of the most important industries. Limited attention, however, has been given to understanding the underlying mechanisms of a sustainable market environment. In order to build such an environment, this research investigates a way to enhance the identity between local businesses and the MICE industry that make up the MICE environment by employing the brand concept in marketing. This study examines the effect of venue name and type of events being exposed on brand formation. The main purpose of this study is to investigate the relationship between brand identity and the impact on residents&rsquo, perceived brand value. The findings of this research suggest that consistent exposure of content-specific brand names and similar types of events increases the identity between local businesses and the MICE industry, and the identity mediates the relationship.

Flood damage has aggravated recently owing to artificial structures in high flow rare areas such as small rivers, which can lead to secondary damage. In this regard, studies are required to examine the conventional design criteria formulas to secure the stability of structures such as weirs and drop structures. Although studies on the stability of these structures have been conducted through small-scale experiments, few empirical studies have investigated the hydraulic phenomena occurring near actual artificial structures. In this study, we fabricated real-size models of weir and drop structure at the Andong River Experiment Center and investigated the flow patterns around the structures by applying the particle image velocimetry analysis technique with a flow tracker. We also measured the scour length in the waterspout section when the structures are overflowing, and compared it with the values calculated using the formula. Consequently, as the supply flow increases, the result is different from the value calculated using the formula given in the existing design standard, and it is judged to be inappropriate for a small stream area with high flow rate. Thus, it is necessary to consider the design factors such as energy gradient and the flow amount per unit width into weir and drop structure as well as the existing design factors in designing an apron section for a weir and drop structure.

Various river projects are underway in small rivers in Korea that typically have natural flows. However, recent findings have shown that damages could be aggravated by structures such as weirs and drop structures during flood incidents. Experimental studies for securing the stability of flood control for these artificial structures have been insufficient, and designs applying the existing domestic design standards would not be suitable for the steep flow sections such as the actual small rivers, possibly aggravating the damages. The present study involved hydraulic model experiments conducted in a laboratory to investigate the surrounding flow patterns according to the river bed slope at the downstream part of the weir model. Further, the scour characteristics in the apron section during the overflow of the structure were analyzed to determine the appropriateness of the apron length. Thus, as the upstream river bed slope gradually increased, the experimental scour length deviated more from the design criteria formula. The results suggest that both the formula suggested by the National Construction Research Institute and Bligh’s formula presented in the River Design Criteria are not suitable for steep-slope rivers, such as small rivers in Korea, because both formulas were proposed based on the seepage line distance and river bed materials without considering the slope of the river bed. Thus, in designing the apron and bed pitching of weirs and drop structures, the river bed slope, scour characteristics of weir overflow, and existing design factors should be comprehensively considered to devise a design formula appropriate for environment of the small rivers in Korea.

Recently, urban inundation disasters resulting from torrential rain have led to serious problems in many countries worldwide. To mitigate the damage of urban inundation, various structural strategies have been carried out, one of which is the creation of underground storage chambers attached to sewerage systems. In this strategy, part of the storm water within a sewer pipe is diverted over the side weir into the storage chamber. The function of this storage chamber is to manage the storm water runoff at a developed site to prevent flooding, and it is essential for providing a temporary storage area for excess storm water. In this study, the differences in the effects of the storage chamber using an urban inundation model due to several conditions such as the rainfall type, changes in the weir shape, installation locations that have different areal features, and changes in the storage capacity volume are verified. Lastly, a suitable installation site is verified via assessments of the inundation damage costs. The results show that the criteria for the degree of mitigation that can be expected in these conditions.

This study draws on the psychological tenets of implicit self-theories, which differentiate between individuals with entity versus incremental orientations, to deepen our understanding about how consumers evaluate luxury-brand advertising appeals. Our findings show that entity theorist consumers are more attracted to the symbolic value appeals of luxury brands, whereas incremental theorists are more attracted to functional value appeals. Furthermore, we show how consumers' implicit self-theories can be purposively primed by managers with the textual elements of a luxury-brand advertising message to increase its effectiveness, which provides useful implications for designing and executing effective luxury advertising.

This study proposes an earthen levee reinforcement method with a new biopolymer-based material to prevent levee scour and breach. It is an eco-friendly method that can efficiently protect the levee slope as it enhances soil strength, even at a very low concentration of biopolymer, and has high resistance to surface runoff in addition to promoting vegetation growth. The function and effectiveness of this method were demonstrated through an overflow-based semi-scale experiment in a previous study. In this study, we examined the effect of biopolymer-mixed soil layer on levee stability against an overflow-induced breach. In these experiments, biopolymer-mixed soils were sprayed on the crest and land-side levee surface. Two full-scale tests were conducted (2.5&ndash, 2.7 m high and 14 m wide on bottom). Case 1 (control case) consisted of bare sand without any treatment, while Case 2 consisted of a 1.0% biopolymer-mixed soil sprayed on the crest and landside slope of the levee and turf put on it. By applying an image analysis technique, we analyzed the breach phenomenon and breach retardation effect of the levee treated with a biopolymer and covered with vegetation. In this experiment, the slope loss rate of Case 2 was retarded 1.5 to 2.3 times over time as compared to Case 1. During the experiment, we observed that soil erosion followed through the narrow water channel formed by the stripped turfs. This means that the grasses did not root firmly enough to protect the surface. In this regard, although the experimental results may seem unsatisfactory, the biopolymer was found to help improve erosion retardation. In 2020, we will conduct more experiments with different compositions and concentrations of the biopolymer regardless of levee vegetation. With this research, we expect to confirm that the new technology of using biopolymer-treated soils is promising for solving the levee overflow breach problem.

Cement and other similar compounds have been used to prevent a levee breach during a flood. However, the demand is increasing for eco-friendly and sustainable alternatives to replace the conventional method for levee stabilization and strengthening. To improve the durability and environmental friendliness of a levee, the Andong River Experiment Center applied a biopolymer, which is a new eco-friendly substance, to fabricate a levee model, and conducted a hydraulic model experiment to evaluate the reliability and stability of the new type of levee. An image analysis was applied to calculate the scale of the breaches of the levee slopes. Based on the experimental results obtained, the characteristics of the breach between an earthen levee and the proposed levee were compared. The stability of the levee body was also evaluated according to the thickness of the new substance. The ultimate aim of this study was to derive the optimal conditions by verifying the performance and effectiveness of the new substance in terms of levee breach factors such as overflow, seepage, or piping in a series of hydraulic experiments. In the future, the field application of these optimal conditions will be verified through a real-scale experiment.

Purpose - An increasing number of retailers and manufacturers are relying on sales promotions to boost sales, extend market share, and clear excess inventory. Previous research on sales promotions primarily focus on the effect of this approach on two main perspectives: firm level, which includes sales, market share, and firm performance; and customer level, which involves perceived quality of product/service, change in reference price, and purchase/repurchase intention. To help subsequent and new research on these issues, this research note focuses on finding patterns of sales promotions conducted in various sectors of industry in the Korean market. Methodology - A survey on the sales promotion usage pattern of a company was conducted with 74 decision makers in various companies followed by a small group interview. Findings- Results indicated that price off and bonus pack sales promotions were the main types of sales promotions conducted and considered in most sectors of industry in Korea. Decision makers were also found to have knowledge on the long-term disadvantage of sales promotions. Despite this advantage, two main reasons were pointed out for the continuing conduct of sales promotions: reaction to the sales promotions of competitors and expectation of other members of the organizations. Conclusion- This research on the usage pattern of sales promotions in Korea can contribute to the choice of the next sales promotion research topic in Korea and in other nations.

Ko, D.; Kang, J., and Ryu, Y., 2019. Experimental study on relation between breach process and velocity distribution on levee due to overflow. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 16-20. Coconut Creek (Florida), ISSN 0749-0208.Coastal levee is an defensive structures important in low-lying coastal areas prone to floods, but is vulnerable to overflows when water levels increase extremely. Due to storm surge and high waves, water overflow and wave overtopping occur over coastal levee. Likewise, river levee is to protect lowland areas from floods. However, levee breaches due to aging of levees have caused huge damages on properties and human casualties. To advance as a society, it is essential to pursue meaningful implementations of solutions that prevent the erosion of levees during floods. To find a resilient structure of levee against overflow, this study has tested an environmentally friendly substance for reinforcing levee. With intent to testify the new method, a series of hydraulic experiments were carried out for to verify a flow state and surface velocity distribution according to levee breach progress by building a semi-prototype levee with a bottom width of 5 m, a slope of 1:2, a crown width of 1 m, and a height of 1 m in a 3 m bottom-wide natural channel. By building a measuring system using a number of imaging devices on site, the surface velocity distributions on the earthen levee and the levee reinforced with the new environmentally friendly substance were measured using a LSPIV technique. It is expected to be able to examine the characteristics of flow velocity distribution following breach processes on levees to evaluate the initial points of failure and the weak points during overflow.

This study was carried out to investigate the possibility of using basalt powder sludge instead of sand in a normal cement dry mortar as a way to recycle basalt powder sludge, which is a waste product from the manufacturing a process of basalt in Jeju. Basic performance evaluations of the dry mortar material included a compressive strength test, a flexural strength test, and SEM to observe the micro structure. The compressive and flexural strengths were increased to a replacement ratio of 21% of basalt powder sludge, whereby a strength enhancement of about 40% greater than that of normal dry mortar was shown. However, the creation of hydration products affected the replacement ratio of the basalt powder sludge. The possibility of using basalt powder sludge waste was identified in this study, and results showed that the basalt powder sludge waste could be used as a material for a secondary product of concrete.

When recycled aggregate with old mortar and particles is used in concrete mixing, such aggregates can affect hydration reaction by promoting or inhibiting it. In this study, the possibility of hydration reaction on old mortar and particle was analyzed. Hydration reaction was carried out in old mortar that is finely crushed by an impact machine in the production of recycled aggregates, and it was found that this did have an impact on the strength development of concrete. Unlike in old cement, the hydration reaction did not progress in the particles, and it had high amounts of silica powder and calcium carbonate. In conclusion, the old mortar can have the influence of improving compressive strength, but the particles can delay the setting time of recycled aggregate concrete.

We examined the effect of shared decision-making (SDM) on women&rsquo, s adherence to breast and cervical cancer screenings and estimated the prevalence and adherence rate of screenings. The study used a descriptive cross-sectional design using the 2017 Health Information National Trends Survey (HINTS) data collected by the National Cancer Institute. Adherence was defined based on the guidelines from the American Cancer Society and the composite measure of shared decision-making was constructed using three items in the data. Multivariable logistic regression was performed to examine the association between the SDM and adherence, controlling for cancer beliefs and socio-demographic variables. The analysis included 742 responses. Weighted to represent the U.S. population, 68.1% adhered to both breast and cervical cancer screening guidelines. The composite measure of SDM was reliable (&alpha, = 0.85), and a higher SDM score was associated with women&rsquo, s screening adherence (b = 0.17, p = 0.009). There were still women who did not receive cancer screenings as recommended. The results suggest that the use of the SDM approach for healthcare professionals&rsquo, communication with patients can improve screening adherence.

Previous studies have shown that Medicare beneficiaries do not tend to switch their prescription drug plans (Part D), even though they can greatly save on the money spent on drugs by switching plans. To explore this occurrence, the present study focused on the concept of social exclusion&mdash, one of the most important characteristics prevalent in the elderly. This study compared the impact of two types of social exclusion on the association between psychological cost and plan switching: active (or rejected) social exclusion and passive (or ignored) social exclusion. The study&rsquo, s aim was to examine the moderating effect of social exclusion on the relationship between the cost of switching and willingness to switch plan to build sustainable health care system. The Prescription Drug Study supplementary to the Health and Retirement Study (HRS) data were utilized for analysis by applying a Hierarchical Linear Model (HLM) (N = 1042). The findings suggest that active social exclusion moderates the relationship between the switching cost and willingness to switch plan. This study&rsquo, s findings will help policymakers better understand the elderly&rsquo, s decision-making process pertaining to plans and promote their informed plan decisions to build sustainable health care system.

The reasons why levee breaches during floods are largely due to overtopping, seepage, and structurally induced piping. According to an analysis of domestic and overseas reported cases of levee breaches, overtopping was found to be the cause for approximately 40% of all cases of breach. Despite such efforts of previous research to establish disaster prevention plans associated with levee breaches, to enhance our understanding of the processes and reasons, further research regarding the prediction of levee breaches must be undertaken by accumulating test data under several different conditions and further verification of the data using numerical models must also be undertaken. In this study, development of technologies regarding a new environmentally friendly bio-polymer capable of protecting levees from erosion is being undertaken. Breach mechanisms was assessed using an image measurement system that collected data regarding the breach progress of the levee, close-up views of the breaching surface, and the formation of the final breaching cross-sections. Further, levee slopes were covered with a bio-soil mixed with a new substance for the purpose of analyzing the stability and the time delay effect.

Vegetation is one of the key factors in river management where environmental aspects as well as flood protection should be taken into consideration. Because of this, numerous studies have been done including experiments and hydrodynamic modelling. Because most of experimental studies were made in indoor laboratory flumes with artificial trees, there are still limitations in transfer of their result to actual channels. REC (River Experiment Center) of Korea has been operating three real-scale, nature-like outdoor experimental channels. In a straight channel, several 4x2 m actual willow patches were planted and have been grown last three years for studies on flow vegetation interaction. A set of intensive flow measurement was made around the first upstream willow patch using ADVs together with measurement of vegetation properties. The experiments were made under several different depth conditions simulating snow-melt and flash-flood. Distribution of flow around and through the patch was characterized along with vertical profiles. The results of the experiment enhance understanding on interaction of flow and actual vegetation in a natural channel and may also provide information on flow resistance used for hydrodynamic modelling and validation.