• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제6권9호
• /
• pp.2170-2190
• /
• 2012

There are nowadays strong demands for intelligent surveillance systems, which can infer or understand more complex behavior. The application of crowd density estimation methods could lead to a better understanding of crowd behavior, improved design of the built environment, and increased pedestrian safety. In this paper, we propose a new crowd density estimation method, which aims at estimating not only a moving crowd, but also a stationary crowd, using images captured from surveillance cameras situated in various public locations. The crowd density of the moving people is measured, based on the moving area during a specified time period. The moving area is defined as the area where the magnitude of the accumulated optical flow exceeds a predefined threshold. In contrast, the stationary crowd density is estimated from the coarseness of textures, under the assumption that each person can be regarded as a textural unit. A multilayer neural network is designed, to classify crowd density levels into 5 classes. Finally, the proposed method is experimented with PETS 2009 and the platform of Gangnam subway station image sequences.

• 한국재난정보학회 논문집
• /
• 제7권1호
• /
• pp.12-20
• /
• 2011

본 연구는 군중집회 및 군중눌림 현상의 문헌조사 및 분석에 근거하여 군중집회 및 군중집회에서의 인명피해의 특성을 알아보고자 수행되었다. 대규모 군중집회 시 인명 피해의 특성은 참가자 수와 군중 밀도가 군중집회 종류와 특성에 따라 다른 영향을 미치고 있었다. 군중 집회에 영향을 주는 변수와 그 원인들은 상황에 따라 다양한 정 혹은 부의 영향을 미치고 있었으며 그 변수들은 날씨, 참가자 수, 행사 기간, 실외와 실내, 착석과 이동, 행사 유형, 군중 감정상태, 술 혹은 약물, 군중 밀도, 관련 시설, 참가자 연령 등이었다. 이 중 군중 눌림현상은 실험적으로도 연구가 가능하였고, 사고가 유발되는 물리적 기전으로 보아 군중 압력과 군중 밀도 및 압력의 지속 시간에 영향을 받았으나 사망에 이르는 구체적인 압력 수치를 도출하려면 인간 신체와 관련된 여러 외부적 영향으로 인하여 추가적 연구가 더 필요하다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제15권8호
• /
• pp.2974-2992
• /
• 2021

Crowd-based outsourcing is an emerging trend in testing, which integrates advantages of crowd-based outsourcing in software testing. Open call format is used to accomplish various network tasks involving different types of testing levels and techniques at various places by software testers. Crowd-sourced software testing can lead to an improper testing process as if it does not allocate the right task to the right crowd with required skills and not choose the right crowd; it can lead to huge results, which become time-consuming and challenging crowd-source manager for the identification of improper one. The primary purpose of this research is to make crowd-based outsourced software testing more effective and reliable by relating association between the software tester, personality characteristic, and different levels of software testing, i.e., unit, integration, and system, in order to find appropriate personality characteristic for required testing level. This research has shown an observed experiment to determine which software testing level suits which personality characteristic tester in a crowd-based software testing environment. A total of 1000 software testers from different software houses and firms in Pakistan were registered to perform tasks at different software testing levels. The Myers-Briggs Type Indicator (MBTI) test is used to identify each tester's personality characteristic involved in this research study.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제12권9호
• /
• pp.4355-4374
• /
• 2018

Crowd escape event detection has become one of the hottest problems in intelligent surveillance filed. When the 'escape event' occurs, pedestrians will escape in a disordered way with different velocities and directions. Based on these characteristics, this paper proposes a Direction-Collectiveness Model to detect escape event in crowd scenes. First, we extract a set of trajectories from video sequences by using generalized Kanade-Lucas-Tomasi key point tracker (gKLT). Second, a Direction-Collectiveness Model is built based on the randomness of velocity and orientation calculated from the trajectories to express the movement of the crowd. This model can describe the movement of the crowd adequately. To obtain a generalized crowd escape event detector, we adopt an adaptive threshold according to the Direction-Collectiveness index. Experiments conducted on two widely used datasets demonstrate that the proposed model can detect the escape events more effectively from dense crowd.

• 벤처창업연구
• /
• 제9권1호
• /
• pp.97-105
• /
• 2014

본 연구는 크라우드 펀딩(Crowd Funding)과 관련된 이론 및 관련 연구성과를 검토하고 크라우드 펀딩의 벤처창업에의 활용 가능성을 분석하는 데에 그 목적을 두고 있다. 이를 위해서 최근 정보기술 분야의 우수 논문들에서 논의되고 있는 이론과 프레임워크를 분석한 후, 크라우드 펀딩의 이론적 틀을 제시하며, 벤처창업의 관점에서 크라우드 펀딩 플랫폼의 활용 가능성을 모색하였다. 본 연구에서는 크라우드 펀딩의 프로젝트 라이프 사이클과 이해당사자 분석에 기초한 이론적 프레임워크를 제시하고 주요 부문 별로 크라우드 펀딩의 장단점 분석을 수행하고 크라우드 펀딩 플랫폼의 벤처창업 가능성을 기존 우수 연구를 검토함으로써 분석하였다. 분석 결과, 크라우드 펀딩의 다수를 차지하고 있는 정보재의 특성 상 고정 비용이 높고 가변 비용이 상당히 작기 때문에 고정 비용의 사업 위험성을 대중의 지혜를 통해 심사하고 초기 수요를 확보함으로서 초기 벤처의 위험을 관리할 수 있다는 측면에서 초기 벤처의 자금 플랫폼으로써 긍정적인 기대효과가 예상된다. 하지만, 이전 연구결과를 검토해본 바, 정보의 비대칭성으로 말미암아 대중의 지혜가 작동하지않고 집단사고로 흘러 크라우드 펀딩이 심사 능력이 발휘되지 못할 경우에는 초기 벤처에 또 다른 위협이 될 수 있다. 본 연구결과는 크라우드 펀딩의 이론적 이해와 더불어 벤처 창업 활용 가능성에 대한 분석으로 창조경제를 지향하는 정부의 정책적 지원 방안의 기초자료가 될 수 있다는 추가적인 시사점을 찾을 수 있으며 향후 후속연구를 통해 프레임워크 활용가능성을 실증 연구할 예정이다.

• 한국IT서비스학회지
• /
• 제13권4호
• /
• pp.123-137
• /
• 2014

Since the global financial crisis, funding for startups or ventures has been diminished seriously. In this situation, crowd-funding has attracted worldwide attention as a viable means to financing startups/ventures. After reviewing existing laws in other countries, this study investigated the current status of crowd-funding legalization in Korea and surveyed requirements from three groups of participants to crowd-funding. Investors already recognized the high risk of crowd-funding into startups and asked for the protection of their investment. But, their priorities were on the enlargement of tax benefits and the establishment of a trading market for selling their equity. In addition, investors wanted to shorten the compulsory holding period. Issuers as fund raisers hoped fast legalization, convenient process of crowd-funding, and expansion of government support. Crowd-funding platform operators requested policies for establishing paths to become new growth companies from startups, tax benefits, and the setup of separate fund for startups. Currently, the National Assembly in Korea is holding the discussion on the submitted law. For desirable outcomes to all participants, it would be better to proceed in the following sequence. First, legalize the crowd-funding with clauses protecting investors; Second, encourage investment through tax benefits; Third, develop communities among participants for reducing information asymmetry; And fourth, establish diverse trading markets for selling equities of startups.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제12권8호
• /
• pp.3769-3789
• /
• 2018

Social pedestrian groups are the basic elements that constitute a crowd; therefore, detection of such groups is scientifically important for modeling social behavior, as well as practically useful for crowd video understanding. A social group refers to a cluster of members who tend to keep similar motion state for a sustained period of time. One of the main challenges of social group detection arises from the complex dynamic variations of crowd patterns. Therefore, most works model dynamic groups to analysis the crowd behavior, ignoring the existence of stationary groups in crowd scene. However, in this paper, we propose a novel unified framework for detecting social pedestrian groups in crowd videos, including dynamic and stationary pedestrian groups, based on spatiotemporal-oriented energy measurements. Dynamic pedestrian groups are hierarchically clustered based on energy flow similarities and trajectory motion correlations between the atomic groups extracted from principal spatiotemporal-oriented energies. Furthermore, the probability distribution of static spatiotemporal-oriented energies is modeled to detect stationary pedestrian groups. Extensive experiments on challenging datasets demonstrate that our method can achieve superior results for social pedestrian group detection and crowd video classification.

• 한국강구조학회 논문집
• /
• 제24권1호
• /
• pp.1-11
• /
• 2012

군중하중을 받는 현행 바닥진동 설계절차의 한계를 극복하기 위해서는 개인별 운동의 시간차와 운동성분에 내재된 위상의 불확실성이 고려되어야 한다. 개인의 운동에 관한 연구는 통계적 자료를 토대로 많은 연구가 진행되고 있는 반면, 군중 행동패턴에 관한 연구는 그 복잡성으로 인해 연구가 미흡한 실정이다. 본 연구에서는 다양하고 복잡한 군중의 행동패턴을 개인 간의 위상을 반영한 하중모형을 제안한다. 모의실험을 통해 개인의 시간지연 값들을 난수로 발생시킨 후, 기준시간에 대한 시간 지연효과를 합산하였다. 본 연구에서 제안하는 위상의 합산으로 이루어진 계수는, 완전히 동기화된 군중의 경우에 대한 동기화 정도의 비를 나타낼 수 있다. 정의된 계수를 바탕으로 실제 일어날 수 있는 군중의 행동패턴을 분석하여 각각의 경우에 대한 계수 값을 제안하였다. 본 연구의 결과를 토대로 기존의 설계방식이 다룰 수 없었던 군중의 운동시 바닥구조의 응답을 합리적으로 반영할 수 있다.

• 한국멀티미디어학회논문지
• /
• 제17권9호
• /
• pp.1104-1114
• /
• 2014

In large-scale crowd simulations, it is very important for the decision-making system of manipulating interactive behaviors to minimize the computational cost for controlling realistic behaviors such as collision avoidance. In this paper, we propose a large-scale realtime crowd simulation method using the affordance and navigation potential fields such as attractive and repulsive forces of electromagnetic fields. In particular, the model that we propose locally handles the realistic interactions between agents, and thus radically reduces the cost of expensive computation on interactions which has been the most problematic in crowd simulation. Our method is widely applicable to the expression and analysis of various crowd behaviors that are needed in behavior control in computer games, crowd scenes in movies, emergent behaviors of evacuation, etc.

• Industrial Engineering and Management Systems
• /
• 제14권4호
• /
• pp.325-334
• /
• 2015

Nowadays, crowdsourcing has become a popular concept and is widely used in many social, economical and technological areas. For consumer product design, crowdsourcing is implemented extensively with many cases. Although there has been a lot of research on the application of crowdsourcing for product design, the big picture of how factors influence the participartion of individuals from the crowd in a crowdsourcing project for product design has not yet been understood. This paper aims to investigate the relationships of crowd participation and influencing factors including: process, product, and reward. To do this, we conducted a survey on a crowd of engineering individuals and analyzed the collected data with data mining techniques. Main findings include the relationships of crowd participation versus process, product, and reward factors as well as regression models to predict crowd participation.