• Smart Structures and Systems
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• 제2권2호
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• pp.189-208
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• 2006

Monitoring large-scale civil engineering structures such as offshore platforms and high-large buildings requires a large number of sensors of different types. Innovative sensor data information technologies are very extremely important for data transmission, storage and retrieval of large volume sensor data generated from large sensor networks. How to obtain the optimal sensor set and placement is more and more concerned by researchers in vibration-based SHM. In this paper, a method of determining the sensor location which aims to extract the dynamic parameter effectively is presented. The method selects the number and place of sensor being installed on or in structure by through the tolerance domain statistical inference algorithm combined with second order sensitivity technology. The method proposal first finds and determines the sub-set sensors from the theoretic measure point derived from analytical model by the statistical tolerance domain procedure under the principle of modal effective independence. The second step is to judge whether the sorted out measured point set has sensitive to the dynamic change of structure by utilizing second order characteristic value sensitivity analysis. A 76-high-building benchmark mode and an offshore platform structure sensor optimal selection are demonstrated and result shows that the method is available and feasible.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권6호
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• pp.2128-2147
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• 2021

Cognitive radio systems are being implemented recently to tackle spectrum underutilization problems and aid efficient data traffic. Spectrum sensing is the crucial step in cognitive applications in which cognitive user detects the presence of primary user (PU) in a particular channel thereby switching to another channel for continuous transmission. In cognitive radio systems, the capacity to precisely identify the primary user's signal is essential to secondary user so as to use idle licensed spectrum. Based on the inherent capability, a new spectrum sensing technique is proposed in this paper to identify all types of primary user signals in a cognitive radio condition. Hence, a spectrum sensing algorithm using improved convolutional neural network and long short-term memory (CNN-LSTM) is presented. The principle used in our approach is simulated annealing that discovers reasonable number of neurons for each layer of a completely associated deep neural network to tackle the streamlining issue. The probability of detection is considered as the determining parameter to find the efficiency of the proposed algorithm. Experiments are carried under different signal to noise ratio to indicate better performance of the proposed algorithm. The PU signal will have an associated modulation format and hence identifying the presence of a modulation format itself establishes the presence of PU signal.

• The Journal of Asian Finance, Economics and Business
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• 제7권1호
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• pp.229-238
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• 2020

A model is presented in this paper to provide understanding of the supply chain integration and supply chain information practices' impact on the manufacturing industries. The supply chain information practices play a crucial role in sharing information between the members of SC network. Thus, it is important to develop a comprehensive understanding of the differences and similarities among ISI and information management. It will allow firms to systematically evaluate and carefully choose the information strategy. The empirical findings of this research offer essential and interesting insights about what role SCI, supply chain information and Supply chain ISI play in determining Malaysia's financial performance. The theoretical gaps addressed in this study are of significant importance, since a little empirical evidence is available regarding system infrastructure and supply chain information management's effectiveness. This research provides further paths of exploring system infrastructure and information management, thereby defining the manufacturing industries' next step in SCM struggle i.e. modifying total integrated SC principle in other manufacturing firms. The Resource-based theory discovered organizational resources as an essential organizational success ingredient. Therefore, in order to recognize its potential value, internal resources, for instance, information system and management must be fully utilized.

• Steel and Composite Structures
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• 제34권2호
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• pp.241-260
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• 2020

This article presented a comprehensive model to study static buckling stability and associated mode-shapes of higher shear deformation theories of sandwich laminated composite beam under the compression of varying axial load function. Four higher order shear deformation beam theories are considered in formulation and analysis. So, the model can consider the influence of both thick and thin beams without needing to shear correction factor. The compression force can be described through axial direction by uniform constant, linear and parabolic distribution functions. The Hamilton's principle is exploited to derive equilibrium governing equations of unified sandwich laminated beams. The governing equilibrium differential equations are transformed to algebraic system of equations by using numerical differential quadrature method (DQM). The system of equations is solved as an eigenvalue problem to get critical buckling loads and their corresponding mode-shapes. The stability of DQM in determining of buckling loads of sandwich structure is performed. The validation studies are achieved and the obtained results are matched with those. Parametric studies are presented to figure out effects of in-plane load type, sandwich thickness, fiber orientation and boundary conditions on buckling loads and mode-shapes. The present model is important in designing process of aircraft, naval structural components, and naval structural when non-uniform in-plane compressive loading is dominated.

• 대한원격탐사학회지
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• 제21권5호
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• pp.405-415
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• 2005

It is difficult to classify tidal flat surface that is composed of a mixture of mud, sand, water and microphytobenthos. We used a Linear Spectral Unmixing (LSU) method for effectively classifying the tidal flat surface characteristics within a pixel. This study aims at 1) detecting algal mat using LSU in the Saemangeum tidal flats, 2) determining a suitable end-member selection method in tidal flats, and 3) find out a habitual characteristics of algal mat. Two types of end-member were built; one is a reference end-member derived from field spectrometer measurements and the other image end-member. A field spectrometer was used to measure spectral reflectance, and a spectral library was accomplished by shape difference of spectra, r.m.s. difference of spectra, continuum removal and Mann-Whitney U-test. Reference end-members were extracted from the spectral library. Image end-members were obtained by applying Principle Component Analysis (PCA) to an image. The LSU method was effective to detect microphytobenthos, and successfully classified the intertidal zone into algal mat, sediment, and water body components. The reference end-member was slightly more effective than the image end-member for the classification. Fine grained upper tidal flat is generally considered as a rich habitat for algal mat. We also identified unusual microphytobenthos that inhabited coarse grained lower tidal flats.

• Clinics in Shoulder and Elbow
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• 제16권1호
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• pp.53-57
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• 2013

목적: 임상 연구의 통계 분석에 있어서 표본수 산출의 의미와 기본 방식에 대해서 알고자 한다. 대상 및 방법: 자료의 분류, 연구 디자인 및 도출하고자 하는 결과의 성격에 따라 각기 다른 식을 적용시켜 표본수를 산출 한다. 결과: 표본수 산출은 임상 연구를 시작하기 전에 선행되어야 하며, 적절한 표본수 산출은 유의한 결론 도출에 필수 불가결하다. 결론: 표본수 산출은 에러나 작은 변수에 민감하기 때문에 특정 식에 적용시킬 때는 주의를 요한다.

• 보존과학회지
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• 제34권3호
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• pp.227-233
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• 2018

보존가가 문화재를 보존하기 위한 철학적 담론을 이해하고 보존에 대한 윤리적 태도를 갖추고 보존원칙을 실천하는 것은 문화재의 질적 수준을 결정하는 중요한 요소이다. 그러나 지금까지 이에 대한 연구는 비교적 부족하였으며, 그로 인하여 문화재 보존에 있어서 지속적으로 철학의 부재나 원칙의 부재가 문제점으로 지적되고 있다. 이에 대한 해결방안을 제시하기 위해서는 보존철학과 보존윤리에 대한 중요성과 필요성을 학술적으로 먼저 정립하는 과정이 필요하다. 본고에서는 보존철학과 보존윤리의 개념을 서술하고, 이들 간의 상관관계, 그리고 문화재 보존의 주체인 정부-학계-전문가가 해결해나가야 할 과제를 제시하였다.

• 한국도로학회논문집
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• 제16권3호
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• pp.43-50
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• 2014

PURPOSES : The dynamic modulus can be determined by applying the various theories from the Impact Resonance Testing(IRT) Method. The objective of this paper is to determine the best theory to produce the dynamic modulus that has the lowest error as the dynamic modulus data obtained from these theories(Complex Wave equation Resonance Method related to either the transmissibility loss or not, Dynamic Stiffness Resonance Method) compared to the results for dynamic modulus determined by using the Universal Testing Machine. The ultimate object is to develop the predictive model for the dynamic modulus of a Linear Visco-Elastic specimen by using the Complex Wave equation Resonance Method(CWRM) came up for an existing study(S. O. Oyadiji; 1985) and the Optimization. METHODS : At the destructive test which uses the Universal Testing Machine, the dynamic modulus results along with the frequency can be used for determining the sigmoidal master curve function related to the reduced frequency by applying Time-Temperature Superposition Principle. RESULTS : The constant to be solved from Eq. (11) is a value of 14.13. The reduced dynamic modulus obtained from the IRT considering the loss factor related to the impact transmissibility has RMSE of 367.7MPa, MPE of 3.7%. When the predictive dynamic modulus model was applied to determine the master curve, the predictive model has RMSE of 583.5MPa, MPE of 3.5% compared to the destructive test results for the dynamic modulus. CONCLUSIONS : Because we considered that the results obtained from the destructive test had the most highest source credibility in this study, the dynamic modulus data obtained respectively from DSRM, CWRM were compared to the results obtained from the destructive test by using th IRT. At the result, the reduced dynamic modulus derived from DSRM has the most lowest error.

• 무역상무연구
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• 제31권
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• pp.3-25
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• 2006

This study focus on interest for arrears and filling of the gaps left in Article 78 of CISG. In the case of CISG, Article 78 provides for interest any time a payment under a contract is untimely, but does not specify a particular rate of interest or a method to determine such a rate. This issue did not cause any uncertainty under ULIS, the CISG's antecedent, since Article 83 of ULIS provided for 1%p above the official discount rate in the creditor's country. Lacking any CISG general principle as well as any indication by the very same CISG, one can only conclude that the matter must be deferred to the domestic rule of private international law. Actually, resorting to private international law is not only admissible, but expressly required by Article 7(2). In the interpretation and filling of the gaps left in Article 78, there is a considerable difference of opinion especially amongst commentators on whether the gap is a lacuna praeter legem, i.e., one being governed by, but not expressly settled in the CISG, or whether it is an issue falling outside the scope of application of the CISG, i.e. a lacuna intra legem. The protagonists of the former view lay emphasis on the overall objective of the CISG, namely to create a uniform law, whereas the supporters of the latter view refer to the legislative history of Article 78 as the dominant principle in interpreting Article 78. Some authors believe that the issue of determining the rate of interest is not dealt with by CISG and it is, therefore, governed by the applicable domestic law, which is the subsidiary law applicable to the sales contract, since "no special connecting points seem to have developed for the entitlement to interest." In the light of the relevant case law, it seems correct to conclude that the interest rate is not determined by CISG and that courts normally determine it according to their own rules of private international law. While CISG Article 78 expressly does not deal with this issue, PICC Article 7.4.9 and PECL Article 9.508, on the other hand, set forth a precise method for computing interest. Although a method like the one set by PICC may be useful and may encourage uniformity, it still cannot be used under the CISG. The PICC or PECL formula may, however, be a very good starting point in a de jure condendum analysis when a new Article 78 will be drafted, if an interest rate method will ever be embodied in the text of an international convention.

• 해양환경안전학회지
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• 제27권5호
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• pp.557-565
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• 2021

경로추종 제어는 대양에서 선박의 자율운항을 위한 가장 기본적인 연구 중에 하나로 여겨진다. 본 연구는 선수미방향, 횡방향 및 회두방향으로 외력이 작용하는 경로추종 제어를 다룬다. 가상의 선박에서 발생하는 항로를 자선이 추종하는 문제를 해결하기 위해서 유도 원리와 백스테핑 기법을 활용하였다. 경로추종 제어에서 가장 중요한 기술 중에 하나는 오차 동역학에 관한 것으로서, 이 개념은 선박의 자동 충돌 회피 및 자동 접안 제어 등과 같은 연구 영역에서도 활용이 가능하다. 유도 원리와 오차 변수의 알고리즘은 수치 시뮬레이션을 통해 증명하였다. 그 결과, 회두각의 오차를 제외한 대부분의 오차 변수는 제어기를 통하여 제로 값으로 수렴하였다. 기존에 근거리 통항선박의 간섭력을 고려한 안전통항거리의 값보다 두 선박 간의 경로추종 제어의 트래킹 오차의 값이 더 작은 점이 가장 흥미로운 결과 중에 하나로 여겨진다. 또한 프로펠러, 핀이나 러더와 같은 엑츄에이터의 손상을 줄이기 위해서는 수렴의 성능과 선박의 안전을 절충하여 적합한 제어 파라미터를 결정할 필요가 있다.