With the development of information technology, online food delivery services have significantly changed people’s food consumption patterns. The outbreak of COVID-19 has further facilitated the development due to restaurant restrictions and social distancing measures. Due to the emergence of online food delivery services, scholars have paid increasing attention to this popular topic, and a large number of studies have examined which factors are related to consumers’ intention to use online food delivery services. However, previous studies showed inconsistent findings, and relationships between variables lack a comprehensive understanding. Therefore, this study aimed to develop a research model and examine the factors influencing consumers’ intention to use online food delivery services. By reviewing and analyzing 52 studies with 53 independent samples (N = 22,937), the meta-analytic structural equation modeling approach was carried out to assess the research model. The findings indicate that two attributes of online food delivery services (i.e., convenience and price-saving orientation) play different roles in the research model. Specifically, convenience significantly impacted perceived ease of use but had no direct impact on perceived usefulness. Price-saving orientation significantly influenced both perceived ease of use and perceived usefulness. Moreover, relationships between perceived ease of use, perceived usefulness, and perceived trust were significant, and these factors ultimately significantly led to the intention to use food delivery services. The findings contribute to theoretical advancement in the extant literature on food delivery services and help firms develop to provide better food delivery services for consumers’ continuous usage.

Damages by jellyfish are occurring frequently around the world. Among them, accidents caused by jellyfish stings are serious enough to cause death. So we designed a jellyfish blocking net and analyzed its stability to prevent sting caused by jellyfish entering the beach. To this end, the dynamic behavior of the jellyfish blocking net according to the current speed (0.25-1.0 m/s) and the net type (50, 100 and 150 mm) on the upper part of the blocking net was modeled using the mass spring model. As a result of simulations for the model, the horizontal tension (horizontal component of the mooring tension) of the mooring line increased with the decrease in the mesh size on the upper part of the blocking net at all current speeds, but exceeded the holding force at high tides faster than 0.5 m/s and exceeded the holding force at all current speeds at low tide. Therefore, the jellyfish blocking nets showed poor stability overall. The depth of the float line had a little difference according to the upper mesh size and increased lineary proportional to the current speed. However, the float line sank too much to block the incoming jellyfish. These analysis results helped us find ways to improve the stability of the jellyfish blocking net, such as adjusting the length of the mooring line and improving the holding power. Therefore, it is expected that this technology will be applied us various underwater structures to discover the weaknesses of the structures and contribute to increasing the stability in the future.

The design and analysis of the rigidity and deformation of the vehicle body are basically performed in two forms. First, the relative response of components separated from a parent system or connected as a model of a subsystem is examined. Second, the entire model is used to consider the absolute response of the components to the externally transmitted vehicle service load, which is defined as that of the entire vehicle body system. In this paper, we propose the finite element modeling for the structural design of the car body. First, we will explain the simple finite element modeling of the car body, explain the method of formulating the stiffness of the joint, and finally the shell element. The proposed finite element modeling is proposed. By applying the proposal, it is possible to propose finite element modeling of all medium and large passenger cars less than 3 tons.

Rotor disc (로터 디스크)는 중대형 유조선에서 유류를 하역하는 장치인 COPT (Cargo Oil Pump Turbine)의 터빈을 고속으로 회전시키는 핵심 부품이다. 이 rotor disc는 중심 shaft에 여러 개의 turbine을 원주상으로 배열하고 체결하여 제작한다. 현재의 제작 방법으로는 turbine blade를 배열하고 shroud 덮개로 연결하여 riveting 방식으로 체결한다. 이런 고전적인 방법은 blade pitch의 불균일은 물론 작업 시 오류로 인해 blade에 손상이 가는 경우가 있다. 이러한 단점을 해결하기 위해서는 조립식의 rotor disc를 설계하여 제작방식을 변경해야 한다. 설계뿐만 아니라 조립식의 disc가 구조적으로 안정한지를 평가해야 한다. 본 논문은 blade의 설계와 이를 조립하였을 때에 구조안전성을 평가하기 위해 구조 해석하여 그 안전성을 검증 한다.

본 논문에서는 온실 구조물의 구조 성능 검토 시 적합한 모델링 방법을 제시하기 위해 대상 온실 구조물을 선정하고 지점 및 접합부 조건 그리고 케이블 요소의 단면적을 변화시켜 가며 파라메트릭 스터디를 수행하였으며, 이들 파라메터의 변화에 따른 대상 구조물의 주요 모드 형상 및 고유진동수 변화를 조사하였다. 또한 대상 구조물에 대해 현장 가속도계 측정법을 이 용하여 상시진동을 계측하여 주요 모드 형상 및 고유진동수를 측정하여 해석 결과와 비교하였다. 이들 비교 결과로부터 대 상 온실 구조물의 해석에 적합한 모델링 기법을 제시하였다.

In this study, a shape design and an analysis considering structural stability were investigated to develop an icosahedron-based hemispherical modular dome. To design this modular dome, a program that can perform icosahedron shape modeling, modularization of joint connection members, and the analysis of structural stability was developed. Furthermore, based on the adopted numerical model, the eigen buckling mode, unstable behavior characteristics according to load vector, and the critical buckling load of the modular dome under uniformly distributed load and concentrated load were analyzed, and the resistance capacities of the structure according to different load vectors were compared. The analysis results for the modular dome suggest that the developed program can perform joint modeling for shape design as well as modular member design, and adequately expressed the nonlinear behaviors of structured according to load conditions. The critical buckling load results also correctly reflected the characteristics of the load conditions. The uniformly distributed load was more advantageous to the structural stability than concentrated load.

The research is a correlational study to look for causes and factors relating to the design of written documents (professional reading materials) and identify those relationships that are useful for communication designers. The research specifically targeted the relationships between perception and reader’s past experiences and appearance of the written documents. A preliminary survey, such as interviews, discussions, questionnaires and brainstorming sessions are conducted to establish the observable attributes related to perception which are reader’s interests, importance of information and written documents complexity. Finally, the research used Structural Equation Model (SEM) to identify significant differences and analyze strong and weak correlations between these attributes. In general, the results of the study shows that the attribute appearances of a written documents with excellent visualizations for information display shows a strong correlation with interests while the attributes importance is weakly correlated with the complexity of the documents.

A standard RC apartment structure was analysed using commercial structural analysis program MIDAS. The effects of TLD were considered by equivalent tuned mass damper model and harmonic load of wmch frequency was identical to that of the RC structure and artificial earthquake loads generated accroding to the design spectrum in KBC2005 were used as excitation loads. TLD showed maximally 70% reduction of peak/RMS relative displacement, interstory drift, acceleration, and story shear induced by harmonic load while it reduced about 20~28% of those structural responses excluding absolute acceleration induced by artificial earthquake loads.

본 논문에서는 유연한 철제와 목조 지붕구조체를 가진 1/2 축소 전단벽 건물의 진동대 실험결과를 이용한 성공적인 구조물의 재해석과 선형ㆍ비선형 동적특성을 연구하기 위한 해석모델링 방법에 대해서 연구하였다. 대상 건물은 유연한 지붕구조체와 4개의 보강조적조 전단벽으로 구성되어 있다. 유연한 지붕구조체의 동적특성 때문에 다자유도 모델을 사용하였으며, 다수의 선형 및 비선형 동적해석을 실행하기 위하여 구조물의 자유도를 단순화하였다. 각각의 구조부재의 이력특성과 재료특성 그리고 동적해석을 수행하기 위한 주요 구조변수의 적절한 설정 방법에 대하여 고찰하였다.

This study aims to analyze the causality of placeness cognition which includes the place satisfaction, place attachment, place function, and behavioral intention of those who visit Suseong amusement park. A questionnaire survey was administered to 255 individuals who visited in Suseong amusement park. To conduct the analysis, six hypotheses were formulated and tested. While two hypotheses were statistically rejected, four hypotheses were accepted. First, place satisfaction was found to have a positive effect on place function (β=.577, p<0.001). Second, place attachment had a positive effect on behavioral intention (β=.450, p<0.001). Third, place function had a positive effect on behavioral intention (β=.247, p<0.05). Fourth, place function was found to have a positive effect on place attachment (β=.637, p<0.001). Unlike most existing research which has indicated that place satisfaction has a direct effect on behavioral intention this study suggests a that double mediating effect through place function and place attachment between place satisfaction and behavioral intention. In addition to increasing satisfaction through the environment of the Suseong Amusement Park, it is also necessary to improve the function of the place to ensure repeated visits from visitors.

Purpose - This study provides appropriate procedures for EFA to help researchers conduct empirical studies by using PLS-SEM. Research design, data, and methodology - This study addresses the absolute and relative sample size criteria, sampling adequacy, factor extraction models, factor rotation methods, the criterion for the number of factors to retain, interpretation of results, and reporting information. Results - The factor analysis procedure for PLS-SEM consists of the following five stages. First, it is important to look at whether both the Bartlett test of sphericity and the KMO MSA meet the qualitative criteria. Second, PAF is a better choice of methodology. Third, an oblique technique is a suitable method for PLS-SEM. Fourth, a combined approach is strongly recommended to factor retention. PA should be used at the onset. Next, it is recommended using the K1 criterion. In addition, it is necessary to extract factors that increase the total variance explanatory power through the PVA-FS. Finally, it is appropriate to select an item with a factor loading into 0.5 or higher and a communality of 0.5. Conclusions - It is expected that the accurate factor analysis processed for PLS-SEM as previously presented will help us extract more precise factors of the structural model.

In this study, we propose a structural modeling method to analyze the seismic behavior characteristics of arched stone bridge. For this purpose, we select the representative model of arched stone bridge, and various arch types are set in consideration of the width and height. Accordingly, this study applies the discrete element method for the modelling of discontinuum structure to analyze the seismic behavior characteristics according to the various arched types.

Based on the study of LOD for BIM when doing structural modeling. Divide and standards LOD criteria And investigates the characteristics of property which have to involve in structural analysis