• Title/Summary/Keyword: Reality Check Test

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Reality Check Test on the Momentum and Contrarian Strategy (모멘텀전략과 반대전략에 대한 사실성 체크검정)

  • Yoon, Jong-In;Kim, Sung-Soo
    • The Korean Journal of Financial Management
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    • v.26 no.1
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    • pp.189-220
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    • 2009
  • This study tests the significance of momentum and contrarian strategy which challenge the weak efficient market hypothesis (EMH). If momentum and contrarian strategy can make extra return above the market, this can be a significant critics to the weak EMH. By using Monte Carlo simulation we have found that many existing returature, which test the significance of momentum and contrarian strategy, have a significance distortion problem. We test the significance of momentum and contrarian strategy by using reality check test of White(2000) which solve the problem of data snooping bias. The results are following. When we use the KOSPI index as the benchmark portfolio, we can get the best strategy of momentum strategy in the case of mean return. But in the case of Sharp ratio which is the performance measure adjusting risk, we find that the best strategy in the momentum and contrarian strategy can not dominate the performance of benchmark portfolio. Therefore we argue that weak EMH can not be rejected because of superior performance of momentum and contrarian strategy when we consider risk.

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The Effects of Virtual Reality-Based Occupational Therapy Program on the Physical Function and Learning Capacity of School-Age Intellectual Disability Children (가상현실 기반 작업치료프로그램이 학령기 지적장애 아동의 신체기능 및 학습능력에 미치는 영향)

  • Kim, Ko-Un;Oh, Hye-Won
    • Journal of The Korean Society of Integrative Medicine
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    • v.9 no.1
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    • pp.13-22
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    • 2021
  • Purpose : The purpose of this study was to investigate the effects of a virtual reality-based occupational therapy program on the physical function and learning ability of intellectually disabled school-aged children. Methods : In this study, 20 intellectually disabled children of school age were randomly and evenly divided into experimental and control groups with children in the experimental group receiving a virtual reality-based occupational therapy intervention. The study adopted a pretest-posttest design. The intervention was conducted for a total of 12 sessions for six weeks, twice a week, and 50 minutes per session. As measurement tools, BOT-2 and grooved pegboard tests were used to compare physical function before and after the intervention program, and K-ABC was used to check changes in learning ability. Results : The occupational therapy program produced a significant improvement in both physical function and learning ability of the experimental group. A significant difference was observed between the experimental and control groups. Conclusion : This study confirmed the value and usefulness of virtual reality-based occupational therapy as a tool for enhancing the physical function and learning ability of intellectually disabled school-aged children. Based on the results, a variety of future studies are encouraged that would further test the effects of the occupational therapy program used here.

Space Management on Campus of a Mobile BIM-based Augmented Reality System

  • Ji, Seung-Yeul;Kim, Mi-Kyoung;Jun, Han-Jong
    • Architectural research
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    • v.19 no.1
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    • pp.1-6
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    • 2017
  • Over the past decade, building information modeling (BIM) has gained a foothold in the construction sector. However, as digital data generated in the virtual space of a computer environment, BIM-based data have an inherent limitation in their application efficacy under field conditions. To overcome this, the present study employs augmented reality (AR) to reduce the discrepancy between the digital data generated in virtual spaces and real-world conditions. We assessed the potential applicability of an AR-based interface by analyzing existing examples of Apple, Google, and Facebook, which reflect the recent developments of technologies focusing on user experience. We then proceeded with an AR study, restricting the scope of application to a mobile environment in which an efficient information transmission between a digital model and real life can take place. Object-oriented software engineering was employed to ensure an efficient implementation of a BIM-based AR system for campus space management (CSM) in a mobile environment. Finally, we conducted a module test to check the reliability of the CSM method by using an AR-based mobile system with a prototype of the model used in university campuses, and extracted and itemized the supplementary requirements for CSM by using BIM tools for running AR applications.

Application of Human Machine Interface and Augmented Reality Technology to Flight Operation (인간-기계 인터페이스 및 증강현실 기술의 항공운항 분야 적용)

  • Park, Hyeong Uk;Chung, Joon;Chang, Jo Won;Joo, Seonghyeon;Hwang, Young Ha
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.27 no.2
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    • pp.54-69
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    • 2019
  • The primary objective of this paper is to introduce the application of Human-Machine Interface (HMI) and Augmented Reality (AR) technologies in flight operations. These include: self-check-in, baggage handling, airport security and surveillance, airport operations monitoring, In-Flight Entertainment and Connectivity (IFEC), cockpit design, and cabin crew support. This paper investigates the application status and development trends of HMI and AR technologies for airports and aircraft. These technologies can provide more efficient in-flight passenger service and experience by using AR devices. This paper also discusses the developments such as; the Integrated Control Application (ICA) for the IFEC interface, AR flight simulation training program using the fixed-based simulator, and the AR aircraft cabin interior concept test program. These applications present how HMI and AR techniques can be utilized in actual flight operations. The developed programs in this paper can be applied to their purpose within aircraft interiors and services to enhance efficiency, comfort, and experience.

Efficient distribution support of Shipping Request Data based on Digitalized Character Recognition (디지털 문자 판독기술을 적용한 선적요청서 데이터의 효율적인 유통지원)

  • Park, Joon-Hyuk;Goh, Hyun-Woo
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.31 no.2
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    • pp.112-121
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    • 2008
  • Nowaday the supply chain competitiveness is emphasized more and more than a company's own competitiveness. One of the most important processes in import and export is a publication over the Bill of Loading. In the publication of those bills S/R(shipping request) and check B/L for reviewing are circulated among consignors, forwarders, shipping companies and airlines by fax and e-mail. Or there should be expensive a One to One system, like an EDI. Each party has to re-input S/R data to their own systems and check it several times. The S/R data are converted digital to analog type and analog to digital repeatedly to check in the process. As the process goes by there can be not only input data errors but also waste of time and cost. ECR(electronic character recognition) is a technology can solve the Problem. Considering the data structure of documents in many systems used ECR samples SIR data from documents written in the digital type. But it is not enough with it only. To make N to N composition in reality more efficient we make a documents hub on the web reengineering the existing process to One to One relation. The ECR documents hub system has given us beneficial effects over a year throughout a field test.

The Effects of Virtual Reality Advertisement on Consumer's Intention to Purchase: Focused on Rational and Emotional Responses (가상현실(Virtual Reality) 광고가 소비자 구매의도에 미치는 영향: 이성적인 반응과 감성적인 반응의 통합)

  • Cha, Jae-Yol;Im, Kun-Shin
    • Asia pacific journal of information systems
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    • v.19 no.4
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    • pp.101-124
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    • 2009
  • According to Wikipedia, virtual reality (VR) is defined as a technology that allows a user to interact with a computer-simulated environment. Due to a rapid growth in information technology (IT), the cost of virtual reality has been decreasing while the utility of virtual reality advertisements has dramatically increased. Nevertheless, only a few studies have investigated the effects of virtual reality advertisement on consumer behaviors. Therefore, the objective of this study is to empirically examine the effects of virtual reality advertisement. Compared to traditional online advertisements, virtual reality advertisement enables consumers to experience products realistically over the Internet by providing high media richness, interactivity, and telepresence (Suh and Lee, 2005). Advertisements with high media richness facilitate consumers' understanding of advertised products by providing them with a large amount and a high variety of information on the products. Interactivity also provides consumers with a high level of control over the computer-simulated environment in terms of their abilities to adjust the information according to their individual interests and concerns and to be active rather than passive in their engagement with the information (Pimentel and Teixera, 1994). Through high media richness and interactivity, virtual reality advertisements can generate compelling feelings of "telepresence" (Suh and Lee, 2005). Telepresence is a sense of being there in an environment by means of a communication medium (Steuer, 1992). Virtual reality advertisements enable consumers to create a perceptual illusion of being present and highly engaged in a simulated environment, while they are in reality physically present in another place (Biocca, 1997). Based on the characteristics of virtual reality advertisements, a research model has been proposed to explain consumer responses to the virtual reality advertisements. The proposed model includes two dimensions of consumer responses. One dimension is consumers' rational response, which is based on the Information Processing Theory. Based on the Information Processing Theory, product knowledge and perceived risk are selected as antecedents of intention to purchase. The other dimension is emotional response of consumers, which is based on the Attitude-Structure Theory. Based on the Attitude-Structure Theory, arousal, flow, and positive affect are selected as antecedents of intention to purchase. Because it has been criticized to have investigated only one of the two dimensions of consumer response in prior studies, our research model has been built so as to incorporate both dimensions. Based on the Attitude-Structure Theory, we hypothesized the path of consumers' emotional responses to a virtual reality advertisement: (H1) Arousal by the virtual reality advertisement increases flow; (H2) Flow increases positive affect; and (H3) Positive affect increases intension to purchase. In addition, we hypothesized the path of consumers' rational responses to the virtual reality advertisement based on the Information Processing Theory: (H4) Increased product knowledge through the virtual reality advertisement decreases perceived risk; and (H5) Perceived risk decreases intension to purchase. Based on literature of flow, we additionally hypothesized the relationship between flow and product knowledge: (H6) Flow increases product knowledge. To test the hypotheses, we conducted a free simulation experiment [Fromkin and Streufert, 1976] with 300 people. Subjects were asked to use the virtual reality advertisement of a cellular phone on the Internet and then answer questions about the variables. To check whether subjects fully experienced the virtual reality advertisement, they were asked to answer a quiz about the virtual reality advertisement itself. Responses of 26 subjects were dropped because of their incomplete answers. Responses of 274 subjects were used to test the hypotheses. It was found that all of six hypotheses are accepted. In addition, we found that consumers' emotional response has stronger impact on their intention to purchase than their rational response does. This study sheds much light into practical implications for both IS researchers and managers. First of all, while most of previous research has analyzed only one of the customers' rational and emotional responses, we theoretically incorporated and empirically examined both of the two sides. Second, we empirically showed that mediators such as arousal, flow, positive affect, product knowledge, and perceived risk play an important role between virtual reality advertisement and customer's intention to purchase. In addition, the findings of this study can provide a basis of practical strategies for managers. It was found that consumers' emotional response is stronger than their rational response. This result indicates that advertisements using virtual reality should focus on the emotional side, and that virtual reality can be served as an appropriate advertisement tool for fancy products that require their online advertisements to give an impetus to customers' emotion. Finally, even if this study examined the effects of virtual reality advertisement of cellular phone, its findings could be applied to other products that are suited for virtual experience. However, this research has some limitations. We were unable to control different kinds of consumers and different attributes of products on consumers' intention to purchase. It is, therefore, deemed important for future research to control the consumer and product types for more reliable results. In addition to the consumer and product attributes, other variables could affect consumers' intention to purchase. Thus, the future research needs to find ways t control other variables.

A View-Frustum Culling Technique Using OpenGL for Large Polygon Models (OpenGL을 이용한 대용량 Polygon Model의 View-Frustum Culling 기법)

  • Cho, Doo-Yeoun;Jung, Sung-Jun;Lee, Kyu-Yeul;Kim, Tae-Wan;Choi, Hang-Soon;Seong, Woo-Jae
    • Journal of Korea Game Society
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    • v.1 no.1
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    • pp.55-60
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    • 2001
  • With rapid development of graphic hardware, researches on Virtual Reality and 3D Games have received more attention than before. For more realistic 3D graphic scene, objects were to be presented with lots of polygons and the number of objects shown in a scene was remarkably increased. Therefore, for effective visualization of large polygon models like this, view-frustum culling method, that visualizes only objects shown in the screen, has been widely used. In general, the bounding boxes that include objects are generated firstly, and the boxes are intersected with view-frustum to check whether object is in the visible area or not. Recently, an algorithm that can check in-out test of objects using OpenGL's selection mode, which is originally used to select the objects in the screen, is suggested. This algorithm is fast because it can use hardware acceleration. In this study, by implementing and applying this algorithm to large polygon models, we showed the efficiency of OpenGL assisted View-Frustum Culling algorithm. If this algorithm is applied to 3D games that have to process more complicated characters and landscapes, performance improvement can be expected.

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Application of Object Modeling and AR for Forest Field Investigation (산림 현장조사를 위한 객체 모델링과 AR의 활용)

  • Park, Joon-Kyu;Oh, Myoung-Kwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.411-416
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    • 2020
  • Field investigations of forests are carried out by writing measured data by hand, and it is a hassle to reorganize the results after a field survey. In this study, a method using object modeling and augmented reality (AR) was applied in a test forest to increase the efficiency of a field investigations. Using a 3D laser scanner, data on were acquired 387 trees within an area of 1 ha at the study site. The coordinates, height, and diameter were calculated through object extraction and modeling of a tree. The proposed can reduce the time required to acquire data in the field and can be used as basic data for building related systems. In addition, the modeling results of trees and a survey using GNSS and AR techniques can be used check coordinates, labor, and attribute information, such as the chest height diameter of the trees being surveyed in the field. The shortcomings of the survey method could be improved. In the future, the method could greatly improve the efficiency of tree surveys and monitoring by reducing the manpower and time required for field surveys.

A Study on the Design of Visual-Auditory Haptic Interface - With emphasis on embodying Haptics using Visual and Auditory perception (시/청각적 촉감 인터페이스 디자인에 관한 연구 - 시각과 청각을 이용한 촉감 구현을 중심으로)

  • 백승화;김명석
    • Archives of design research
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    • v.14 no.2
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    • pp.15-25
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    • 2001
  • With the rapid development of current internet, digital age make human beings intangible. Haptic sense was recognized less important than visual sense and auditory sense, but it plays an important role in determining the quality of products. The goals of this study are embodying haptics using Visual and Auditory preception and designing Visual-Auditory Haptic interface, in the case of actual touching is required but impossible. This study was carried out 3 steps. Firstly, developing the concept of Visual-Auditory Haptic Interface(VAHI) was carried out to make it certain the direction of this study. To get common factors of VAHI, this study researched physical-mechanism of visual, auditory, and haptics senses, and psychological-mechanism. Secondly, identifying factors of V/A haptic sense was analysed by web-evaluation test, to be categorized 11 Emotional Haptic Factors(EHF) and some Design Haptic Factors(DHF). The relation of EHF and DHF was analysed and summarized to VAHI design check sheet. Finally, Applying DHF to VAHI by EHF according to VAHI design check sheet was validated by web-evaluation test, to be resulted 13% increase in reliability and the same in usability. Conclusively, the possibility of embodying haptics using Visual and Auditory preception was resulted to be valid. And this concept can be applied to an interface, such a internet shopping mall and virtual reality, which requires actual touching to perceive haptic information, but it is impossible.

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Improvement Mechanism for Automatic Web Vulnerability Diagnosis (웹취약점 자동진단 개선방안)

  • Kim, Tae-Seop;Jo, In-June
    • The Journal of the Korea Contents Association
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    • v.22 no.2
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    • pp.125-134
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    • 2022
  • Due to the development of smartphone technology, as of 2020, 91.9% of people use the Internet[1] to frequently acquire information through websites and mobile apps. As the number of homepages in charge of providing information is increasing every year, the number of applications for web vulnerability diagnosis, which diagnoses the safety of homepages, is also increasing. In the existing web vulnerability check, the number of diagnostic personnel should increase in proportion to the number of homepages that need diagnosis because the diagnosticians manually test the homepages for vulnerabilities. In reality, however, there is a limit to securing a web vulnerability diagnosis manpower, and if the number of diagnosis manpower is increased, a lot of costs are incurred. To solve these problems, an automatic diagnosis tool is used to replace a part of the manual diagnosis. This paper explores a new method to expand the current automatic diagnosis range. In other words, automatic diagnosis possible items were derived by analyzing the impact of web vulnerability diagnosis items. Furthermore, automatic diagnosis identified possible items through comparative analysis of diagnosis results by performing manual and automatic diagnosis on the website in operation. In addition, it is possible to replace manual diagnosis for possible items, but not all vulnerability items, through the improvement of automatic diagnosis tools. This paper will explore some suggestions that can help improve plans to support and implement automatic diagnosis. Through this, it will be possible to contribute to the creation of a safe website operating environment by focusing on the parts that require precise diagnosis.