• 제목/요약/키워드: Single impact

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Extended Forecasts of a Stock Index using Learning Techniques : A Study of Predictive Granularity and Input Diversity

  • ;이동윤
    • Asia pacific journal of information systems
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    • 제7권1호
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    • pp.67-83
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    • 1997
  • The utility of learning techniques in investment analysis has been demonstrated in many areas, ranging from forecasting individual stocks to entire market indexes. To date, however, the application of artificial intelligence to financial forecasting has focused largely on short predictive horizons. Usually the forecast window is a single period ahead; if the input data involve daily observations, the forecast is for one day ahead; if monthly observations, then a month ahead; and so on. Thus far little work has been conducted on the efficacy of long-term prediction involving multiperiod forecasting. This paper examines the impact of alternative procedures for extended prediction using knowledge discovery techniques. One dimension in the study involves temporal granularity: a single jump from the present period to the end of the forecast window versus a web of short-term forecasts involving a sequence of single-period predictions. Another parameter relates to the numerosity of input variables: a technical approach involving only lagged observations of the target variable versus a fundamental approach involving multiple variables. The dual possibilities along each of the granularity and numerosity dimensions entail a total of 4 models. These models are first evaluated using neural networks, then compared against a multi-input jump model using case based reasoning. The computational models are examined in the context of forecasting the S&P 500 index.

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490MPa급 고장력강 탄뎀 가스메탈아크 용접부에 대한 기계적 성질과 미세조직 비교 (Comparison of Mechanical Properties and Microstructural Charateristies of Tandem GMAW Weld Metal in 490MPa Grade Steel)

  • 이희준;강성수;유금빈;배원학;문현수
    • Journal of Welding and Joining
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    • 제27권2호
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    • pp.76-81
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    • 2009
  • Tandem GMAW is one of the high performance welding process and used in many industries to increase the productivity. An evaluation is presented of the mechanical properties and microstructural characteristics of the Tandem GMAW and conventional Single GMAW welds in 30mm thickness 490MPa grade steel by comparison method. Welding sequence and bead with and hight was kept, avoiding the effect of the bead shape and welding sequence. Tension, bending, hardness and Charpy impact test results of Tandem GMAW met the requirement of specification and showed similar distribution with conventional Single GMAW. Volume fraction of ferrite phase in weld metal showed little difference between Tandem GMAW and Single GMAW

Cascaded Propagation and Reduction Techniques for Fault Binary Decision Diagram in Single-event Transient Analysis

  • Park, Jong Kang;Kim, Myoungha;Kim, Jong Tae
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제17권1호
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    • pp.65-78
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    • 2017
  • Single Event Transient has a critical impact on highly integrated logic circuits which are currently common in various commercial and consumer electronic devices. Reliability against the soft and intermittent faults will become a key metric to evaluate such complex system on chip designs. Our previous work analyzing soft errors was focused on parallelizing and optimizing error propagation procedures for individual transient faults on logic and sequential cells. In this paper, we present a new propagation technique where a fault binary decision diagram (BDD) continues to merge every new fault generated from the subsequent logic gate traversal. BDD-based transient fault analysis has been known to provide the most accurate results that consider both electrical and logical properties for the given design. However, it suffers from a limitation in storing and handling BDDs that can be increased in size and operations by the exponential order. On the other hand, the proposed method requires only a visit to each logic gate traversal and unnecessary BDDs can be removed or reduced. This results in an approximately 20-200 fold speed increase while the existing parallelized procedure is only 3-4 times faster than the baseline algorithm.

ISI and PAPR Immune IEEE 802.11p Channels Based on Single-Carrier Frequency Domain Equalizer

  • Ali, Ahmed;Dong, Wang;Renfa, Li;Eldesouky, Esraa
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권11호
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    • pp.5513-5529
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    • 2016
  • Doppler Effect is a prominent obstacle in vehicular networks, which dramatically increase the Bit-Error-Rate (BER). This problem is accompanied with the presence of the Orthogonal Frequency Division Multiplexing (OFDM) systems in which the Doppler shift interrupts the subcarriers orthogonality. Additionally, Inter-Symbol Interference (ISI) and high Peak-to-Average Power Ratio (PAPR) are likely to occur which corrupt the received signal. In this paper, the single-carrier combined with the frequency domain equalizer (SC-FDE) is utilized as an alternative to the OFDM over the IEEE 802.11p uplink vehicular channels. The Minimum Mean Squared Error (MMSE) and Zero-Forcing (ZF) are employed in order to study the impact of these equalization techniques along with the SC-FDE on the propagation medium. In addition, we aim to enhance the BER, improve the transmitted signal quality and achieve ISI and PAPR mitigation. The proposed schemes are investigated and we found that the MMSE outperforms the ZF equalization under different Doppler shift effects and modulations.

공압제어를 통한 2DOF 팽창식 관절 액추에이터 제작 (Manufacturing 2DOF Inflatable Joint Actuator by Pneumatic Control)

  • 오남수;이한얼;로드리그 휴고
    • 로봇학회논문지
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    • 제13권2호
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    • pp.92-96
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    • 2018
  • In this paper, a soft robotic arm which can prevent impact injury during human-robot interaction is introduced. Two degrees of freedom joint are required to realize free movement of the robotic arm. A robotic joint concept with a single degree of freedom is presented using simple inflatable elements, and then extended to form a robotic joint with two degrees of freedom joint using similar manufacturing methods. The robotic joint with a single degree of freedom has a joint angle of $0^{\circ}$ bending angle when both chamber are inflated at equal pressures and maximum bending angles of $28.4^{\circ}$ and $27.1^{\circ}$ when a single chamber if inflated. The robotic joint with two degrees of freedom also has a bending angle of $0^{\circ}$ in both direction when all three chambers are inflated at equal pressures. When either one or two chambers were pressurized, the robotic joint performed bending towards the uninflated chambers.

40 Gbps RZ Transmission Using Dispersion Compensation of Single-Span in Optical Transmission Links with Multi-Span of Single Mode Fiber

  • Lee, Seong-Real
    • Journal of information and communication convergence engineering
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    • 제9권1호
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    • pp.32-37
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    • 2011
  • In dispersion management (DM) and optical phase conjugation applied into optical transmission links with multi fiber spans for minimizing the impact of nonlinearity and group velocity (GVD), implementation possibility of DM using only one fiber span for pre- or postcompensation was assessed as a function of duty cycle of RZ pulse and residual dispersion per span (RDPS). It is confirmed that DM with optimal net residual dispersion (NRD) controlled by only one fiber span could be sufficiently applied into optical transmission links, though optimal NRD is more increased than that in transmission links with the general DM scheme of pre- and postcompensation. Thus, it is expected that optical transmission system is simply designed and implemented by applying the proposed DM scheme into real optical transmission links. Also, it is confirmed that the advantageous duty cycle of RZ is 0.5 and RDPS is setting to be small value for the effective transmitting wide signal wavelength range in optical links with optimal NRD controlled by only one fiber span.

Synthesis of Spatial Results to Recommend a Preferred Alternative

  • 임광섭;강신욱
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2010년도 학술발표회
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    • pp.798-802
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    • 2010
  • The integration of GIS and fuzzy MCDA(Multi-Criteria Decision Analysis) allows the engineer to determine the preferred alternative for each spatial location in the study area. The next step is to recommend to the final decision makers a single flood management alternative for the entire region. Note that if the study area is large, it might be possible to use the kind of information to recommend different alternatives for different portions of the region. However, for this study it is assumed that only a single alternative will be used. In this study, a "cost of uniformity" metric is proposed that allows decision makers to compute the impact of selecting a single alternative for the entire floodplain. This metric represents the increase in the average distance metric value as compared to the spatially diverse solution from the MCDA and GIS analysis. The results could be applied to any region of the floodplain as desired. Whether the decision makers decide to apply these calculations to the entire floodplain or to specific important regions within the floodplain, an analysis of the increases in the cost of uniformity provides an integrated way for the decision maker to rank the alternatives. This should provide an improvement in their engineering analysis.

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미혼 대학생의 자아정체감, 가족건강성 및 결혼관련 미디어 노출이 결혼관에 미치는 영향 (Ego-identity, Family strength and Media exposure Related on impact of Marital consciousness: Focused Single Man and Women in College Students)

  • 서영숙;정추영;강복희;조은하
    • 한국임상보건과학회지
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    • 제7권1호
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    • pp.1224-1231
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    • 2019
  • Purpose: This study is basic data that I can provide the guidelines in order to the single man and women of the college students have positive the marital consciousness. Method: The subjects were 180 people as single man and women recruited from 3 college located in B city. Data were collected using structured questionnaire, and analyzed with the PASW 21.0 program. Results: The result to implement stepwise regression analysis is that the media perception from the woman and family strength are affected the significant influence(p=.007, p=.015) and explanation powers were 21.2%. The ego-identity from the man is affected the significant influence and $R^2$ were 10.9%. When looking through this results of the research, the man can be affected by the internal factor and the women can know to be influenced by the external factor. Conclusion: Accordingly, through the sex custom education the man decide to family strength, the women strengthens the factor which is internal than the external factor and it is positive, it is effective to form the outlook on marriage.

Single-flap versus double-flap approach for periodontal pocket reduction in supraosseous defects: a comparative study

  • Mathala, Venkata Lakshmi;Konathala, Santosh Venkata Ramesh;Gottumukkala, Naga Venkata Satya Sruthima;Pasupuleti, Mohan Kumar;Bypalli, Vivek;Korukonda, Radharani
    • Journal of Periodontal and Implant Science
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    • 제51권4호
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    • pp.239-253
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    • 2021
  • Purpose: The single-flap approach (SFA) is a minimally invasive technique with limited mucoperiosteal flap elevation to gain access to the buccal/palatal aspects, thus limiting post-surgical complications. The purpose of the present study was to gain insights into the impact of the SFA over the double-flap approach (DFA) on periodontal flap treatment outcomes and patient compliance in terms of discomfort and time taken for surgical procedures. Methods: Twenty patients with persistent probing pocket depths of ≥5 mm were scheduled for the SFA (test site) and for the DFA (control site). All the clinical periodontal parameters were recorded at baseline, 3 months, and 6 months. Radiographic bone level (cone-beam computed tomography) was evaluated at baseline and 6 months. Patients' postoperative pain perception and wound healing were also assessed. Results: The SFA showed a significant reduction in periodontal pocket depth, gain in clinical attachment level (CAL), and gain in bone level when compared with the DFA. The SFA substantially improved wound healing and induced less postoperative pain than the DFA. Conclusions: The SFA resulted in substantial improvement in the composite outcome measures, as shown by a reduction in pocket depth with minimal gingival recession, gain in CAL, early wound healing, less postoperative discomfort, and better patient-centered outcomes.

다중 신경망을 이용한 콘크리트 강도 추정 (Prediction of Concrete Strength Using Multiple Neural Networks)

  • 이승창;임재홍
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.647-652
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    • 2002
  • In the previous study, authors presented the I-ProConS (Intelligent PREdiction system of CONcrete Strength) using artificial neural networks (ANN) that provides in-place strength information of the concrete to facilitate concrete form removal and scheduling for construction. The serious problem of the system has occured, which it cannot appropriately predict the concrete strength when the curing temperature of a curing day is changed. This is because it uses the single neural networks, which all nodes are fully connected, and thus it cannot smoothly respond for external impact. However this paper presents that the problem can be solved by multiple neural networks, which is composed of five ANNs.

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