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ObjectiveThis study aimed to investigate the effects of stellate ganglion block (SGB) through different approaches under guidance of ultrasound.MethodsA total of 130 patients undergoing SGB in our hospital between February 2019 and February 2020 were enrolled as the research subjects. According to the random number table method, these subjects were divided into two groups: a modified 6th cervical vertebra (C6) group (n = 65) and a 7th cervical vertebra (C7) group (n = 65). Under the guidance of ultrasound, the subjects in the modified C6 group were punctured at the level of the C6 transverse process, and the subjects in the C7 group were punctured at the level of the C7 transverse process. The operation duration, number of puncture angle adjustments, block effects, and adverse reactions for SGB were compared between the two groups.ResultsThe modified C6 group showed shorter SGB operation duration and a lower number of puncture angle adjustments than the C7 group, and the differences were statistically significant (P < 0.05). Horner Syndrome occurred in both groups after SGB. The incidence of adverse reactions in the modified C6 group was 4.62%, comprising 1 case of hoarseness and 2 cases of slowed pulse, while that in the C7 group was 6.15%, with 1 case of hoarseness and 3 cases of slowed pulse; the difference between the two groups was not statistically significant (P > 0.05).ConclusionThe operation duration for modified SGB guided by ultrasound puncturing at the C6 transverse process is shorter and requires fewer puncture angle adjustments than puncturing at the C7 transverse process; however, there is no significant difference between the incidence of adverse reactions or the blocking effects of the two methods.

A flume experiment is carried out to explore regular waves shoaling and breaking in surf zone. The topography is two-slope model, which is composed of a steep slope 1:5 and a gentle slope 1:40. The incidence waves have heights of 0.05, 0.06, 0.07, 0.08, 0.09 and 0.10 m, and periods of 1.0 sec. In order to describe the wave propagation in surf zone, wave height is collected by wave gauges and wave breaking is recorded by high-speed camera. The results show that, when incidence height is increased, the breaking height increases, while the location of breaking point moves forward. When the incidence height is larger enough, the trend slow down. Besides, secondary breakup is observed in case 0.08, 0.09 and 0.10m. The transient period from primary breakup to secondary breakup is a very important phase. Computing and forecasting methods of surf with complicated topography need further study.

Wave breaking is the most complex and intensified physical process in coastal zone. And as the maximum in this area, the breaking wave height has a major impact on ocean engineering and ship sailing. In this paper, the present calculation methods for breaking height are concluded and divided into two categories: one is directly computing models using deep wave elements; the other is indirectly calculation models based on the surf wave calculation model and the criterion of breaking.

When ship navigates at sea, collision avoidance of ship’s speed alteration is frequently adopted by officer on watch in order to prevent from forming collision situation with target ship(s). Bacterial foraging algorithm (BFA) that imitates the social foraging behavior of Escherichia coli is an optimal search method suitable for complex problems. This research adopts the bacterial foraging algorithm to find the speed alteration collision avoidance strategy from an economical viewpoint, combining the international regulations for preventing collisions at sea (COLREGS) and the safety domain of ship. An optimal time of changing speed, amplitude of speed alteration and navigation restoration time will also be provided. The effectiveness of the algorithm has been verified by simulation. The study offers new thinking and a practical method for collision avoidance decision.

Using HF-Doppler detector we have been observed ionosphere disturbance continuously for about 20 years. Firstly, We gave a theoretic explanation to normal frequency-shift records, then using two typical cases we pointed out that in china there exist F2 layer infrasonic disturbance which due to severe weather. Through analyzing their spectrums, we found three remarkable peaks. And comparing with foreign researchers, we indicated that infrasonic disturbances possess local features. Finally, we concluded local features of infrasonic disturbances occurring in our area.

In order to design a double buoys mooring system in the estuary of Yalu River for loading work of 40,000 tons of bulk cargo ship, the article mainly based on the practicality of the meteorological condition of this sea area and the data of the vessel as well as the national criterion, do some calculations of wind force, current force, wave force as well as the total force on the ship, with the calculation result to make a designation of double mooring buoy system, decide the size of the mooring buoy, the size and length of the chain, the size and the depth of the Deadman. The construction according to the designation has a good effect; the method of calculation and the designation are proved useful.

In order to evaluate the ship traffic safety about the large water area, the system of maritime macroscopic traffic safety was developed, which can give the simulation result under the setting conditions, using the electronic chart display and information system conform to S57 and S52. The simulation model of ship traffic flow is proposed, which play an important part in the system. The outcome can be provided according to the assessment method of maritime safety, and displayed on the ECDIS. With the clicking on the icons by the mouse button, the information about the simulation can be offered.

Over the last decade, neural networks have found application for solving a wide range of areas from business, commerce, data mining and service systems. Hence, this paper constructs a new model based extension theory and neural network to forecast the ship transportation. The new neural network is a combination of extension theory and neural network. It uses an extension distance to measure the similarity between data and cluster center, and seek out the useless data, then to use neural network to forecast. When presenting a test example of prediction of ship transportation, the results verifies the effectiveness and applicability of the novel extension neural network. Compared with other forecasting techniques, especially other various neural networks, the extension neural network permits an adaptive process for significant and new information, and gives simpler structure, shorter learning times and higher accuracy.

In the simulation of underwater acoustic propagation, sound speed is usually characterized by the vertical distribution of the sound speed profile (SSP), but it ignores lateral variation. This paper carried out simulation on constant SSP, negative and positive gradient profile, and real sound speed profiles (SSPs), concerning a Gulf Stream scenario, and by using Bellhop model. The characteristics of underwater acoustic propagation in the horizontal direction are discussed. The results show that the changes of sound velocity in the horizontal direction have a certain effect on underwater sound propagation. With the horizontal sound speed increasing for the steady SSPs, the number of eigenrays increase, and the transmission loss and the arrival times decrease. Conversely, the number of eigenrays decrease, and the transmission loss and the arrival times increase. With the horizontal changes of the unsteady SSPs, underwater acoustic propagation is basically followed by this law, but the transmission loss may change suddenly in some cases. It has a certain reference value for underwater acoustic modeling. Further work will be discussed and analyzed in the future.

This paper uses the information on the Xijiang floating production storage and offloading mooring system coupled with dynamic analysis of the system to generate scenarios for the most likely causes of the damage to the wires and if this is likely to result in further progressive damage of the mooring system. The modeling reflects the fundamentals of the Xijiang FPSO mooring system and can be used to further investigate potential causes for the mooring leg damage. The mooring dynamic analysis has been used to investigate the indicative behavior of the mooring lines under various conditions when BTM connected. The model has been used to investigate the tensions, bending moments and bending radiuses close to the lower socket. However the models have been checked to determine that they produce results which are of the correct order for the mooring system.

A dynamic model for estimating position of ship towed array during U-turn manoeuvre is introduced and developed. Based on this model, the influences of the parameters such as time step and segment length on the numerical simulation are analysed. The results indicate that decreasing the time step has little effect on the simulation accuracy but will increase the computational time. The selection of segment length has a great influence on the estimation of ship towed array position during U-turn manoeuvre. Reducing the segment length somewhat increases the computational complexity and significantly improves simulation precision.

An excellent strain (designated as T-3) which produces bio-flocculants was isolated from soil samples, and identified as Klebsiella sp. species based on the analysis of morphology, physiology and biochemistry and 16S rDNA sequences measurement. The effects of culture conditions such as pH values, temperature, carbon sources and nitrogen sources on bio-flocculants production by T-3 strain were studied. The experiment results show that T-3 strain has better adaptability to carbon sources and nitrogen sources, and higher capacity of bio-flocculants was obtained when the initial pH value of culture and temperature were 9 and 25 degrees C respectively. Based on the colorimetric reactions of proteins and polysaccharide substance, ultraviolet scanning analysis and Fourier Transform Infrared Spectroscopy analysis, it is found that the bio-flocculants produced by T-3 strain contains -OH and -COO(-) groups and belongs to anionic type flocculant. Moreover, the main component is polysaccharides. The treatment of oily cold-rolling wastewater by the bio-flocculant was investigated and the better result was obtained. When the dosages of CaCl2, bio-flocculants and poly aluminium chloride were 4 g x L(-1), 10% (volume fraction) and 1 g x L(-1) respectively, and the pH value was 7.0, the oil concentration, COD and turbidity were decreased to 10 mg x L(-1), 218.4 mg x L(-1) and 1.36 from 4 819 mg x L(-1), 28 456.8 mg x L(-1) and 3 950 with the removal efficiencies of 99.79%, 92.32% and 99.97% respectively. The interaction between flocculant and oily droplets is achieved by the interaction of Van der Waals force, hydrogen bond and the bridged coordination of Ca2+, in which the bridged coordination of Ca2+ is the dominant.