Research on the Effects of Boundary Element Characteristics on Reconstruction Accuracy by BEM-based NAH

Hai-Bin Zhang,Yang-Hann Kim,Wei-Kang Jiang 한국소음진동공학회 2012 한국소음진동공학회 학술대회논문집 Vol.2012 No.10

Nearfield acoustic holography method predicts an unmeasured sound field, therefore it depends on its prediction methods. In particular, if one has radiators or scatters, which cannot be expressed by simple geometry, then inverse boundary element method (BEM) is normally employed to reconstruct the sound field induced by sound sources with irregular profiles. The characteristics of boundary element, including the element shape, characteristic length, order of shape function and others, affect the reconstruction error. Investigating the errors by means of changing these factors will provide a guide line for selecting appropriate factors, associated with the elements of BEM. These factors are investigated by numerical simulations, and the accuracies with respect to the variant factors are compared. Novel suggestions for selecting appropriate boundary element factors are described based on the simulation results.

Structural Characterization and Optical Properties of Sol-gel-derived Polycrystalline Pb(Zr0.35Ti0.65)O3 Thin Films

Fan Zhang,Rong-Jun Zhang,Zi YiWang,Yu-Xiang Zheng,Song-You Wang,Hai-Bin Zhao,Liang-Yao Chen,Xiao Bin Liu,An Quan Jiang 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.1

Polycrystalline Pb(Zr0.35Ti0.65)O3 thin films prepared on Pt/Ti/SiO2/Si substrate by using solgel technique were characterized by using X-ray diffraction (XRD) and atomic force microscopy (AFM). The optical properties of the films were investigated by using spectroscopic ellipsometry (SE) with a four-phase optical model, air/roughness layer/PZT layer/Pt layer in the spectral range of 300 - 800 nm. The optical band gap of the films calculated following the Tauc’s Law was smaller than that of an amorphous PZT thin film with some microcrystals existing on the surface. The result indicates that the quantum-size effect leads to an increase in band gap when the crystalline dimensions become very small.

Construction and Characterization of Vitreoscilla Hemoglobin (VHb) with Enhanced Peroxidase Activity for Efficient Degradation of Textile Dye

( Zi Dong Zhang ),( Wei Li ),( Hai Chao Li ),( Jing Zhangi ),( Yue Bin Zhang ),( Yu Feng Cao ),( Jian Zhang Ma ),( Zheng Qiang Li ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.9

Pollution resulting from the discharge of textile dyes into water systems has become a major global concern. Because peroxidases are known for their ability to decolorize and detoxify textile dyes, the peroxidase activity of Vitreoscilla hemoglobin (VHb) has recently been studied. It is found that VHb and variants of this enzyme show great promise for enzymatic decolorization of dyes and may play a role in achieving their successful removal from industrial wastewater. The level of VHb peroxidase activity correlates with two amino acid residues present within the conserved distal pocket, at positions 53 and 54. In this work, sitedirected mutagenesis of these residues was performed and resulted in improved VHb peroxidase activity. The double mutant, Q53H/P54C, shows the highest dye decolorization and removal efficiency, with 70% removal efficiency within 5 min. UV spectral studies of Q53H/P54C reveals a more compact structure and an altered porphyrin environment (λSoret = 413 nm) relative to that of wild-type VHb (λSoret = 406), and differential scanning calorimetry data indicate that the VHb variant protein structure is more stable. In addition, circular dichroism spectroscopic studies indicate that this variant’s increased protein structural stability is due to an increase in helical structure, as deduced from the melting temperature, which is higher than 90°C. Therefore, the VHb variant Q53H/P54C shows promise as an excellent peroxidase, with excellent dye decolorization activity and a more stable structure than wild-type VHb under high-temperature conditions.

Impact of Adjuvant Chemotherapy Cycles on Prognosis of Resectable Stomach Cancer: A Retrospective Analysis

Zhang, Wen-Ying,Zhang, Wen-Jun,Bai, Yu,Yuan, Hai-Hua,Liu, Feng,Gao, Jun,Gong, Yan-Fang,Jiang, Bin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Aims: The aim of this study was to investigate the effects of adjuvant chemotherapy cycles on the prognosis of patients with post-operative stomach cancer through retrospective analysis. Methods: A total of 128 patients with gastric cancer who underwent gastrectomy, followed by adjuvant chemotherapy consisting of epirubicin, cisplatin or oxaliplatin, leucovorin, and 5-fluorouracil, according to a defined schedule, were divided into three groups according to the number of chemotherapy cycles: Group I (<6 cycles); Group II (6 cycles); and Group III (>6 cycles). Results: The 5-year overall survival (OS) was 20.8% in Group I, 45.0% in Group II, and 42.9% in Group III, with a median follow-up of 43 months. The 5-year relapse-free survival (RFS) was 15.1% in Group I, 40% in Group II, and 40% in Group III. The OS and RFS in Groups II and III were significantly better than in Group I (OS, p = 0.002 and p=0.003; RFS, P<0.001 and P=0.002). There was no difference in OS (p = 0.970) or in RFS (p = 0.722) between Groups II and III. Multivariate Cox hazard analysis determined that the number of adjuvant chemotherapy cycles was an independent factor that influenced OS and RFS. Conclusion: Six cycles of adjuvant chemotherapy gave encouraging outcomes in patients with resectable gastric cancer. Further prospective randomized controlled investigations are warranted in a multi-center setting.

Decision on Quality Investment Level Under Moral Hazard Environment

Zhang, Cui-Hua,Yu, Hai-Bin The Korean Society for Quality Management 2007 The Asian Journal on Quality Vol.8 No.2

Moral hazard and adverse selection often exist in asymmetric information environment. In this paper, quality investment decision problem is studied under moral hazard. A basic model for quality investment level decision is developed with the supplier as a principal and the buyer as an agent. And then we regard the supplier and the buyer's rational limitations to set up a model when the buyer's quality evaluation and processing activities are hidden. The model is optimized and the results under different backgrounds are discussed and compared. Results show that the buyer's quality evaluation level and processing level are mostly influenced by the supplier's quality assurance payment. Both the supplier and the buyer choose different quality investment levels under moral hazard because of the supplier's payment to the buyer in case of internal failure and external failure.

VHL Gene Mutation Analysis of a Chinese Family with Non-Syndromic Pheochromocytomas and Patients with Apparently Sporadic Pheochromocytoma

Zhang, Bin,Qian, Jing,Chang, De-Hui,Wang, Yang-Min,Zhou, Da-Hai,Qiao, Gou-Mei Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

Objective: The Von Hippel-Lindau syndrome (VHLD), an inherited neoplastic syndrome predisposing to central nervous system hemangioblastoma (CNS), pheochromocytoma (PCC), renal cell carcinoma(RCC), retinal hemangioma (RA) and renal cysts, is caused by mutations or deletions of the VHL tumor-suppressor gene. To assess VHL genotype-phenotype correlations with function of pVHL a gene mutation analysis of members in a Chinese family with non-syndromic PCCs and individuals with apparently sporadic pheochromocytoma (ASP) was performed. Materials and Methods: DNA samples of 20 members from the Chinese family with non-syndromic PCCs and 41 patients with ASP were analyzed by polymerase chain reaction and direct sequencing, confirmed by Taqman probe. Results: Three novel mutations (H125P, 623(^TTTGTtG) and R120T) were identified in the Chinese family and in 3 among 41 ASP patients. The mutations were all located in exon 2 of VHL gene encoding ${\beta}$-domain of pVHL. The tumor type in H125P carriers and R120T carriers was VHL type 2C. And 623(^TTTGTtG) carriers presented VHL type 2B or type 2C. Conclusions: VHL gene abnormalities were identified in the Chinese family with non-syndromic PCCs and patients with APS, resulting in dysfunction of pVHL. H125P and R120T could be associated with VHL type 2C, while 623(^TTTGTtG) might be linked with VHL type 2B or type 2C. Not only is the genetic analysis helpful for early diagnosis and treatment of patients with VHLD, it is also benefitial for research intoVHLD pathogenesis.

Comparison of the efficacy and safety of transurethral laser versus open prostatectomy for patients with large-sized benign prostatic hyperplasia: A meta-analysis of comparative trials

Hai-bin Wei,Bing-yi Guo,Yao-fen Tu,Xuan-han Hu,Wei Zheng,Da-hong Zhang,Jian Zhuo 대한비뇨의학회 2022 Investigative and Clinical Urology Vol.63 No.3

Purpose: The selection of open prostatectomy (OP) over transurethral laser surgery is controversial for large volume prostates. Thus, we aim to compare the efficacy and safety of transurethral laser versus OP, and provide the latest evidence of clinical practice for large-sized benign prostatic hyperplasia (BPH). Materials and Methods: This meta-analysis used Review Manager V5.3 software and the systematic literature search of Cochrane Library, Embase, PubMed, and Web of Science datasets was performed for citations published from 2000 to 2020 that compared transurethral laser with OP for the treatment of large BPH. Variables of interest assessing the two techniques included clinical characteristics, and the perioperation-, effectiveness-, and complication-related outcomes. Results: The meta-analysis included twelve studies containing 1,514 patients, with 792 laser and 722 OP. The transurethral laser group was associated with shorter hospital stay and catheterization duration, and less hemoglobin decreased in the perioperative variables. There was no significant difference in the international prostate symptom score, post-void residual urine volume, maximum flow rate, and quality of life score. Transurethral laser group had a significantly lower incidence of blood transfusion than OP group (odds ratio, 0.10; 95% confidence interval, 0.05 to 0.19; p<0.001; I2=8%), and no statistical differences were found with respect to the other complications. Conclusions: Both OP and transurethral laser prostatectomy are effective and safe treatments for large prostate adenomas. With these advantages of less blood loss and transfusion, and shorter catheterization time and hospital stay, laser may be a better choice for large BPH.

Non-conservative Characteristics of Seawater Calcium Ion in Offshore Aquaculture Areas: A Case Study in the Muping Marine Ranch, Yantai, China

Zhang Zhe,Bian Hai-Zhen,Hu Yu-Bin 한국해양과학기술원 2023 Ocean science journal Vol.58 No.3

Calcium ( Ca2+) is a major ion in the ocean, and its ratio to salinity is generally considered to be relatively constant. However, its conservativeness is often compromised in offshore waters, particularly in marine shellfish cultured areas, where the Ca2+ concentration could be affected by biological activities. Therefore, a deviation might occur in evaluating ocean acidification in an aquaculture area when the aragonite saturation (Ωarag) is calculated based on the Ca2+ concentration via the calciumsalinity ratio. This study measured the Ca2+ concentration, and explored the distribution of Ca2+ and the causes of excess calcium ( Ca2+ excess) as well as the degree of acidification based on a field survey from 2020 to 2021 in the Muping Marine Ranch, Yantai. The results showed that the Ca2+ concentrations in both surface and bottom seawater and vertical differences were higher in summer than in other seasons. The measured Ca2+ concentrations in seawater were on average 0.372 mmol/ kg higher than those calculated by the calcium-salinity ratio. The riverine input was the leading cause for the formation of Ca2+ excess, which was reduced to some extent by the activity of cultured calcifying organisms. The Ωarag obtained from the measured Ca2+ was on average 0.10 higher than that derived from the calculated Ca2+ via the calcium-salinity ratio, indicating that the ocean acidification level might be somewhat overestimated if Ωarag is derived from the calculated Ca2+ in coastal areas, especially in estuarine environments that are heavily influenced by riverine input. Therefore, the investigation of the non-conservative characteristics of Ca2+ in offshore seawater should help to accurately assess the acidification level of aquaculture areas.

A Monocular Structured Light Vision Method for Pose Determination of Large Non-cooperative Satellites

Bin Liang,Xue-Hai Gao,Le Pan,Zhi-Heng Li,Ying-Chun Zhang 제어·로봇·시스템학회 2016 International Journal of Control, Automation, and Vol.14 No.6

A space robotic system is expected to perform on-orbit servicing missions to rescue malfunctionedsatellites in geostationary orbit (GEO). In final berthing and capture, it is difficult for a space robot to determine therelative pose (attitude and position) of a non-cooperative malfunctioned satellite that is usually huge and withoutartificial recognition devices. In this paper, a space robot with a monocular structured light vision subsystem isintroduced to solve the problem. Firstly, the monocular structured light vision subsystem composed of a singlecamera and a point light source is designed. Secondly, a partial rectangular shaped framework, which is verycommon on a non-cooperative malfunctioned satellite, is chosen as the recognition object for non-cooperative posemeasurement. Using projection constraints on rectangle and circular points, a rectangle feature reconstructionalgorithm is proposed. Thirdly, according to the reconstructed rectangle feature, a least square method of posedetermination is presented. Lastly, using a semi-physical vision simulation system, several experiments of typicalcases are simulated to verify the pose determination method of large non-cooperative target. The results show thevalidity and flexibility of the proposed method.

Atomistic simulations of defect accumulation and evolution in heavily irradiated titanium for nuclear-powered spacecraft

Guopeng Zhang,Bin Cai,Hai Huang,Xiaoting Yuan,Longjingrui Ma,Jiwei Lin Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.6

Titanium alloys are expected to become one of the candidate materials for nuclear-powered spacecraft due to their excellent overall performance. Nevertheless, atomistic mechanisms of the defect accumulation and evolution of the materials due to long-term exposure to irradiation remain scarcely understood by far. Here we investigate the heavy irradiation damage in a-titanium with a dose as high as 4.0 canonical displacements per atom (cDPA) using atomistic simulations of Frenkel pair accumulation. Results show that the content of surviving defects increases sharply before 0.04 cDPA and then decreases slowly to stabilize, exhibiting a strong correlation with the system energy. Under the current simulation conditions, the defect clustering fraction may be not directly dependent on the irradiation dose. Compared to vacancies, interstitials are more likely to form clusters, which may further cause the formation of 1/3<1210> interstitial-type dislocation loops extended along the (1010) plane. This study provides an important insight into the understanding of the irradiation damage behaviors for titanium.