RADIUS OF FULLY STARLIKENESS AND FULLY CONVEXITY OF HARMONIC LINEAR DIFFERENTIAL OPERATOR

Liu, ZhiHong,Ponnusamy, Saminathan Korean Mathematical Society 2018 대한수학회보 Vol.55 No.3

Let $f=h+{\bar{g}}$ be a normalized harmonic mapping in the unit disk $\mathbb{D}$. In this paper, we obtain the sharp radius of univalence, fully starlikeness and fully convexity of the harmonic linear differential operators $D^{\epsilon}{_f}=zf_z-{\epsilon}{\bar{z}}f_{\bar{z}}({\mid}{\epsilon}{\mid}=1)$ and $F_{\lambda}(z)=(1-{\lambda)f+{\lambda}D^{\epsilon}{_f}(0{\leq}{\lambda}{\leq}1)$ when the coefficients of h and g satisfy harmonic Bieberbach coefficients conjecture conditions. Similar problems are also solved when the coefficients of h and g satisfy the corresponding necessary conditions of the harmonic convex function $f=h+{\bar{g}}$. All results are sharp. Some of the results are motivated by the work of Kalaj et al. [8].

Array comparative genomic hybridization screening in IVF significantly reduces number of embryos available for cryopreservation

Liu, Jiaen,Sills, E. Scott,Yang, Zhihong,Salem, Shala A.,Rahil, Tayyab,Collins, Gary S.,Liu, Xiaohong,Salem, Rifaat D. The Korean Society for Reproductive Medicine 2012 Clinical and Experimental Reproductive Medicine Vol.39 No.2

Objective: During IVF, non-transferred embryos are usually selected for cryopreservation on the basis of morphological criteria. This investigation evaluated an application for array comparative genomic hybridization (aCGH) in assessment of surplus embryos prior to cryopreservation. Methods: First-time IVF patients undergoing elective single embryo transfer and having at least one extra non-transferred embryo suitable for cryopreservation were offered enrollment in the study. Patients were randomized into two groups: Patients in group A (n=55) had embryos assessed first by morphology and then by aCGH, performed on cells obtained from trophectoderm biopsy on post-fertilization d5. Only euploid embryos were designated for cryopreservation. Patients in group B (n=48) had embryos assessed by morphology alone, with only good morphology embryos considered suitable for cryopreservation. Results: Among biopsied embryos in group A (n=425), euploidy was confirmed in 226 (53.1%). After fresh single embryo transfer, 64 (28.3%) surplus euploid embryos were cryopreserved for 51 patients (92.7%). In group B, 389 good morphology blastocysts were identified and a single top quality blastocyst was selected for fresh transfer. All group B patients (48/48) had at least one blastocyst remaining for cryopreservation. A total of 157 (40.4%) blastocysts were frozen in this group, a significantly larger proportion than was cryopreserved in group A (p=0.017, by chi-squared analysis). Conclusion: While aCGH and subsequent frozen embryo transfer are currently used to screen embryos, this is the first investigation to quantify the impact of aCGH specifically on embryo cryopreservation. Incorporation of aCGH screening significantly reduced the total number of cryopreserved blastocysts compared to when suitability for freezing was determined by morphology only. IVF patients should be counseled that the benefits of aCGH screening will likely come at the cost of sharply limiting the number of surplus embryos available for cryopreservation.

Radius of fully starlikeness and fully convexity of harmonic linear differential operator

ZhiHong Liu,Saminathan Ponnusamy 대한수학회 2018 대한수학회보 Vol.55 No.3

Let $f=h+\overline{g}$ be a normalized harmonic mapping in the unit disk $\ID$. In this paper, we obtain the sharp radius of univalence, fully starlikeness and fully convexity of the harmonic linear differential operators $D_f^{\epsilon}=zf_{z}-\epsilon\overline{z}f_{\overline{z}}~(|\epsilon|=1)$ and $F_{\lambda}(z)=(1-\lambda)f+\lambda D_f^{\epsilon}~(0\leq\lambda\leq 1)$ when the coefficients of $h$ and $g$ satisfy harmonic Bieberbach coefficients conjecture conditions. Similar problems are also solved when the coefficients of $h$ and $g$ satisfy the corresponding necessary conditions of the harmonic convex function $f=h+\overline{g}$. All results are sharp. Some of the results are motivated by the work of Kalaj et al. \cite{Kalaj2014}.

Asymmetric Key Pre-distribution Scheme for sensor networks

Zhihong Liu,Jianfeng Ma,Qiping Huang,SangJae Moon IEEE 2009 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS Vol.8 No.3

<P>A key pre-distribution scheme is a method by which initially an off-line trusted authority distributes pieces of information among a set of users. Later, each member of a group of users can compute a common key for secure communication. In this paper we present an asymmetric key pre-distribution scheme. Instead of assuming that the network is comprised entirely of identical users in conventional key pre-distribution schemes, the network now consists of a mix of users with different missions, i.e., ordinary users and keying material servers. A group of users, using secret keys preloaded in their memory and public keying material retrieved from one keying material server, can compute a session key. The properties of this method are that, the compromise of keying material servers does not reveal any information about users' secret keys and the session keys of privileged subset of users; if computational assumptions are considered, each user has very low storage requirement. These properties make it attractive for sensor networks. We first formally define the asymmetric key pre-distribution scheme in terms of the entropy and give lower bounds on user's storage requirement and the public keying material size. Then, we present its constructions and applications for sensor networks.</P>

Synthesis of two kinds of phenolphthalein oligomers

Zhihong Liu,Honghua Wang,Tianlu Chen 한국고분자학회 2006 한국고분자학회 학술대회 연구논문 초록집 Vol.2006 No.10

Intermetallic Compounds (IMCs) Formation in Al/Mg Dissimilar Alloy Solid State Joining: Experimental Study and Phase Field Modeling

Kuijing Song,Xinquan Liu,Yukai Ji,Yong Wei,Junrui Luo,Fei Liu,Dashuang Liu,Zhihong Zhong 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.4

Aluminum/magnesium (Al/Mg) alloys have good metallurgical compatibility as well as similar melting and recrystallizationtemperatures. Therefore, the formation of deleterious IMCs is considered as a major problem in dissimilar Al/Mgalloys joining. In this paper, the metallurgical reaction behavior and atomic diffusion in Al/Mg solid state joining interfaceare studied. Based on the thermodynamic, kinetic and crystallographic characteristics of ordered phase transformation andatomic diffusion database, a phase field calculation framework of the polycrystalline β–Al3Mg2 and γ–Al12Mg17 evolutionis developed. Diffusivity, D and interface mobility, M, which significant kinetic parameters are defined as alloy compositionsand joining conditions dependent. By a series of simulation, it is proved the simulated interdiffusion microstructuralcharacteristics and element distribution across the joining interface are in coincidence with the corresponding experimentaldata. The thermally activated IMC evolution in diffusion bonding is in thermodynamic equilibrium, while accelerated IMCevolution in friction stir welding results from thermomechanically activated D and M. The present study contributes to theunderstanding of interfacial microstructures evolution in solid state joining of dissimilar alloys.

Titanium Oxide Film : A New Biomaterial For Artificial Heart Valve Prepared by Ion Beam Enhanced Deposition

Liu, Xianghuai,Zhang, Feng,Zheng, Zhihong,Huang, Nan The Korean Vacuum Society 1997 Applied Science and Convergence Technology Vol.6 No.1

Titanium oxide films were prepared by ion beam enhanced deposition where the films were synthesized by deposition titianium atoms and simultaneously bombarding with xenon ion beam at an energy of 40 keV in an $O_2$ environ,ent. Structure and composition of titanium oxide films were investigated by X-ray Doffractopm (XRD) Ritjerfprd Backscattering Spectroscopy (RBS) and X-ray Diffraction(XRD) Rutherford Backscattering Spectroscopy (RBS) and X-ray photoelectron spectroscopy (XPS) The results show that thestructure of the prepared films exhibit a rutile phase structure wit high(200) orientation and the O/Ti ratio of the titanium oxide films was about 2:1 XPS anlysis shows that $Ti^{2+},Ti^{3+}\;and\;Ti^{4+}$ chemical states exist on the titanium oxide films. the blood compatibility of the titanium oxide films was studied by measurements of blood clotting time and platelet adhesion. The results show that the anticoagulation property of titanium oxide films improved significantly and better than that of LTI-carbon which was widely used to fabricate artificial heart valve.

A Common Bitmap Block Truncation Coding for Color Images Based on Binary Ant Colony Optimization

( Zhihong Li ),( Qiang Jin ),( Chin-chen Chang ),( Li Liu ),( Anhong Wang ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.5

For the compression of color images, a common bitmap usually is generated to replace the three individual bitmaps that originate from block truncation coding (BTC) of the R, G and B channels. However, common bitmaps generated by some traditional schemes are not the best possible because they do not consider the minimized distortion of the entire color image. In this paper, we propose a near-optimized common bitmap scheme for BTC using Binary Ant Colony Optimization (BACO), producing a BACO-BTC scheme. First, the color image is compressed by the BTC algorithm to get three individual bitmaps, and three pairs of quantization values for the R, G, and B channels. Second, a near-optimized common bitmap is generated with minimized distortion of the entire color image based on the idea of BACO. Finally, the color image is reconstructed easily by the corresponding quantization values according to the common bitmap. The experimental results confirmed that reconstructed image of the proposed scheme has better visual quality and less computational complexity than the referenced schemes.

Experimental Study on Flexural Behavior of Strengthened Corrugated Steel Plate

Baodong Liu,Fang Li,Haibo Sun,Zhihong Wang 한국강구조학회 2022 International Journal of Steel Structures Vol.22 No.1

Experimental study was conducted to verify the fl exural strength of corrugated steel plate (CSP) for various types of reinforcement which include without stiff ening ribs, with diff erent thicknesses of additional steel ribs, and with steel ribs fi lled with concrete. The test results showed that the fl exural strength of the strengthening structure of the additional steel plate using the same CSP as the main steel plate was more than 2 times that of the single CSP, and fl exural strength of the concrete-fi lled corrugated plates showed at least 3.3 times higher fl exural strength compared to the strength of single CSP. According to the force performance of the CSP strengthening structures, the nominal bearing capacity calculation formula was proposed. Specimens showed higher fl exural strength than the nominal fl exural capacity, indicating that the proposed formula of nominal fl exural strength can eff ectively evaluate the strength of strengthening structures. A fi nite element model was established in ABAQUS software to verify the feasibility of nonlinear fi nite element method analysis on CSP strengthening structures and the parameter analysis was carried out. The simulation results showed that the reinforcement ratio had a great infl uence on the bearing capacity of the strengthening structure, and the bolt spacing was second. the compressive strength of concrete was not a signifi cant improvement eff ect of the bearing capacity of concrete-encased corrugated stiff ener structure, and the strength of concrete can be negligible. The optimization suggestions were proposed for the strengthening structure concerning other factors such as bolt spacing and strengthening ratio.

Analysis on Complexity and Evolution of E-Commerce Ecosystem

Honglu Liu,Zhihong Tian,Xiaolan Guan 보안공학연구지원센터(IJUNESST) 2013 International Journal of u- and e- Service, Scienc Vol.6 No.6