• Journal of applied mathematics & informatics
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• v.25 no.1_2
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• pp.155-167
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• 2007

A graph G is called to be a 2-degree integral subgraph of a q-tree if it is obtained by deleting an edge e from an integral subgraph that is contained in exactly q - 1 triangles. An added-vertex q-tree G with n vertices is obtained by taking two vertices u, v (u, v are not adjacent) in a q-trees T with n - 1 vertices such that their intersection of neighborhoods of u, v forms a complete graph $K_{q}$, and adding a new vertex x, new edges xu, xv, $xv_{1},\;xv_{2},\;{\cdots},\;xv_{q-4}$, where $\{v_{1},\;v_{2},\;{\cdots},\;v_{q-4}\}\;{\subseteq}\;K_{q}$. In this paper we prove that a graph G with minimum degree not equal to q - 3 and chromatic polynomial $$P(G;{\lambda})\;=\;{\lambda}({\lambda}-1)\;{\cdots}\;({\lambda}-q+2)({\lambda}-q+1)^{3}({\lambda}-q)^{n-q-2}$$ with $n\;{\geq}\;q+2$ has and only has 2-degree integral subgraph of q-tree with n vertices and added-vertex q-tree with n vertices.

• Korean Journal of Bronchoesophagology
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• v.2 no.1
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• pp.46-56
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• 1996

Perichondrium is generally used for reconstruction of airway and successful regeneration of cartilage framework using perichondrium are reported by several authors. It has many advantages for airway reconstruction. It can maintain the stable framework and it has higher flexibility so it's easy to design according to the shape of defects. It resist strongly against infection process. Its airtightness and rapid mucosalization enables to predict good postoperative recovery and results. To investigate the differences in cartilage regeneration between avascular and vascularized perichondrial flap, this study was designed with vascularized flaps composed of vascularized perichondrium and central auricular artery and vein. Morphologic study was performed to determine the fate of the grafted perichondrium at regular intervals using light microscopy with H & E stain. Chondrogenic potential and formation of cartilaginous plate of experimental group was superior than in the control group. Grafted perichondrium was fed by consistent feeding vessel. At 6 weeks, the regenerated cartilage could hardly be distinguished form the normal cartilage framework but in control group, regenerated cartilaginous tissue was generally immature in same period. In conclusion, this study indicated that consistent vasculature to grafed tissue is the essential factor for successful reconstruction of cartilaginous framework.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.17 no.2
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• pp.79-90
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• 2006

Social deficits are the most critical and core deficits of the children with Autistic Spectrum Disorder(ASD) and they are qualitatively as well as qualitatively different from typically developing children. It is proposed that the attachment between the mother and the autistic child should be promoted foremost and early as possible, to improve social deficits, just like early social developments in normal children depend largely on interactions between the mother and the child who are attached to each other we have developed an interventional program, 'Attachment Promotion Therapy', largely based on the attachment theory. The Attachment promotion Therapy mandates the participation of both the mother and the autistic child, and consists of mutually enjoying play activities, close physical contacts and parental training on intense mother-child interactions, focusing on improving maternal sensitivity, responsiveness, and nurturing behaviors during their interactions. The program was found to be effective in improving attachment behaviors, attachment security and acquiring joint attention skills. Attachment Promotion Therapy is therefore proposed here as the important earliest intervention method for children with ASD and could become the base for many other educational and therapeutic interventions.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.298-302
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• 2009

We investigated the anti-obesity effect of berberine in mice fed a high fat diet and focused on the analysis of adipogenesis in epdidymal adipose tissue. Male C57BL/6J mice were divided into three groups, which were fed either a normal diet (Nor), a high fat diet (HFD), or a high fat diet plus orally administered berberine (0.2 g /kg body weight) (HFD+B) for 8 weeks. Relative to mice in the HFD group, mice in the HFD+B group showed significant reductions in weight gain and adipose tissue weight. Serum triglyceride levels in mice from the HFD+B group were significantly lower than those of the HFD mice, as were the levels of serum insulin and leptin. An effect of berberine to reduce epididymal adipose mass was revealed by H&E staining. Berberine inhibited the high fat diet-induced increase in levels of the proteins CD36 and CCAAT/enhancer-binding protein $\alpha$ ($C/EBP{\alpha}$) observed in epididymal adipose tissues of mice from the HFD group. These results suggest that berberine has an anti-obesity effect in mice and that the effect is mediated by inhibition of adipogenesis.

• The KIPS Transactions:PartC
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• v.10C no.3
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• pp.253-264
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• 2003

This paper presents the analytic model of Distributed Denial-of-Service (DDoS) attacks in two settings: the normal Web server without any attack and the Web server with DDoS attacks. In these settings, we measure TCP flag rate, which is expressed in terms of the ratio of the number of TCP flags, i.e., SYN, ACK, RST, etc., packets over the total number of TCP packets, and Protocol rate, which is defined by the ratio of the number of TCP (UDP or ICMP) packets over the total number of W packets. The experimental results show a distinctive and predictive pattern of DDoS attacks. We wish our approach can be used to detect and prevent DDoS attacks.

• Structural Engineering and Mechanics
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• v.39 no.6
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• pp.833-847
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• 2011

We have developed a lightweight aggregate (LWA) concrete made by expanding fine sediments dredged from the Shihmen Reservoir (Taiwan) with high heat. In this study, the performance of the concrete and of prestressed concrete beams made of the sedimentary LWA were tested and compared with those made of normal-weight concrete (NC). The test results show that the lightweight concrete (LWAC) exhibited comparable time-dependent properties (i.e., compressive strength, elastic modulus, drying shrinkage, and creep) as compared with the NC samples. In addition, the LWAC beams exhibited a smaller percentage of prestress loss compared with the NC beams. Moreover, on average, the LWAC beams could resist loading up to 96% of that of the NC beams, and the experimental strengths were greater than the nominal strengths calculated by the ACI Code method. This investigation thus established that sedimentary LWA can be recommended for structural concrete applications.

• Structural Engineering and Mechanics
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• v.14 no.6
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• pp.679-698
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• 2002

In this paper some techniques for the dynamic analysis of non-classically damped linear systems are reviewed and compared. All these methods are based on a transformation of the governing equations using a basis of complex or real vectors. Complex and real vector bases are presented and compared. The complex vector basis is represented by the eigenvectors of the complex eigenproblem obtained considering the non-classical damping matrix of the system. The real vector basis is a set of Ritz vectors derived either as the undamped normal modes of vibration of the system, or by the load dependent vector algorithm (Lanczos vectors). In this latter case the vector basis includes the static correction concept. The rate of convergence of these bases, with reference to a parametric structural system subjected to a fixed spatial distribution of forces, is evaluated. To this aim two error norms are considered, the first based on the spatial distribution of the load and the second on the shear force at the base due to impulsive loading. It is shown that both error norms point out that the rate of convergence is strongly influenced by the spatial distribution of the applied forces.

• Structural Engineering and Mechanics
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• v.28 no.1
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• pp.53-67
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• 2008

Anisotropic materials are increasingly required in modern technological applications. Certainly, civil, mechanical and naval engineers frequently deal with the situation of analyzing the dynamical behaviour of structural elements being composed of such materials. For example, panels of anisotropic materials must sometimes support electromechanical engines, and besides, holes are performed in them for operational reasons e.g., conduits, ducts or electrical connections. This study is concerned with the natural frequencies and normal modes of vibration of rectangular anisotropic plates supported by different combinations of the classical boundary conditions: clamped, simply - supported and free, and with additional complexities such holes of free boundaries and attached concentrated masses. A variational approach (the well known Ritz method) is used, where the displacement amplitude is approximated by a set of beam functions in each coordinate direction corresponding to the sides of the rectangular plate. Consequently each coordinate function satisfies the essential boundary conditions at the outer edge of the plate. The influence of the position and magnitude of both hole and mass, on the natural frequencies and modal shapes of vibration are studied for a generic anisotropic material. The classical Ritz method with beam functions as spatial approximation proved to be a suitable procedure to solve a problem of such analytical complexity.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.28 no.3
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• pp.124-131
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• 2016

In this study, a physical experiment was performed to investigate the change in the stability coefficient, defined by Hudson equation, for the tetrapod of different specific densities. The experiment was carried out once (with no repetition) for a rubble mound breakwater with 1:1.5 slope. In this experiment, the stability coefficient for the high-density tetrapod was greater than that for the normal-density tetrapod. This indicates variability of the stability coefficient according to change in the density of tetrapod. Further experiments and detailed analysis are required to investigate the effect of the density on the stability coefficient of tetrapod.

• Journal of Power Electronics
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• v.15 no.3
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• pp.670-684
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• 2015

The hybrid cascaded multilevel inverter (HCMLI) is a popular converter topology that is being increasingly used in high power medium voltage drives. The intricacy of the control technique for a HCMLI increases with the number of levels and due to fluctuating dc voltages. This paper presents a novel offline quadrant search based space vector modulation technique to synthesize a sinusoidal output from a dispersed pattern of voltage vectors due to different voltages in the auxiliary unit. Such an investigation has never been reported in the literature and it is being attempted for the first time. The method suggested distributes the voltage vectors for a reduced total harmonic distortion at minimal computation. In addition, the proposed algorithm determines the maximum modulation index in the linear modulation range in order to synthesize a sinusoidal output for both normal and abnormal vector patterns. It is better suited for a wide range of practical applications. It is particularly well suited for renewable source fed inverters which utilize large capacitor banks to maintain the dc link, which are prone to such slow fluctuations. The proposed quadrant search space vector modulation technique is simulated using MATLAB/SIMULINK and implemented using a Nexys-2 Spartan-3E FPGA for a developed prototype.