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1

Simulation on vessel intelligent collision avoidance based on artificial fish swarm algorithm

100%
Li W., Ma W.
Polish Maritime Research
|
2016
|
tom 23
|
nr Special Issue S1
TAs the rapid development of the ship equipments and navigation technology, vessel intelligent collision avoidance theory was researched world widely. Meantime, more and more ship intelligent collision avoidance products are put into use. It not only makes the ship much safer, but also lighten the officers work intensity and improve the ship’s economy. The paper based on the International Regulation for Preventing Collision at sea and ship domain theories, with the ship proceeding distance when collision avoidance as the objective function, through the artificial fish swarm algorithm to optimize the collision avoidance path, and finally simulates overtaking situation, crossing situation and head-on situation three classic meeting situation of ships on the sea by VC++ computer language. Calculation and simulation results are basically consistent with the actual situation which certifies that its validity
2

Test research on the resistance performance of high-speed trimaran planing hull

81%
Ma W., Sun H., Zou J., Yang H.
Polish Maritime Research
|
2013
|
tom 20
|
nr 4
In order to identify high-speed navigation ability of trimaran planing hull, as well as investigate the characteristics of its resistance and hull form, ship model tests were conducted to measure resistance, trim and heaving under different displacements and gravity centre locations. The test results were then used to study the influence of spray strips on resistance and sea-keeping qualities. Moreover, different planing surfaces were compared in the model tests which helped to look into influence of steps on hull resistance and its moving position. Also, the resistance features of monohull and trimaran planing hulls, both with and without steps, were compared to each other. From the tests it can be concluded that: the two auxiliary side hulls increase aerodynamic lift at high-speed motion, which improves the hydrodynamic performance; the trimaran planing hull has also excellent longitudinal stability and low wave-making action; when Fr∇ > 8, its motion is still stable and two distinct resistance peaks and two changes of sailing state (the second change is smaller) appear; spray strips are favourable for sea-keeping qualities at high speed. The change trends before the second resistance peak as to the resistance and sailing behaviour of trimaran planing hull without steps are the same as for monohull planing hull without steps. but when steps in both hulls exist the change trends are different; more specifically: trimaran planing hull with steps has only one resistance peak and its resistance increases along with its speed increasing, and the resistance is improved at the increasing speed as the number of steps increases
3

Effects of GnRH agonist on reproductive functions of female rabbits

81%
Wi S., Gong Z., Ma W., Wei M.
Animal Science Papers and Reports
|
2012
|
tom 30
|
nr 1
The physiological efficiency and mechanisms of action were studied of gonadotropin releasing hormone analogue (GnRH-A) on the reproductive functions of rabbits. Twenty-four female rabbits (Oryctolagus cuniculus) were randomly divided into four groups. Group EG-1, EG-2 and EG-3 were subcutaneously injected with 1.0 mL GnRH-A antigen at 100 μg/mL, 100 μg/mL and 50 μg/mL. EG-2 and EG-3 were re-injected on day 20. CG was a control group. Ovary and uterus samples in each animal were collected aseptically on day 70. The tissue slices were observed under optical and electron microscopy. Serum FSH and LH concentrations were detected using ELISA.GnRHR, FSH-β and LH-β genes were assayed with real time PCR. OCT, PFV, PFT, EET and UWT were measured with Motic system. The results showed that FSH and LH concentrations in EG-2 and EG-3 reached the peak on day 40. EG-2 was higher than EG-1 and CG (P<0.01) and EG-3 (P<0.05). GnRHR in EG-3 was higher than that in EG-1 and EG-2 (P<0.05). FSH-β in EG-1 and EG-3 were lower than that in EG-2. Meanwhile, LH-β in EG-3 was less than in EG-1 and EG-2.The homologies of GnRHR, FSH-β and LH-β sequences were 98%, 100% and 94% respectively,with those reported in National Center of Biotechnology Information (NCBI). OCT in EG-1 and EG-3 thickened with a maxium in EG-3. PFV, PFT, EET and UWT in EGs were larger than that in CG (P<0.05) Primary and secondary follicles in EGs increased and growed quickly. Nucleolus and mitochondria in EGs were enlarged. Zona pellucida and microvillus of the oocytes broadened and lengthened. In conclusion, GnRH-A could increase synthesis and secretion of FSH and LH, and promote the development of ovary and follicles.
4

A new anti-counterfeiting method: fluorescent labeling by safranine T in tobacco seed

71%
Guan Y., Hu J., Li Y., Ma W., Zheng Y.
Acta Physiologiae Plantarum
|
2011
|
tom 33
|
nr 4
Counterfeit seeds cause a large loss in seed industry and crop production. Present study was undertaken to find a new anti-counterfeiting technology by labeling seeds with a fluorescent compound, safranine T (ST). Response surface analysis (RSA) experiment with two factors (ST concentration and seed soaking time) of 14 combinations was performed to investigate the ST effects on seed vigor and fluorescence showing in seedlings of two tobacco varieties, MS Yunyan 85 and Honghua Dajinyuan. After soaking in ST solutions, tobacco seeds were germinated for 16 days, then the germination index (GI), vigor index (VI), length of roots and shoots were determined. The optimum combinations of ST concentration and soaking time on GI, VI and length of shoots and roots were 0.57–0.69 mg/ml and 6.77–9.34 h for MS Yunyan 85 and 0.51–0.80 mg/ml and 5.81–7.39 h for Honghua Dajinyuan, respectively. Meanwhile, tobacco seedlings, treated with ST solutions from 0.3 to 1.5 mg/ml showed obviously fluorescence under illumination of green light. It suggests that soaking tobacco seeds in safranine T solution of suitable concentration can be used as a labeling technique for anti-counterfeiting in tobacco seeds.
5

Test studies of the resistance and seakeeping performance of a trimaran planing hull

71%
Ma W., Sun H., Sun H., Zou J., Zhuang J.
Polish Maritime Research
|
2015
|
tom 22
|
nr 1
Towing tank tests in calm water were performed on a trimaran planing hull to verify its navigational properties with different displacements and centres of gravity, as well as to assess the effects of air jets and bilge keels on the hull’s planing capabilities, and to increase the longitudinal stability of the hull. Hydrostatic roll tests, zero speed tests, and sea trials in the presence of regular waves were conducted to investigate the hull’s seakeeping ability. The test results indicate that the influence of the location of the centre of gravity on the hull resistance is similar to that of a normal trimaran planing hull; namely, moving the centre of gravity backward will reduce the resistance but lower the stability. Bilge keels improve the longitudinal stability but slightly affect the resistance, and the presence of air jets in the hull’s channels decreases the trim angle and increases heaving but has little effect on the resistance. Frequent small-angle rolling occurs in waves. The heaving and pitching motions peak at the encounter frequency of , and the peaks increase with velocity and move towards greater encounter frequencies. When the encounter frequency exceeds, the hull motion decreases, which leads to changes in the navigation speed and frequency
6

Numerical simulations of linearly stratified flow past submerged bodies

71%
Ma W., Li Y., Ding Y., Hu K., Lan L.
Polish Maritime Research
|
2018
|
tom 25
|
nr Special Issue S3
In this study, a methodology was presented to predict density stratified flows in the near-field of submerged bodies. The energy equation in temperature form was solved coupled with momentum and mass conservation equations. Linear stratification was achieved by the definition of the density as a function of temperature. At first, verifications were performed for the stratified flows passing a submerged horizontal circular cylinder, showing excellent agreement with available experimental data. The ability of the method to cope with variable density was demonstrated. Different turbulence models were used for different Re numbers and flow states. Based on the numerical methods proposed in this paper, the stratified flow was studied for the real scale benchmark DAPRA Suboff submarine. The approach used the VOF method for tracing the free surface. Turbulence was implemented with a k − ω based Detached Eddy Simulation (DES) approach. The effects of submarine speed, depth and density gradient on the free surface wave pattern were quantitatively analyzed. It was shown that, with the increasing of the speed of the submarine, the wavelength and wave height of the free surface wave were gradually increasing. The wave height of the free surface wave was gradually reduced as the submarine’s depth increased. Relative to the speed and submarine depth, the changes of the gradient density gradient have negligible effects on the free surface wave field
7

Increased activity of only an individual non-regulated enzyme fructose-1,6-bisphosphate aldolase in Anabaena sp. strain PCC 7120 stimulates photosynthetic yield

71%
Ma W., Wei L., Long Z., Chen L., Wang Q.
Acta Physiologiae Plantarum
|
2008
|
tom 30
|
nr 6
The goal of this study was to investigate the contribution of increased activity of individual nonregulated enzymes in the Calvin cycle to improve photosynthetic yield. Two non-regulated enzymes, rice fructose-1,6-bisphosphate aldolase (FBA) and spinach triosephosphate isomerase (TPI), were individually cloned and overexpressed in the cyanobacterium Anabaena sp. strain PCC 7120 cells. The enzyme activity and the photosynthetic yield, as reflected by the cell growth rate, photosynthetic oxygen evolution and dry cellular weight, were measured and compared between the wild-type and transgenic cells harboring either FBA or TPI. Though the activity of these two individual non-regulated enzymes was similarly increased in the corresponding transgenic cells, the contributions of each enzyme on the amount of ribulose- 1,5-bisphosphate carboxylase/oxygenase (Rubisco), reflected by the levels of Rubisco large subunit, and the photosynthetic yield were different. Transgenic cells, carrying FBA, showed an evident increase in Rubisco amount and photosynthetic yield, while there was no increase in cells harboring TPI. This indicates that the contributions of non-regulated enzymes in the Calvin cycle on photosynthetic yield differed and firstly reveals that increased activity of only a single non-regulated enzyme in transgenic cells markedly improves the photosynthetic yield via stimulating the amount of Rubisco and consequently accelerating the ribulose-1,5-bisphosphate (RuBP) regeneration rate.
8

Atmospheric dry deposition to natural water of wetland in suburban Beijing

61%
Wang Y., Mo L., Cong L., Zhai J., Ma W., Zhang Z.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 2
9

LncRNA H19 promotes the differentiation of bovine skeletal muscle satellite cells by suppressing Sirt1/FoxO1

61%
Xu X., Ji S., Li W., Yi B., Li H., Zhang H., Ma W.
Cellular and Molecular Biology Letters
|
2017
|
tom 22
10

Motion prediction of catamaran with a semi-submersible bow in wave

61%
Sun H., Jing F., Jiang Y., Zou J., Zhuang J., Ma W.
Polish Maritime Research
|
2016
|
tom 23
|
nr 1
Compared with standard vessels, a slender catamaran with a semi-submerged bow (SSB) demonstrates superior seakeeping performance. To predict the motion of an SSB catamaran, computational fluid dynamics methods are adopted in this study and results are validated through small-scale model tests. The pitch, heave, and vertical acceleration are calculated at various wavelengths and speeds. Based on the overset grid and motion region methods, this study obtains the motion responses of an SSB catamaran in regular head waves. The results of the numerical studies are validated with the experimental data and show that the overset grid method is more accurate in predicting the motion of an SSB catamaran; the errors can be controlled within 20%. The movement data in regular waves shows that at a constant speed, the motion response initially increases and then decreases with increasing wavelength. This motion response peak is due to the encountering frequency being close to the natural frequency. Under identical sea conditions, the motion response increases with the increasing Froude number. The motion prediction results, that derive from a shortterm irregular sea state, show that there is an optimal speed range that can effectively reduce the amplitude of motion
11

Dynamic response analysis among environmental regulation, technological progress and water resource consumption in China’s textile industry

61%
Li Y., Wang Y., Ding L., Ke L., Ma W., Yang Y.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 4
12

The role of Exo70 in vascular smooth muscle cell migration

61%
Ma W., Wang Y., Yao H., Xu Z., An L., Yin M.
Cellular and Molecular Biology Letters
|
2016
|
tom 21
13

Ecological heavy metals risk of saline lake sediments in Northwestern China

51%
Li D., Jiang J., Yan C., Zhang M., Xiang Y., Ma W., Jia H., Zhao X.
Polish Journal of Environmental Studies
|
2020
|
tom 29
|
nr 4
14

Effects of Abietinella abietina extracts on the germination and seedling emergence of Picea crassifolia: results of greenhouse experiments

42%
Wang Q., Zhao C., Gao Y., Gao C., Qiao Y., Xie H., Wang W., Yuan L., Liu J., Ma W., Li W.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 3
Moss cushion plays an important role in recruitment of vascular plants. In this study, we examined the effects of water soluble extracts (WSE) of Abietinella abietina on germination of Qinghai spruce (Picea crassifolia) and the effects of moss substrates (A. abietina) on seedling emergence of P. crassifolia in two greenhouse experiments. We found that the WSE of moss affected germination of P. crassifolia in two ways: (1) the WSE reducing the risk of fungal infection to the seeds, improve the germination rate; and (2) the WSE affects germination by its concentration, that is, low concentrations of WSE (i.e., 0.5 mg ml⁻¹ and 5 mg ml⁻¹) stimulate, while high concentrations (i.e., 50 mg ml⁻¹) inhibit it. In seedling emergence experiments, we detected that the moss substrates (both thick and thin mosses) facilitate the emergence of P. crassifolia in dry and intermediate moisture conditions, but inhibit it in moist conditions. In bare soil, the P. crassifolia emergence was also controlled by moisture conditions; the highest (60%) and the lowest (35%) emergence occurred in the moist conditions and dry conditions, respectively. We also found that P. crassifolia seedlings were thinner and taller, but their number higher in moss cushion than in bare soil. Thus we conclude that there is nurse effect of A. abietina cushion on recruitment of P. crassifolia in both dry and intermediate moisture conditions.
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