The rise of the sharing economy is transforming the tourism and hospitality industry (So, Oh, and Min, 2018; Zhu, So, and Hudson, 2017). The growing popularity of Airbnb has led a number of recent studies to investigate consumer value derived from such innovative consumption model. In the context of Airbnb, research shows that perceived value motivated travelers to choose Airbnb (Mao & Lyu, 2017). However, the theoretical construct of consumer value includes multiple dimensions, such as emotional value, social value, price value, and quality value, and how each dimension contributes to consumer attitudes and behavioral intentions toward Airbnb is unexplored. Therefore, this study sets forth a national field investigation to provide a holistic understanding of consumer evaluation of various value dimensions with respect to Airbnb experiences. To empirically test the proposed model, a quantitative, national online survey was conducted using Qualtrics Online Sample. After checking the performance of the measurement model, we evaluated the results of the structural model. The results show that emotional value and quality value significantly explain overall attitude toward Airbnb, whereas, price value and social value were not significant in predicting attitude. However, price value and social value, together with overall attitude, significantly explain consumer’s purchase intention. The results show that the t values from bootstrapping were greater than 1.96, and the R2 values for endogenous variables well exceeded .26. All exogenous constructs producing effect sizes ranging from small to large. In addition, the Q2 for the endogenous latent constructs were well above the threshold, with .421 for overall attitude and .472 for behavioral intentions, thereby substantiating the structural soundness of the proposed model.

The hotel industry has been reaching their existing and prospecting customers via emails throughout a customer’s journey, from pre-arrival information/promotions to post-stay emails for the reviews (Huang, 2016). In different from other email marketing campaigns containing pure promotional materials for acquiring customers, post-stay e-mails can be used to send personalized messages and build an emotional connection with customers by thanking and rewarding their stays. As an increasing number of customers open and read emails via mobile devices on the move (Jordan, 2015), effectively designed post-stay emails with persuasive messages can be a powerful communicating method keeping customers in the lines of dialog with the brands. However, there is lack of studies on how the post-stay email marketing campaign works to retain customers. This study aimed to identify post-stay email features that affect customers’ intention to revisit the same hotel brand depending on their levels of involvement in choosing hotels for leisure purpose. Grounded on the Elaboration Likelihood Model (ELM) (Petty & Cacioppo, 1986), this study identified what causes “motivation” to process a post-stay email and which email features can be more effectively positioned to persuade consumers with different elaboration levels. This study developed hypotheses regarding the effects of email features on attitude and intention to revisit the hotel brands. A total of 189 responses was determined to be usable in this study. Using Path Analysis, this study tested multivariate regression model with direct effect of email features on attitude and indirect effects of email features on intention to revisit the hotel brand. In addition, this study tested a moderating effect of leisure involvement on the hypothesized paths. The results showed that consumers with a low level of leisure involvement tended to be influenced by financial and interactivity features on their attitude towards the hotel brand while personalization features yielded favorable attitude towards the hotel brand for consumers with a high level of leisure involvement. Attitude towards the hotel brand was a significant predictor of behavioral intention to revisit the hotel brand that sends post-stay emails in this study. Industry professionals and researchers can utilize this study to better design their e-mails as customer retention strategies. The email features analyzed in this study can be strategically included in the post-stay e-mail according to their target market. The initiative can assist in reinforcing or persuading their guests to revisit the hotel brand and build stronger customer relationships.

This paper develops a conceptual model of international social media marketing strategy that describes how culture shapes consumers’ use of social media around the world. Drawing from cultural psychology, marketing, and computer information systems, we use Kietzmann et al.’s (2011) functional building blocks of social media to organize social media functions, then explicate how various dimensions of culture affect the way such social media functions are used across cultures. By delineating these complex relationships, our model and the propositions that stem from it offer directions for future research and advance understanding of cross-cultural differences with implications for businesses that provide social media or capitalize on social media for global reach in the international marketplace.

Clithon retropictus has been protected by the Ministry of Environment as an endangered species since 1998 and has been listed on the state red list of endangered species category II. It is viewed as a representative for all endangered species in the northeastern coastal waters of Korea. Most of the habitats of C. retropictus have been found to be in an unstable state because of development projects such as road construction, small stream development, irrigation for securing agricultural water, and flood prevention. These habitats are damaged by small stream maintenance projects and development, and the risk of damage is increasing and active efforts are needed in order to protect them. Although the Ministry of Environment is striving to preserve this endangered species, the habitat of C. retropictus is still facing external threats because it spreads to only a small area at high densities. Therefore, in order to protect the habitat of C. retropictus, a level II endangered species, it is urgent to make an effort to minimize habitat damage and to take measures for its protection.

Nonthermal atmospheric plasma has been studied for its many biomedical effects, such as tooth bleaching, wound healing, and coagulation. In this study, the effects of dentinal tubules occlusion were investigated using fluoride-carboxymethyl cellulose (F-CMC) gel, nano-sized hydroxyapatite (n-HA), and nonthermal atmospheric plasma. Human dentin specimens were divided to 5 groups (group C, HA, HAF, HAP, and HAFP). Group HA was treated with n-HA, group HAF was treated with n-HA after a F-CMC gel application, group HAP was treated with n-HA after a plasma treatment and group HAFP was treated with n-HA after a plasma and F-CMC gel treatment. The occlusion of dentinal tubules was investigated using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS), which shows Ca/P ratio. In the EDS results, a higher Ca/P ratio was shown in the groups including n-HA than in the control group. The specimens of group HAP and HAFP had a higher Ca/P ratio in retentivity. In the SEM results, there was not a significant difference in the amount of times applied. Therefore, this study suggests F-CMC gel and n-HA treatment using nonthermal atmospheric plasma will be a new treatment method for decreasing hypersensitivity.

Codium fragile (Suringar) Hariot is an edible green seaweed that belong to the Codiaceae family and has been used in Oriental medicine for the treatment of enterobiasis, dropsy, and dysuria. Methanol extract of codium fragile has anti-oxidant, anti-inflammatory and anti-cancer properties, although the anti-cancer effect on oral cancer has not yet been reported. In this study, we investigated the anti-cancer activity and the mechanism of cell death by methanol extracts of Codium fragile (MeCF) on human FaDu hypopharyngeal squamous carcinoma cells. Our data showed that MeCF inhibits cell viability in a dose-dependent manner, and markedly induced apoptosis, as determined by the MTT assay, Live/Dead assay, and DAPI stain. In addition, MeCF induced the proteolytic cleavage of procaspase -3, -7, -9 and poly(ADP-ribose) polymerase(PARP), and upregulated or downregulated the expression of mitochondrial-apoptosis factor, Bax(pro-apoptotic factor), and Bcl-2(anti-apoptotic factor), . Futhermore, MeCF induced a cell cycle arrest at the G1/S phase through suppressing the expression of the cell cycle cascade proteins, p21, CDK4, CyclinD1, and phospho-Rb. Taken together, these results indicated that MeCF inhibits cell growth, and this inhibition is mediated by caspase- and mitochondrial-dependent apoptotic pathways through cell cycle arrest at the G1/S phase in human FaDu hypopharyngeal squamous carcinoma cells. Therefore, methanol extracts of Codium fragile can be provided as a novel chemotherapeutic drug due to its growth inhibition effects and induction of apoptosis in human oral cancer cells.

우리는 게임 렌더링을 위해 파스텔 드로잉 효과를 시뮬레이션 하는 회선기반 방법을 제안한다. 연구 동기는 굵고 진한 스트로크 패턴, 문지르기 효과, 스트로크 겹침 등 파스텔 드로잉의 속성을 모방하는 것이다. 굵고 진한 파스텔 스트로크 패턴을 위해 우리는 직사각형 모양의 스트로크 패턴과 유사한 굵은 노이즈를 사용한다. 문지르기 효과는 노이즈를 두 단계로 적분하는 회선 모델을 제안한다: 첫 단계로 회선 방향에 수직한 노이즈를 적분하고, 이를 두 번째 단계에서 회선 방향으로 적분한다. 스트로크 겹침 효과를 구현하기 위해 우리는 누적 노이즈 필드(ANF, accumulated noise field)를 제안한다. 이는 각 레이어에 노이즈가 분포되어 있다고 가정하고, 서로 다른 레이어에 있는 스트로크 패턴의 색을 섞는 모델을 의미한다. 이러한 세 가지 개념은 회선기반 프레임 웍으로 통합되며 시각적으로 만족스러운 게임 장면의 파스텔 드로잉 효과를 보인다.

픽셀 아트는 낮은 해상도와 제한된 색 팔레트를 가지고 영상을 표현한다. 픽셀 아트는 낮은 연 산 성능과 적은 저장 공간을 가지는 초기 컴퓨터 게임에서 주로 사용되었다. 현대에 이르러, 픽셀 아트는 예술이나 퍼즐, 게임과 같은 다양한 분야에서 찾아볼 수 있게 되었다. 본 논문에서는 게임 캐릭터 영상을 입력으로 받는 픽셀 아트 생성 모델을 제안한다. 기존 방법 과는 달리, 합성곱 신경망(CNN:Convolutional-Neural Network)를 픽셀 아트 생성 목적에 맞게 변형하여 이를 이용하는 방법을 제시한다. 기존의 합성곱 연산 후에 upsampling 과정을 추가하여 픽셀 아트가 생성될 수 있도록 하였다. 네트워크는 ground truth와 생성된 픽셀 아트와의 평균 오차 제곱(MSE:Mean Squared Error)을 최소화해나가며 학습을 수행한다. Ground truth는 실제 아티스트가 생성하도록 하였고, 이미지 회전과 반전 기법을 이용하여 augumentation을 수행하였다. 생성된 데이터 집합은 학습, 검증, 시험 데이터로 나누었다. 이러한 데이터 집합을 기반으로 감독 학습을 실시하여 픽셀 아트 생성 네트워크를 학습하였다. 학습 모델의 학습 과정과 학습 정확도를 제시하고, 시험 데이터 뿐만 아니라 다양한 영상에 대한 픽셀 아트 결과도 함께 제시한다.

Cumulative effects are defined as the joint and aggregated effects of many factors and processes. Their consideration in landscape and environmental assessments are integral at both the project and strategic level, and they can help to bridge the different spatial and temporal scales. The primary challenge of conducting cumulative effect assessments (CEAs) is the difficulty in understanding the complicated nature of cumulative effects. We used three criteria for a systematic understanding of the barriers to addressing cumulative effects that are critical for improving knowledge systems for sustainable development and environmental assessment: salience, credibility, and legitimacy, and analyzed three cases through a variety of studies and resources: the Middle Humber in the U.K., the Transboundary Crown of the Continent in the U.S. and Canada, and the Great Sandhills in Canada, to understand how CEAs have been applied and obstructed in terms of the three criteria. In addition, a series of focus group interviews with experts and practitioners were performed to illuminate the critical barriers based on the criteria for addressing CEA in the context of South Korea. Based on the lessons, we suggest several key strategies such as securing a cooperative consulting process, and active and transparent partnerships; using a strategic environmental assessment as a framework; understanding and incorporating stakeholder knowledge; using advanced computer modeling and simulation techniques including effective visualization tools; and preparing a simple model design and understandable scientific information.

In this review, we have tried to summarize the evidence and molecular characterization indicating that 20α-hydroxysteroid dehydrogenase (20α-HSD) is a group of the aldo-keto reductase (AKR) family, and it plays roles in the modulation and regulation of steroid hormones. This enzyme plays a critical role in the regulation of luteal function in female mammals. We have studied the molecular expression and regulation of 20α-HSD in cows, pigs, deer, and monkeys. The specific antibody against bovine 20α-HSD was generated in a rabbit immunized with the purified recombinant protein. The mRNA expression levels increased gradually throughout the estrous cycle, the highest being in the corpus luteum (CL) 1 stage. The mRNA was also specifically detected in the placental and ovarian tissues during pregnancy. The 20α-HSD protein was intensively localized in the large luteal cells and placental cytotrophoblast villus, glandular epithelial cells of the endometrium, syncytiotrophoblast of the placenta, the isthmus cells of the oviduct, and the basal part of the primary chorionic villi and chorionic stem villus of the placenta and large luteal cells of the CL in many mammalian species. Further studies are needed to determine the functional significance of the 20α- HSD molecule during ovulation, pregnancy, and parturition. This article will review how fundamental information of these enzymes can be exploited for a better understanding of the reproductive organs during ovulation and pregnancy.

In the United States and Europe, new environmentally friendly asphalt pavement has been researched as an alternative to traditional hot asphalt pavement. After the Paris Convention of 2015, policies should be found to reduce carbon dioxide. In the field of asphalt pavement, new methods are needed to reduce carbon dioxide from the traditional hot asphalt pavement. In Korea, waste asphalt is growing and natural aggregate is running dry. So the government is implementing policies to increase the use of waste resources. So, it created a new asphalt pavement method to reduce CO2 and use waste asphalt. It is a cold recycled asphalt pavement. Emulsified asphalt has a balance of dispersibility, stability, and adhesive between water, aggregates, and asphalt. But, the physical properties of emulsified asphalt can be degraded compared to traditional hot asphalt pavement. So there are limitations in actual use. The study compared the softening point, elastic recovery, and penetration properties of asphalt mix compounds by using latex in emulsified asphalt. In particular, cations latex was used for the emulsified asphalt, which could further improve the physical properties.

Roller Compacted Concrete Pavement (RCCP) is a pavement placed and compacted using an asphalt paver and a compaction roller by applying a small amount of concrete mixture and shows excellent structural performance as a result of hydration reaction of cement and interlocking of aggregates by roller compaction. It also provides economic advantages over conventional concrete pavements by reducing unit cement content and construction period, simplifying construction process, and decreasing traffic closure time (Wayne, 2006). However, given that it tends to show lower IRI levels than common concrete pavements since its low unit water content and binder weight ratios make uniform quality control difficult and roller compaction after paving makes the surface irregular and rough, with rough profile at the bottom of the pavement being reflected on the surface, RCCP is used mainly in port and industrial roads for low speed (60km/h or less) traffic (Dale Harringtion, 2010; Gregory, 2009). In order to apply RCCP to high-speed roadways, diamond grinding (DG) or asphalt overlay that is highly effective in improving roughness is needed (Fares Abdo, 2014; Gregory, 2009). Applying DG over RCCP leads to excellent skid resistance and noise reduction effects as a great percentage of aggregates makes the pavement surface rough, enhancing durability of concrete and the life of DG functionality. In addition, RCCP can be used as a high performance base layer of composite pavements, as it can reduce reflecting cracking at joints and cracked sections thanks to early strength development and low drying shrinkage of concrete. In this study, we assessed longitudinal roughness improvement effects by roughness-affecting factor by applying DG methods and asphalt overlays to three RCCP sites with a variety of sub-structural conditions and analyzed the effects on roughness of existing RCC pavements depending on surfacing method (DG, APOverlay).

Roads in Korea are equipped with PMS (Pavement Management System) computation data that runs on highway, national highway and municipal road. PMS is a program that selects and manages the road pavement optimal maintenance alternative as a indicator of the road pavement structural and functional performance. PMS is a system that has been developed for the primary purpose of maintaining the structural performance of road pavement, and so far does not include any indicators associated with the safety of road users. However, the road cave-in, which have recently become an issue on social networking sites, mass-media, and other issues, should pose systematically because it can make a safety risk to road users, and in particular lead to the structural and functional failure of the PMS program in view of the road pavement. Accordingly, this research has developed a practical use case for developing an integrated road cave-in management program based on the results of various studies on the exploration, analysis, assessment and handling of the existing road cave-in in Korea.

The composition of the deicer sprayed on the highway is spreading over the highway by the scattering or snow removal activity, or car movement and consequently affecting the vegetation environment around the highway. These are the cause of the damage of fruit trees and crops, and also the cause of corrosion of highway structures. The goal of this study is to estimate the detected range of deicer components from a highway. The concentration of the deicer components in gauze and soil were investigated according to the crossing distance from the highway. The data collected were then used to estimate the concentration range of deicer components in a rage of distance up to 100 m from the highway where the deicer was spread. The sample time and weight of gauze were measured before and after installation, and the soil was collected at more than three points in parallel with the highway at the gauze installation point. The components in gauze and soil were investigated in addition to the deicer components (Ca2+, Na+, Cl-) as well as Mg2+ and K+. As Ca2+ and Cl- components of deicer were affected by agricultural use, Na+ component was selected as a tracer and further SAR (Sodium Adsorption Ratio) of soil was analyzed to examine the degree of influence on vegetation indirectly. The gauze concentration was evaluated by the concentration of the deicer ingredient at the background concentration of the blank gauze. The total amount of the deicer sprayed in the study road for 4 months (winter season) was about 93 ton/km. In the gauze test, the spread of the deicer was detected at a distance of 100 m in study area, but the concentration of the deicer in the gauze by distance decreased rapidly within 10 m from the highway. And concentration of the deicer components in gauze and soil came down after rainy season (August ~ Sep.). The results showed that the components of the deicer could be spread widely by the wind. The effective range of the deicer on vegetation based on SAR in soil was estimated to be less than 20 m from the highway. This study examines the concentration changes of the deicer components in gauze and soils and shows that deicer components sprayed on the highway are accumulated and moved over time by wind, snow removal, terrain, water system and land use around the highway.

Domestic continuously reinforced concrete pavement has been built on a large scale on the Jungbu Expressway, which opened in 1987. Since then, there have been few application due to cost and construction difficulty. Currently, most of the expressway concrete pavements have been applied with jointed plain concrete pavement, but the interest in continuously reinforced concrete pavement has been increasing recently due to frequent premature failure in joints of JPCP. Accordingly, Korea Expressway Corporation has established design guidelines and details for continuously reinforced concrete pavements for expressway in 2014, based on the design method applied to the Jungbu Expressway, but incorporating foreign useful design methods. In terms of construction, pilot constructions were performed on Pyeongtaek~Jecheon Expressway Construction. The new design guidelines were applied to some sections of the Sangju~Yeongdeok Expressway Construction Project in 2016. This study conducted a survey and analysis of transverse cracks for one year after continuously reinforced concrete pavement construction in Sangju~Yeongdeok Expressway. This route was constructed with pavement thickness, base layer and longitudinal reinforcement according to domestic design guidelines. However, the transverse reinforcement was arranged differently according to the section. After construction, the transverse crack spacing was surveyed and the crack gauges were installed at the crack position to measure the movement. This compares the crack spacing according to the characteristics of longitudinal reinforcement and observes continuous movement of the crack width. The results showed that the crack spacing was more affected by the climate at the time of construction than the arrangement method of the transverse reinforcement. The crack width showed periodic changes according to the temperature change over 24 hours. However, due to seasonal changes, it showed a tendency of gradual increasing or decreasing in crack widths, and it was predicted that different measurement results will be shown depending on the time of crack width measurement. Generally, it is predicted that the crack spacing will be narrowed and the crack movement will tend to converge with the period after construction. This initial crack movement data is expected to be useful for comparing whether these predictions are valid.

In recent years, there have been applied methods for minimizing noise by adjusting the method of installing soundproof walls, soundproof tunnels, soundproofing rims, environmental facilities, etc., and the shape of the surface texture of tire treads and packaging materials for the purpose of reducing road noise. Low noise pavement methods such as rubber asphalt (CRM), open graded asphalt concrete (OGAC), permeable Friction Courses (PFC), open graded friction courses (OGFC) and porous asphalt have been applied to reduce road noise. Especially, porous pavement is the most widely used low noise pavement with porous structure, which can reduce noise and drain water through continuous void of pavement. On the other hand, porous asphalt pavement has problems such as reduction of noise reduction effect and difficulty of road surface management due to void closing and increase of construction cost. The purpose of this study is to develop ultra-thin layer hot mix asphalt pavement method which maximizes road noise reduction effect by surface micro voids (Recover asphalt pavement) to improve void clogging of present porous pavement method. For this study, maximum size 5mm aggregate and cationic-treated fiber reinforced asphalt modifier (CSM) were used. The Marshall design method was applied grain-size distribution curve was based on SMA mix design. Marshall test, TSR, MMLS3 test and Hamburg test were carried out to evaluate the mechanical properties of ultra -thin layered asphalt pavement method with surface micro voids. Also, the effect of road noise reduction was evaluated through field application in urban area.

Edible biopolymer films were developed from the exopolysaccharides (EPS) extracted from Weissella confusa 113-2. The optimum composition for film formation was determined using the response surface analysis with the explanatory variables of the EPS (0.5-5.5%) and glycerol (0.5-5.5%) concentrations and the response variable of film elastic modulus (EM). The mass ratio of distilled water to solids was set constant (14:1). Tensile strength (TS), percentage elongation at break (%E), EM, water vapor permeability (WVP) of EPS films were evaluated. The glass transition temperatures of the films were also determined by a dynamic mechanical analysis. The optimum mass ratio of EPS to glycerol was 0.754:0.375. The WVP, TS, %E, and EM of the film under the optimal composition were 3.53±0.21 g·mm/kPa·h·m2, 7.03±0.49 MPa, 84.82±12.31%, and 62.03±6.93 MPa, respectively. The glass transition temperature varied from 54 to 83 °C. The EPS film has the potential to be applied to food products as an edible film with physical and barrier properties comparable to other biopolymer edible films.

Magnetic resonance imaging (MRI) technique has recently been applied in agriculture and food science. It has potential to visualize internal structure of foods in nondestructive way and provides spatial information which could make reconstruct of three-dimension. MRI system also has great advantage for tracking water in beans or seeds. This study intends to analyze the changes of water distribution of coffee beans during water up-taking process. Samples used in the experiment were ‘Robusta’ coffee beans (Vietnam G1, Scr18 polish). A 30mm diameter plastic disposable test tube was used to hold bean during water up-take process. The oil column was placed next to the tube to get and to use as a reference signal. The magnetic resonance imaging system which installed at Institution for Agricultural Machinery & ICT Convergence in Chonbuk National University was used to obtain magnetic resonance (MR) image data sets. 30 images are included in each image data sets with ‘Axial’ image plane direction. In experiment, we used ‘Gradient Echo 3D’ pulse sequence. The water uptake process was performed for 150 minutes and acquired image data sets in every 10 minutes. This study showed some coffee beans which extracted as region of interest (ROI) from each images to study the water uptake process.