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  • Author: Qian Wang x
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Open access

Wang Qian

Abstract

Croatia is a land endowed with rich and diversified natural and cultural tourist resources. Traveling around Croatia, I was stunned by its beauty. However, I noticed that there were few Chinese tourists in Croatia. How can we bring more Chinese tourists to Croatia? How can we make them happy and comfortable in Croatia? And, at the same time, how can we avoid polluting this tract of pure land? Based on first-hand research work, I make a SWOT analysis of the Chinese tourist source market of Croatia and put forward related countermeasures from the perspective of a native Chinese. The positioning of tourism in Croatia should be ingeniously packaged. I recommend developing diversified and specialized tourist products, various marketing and promotional activities, simple and flexible visa policies and regulations, and other related measures to further explore the Chinese tourist source market of Croatia.

Open access

Xian-Ling Wang and Ying-Qian Wang

Abstract

Hypopituitarism is a clinical syndrome caused by reduced production of adenohypophyseal hormones. The clinical manifestations of senile hypopituitarism are more complicated and a delay in diagnosis and treatment may lead to rapid development of pituitary crisis. Therefore, clinicians should be alerted to senile hypopituitarism. For patients with hyponatremia, hypoglycemia and unexplained coma, an evaluation of pituitary function should be performed. Hormone replacement therapy for patients with confirmed hypopituitarism should be standardized and unauthorized dose reduction or withdrawal is not allowed.

Open access

Qian Wang, Phillip Tobias, David Roberts and Zenobia Jacobs

A re-examination of a human femur found at the Blind River Site, East London, South Africa: Its age, morphology, and breakage pattern

Modern human femoral features might have appeared in the early Middle Stone Age (156 ka to 20 ka) in South Africa, as demonstrated by the recent re-examination of a human femur fossil found at the Blind River Site, East London in the 1930s, if new dating results hold. Two optically stimulated luminescence dates from the relocated original Blind River shallow marine/estuarine deposits that contained the femur gave almost identical ages of ~120 ka, corresponding to the early part of the Last Interglacial (Oxygen Isotope Stage 5). Overall, the slender headless femur is of modern human form. The distal epiphysis bears some typical squatting features, including a newly recognized squatting facet on the anterior wall of the intercondylar fossa. With the typical V-shaped and oblique fracture pattern left by the missing head, the Blind River femur was most likely modified through human activity. But this style is not a cultural trait found in recent South African people. Further study is needed to place this specimen in its due context in the course of human evolution.

Open access

Jian Zhang, Pengcheng Wang, Hongmei Tian, Haikun Jiang, Yan Wang, Ling Fang and Qian Zhang

Abstract

The cost of growing triploid watermelon seedlings has increased due to their low-efficiency grafting. The first priority in growing seedless watermelon seedlings is increasing the grafted-plant and seed-utilization rates. This study aimed to improve the grafted-plant rate by screening the most suitable substrate formulation, optimizing water moisture in the substrate, and evaluating the effect of different scions to improve seed-utilization rate. Five combinations of substrate (S1 to S5) and seven relative humidity levels (45%, 50%, 55%, 60%, 65%, 70%, and 75%) were used. Three types of scions (yellow bud, Ts-1; two cotyledons did not unfold, Ts-2; and first true leaf appeared, Ts-3) were tested. Results showed that the combination of S1 exhibited the best seed-utilization rate which was 71.6%. Moreover, the most suitable water moisture in the substrate ranged from 50% to 55%. The usage of the scion from Ts-3 significantly increased the grafting survival, grafted plant and seed-utilization rates by 13.7%, 10.1% and 22%, respectively, compared with the conventional method. Our study suggested that the best time to use the scion and the rootstock was during the seedling stage when the first true leaf unfolded. The proposed method decreased the production cost of seedlings and significantly improved the efficiency of grafting procedures. The results of this work are applicable to the technique of growing seedlings and can thus guide growers of high-quality grafted plants of triploid watermelon.

Open access

Xiu-zhi Meng, Zong-sheng Wang, Zeng-zhi Zhang and Feng-qian Wang

Abstract

Some small and medium-sized coal mines are mining beyond their mining boundary driven by profit. The illegal activities cause many mine disasters but effective supervision is very hard to achieve, especially for underground coal mining. Nowadays, artificial blasting operation is widely used in tunneling or mining in small and medium-sized coal mines. A method for monitoring the underground mining position by monitoring the blasting source position is firstly introduced in this paper. The blasting vibration waves are picked up by the detectors and dealt by the signal acquisition sub-station, and then sent to the principal computer. The blasting source is located by the principal computer and displayed in the mine’s electronic map. The blasting source position is located in 10 seconds after the first P wave reaching the detector, whose error is registered within 20 meters by field-proven method. Auto-monitoring of the underground mining position in real-time is solved better and management level is improved using this method.

Open access

Qian Wang, Xiaomei Yang, Xiao Yan and Kaiyu Qin

Abstract

Based on real-time multi-domain communication signal analysis architecture, a high-efficiency blind carrier frequency estimation algorithm using the power spectrum symmetry of the measured modulated signal is presented. The proposed algorithm, which utilizes the moving averaged power spectrum achieved by the realtime spectrum analysis, iteratively identifies the carrier frequency in according to the power difference between the upper sideband and lower sideband, which is defined and revised by the estimated carrier frequency in each iteration. When the power difference of the two sidebands converges to the preset threshold, the carrier frequency can be obtained. For the modulation analysis, the measured signal can be coarsely compensated by the estimated result, and the residual carrier frequency error is eliminated by a following carrier synchronization loop. Compared with previous works, owing to the moving averaged power spectrum normalization and the smart iterative step variation mechanism for the two sidebands definition, the carrier frequency estimation accuracy and speed can be significantly improved without increasing the computational effort. Experimental results are included to demonstrate the outstanding performance of the proposed algorithm.

Open access

Jinfeng Zhou, Lingjie Yu, Qian Ding and Rongwu Wang

Abstract

Fibers are raw materials used for manufacturing yarns and fabrics, and their properties are closelyrelated to the performances of their derivatives. It is indispensable to implement fiber identification in analyzing textile raw materials. In this paper, seven common fibers, including cotton, tencel, wool, cashmere, polyethylene terephthalate (PET), polylactic acid (PLA), and polypropylene (PP), were prepared . After analyzing the merits and demerits of the current methods used to identify fibers, near-infrared (NIR) spectroscopy was used owing to its significant superiorities, the foremost of which is it can capture the tiny information differences in chemical compositions and morphological features to display the characteristic spectral curve of each fiber . First, the fibers’ spectra were collected, and then, the relationships between the vibrations of characteristic chemical groups and the corresponding wavelengths were researched to organize a spectral information library that would be beneficial to achieve quick identification and classification. Finally, to achieve intelligent detection, pattern recognition approaches, including principal component analysis (PCA) (used to extract information of interest), soft independent modeling of class analogy (SIMCA), and linear discrimination analysis (LDA) (defined using two classifiers), assisted in accomplishing fiber identification. The experimental results - obtained by combining PCA and SIMCA - displayed that five of seven target fibers, namely, cotton, tencel, PP, PLA, and PET, were distributed with 100% recognition rate and 100% rejection rate, but wool and cashmere fibers yielded confusing results and led to relatively low recognition rate because of the high proportion of similarities between these two fibers. Therefore, the six spectral bands of interest unique to wool and cashmere fibers were selected, and the absorbance intensities were imported into the classifier LDA, where wool and cashmere were group-distributed in two different regions with 100% recognition rate. Consequently, the seven target fibers were accurately and quickly distinguished by the NIR method to guide the fiber identification of textile materials.

Open access

Da-yong Zhang, Song-song Yu, Yanlin Wang and Qian-jin Yue

Abstract

Bohai is a typical marginal oil field in an ice region, where most of the oil and gas platforms are economical. Sea ice is the main factor that affects the safety of oil and gas platforms in Bohai. Due to the complexity of the ice load and ice-induced vibrations, there are large security risks when developing Bohai oil and gas in the winter. It is difficult to ensure the safe production of oil and gas in winter using existing sea ice disaster warning technologies. Based on winter oil and gas production in the Bohai Sea’s Liaodong Bay, a set of suitable sea ice management systems is proposed in this paper. These systems integrate sea ice monitoring, risk assessment and risk prediction technologies. Based on the risk warning system, an ice management model of a Bohai ice platform has been put into practice, which ensures the safe production of the platform in winter.