Earticle

이 논문은 전형적인 소규모 개방경제라 할 수 있는 한국의 1977～2008년간 분기별 자료를 대상으로 최적화 모형에 기초해 자본이동성의 정도를 평가한다. 자본이동성을 검정하기 위한 추정식은 Shibata and Shintani(1998)와 이를 확장한 Cooray(2005)의 다기간 최적화 모형에서 유도되는 1계 조건을 활용하였다. 특히 완전 자본이동성이 성립하는 경우 순산출은 소비에 대한 설명력을 갖지 못한다는 조건을 활용하였으며 세계이자율의 가변성이 자본이동성에 영향을 미칠 수 있다는 소규모 개방경제의 특징을 감안하였다. 그랜져 인과관계와 1계조건 추정결과 자본이동성을 유의적으로 부정할 수 없음을 확인하였다. 아울러 자본이동성의 구조적 변화 시점은 1997년 1분기로 추정되었지만, 이러한 구조적 전환의 발생에 대한 통계적 유의성은 매우 작았다.

This paper examines the degree of international capital mobility for Korea. By applying the intertemporal optimizing model by Shibata and Shintani(1998) and Cooray (2005), we develop a theory-based estimation method under the assumption of a variable real interest rate to concentrate on the case of a small open economy. The empirical results based on Granger causality test and OLS estimation show that Korea is a relatively free capital mobile economy. Furthermore there did not appear any statistically significant structural break in capital mobility.

Maintaining stable operation of battery swapping stations under time-varying demand is an important issue in Advanced Air Mobility (AAM) operations. This study proposes a predictive control decision model that uses short-term demand information to proactively adjust swapping channels, charging resources, and available battery levels. Three operational strategies were compared: Fixed rule (S1), State response (S2), and Predictive control (S3). The system was modeled as a multi-resource service system with time-dependent aircraft arrivals, and each strategy was evaluated through 100 simulation replications under identical demand and facility conditions. The results showed that S3 reduced the average waiting time to 1.04 min, the waiting probability to 27.31%, and the battery shortage rate to 12.38%, corresponding to reductions of 98.32%, 64.39%, and 73.37%, respectively, compared with S1. In addition, S3 maintained fewer average active swapping channels and chargers than S2 while performing more frequent resource adjustments. These results demonstrate that short-term demand information can support proactive resource allocation and improve service performance and battery supply stability without simply increasing resource deployment.

Urban Air Mobility is expected to resolve some problems in urban transportation such as traffic congestion and air pollution. Various studies for a large-scale commercialization of UAM are being actively conducted. To that end, the UAM Traffic Management system aims at securing a safety and an efficiency of UAM operations. In this study, a risk assessment model is proposed to evaluate the risk of collision between a vehicle and surrounding obstacles. The proposed model is conceived from the past studies for determining a proper separation distance between parallel runways for their independent operations. The model calculates the risk that the surveillance system fails to meet a target level of safety for a given buffer zone size between a designed route and surrounding obstacles. The model is applied to one of the routes proposed in K-UAM roadmap to evaluate its performances.

본 연구의 목적은 최근 새롭게 등장하고 있는 신규 운송서비스에 대해 살펴보고, 이러한 신규 운송서비스에 대한 사회적 수용과 관련된 모델 을 제시하는데 있다. 본 연구에서 제시하고 있는 사회적 수용모델은 기술적 요인(technological), 경제적 요인(economic), 법·제도적 요인(law and political)의 세 가지를 고려하고 있다. 기술적 요인은 편리성과 혁신성의 두 가지로 구성하였으며, 편리성은 접근성과 이용의 편리성으로, 혁신성은 기술진보와 신뢰성으로 구성하였다. 경제적 요인은 시장성과 실용성의 두 가지로 구성하였으며, 시장성은 시장규모와 수익성으로, 실 용성은 편익증가와 비용절감으로 구성하였다. 법·제도적 요인은 법제도와 정책의 두 가지로 구성하였으며, 법제도는 정의성과 공평성으로, 정책 은 안전과 사회문제해결로 구성하였다. 전문가 평가에 의한 중요도 분석결과, 경제적 요인이 0.525로 가장 높은 중요도를 보이고 있으며, 그 다음으로 기술적 요인이 0.325, 마지막으 로 법·제도적 요인의 중요도가 0.149로 조사되었다. 우리나라뿐만 아니라 대부분의 국가에서는 신규 운송서비스의 등장에 따른 집단간 갈등의 문제를 해결하기 위해서 법·제도적 측면의 방법 모색에 집중하고 있는 데, 이에 대한 중요도는 가장 낮은 것으로 나타나고 있다. 따라서 법·제도 적 요인뿐만 아니라 보다 중요도가 더 높은 기술적 요인과 경제적 요인을 추가적으로 고려한 종합적 접근의 해결방안을 모색해야 사회구성원 전 체의 관점에서 합리적인 해결책이 제시될 수 있을 것으로 보인다. 본 연구는 신규 운송서비스에 대한 개인적 차원의 수용을 넘어서 사회적 관점의 수용이 필요한 경우에 활용될 수 있는 사회적 수용 모델을 제 시하였다는 점에서 의의가 있다 할 수 있겠다. 향후 자율주행차, UAM등을 이용한 신규 운송서비스가 출시될 예정인데, 이 경우 사회적 수용 여 부에 대한 의사결정 프레임웍으로 활용 될 수 있을 것으로 기대된다.

The object of this study is to suggest a model of social acceptance for new mobility services. The social acceptance model proposed in this study considers three factors: technological, economic, and law and political. The technological factors consisted of the convenience and the innovation, and the convenience consisted of the accessibility and the ease of use, and the innovation consisted of technological innovativeness and reliability. The economic factors consisted of the marketability and the practicality, and the marketability consisted of the market size and the profitability, and practicality consisted of the benefit increase and the cost reduce. The law and political factors consisted of the legal system and the policy, and the legal system consisted of the justice and the fairness, and the policy consisted of the safety and the social problemsolving. As a result of the importance analysis by AHP(analytic hierarchy process), the economic factor showed the highest importance at 0.525, followed by the technological factor at 0.325, and finally the law and political factor at 0.149. Most countries, as well as Korea, are concentrating on the law and political approach to solve the problem of group conflicts caused by the emergence of newmobility services. The importance of the law and political, however, is shown to be the lowest. Therefore, it is needed that a rational solution can be reflected from the perspective of the entire society members with a comprehensive approach that considers technological and economic factors as well as the law and political factors. This study is meaningful in that it suggests a social acceptance model that can be used when social acceptance perspective is needed beyond the individual acceptance in new mobility services. In the future, new mobility services using self-driving cars and UAMs are expected to be released. In this case, it is expected to be used as a decision-making framework for social acceptance.

Advanced Air Mobility (AAM) systems require efficient ground infrastructures to support high-frequency operations, where battery swapping stations play a critical role. In such environments, energy supply stability significantly affects system performance, particularly under time-varying demand. This study analyzes the impact of different energy supply configurations on battery swapping station performance using a simulation-based approach. Three configurations are considered: external power grid, distributed energy resources (DER), and integrated DER with energy storage systems (ESS). Key performance metrics include average waiting time, system staying time, task completion rate, and battery availability. The results show that grid-based systems experience increased delays under peak demand, while DER-only configurations improve some performance indicators, but their effectiveness remains limited under highly time varying demand due to supply variability. In contrast, the integration of DER and ESS achieves the most stable performance by mitigating energy fluctuations. These findings indicate that the temporal adaptability of energy supply is a critical factor in determining operational performance, highlighting the importance of integrating energy storage systems in AAM infrastructure design.

While active research on Urban Air Mobility(UAM) is being conducted, interest in urban planning is insufficient. UAM's operating model and ground infrastructure are closely related to urban planning. Therefore, the purpose of this study is to classify the UAM operation model and ground infrastructure. For this, literature analysis was conducted. The results of the analysis are as follows. First, the operation model was largely divided into passenger transport, cargo transport and special purposes. The passenger operating model was categorized into Air Metro, Air Taxi, Airport Shuttle, MaaS, and PAV. The cargo operation model was categorized into Last-mile delivery and Air Cargo. The special purpose operation model was categorized into Air Ambulance and Medical Transfer. Second, ground infrastructure was largely divided into small size, medium size and large size. Small infrastructure includes a rooftop station type and a ground station type. There are two types of large infrastructure: a terminal type located in the city center and a garage type located in a suburban area.

현재 수립된 대부분의 교통약자관련 이동편의증진계획에서는 투자우선순위를 결정함에 있어 교통약자 이동편의시설의 설치율과 만족도간의 중요도(요인 적재량)에 대한 분석 없이 설치율 또는 만족도가 낮은 항목을 우선적으로 고려하여 투자우선순위를 결정하고 있다. 따라서 본 연구에서는 구조방정식(SEM: Structural Equation Model)을 이용하여 외생잠재변수(Exogenous Latent Variables)와 내생잠재변수(Endogenous Latent Variables)간의 인과관계를 통계적으로 검증하고 설치율과 만족도를 동시에 고려한 교통약자 이동편의시설의 투자우선순위 결정모형을 제시하였다. 분석결과 이동편의 시설가운데 이용자 만족도에 가장 큰 영향을 주는 시설로는 버스정류장, 횡단보도, 보도 순으로 분석되었다. 버스정류장시설 중 정류장연석의 높이, 보도시설 중 보도의 평탄성 그리고 횡단보도시설 중 보행신호등 설치에 대한 중요도가 높게 분석되었다.

In most of mobility enhancing plans for the transportation disabled, decisions for the investment priorities are firstly made by the facilities that have lower installation rate or lower satisfaction rate; the decisions are made without analyzing the importance factor (path loading factor) between the facility installation rate and the satisfaction rate together. In this study, a novel method of finding causality between the exogenous latent variables and the endogenous latent variables is provided by using the Structural Equation Model (SEM). The results show that the most influential facilities for the transportation disabled are bus stops, crosswalks and sidewalks in order. Also, a curb height around bus stops, a smoothness of sidewalks and installation of crosswalks traffic light are identified as an important facilities for the Transportation disabled.

목적 : 본 연구는 한국 고령자의 지역사회 이동 독립성 유지 및 상실에 영향을 미치는 다차원적 요인을 종단적으로 분석하여, 고령자의 지역사회 이동 독립성을 유지한 건강한 노후 생활을 지원하기 위한 예방적 작업치료 중재 방안을 제언하였다. 연구방법 : 고령화연구패널조사 1∼9차 원자료를 활용하여 65세 이상 고령자 471명을 대상으로 분석을 수행하였다. 지역사회 이동성 모델을 기반으로 참여적, 신체적, 심리사회적, 환경적, 경제적 요인을 독립변수로 설정하였으며, Cox 비례위험모형을 적용하여 생존 분석을 실시하였다. 결과 : 추적 관찰 기간 동안 전체 대상자의 29.1% (137명)에서 지역사회 이동 독립성 제한이 발생하였다. 주요 영향요인으로 수단적 일상생활활동 점수 상승, 악력의 증가, 친한 사람과의 잦은 만남이 이동 제한 위험을 유의하게 낮추는 보호 요인으로 확인되었다. 반면, 관절질환, 뇌혈관질환, 낙상 경험은 위험을 증가시키는 요인으로 나타났다. 환경적, 경제적 요인은 통계적으로 유의하지 않았다. 결론 : 고령자의 지역사회 이동 독립성은 신체적 기능과 더불어 수단적 일상생활활동 수행 능력, 사회적 관계망 형성과 깊은 관련이 있다. 기능 저하를 사전에 방지하기 위해 악력 유지, 낙상 예방, 지역사회 내 작업 참여를 촉진하는 포괄적인 작업치료 중재 전략이 필요하다.

Objective : This study longitudinally analyzed the multidimensional factors affecting the maintenance and loss of community mobility independence in Korean older adults. It aims to suggest preventive occupational therapy interventions that support a healthy later life by maintaining this independence. Methods : An analysis was conducted on 471 older adults aged 65 and older using raw data from waves 1 to 9 of the Korean Longitudinal Study of Ageing (KLOSA). Based on a community mobility model, participatory, physical, psychosocial, environmental, and economic factors were set as independent variables. Survival analysis was performed using the Cox proportional hazards model. Results : During the follow-up period, 29.1% (137 participants) of the subjects experienced limitations in community mobility independence. Higher scores in instrumental activities of daily living (IADL), increased grip strength, and frequent contact with friends were identified as protective factors that significantly reduced the risk of mobility restriction. Conversely, joint disease, cerebrovascular disease, and a history of falls were found to increase the risk. Environmental and economic factors were not statistically significant. Conclusion : Community mobility independence in older adults is closely associated not only with physical function but also with IADL performance and the formation of social networks. To proactively prevent functional decline, comprehensive occupational therapy intervention strategies are needed to promote maintaining grip strength, preventing falls, and encouraging occupational participation within the community.

정부는 교통운영체계 선진화를 위하여 지속적인 교통시설 및 운영방식 개량, 그리고 교육 및 단속 등을 실시하여 왔다. 그러한 많은 노력에도 불구하고 우리나라 교통신호와 도로운영체계가 불합리하다는 지적이 지속적으로 제기되어 왔다. 이러한 원인 중에 하나는 정부가 제시한 대안들에 대하여 체계적이고 과학적인 사전 평가가 부족하였기 때문이다. 또한, 다양한 교통운영체계 대안에 대한 이동성 및 안전성을 종합적으로 분석할 수 있는 도구가 부족하였다. 따라서, 본 연구에서는 이러한 종합적인 평가 도구로써 미시교통분석모형의 체계적인 활용을 제안하며, 분석사례로 공용 좌회전 차로에 중첩현시가 적용 중인 대상교차로는 다양한 시나리오 하에서 안전성과 이동성을 평가하였다. 그 결과 공용 좌회전 차로에서 중첩현시의 적용은 이동성은 큰 차이가 없으나 안전성 측면에서 불리한 것으로 나타났다. 또한 전체 및 직진교통량 증가를 가정한 민감도 분석에서는 중첩현시가 가장 좋은 이동성을 보이나 안전성 측면에서 크게 나빠지는 것을 계량적으로 증명하였다.

Government agencies including the national police agency have executed diverse efforts including continuous improvements of traffic facilities and operation methods, education, enforcements in order to improve traffic operation systems; nevertheless there have been continuous criticisms on irrationality in traffic signal and road facility operation. One of the reasons may be the lack of systematic preliminary evaluations on various alternatives. However, there was no appropriate tool to evaluate the mobility and safety of thus alternatives in a systematic way. Therefore, this study proposes the systematic use of microscopic traffic simulation models as a comprehensive evaluation tool. In addition, this study verified the potential of using a microscopic traffic simulation model using the case of operating an overlap phase on a shared-left-turn lane through a systematic way where the evaluation was conducted through data collection, building networks, calibrating microscopic simulation models, producing performance measures, evaluating mobility and safety, and so on. As a result, the operation of overlap phase on a shared-left-turn lane showed no big difference from other operation scenarios such as leading left-turn on exclusive left turn lane in terms of mobility. However the operation of overlap phase on a shared-left-turn lane decreased safety by increasing potential conflicts.

본 연구는 SOR(Stimulus-Organism-Response) 모델을 기반으로 퍼스널 모빌리티의 성능적 측면과 외부 환경적 요인을 고려해 이용자들과 비이용자들의 사용 의도를 설명할 수 있는 연구 모형을 제안하였다. 국내 사용자들과 비사용자들을 대상으로 설문조사를 진행하였고 부분최소자승법(Partial Least Square, PLS)과 인공신경망 분석(Artificial Neural Network, ANN)을 통해 연구모형 및 가설들을 검증하였다. 분석결과, 사용자들은 지각된 만족도와 지각된 신뢰도가 사용 의도에 긍정적인 영향을 미치고, 지각된 위험성과 환경적 가치가 지각된 만족도와 지각된 신뢰도와 유의한 관계가 있음이 확인되었다. 반면, 비사용자들은 지각된 만족도와 사용의도 간에 양의 상관관계가 있음이 밝혀졌고, 사용자들과 마찬가지로 지각된 위험성과 환경적 가치가 지각된 만족도와 지각된 신뢰도의 유의한 선행변수임이 검증되었다. 나머지 변수들 중에서는 사용자들의 지각된 이동성과 비사용자들의 지각된 이용 용이성이 각각 지각된 만족도의 중요한 영향요인으로 파악되었다.

This study proposed a research model that can explain the usage intentions of users and non-users by considering the performance aspects of personal mobility and external environmental factors based on the SOR (Stimulus-Organism-Response) model, A survey was conducted targeting domestic users and non-users, and research models and hypotheses were verified through Partial Least Square (PLS) and Artificial Neural Network (ANN). As a result of the analysis, it was confirmed that the users' perceived satisfaction and perceived trust had a positive effect on their intention to use, and that perceived risk and environmental value had a significant relationship with perceived satisfaction and perceived trust. For non-users, it was found that there was a positive correlation between perceived satisfaction and intention to use, and it was verified that perceived risk and environmental value, like users, were significant antecedents of perceived satisfaction and perceived trust. Among the remaining variables, the perceived mobility of users and the perceived ease of use of non-users were respectively presented as important influencing factors on perceived satisfaction.

최근 항공산업 분야의 최대 이슈로 부각되고 있는 UAM(Urban Air Mobility)은 국내 뿐아니라 국제적으로 많은 관심이 집중되고 있다. 현재 우리나라는 미래 K-UAM 운용개념서 제정 등 정부 및 산학연을 중심으로 활발한 연구가 진행되고 있으나 아직까지 비행안전의 핵심 요소인 K-UAM 운용 환경에 대한 위험도 평가 방안은 마련되어 있지 않다. 따라서 본 논문에서는 유럽 JARUS(Joint Authorities for Rulemaking on Unmanned Systems)에서 제정한 SORA(Specific Operation Risk Assessment) 모델을 적용하여 정부가 추진하고 있는 화물 운송 목적의 K-UAM 운용 환경 및 특정 회랑을 대상으로 위험도를 평가하고 그에 따른 결과 분석을 통해 위험도 완화를 위한 정책 및 기술적 방안을 제시하고자 한다.

UAM is emerging as the biggest issue in the aviation industry and which is attracting a lot of attention not only domestically but also internationally. In Korea, active research is being conducted centered on the government and industry-university research institutes, such as the establishment of a future K-UAM concept of operation. Therefore, in this study applies the SORA (Specific Operation Risk Assessment) model established by the European JARUS (Joint Authorities for Rulemaking on Unmanned Systems) to apply the K-UAM operation environment and specific corridor for the purpose of cargo transportation that will be operated in the future that the government is promoting. We intend to suggest policy and technical measures for risk mitigation in the initial operating environment by evaluating the level of risk and analyzing the results.

Recently aircraft ad hoc networks have received attention from many researchers since ad hoc network technology is expected to play a great role in communications between aircrafts. Due to large number of aircrafts as well as high bandwidth to meet emerging demands such as multimedia stream, ad hoc networks can be practical approach in this situation. However, since aircraft ad hoc networks possess significantly different properties to typical MANET or VANET, many research challenges remains unsolved yet. Among them, simulation study is one of key research area by providing simulation scenarios through simulator. Despite of importance, since current popular simulators do not provide the simulation environments for aircraft ad hoc networks, it is strongly required to extend the current simulators by adding several elements such as mobility model, type of node and so on. Based on above research needs, in this paper, we propose how to implement the realistic mobility scenarios for aircraft ad hoc network. To design the relevant model, we implement new software which connects it to commercial flight simulator to generate mobility trace file. This file is converted to corresponding mobility file for each simulator. The software developed by .NET will be presented to validate its operation by diverse experiments.

Followed by our previous works, a study for performance evaluation of existing typical routing protocols for aircraft ad hoc networks is presented in this paper. The main objective of this evaluation is to figure out the impact of high speed movement and spare deployment over well-known routing protocols with new mobility pattern for aircraft ad hoc networks. The chosen protocols are three major protocols according to general categorization, this is, AODV, DSDV, and GPSR. By analyzing the result of performance evaluation, we demonstrate the suitability of those in aircraft ad hoc networks in the terms of packet delivery ratio, end-to-end delay and control overhead and discuss further works in this research area. Finally, rough conclusion is made that it is necessary to develop new routing protocol based on DTN for aircraft ad hoc networks.