• 한국공간구조학회지
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• 제1권1호
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• pp.34-42
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• 2001

The development of contemporary spatial structures for long-span roofs in China was initiated in the 19505. Space trusses, reticulated shells and cable suspended structures have been developing rapidly since 1980s. Recently there has been a growing interest in tensile membrane structures. Comprehensive theoretical study has been carried out parallel to the engineering application, which provided necessary theoretical support to the development of different types of spatial structures.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제12권4호
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• pp.237-251
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• 2005

In this paper, a new wavelet analysis of differential operator spline is generated, and it is of the symmetry and (3 -$\epsilon$ )-order regula.ity (0 < $\epsilon$ < 3). Finally, using this wavelet basis, we expand Lebesgue square integrable functions efficiently and quickly.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8271-8277
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• 2014

Aims: Apparent diffusion coefficient (ADC) values of nodes in diffusion-weighted imaging (DWI) are widely used in differentiating metastatic from non-metastatic lymph nodes. The purpose of this meta-analysis was to demonstrate whether DWI could contribute to the precise diagnosis of breast cancer (BC) with and without lymph node metastasis (LNM). Materials and Methods: English and Chinese electronic databases were searched for relevant studies followed by a comprehensive literature search. Two reviewers independently assessed the methodological quality of the included trials based on the quality assessment of diagnostic accuracy studies (QUADAS). Summary odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were calculated. Results: Final analysis of 624 BC subjects (patients with LNM = 254, patients without LNM = 370) were incorporated into the current meta-analysis from 9 eligible cohort studies. Combined ORs of ADCs suggested that ADC values in BC patients without LNM were higher than in patients with LNM (OR=0.56, 95%CI: 0.11-1.01, p=0.015). Subgroup analysis stratified by country indicated a low ADC value in BC patients with LNM rather than those without LNM among Chinese (OR=1.27, 95%CI: 0.89-1.66, p<0.001), Italians (OR=0.75, 95%CI: 0.13-1.38, p=0.018), and Egyptians (OR=1.27, 95%CI: 0.71-1.84, p<0.001). The findings of subgroup analysis by MRI machine type revealed that ADC values from diffusion MRI may be potential diagnostic indicators for BC using Non-Philips 1.5T (OR=1.10, 95%CI: 0.84-1.36, p<0.001). Conclusions: The main findings of our meta-analysis demonstrated that increased signal intensity on DWI and decreased signals on ADC are helpful in diagnosis of BC patients with or without LNM. DWI could therefore be an important imaging investigation in patients suspected of BC.

• Smart Structures and Systems
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• 제14권6호
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• pp.1247-1267
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• 2014

Real-Time Hybrid Simulation (RTHS) is a novel approach conceived to evaluate dynamic responses of structures with parts of a structure physically tested and the remainder parts numerically modelled. In RTHS, delay estimation is often a precondition of compensation; nonetheless, system delay may vary during testing. Consequently, it is sometimes necessary to measure delay online. Along these lines, this paper proposes an online delay estimation method using least-squares algorithm based on a simplified physical system model, i.e., a pure delay multiplied by a gain reflecting amplitude errors of physical system control. Advantages and disadvantages of different delay estimation methods based on this simplified model are firstly discussed. Subsequently, it introduces the least-squares algorithm in order to render the estimator based on Taylor series more practical yet effective. As a result, relevant parameter choice results to be quite easy. Finally in order to verify performance of the proposed method, numerical simulations and RTHS with a buckling-restrained brace specimen are carried out. Relevant results show that the proposed technique is endowed with good convergence speed and accuracy, even when measurement noises and amplitude errors of actuator control are present.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권4호
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• pp.1603-1623
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• 2020

Multiple Mobile Robots System (MMRS) has shown many attractive features in lots of real-world applications that motivate their rapid and wide diffusion. In MMRS, the Cooperative Localization (CL) is the basis and premise of its high-performance task. However, the statistical characteristics of the system noise should be already known in traditional CL algorithms, which is difficult to satisfy in actual MMRS because of the numerous of disturbances form the complex external environment. So the CL accuracy will be reduced. To solve this problem, an improved Adaptive Active Cooperative Localization (A²CL) algorithm based on information optimization strategy for MMRS is proposed in this manuscript. In this manuscript, an adaptive information fusion algorithm based on the variance component estimation under Extended Kalman filter (VCEKF) method for MMRS is introduced firstly to enhance the robustness and accuracy of information fusion by estimating the covariance matrix of the system noise or observation noise in real time. Besides, to decrease the effect of observation uncertainty on CL accuracy further, an observation optimization strategy based on information theory, the Model Predictive Control (MPC) strategy, is used here to maximize the information amount from observations. And semi-physical simulation experiments were carried out to verity the A²CL algorithm's performance finally. Results proved that the presented A²CL algorithm based on information optimization strategy for MMRS cannot only enhance the CL accuracy effectively but also have good robustness.

• Journal of Power Electronics
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• 제18권5호
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• pp.1315-1324
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• 2018

A novel three-phase four-wire inverter topology is presented in this paper. This topology is equipped with a special capacitor balance grid without magnetic saturation. In response to unbalanced load and unequal split DC-link capacitors problems, a qusi-full-bridge DC/DC topology is applied in the balance grid. By using a high-frequency transformer, the energy transfer within the two split dc-link capacitors is realized. The novel topology makes the voltage across two split dc-link capacitors balanced so that the neutral point voltage ripple is inhibited. Under the condition of a stable neutral point voltage, the three-phase four-wire inverter can be equivalent to three independent single phase inverters. As a result, the three-phase inverter can produce symmetrical voltage waves with an unbalanced load. To avoid forward transformer magnetic saturation, the voltages of the primary and secondary windings are controlled to reverse once during each switching period. Furthermore, an improved mode chosen operating principle for this novel topology is designed and analyzed in detail. The simulated results verified the feasibility of this topology and an experimental inverter has been built to test the power quality produced by this topology. Finally, simulation results verify that the novel topology can effectively improve the inhibition of an inverter with a three-phase unbalanced load while decreasing the value of the split capacitor.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2853-2856
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• 2012

Background: Previous studies assessing associations between matrix metalloproteinase 2 (MMP-2) polymorphisms and lung cancer risk reported conflicting results. A meta-analysis was therefore performed to derive a more precise estimation. Method: Case-control studies assessing associations between MMP-2 C735T and C1306T polymorphisms and lung cancer risk were included. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were estimated. Results: 7 studies with a total of 3,189 lung cancer cases and 3,013 controls were finally included into this meta-analysis. Overall, the MMP-2 C735T polymorphism was associated with lung cancer risk under the homozygote model (CC versus TT: OR =1.44, 95% CI = 1.03-2.02, $I^2$ = 0%), while the MMP-2 C1306T polymorphism also associated demonstrated links with all four models (all P values less than 0.05). Subgroup analyses by race suggested obvious associations between MMP-2 C735T and C1306T polymorphisms and lung cancer risk in Asians but not in Caucasians. There was no evidence for publication bias. Conclusion: Currently available evidence supports teh conclusion that MMP-2 C735T and C1306T polymorphisms influence susceptibility to lung cancer in Asians.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6643-6647
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• 2014

The breast and the thyroid are hormone responsive organs that are closely related with changes of endocrine function and glandular disease. An association between thyroid disorders and breast cancer (BC) risk has been suggested, although the results are inconclusive. The purpose of the present study was to summarize evidence supporting a relationship between BC and the level of thyroid hormones and antibodies. The MEDLINE and EMBASE electronic databases were searched for studies published between 2000 and 2014. The pooled effects were presented as weighted mean differences (WMD) with 95% confidence intervals (CI) using fixed or random effect models. We summarized the results of 8 cross-sectional studies with 4, 189 participants. The overall pooled results showed that the levels of $FT_3$ and $FT_4$ were significantly increased in patients with BC (WMD=1.592 pmol/l; 95% CI: 0.15-3.033 and WMD=0.461 ng/dl; 95% CI: 0.015-0.906; p=0.043). The TPOAb level in patients with BC was higher than that in the control group (WMD=81.4 IU/ml; 95% CI: 78.7-84.0; p=0.000). The overall pooled results of the TgAb with random effects analyses showed that the TgAb level was significantly increased in patients with BC (WMD=101.3 IU/ml; 95% CI: 48.7-153.9; p=0.000). The present results indicated that the serum levels of $FT_3$, TPOAb and TgAb are significantly higher in patients with breast cancer than in healthy controls.

• Parasites, Hosts and Diseases
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• 제55권3호
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• pp.351-355
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• 2017

Hymenolepis nana and Hymenolepis diminuta are globally widespread zoonotic cestodes. Rodents are the main reservoir host of these cestodes. Brown rats (Rattus norvegicus) are the best known and most common rats, and usually live wherever humans live, especially in less than desirable hygiene conditions. Due to the little information of the 2 hymenolepidid species in brown rats in China, the aim of this study was to understand the prevalence and genetic characterization of H. nana and H. diminuta in brown rats in Heilongjiang Province, China. Total 114 fecal samples were collected from brown rats in Heilongjiang Province. All the samples were subjected to morphological examinations by microscopy and genetic analysis by PCR amplification of the mitochondrial cytochrome c oxidase subunit 1 (COX1) gene and the internal transcribed spacer 2 (ITS2) region of the nuclear ribosomal RNA gene. In total, 6.1% (7/114) and 14.9% (17/114) of samples were positive for H. nana and H. diminuta, respectively. Among them, 7 and 3 H. nana isolates were successfully amplified and sequenced at the COX1 and ITS2 loci, respectively. No nucleotide variations were found among H. nana isolates at either of the 2 loci. Seventeen H. diminuta isolates produced 2 different COX1 sequences while 7 ITS2 sequences obtained were identical to each other. The present results of H. nana and H. diminuta infections in brown rats implied the risk of zoonotic transmission of hymenolepiasis in China. These molecular data will be helpful to deeply study intra-specific variations within Hymenolepis cestodes in the future.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1297-1303
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• 2012

Aims: Primary hepatocellular carcinoma (HCC) is a common malignancy often related to hepatitis viral infection. Smad4 is known to mediate the TGF-${\beta}$ pathway to suppress tumorigenesis. However, the function of Smad4 in HCC is still controversial. In this study we compared levels of Smad4 in HCC tissues with or without hepatitis virus infection and adjacent normal-appearing liver. Methods: Samples from HCC patients were analyzed for Smad4 protein and mRNA expression by immunohistochemistry (IHC), RT-PCR and Western blotting. Results: We found that tumor tissues expressed less Smad4 mRNA and protein than the adjacent tissues. Most HCC tumor tissues were negative for Smad4 in IHC staining, while the majority of adjacent tissues were positively stained. Interestingly, protein levels were higher in HCC tissues with viral hepatitis than those without virus infection. Suppression of expression appeared closely related to HCC, so that Smad4 appears to function as a tumor suppressor gene (TSG). Conclusion: Patients with hepatitis viral infection, at higher risk for HCC, exhibited increased Smad4 protein expression suggesting hepatitis virus may modulate Smad4 expression, which is functionally distinct from its putative role as a TSG. Smad4 expression may thus be an applicable marker for diagnosis and/or a target to develop therapeutic agents for HCC.