• 제목/요약/키워드: combine effects

검색결과 232건 처리시간 0.029초

초음파 위치인지 시스템의 간섭 문제의 해결을 위한 연구 (Toward A Totally Solving Interference Problem for Ultrasound Localization System)

  • 송병훈;함경선;이형수
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2006년도 하계종합학술대회
    • /
    • pp.177-178
    • /
    • 2006
  • The real-time tracking system is an essential factor for the development of low cost sensor networks for use in pervasive computing and ubiquitous networking. In this paper, we address the interference problems of the sensor network platform with ultrasonic for location tracking system. Ubiquitous indoor environments often contain substantial amounts of metal and other such reflective materials that affect the propagation of radio frequency signals in non-trivial ways, causing severe multi-path effects, dead-spots, noise, and interference. Especially we present a novel reducing interference location system that is particularly well suited to support context-aware computing. The system called Pharos, aims to combine the advantages of real-time tracking systems that implement distributed environment with regardless of infrastructure or infrastructure-less wireless sensor networks.

  • PDF

노인복지시설과 학교시설의 복합화 방안에 관한 연구 (A Study on the Community Complex Combining Elderly Welfare Facility with School)

  • 권순정;전성민
    • 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
    • /
    • 제14권1호
    • /
    • pp.21-30
    • /
    • 2008
  • As a result of rapid aging speed in our society, many problems related to elderly people have happened in many parts of our society. Among them, supply for elderly housing is one of the biggest problems. In downtown areas, despite of the high demand for elderly housing, there is not enough supplement of them due to the lack of real estates. Considering the situations above, this study proposes multi generation complex which combining the school and elderly welfare facility. This combination not only brings financial benefits but also has positive effects on cultural exchanges between generations. This study concentrates on finding out effective ways to combine elderly welfare facilities with community schools.

  • PDF

비약물적 분만통증 중재법에 대한 고찰 (Non-Pharmacological Interventions to Relieve Labor Pain: A Literature Review)

  • 김정수
    • 부모자녀건강학회지
    • /
    • 제14권1호
    • /
    • pp.28-35
    • /
    • 2011
  • Purpose: The aim of this study is to suggest a direction for the development of effective methods for relieving labor pain, by analyzing non-pharmacological interventions through a literature review. Methods: Collection of literature data in this study has been accomplished through theses, reports, and academic data searched on databases of the Research Information Sharing Services (Riss), PubMed, ProQuest, and the National Discovery for Science Leaders (NDSL). Results: Non-pharmacological interventions analyzed as effective in relieving labor pain, in literature published both within and outside of Korea, included: pre-delivery education, Yoga, Doula delivery care, Massage, Music therapy, Aromatherapy, Hypnosis, TENS, Sterilized water injection, and Acupuncture. Conclusion: Several different interventions have been attempted for the relief of labor pain. Since even the same intervention shows different results depending on the research method utilized, critical factors must be acknowledged that compromise the effectiveness of these methods. In addition, study of potential synergy effects of interventions that combine these various methods might also prove to be significant.

  • PDF

Mitigation of Adverse Effects of Malicious Users on Cooperative Spectrum Sensing by Using Hausdorff Distance in Cognitive Radio Networks

  • Khan, Muhammad Sajjad;Koo, Insoo
    • Journal of information and communication convergence engineering
    • /
    • 제13권2호
    • /
    • pp.74-80
    • /
    • 2015
  • In cognitive radios, spectrum sensing plays an important role in accurately detecting the presence or absence of a licensed user. However, the intervention of malicious users (MUs) degrades the performance of spectrum sensing. Such users manipulate the local results and send falsified data to the data fusion center; this process is called spectrum sensing data falsification (SSDF). Thus, MUs degrade the spectrum sensing performance and increase uncertainty issues. In this paper, we propose a method based on the Hausdorff distance and a similarity measure matrix to measure the difference between the normal user evidence and the malicious user evidence. In addition, we use the Dempster-Shafer theory to combine the sets of evidence from each normal user evidence. We compare the proposed method with the k-means and Jaccard distance methods for malicious user detection. Simulation results show that the proposed method is effective against an SSDF attack.

나이브 베이스에서의 커널 밀도 측정과 상호 정보량 (Mutual Information in Naive Bayes with Kernel Density Estimation)

  • 샹총량;유샹루;강대기
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2014년도 춘계학술대회
    • /
    • pp.86-88
    • /
    • 2014
  • 나이브 베이스가 가지는 가정은 실세계 데이터를 분류함에 있어 해로운 효과를 보이곤 한다. 이러한 가정을 완화하기 위해, 우리는 Naive Bayes Mutual Information Attribute Weighting with Smooth Kernel Density Estimation (NBMIKDE) 접근 방법을 소개한다. NBMIKDE는 애트리뷰트를 위한 스무드 커널과 상호 정보량 측정값을 기반으로 하는 어트리뷰트 가중치 기법을 조합한 것이다.

  • PDF

Taxi-demand forecasting using dynamic spatiotemporal analysis

  • Gangrade, Akshata;Pratyush, Pawel;Hajela, Gaurav
    • ETRI Journal
    • /
    • 제44권4호
    • /
    • pp.624-640
    • /
    • 2022
  • Taxi-demand forecasting and hotspot prediction can be critical in reducing response times and designing a cost effective online taxi-booking model. Taxi demand in a region can be predicted by considering the past demand accumulated in that region over a span of time. However, other covariates-like neighborhood influence, sociodemographic parameters, and point-of-interest data-may also influence the spatiotemporal variation of demand. To study the effects of these covariates, in this paper, we propose three models that consider different covariates in order to select a set of independent variables. These models predict taxi demand in spatial units for a given temporal resolution using linear and ensemble regression. We eventually combine the characteristics (covariates) of each of these models to propose a robust forecasting framework which we call the combined covariates model (CCM). Experimental results show that the CCM performs better than the other models proposed in this paper.

실질금리 결정모형에서의 구조변화분석 (Structural Change Analysis in a Real Interest Rate Model)

  • 전덕빈;박대근
    • 경영과학
    • /
    • 제18권1호
    • /
    • pp.119-133
    • /
    • 2001
  • It is important to find the equilibrium level of real interest rate for it affects real and financial sector of economy. However, it is difficult to find the equilibrium level because like the most macroeconomic model the real interest model has parameter instability problem caused by structural change and it is supported by various theories and definitions. Hence, in order to cover these problems structural change detection model of real interest rate is developed to combine the real interest rate equilibrium model and the procedure to detect structural change points. 3 equations are established to find various effects of other interest-related macroeconomic variables and from each equation, structural changes are found. Those structural change points are consistent with common expectation. Oil Crisis (December, 1987), the starting point of Economic Stabilization Policy (January, 1982), the starting point of capital liberalization (January, 1988), the starting and finishing points of Interest deregulation (January, 1992 and December, 1994), Foreign Exchange Crisis (December, 1977) are detected as important points. From the equation of fisher and real effects, real interest rate level is estimated as 4.09% (October, 1988) and dependent on the underlying model, it is estimated as 0%∼13.56% (October, 1988), so it varies so much. It is expected that this result is connected to the large scale simultaneous equations to detect the parameter instability in real time, so induces the flexible economic policies.

  • PDF

Compressive strength and mixture proportions of self-compacting light weight concrete

  • Vakhshouri, Behnam;Nejadi, Shami
    • Computers and Concrete
    • /
    • 제19권5호
    • /
    • pp.555-566
    • /
    • 2017
  • Recently some efforts have been performed to combine the advantages of light-weight and self-compacting concrete in one package called Light-Weight Self-Compacting Concrete (LWSCC). Accurate prediction of hardened properties from fresh state characteristics is vital in design of concrete structures. Considering the lack of references in mixture design of LWSCC, investigating the proper mixture components and their effects on mechanical properties of LWSCC can lead to a reliable basis for its application in construction industry. This study utilizes wide range of existing data of LWSCC mixtures to study the individual and combined effects of the components on the compressive strength. From sensitivity of compressive strength to the proportions and interaction of the components, two equations are proposed to estimate the LWSCC compressive strength. Predicted values of the equations are in good agreement with the experimental data. Application of lightweight aggregate to reduce the density of LWSCC may bring some mixing problems like segregation. Reaching a higher strength by lowered density is a challenging problem that is investigated as well. The results show that, the compressive strength can be improved by increasing the of mixture density of LWSCC, especially in the range of density under $2000Kg/m^3$.

A Comparative Study of Peer-driven and Task-driven on Reading Training

  • Luo, Derong
    • International Journal of Advanced Culture Technology
    • /
    • 제8권2호
    • /
    • pp.101-108
    • /
    • 2020
  • One difficulty in language learning is the training of reading ability. The improvement on this ability directly affects the process and effect of language learning. At the same time, there are numerous difficulties in actual learning and teaching. Depending on current research, there is two ideas that can utilize to enhance the reading efficiency of learners. One is to amend objective factors; the other is to change subjective factors. Compared with the two ideas, idiosyncratic factors are more manipulable and controllable, so it is more valuable to conduct researches on this. But among the many subjective factors, the degree of their effectiveness is not the same, so this article attempts to compare and analyze the driving effects of two important subjective factors (peer-driven and task-driven) on reading performance. The results show that both factors can have a positive impact on reading comprehension, but different in driving effects. The task-driven has obvious short-term effectiveness; while peer-driven needs to establish its long-term effect on the basis of early coordination and cooperation among team members. Therefore, in order to maximize the achievement of learning, it is necessary to combine strengths and avoid weaknesses according to the characteristics of two factors, so as to help learners improve reading ability most efficiently.

Investigation of wind actions and effects on the Leaning Tower of Pisa

  • Solari, Giovanni;Reinhold, Timothy A.;Livesey, Flora
    • Wind and Structures
    • /
    • 제1권1호
    • /
    • pp.1-23
    • /
    • 1998
  • This paper describes wind investigations for the Leaning Tower of Pisa which were conducted as part of an overall evaluation of its behaviour. Normally a short, stiff and heavy building would not be a candidate for detailed wind analyses. However, because of extremely high soil pressures developed from its inclination, there has been increasing concern that environmental loading such as wind actions could combine with existing conditions to cause the collapse of the tower. The studies involved wind assessment at the site as a function of wind direction, analysis of historical wind data to determine extreme wind probabilities of occurrence, estimation of structural properties, analytical and boundary layer wind tunnel investigations of wind loads and evaluation of the response with special concern for loads in the direction of inclination of the tower and significant wake effects from the neighboring cathedral for critical wind directions. The conclusions discuss the role of wind on structural safety, the precision of results attained and possible future studies involving field measurements aimed at validating or improving the analytical and boundary layer wind tunnel based assessments.