Doppler-shift estimation of flat underwater channel using data-aided least-square approach

Weiqiang Pan,Ping Liu,Fangjiong Chen,Fei Ji,Jing Feng 대한조선학회 2015 International Journal of Naval Architecture and Oc Vol.7 No.2

In this paper we proposed a dada-aided Doppler estimation method for underwater acoustic communication. The training sequence is non-dedicate, hence it can be designed for Doppler estimation as well as channel equalization. We assume the channel has been equalized and consider only flat-fading channel. First, based on the training symbols the theoretical received sequence is composed. Next the least square principle is applied to build the objective function, which minimizes the error between the composed and the actual received signal. Then an iterative approach is applied to solve the least square problem. The proposed approach involves an outer loop and inner loop, which resolve the channel gain and Doppler coefficient, respectively. The theoretical performance bound, i.e. the Cramer-Rao Lower Bound (CRLB) of estimation is also derived. Computer simulations results show that the proposed algorithm achieves the CRLB in medium to high SNR cases.

Model-Checking Observational Transition Systems with Maude

Weiqiang Kong,Kazuhiro Ogata,Kokichi Futatsugi 대한전자공학회 2005 ITC-CSCC :International Technical Conference on Ci Vol.2005 No.1

Structural Deformation of Existing Horseshoe-Shaped Tunnels by Shield Overcrossing

Weiqiang Qi,Zhiyong Yang,Yusheng Jiang,Xiaokang Shao,Xing Yang,Qing He 대한토목학회 2021 KSCE Journal of Civil Engineering Vol.25 No.2

In urban areas, the construction of subway tunnels is faced with complex crossing problems. The interaction of tunnels with structural deformation has not been comprehensively studied, especially in the construction of new tunnels crossing above existing tunnels. To better predict the structural deformation of the existing tunnels caused by shield excavation, this study used FLAC3D finite difference software, field monitoring, and an analytical method. A numerical model was used to simulate the influence of the shield weight, grouting pressure, and the grout hardening process on the existing tunnel. The results show that the deformation of horseshoe-shaped tunnel structure can be divided into four stages and the corresponding control measures should be taken for each stage to prevent the structural damage. Moreover, the weight of the shield can restrain the existing tunnel from floating up, but it may cause the cracking of the existing tunnel structure without internal steel support. Based on the “two-stage analysis method”, the simplified analytical method solved the additional stress and the uplift deformation in the first stage and second stage, respectively. The proposed analytical method can rapidly estimate the maximum uplift deformation of the existing horseshoe-shaped tunnel with different bending stiffness values under shield excavation.

Evaluation of Three in-season Tests for Rapidly Detecting Resistance to Acetolactate Synthase Inhibitors in Schoenoplectus juncoides

WeiQiang Jia,Sug-Won Roh,Jae Eun Song,Aung Bo Bo,Kwang Min Cho,Kee Woong Park,Jeung Joo Lee 한국잡초학회·한국잔디학회 2021 Weed & Turfgrass Science Vol.10 No.1

Schoenoplectus juncoides is a noxious weed in paddy field of Korea. The excessive and unreasonable use of acetolactate synthase (ALS)-inhibiting herbicide caused the evolution of herbicide-resistant S. juncoides. As a part of the management of ALS-inhibiting herbicide resistance, early detection of the ALS-inhibiting herbicide resistance in S. juncoides is necessary. In this study, we evaluated three methods of rapidly detecting ALS-resistance in S. juncoides, including the cutting root test, cutting shoot test, and resistance in-season quick (RISQ) test. Three herbicide-resistant populations of S. juncoides (GR, 217R, and WR) and one susceptible population of S. juncoides (HS) collected from the Chungcheongnam-do and Jeollabuk-do of Korea served as experimental materials for the evaluation of three resistance test methods established by previous studies. In the three test methods, the GR and 217R were confirmed as resistant to flucetosulfuron and susceptible to penoxsulam. The WR was highly resistant to flucetosulfuron and penoxsulam. All the three resistance test methods have been successfully applied for identifying the ALS-inhibiting herbicide-resistant S. juncoides in-season. Especially, the result of cutting roots test demonstrated that the GR, 217R, and WR biotypes were highly resistant to flucetosulfuron with the R/S ratios of 34, 100, and 1852, respectively based on GR50. The WR biotype was highly resistant to penoxsulam with the R/S ratio of 912, whereas the GR and 217R biotypes were susceptible to penoxsulam. These in-season quick tests are likely to contribute to the use of effective herbicide in crops leading to decreased costs of labour and inputs in paddy field, and increased profits.

Preschool children medium-long distance stereoscopic vision testing

Weiqiang, Zhao,Xiaowang, Qiao,Singh, Sukh Mahendra Kyung Hee Oriental Medicine Research Center 2004 Oriental pharmacy and experimental medicine Vol.4 No.2

To test preschool children's medium- long distance stereoscopic vision normal average value, and intermittent strabismus children,s medium-long distance stereoscopic vision acuteness is the goal of this study. The software of random stereoscopic vision and graph, which is developed by Hu-Chong etc has been used, to test 414 cases normal preschool children and 19 cases intermittent exotropia childrens medium-long distance (1-5 m) stereoscopic vision (before operation and after operation). The normal average value of preschool children's medium-long distance stereoscopic vision was achieved. Intermittent exotropia children's stereoscopic vision acuteness was declined with the increase of distance. This method can provide reference as screening abnormal stereoscopic vision during scientific research and clinical work.

Weed Flora and Management Practices in Peach Orchard Fields in Korea

WeiQiang Jia,황기선,원옥재,이인용,이정란,노석원,박기웅 한국잔디학회 2017 Weed & Turfgrass Science Vol.6 No.2

This study was carried out two surveys in 2015 to monitor weed occurrence and determine the most troublesome weeds in peach orchards of Korea. The first survey identified 56 taxa belonging to 23 families including 27 annuals, 11 biennials, and 18 perennials. Based on importance values, Conyza canadensis (5.12%), Plantago asiatica (4.17%), and Trifolium repens (3.86%) were the dominant weeds in the first survey (from April to June). Seventeen exotic weeds were identified in the first survey, including Conyza canadensis, Trifolium repens, and Chenopodium ficifolium. The second survey (from September to October) identified 42 weeds belonging to 19 families including 23 annuals, 5 biennials, and 14 perennials. According to importance values, Digitaria ciliaris (8.00%) was the most dominant weed, followed by Echinochloa utilis (6.61%) and Rorippa palustris (6.48%). There were 12 exotic weeds, including Taraxacum officinale, Rumex crispus, and Trifolium repens. Additionally, according to Braun-Blanquet’s scale showed that the dominance value was level 1 (41.98% and 46.43%, respectively) in two surveys. Currently, 40% of the total surveyed peach orchards applied herbicides for weed control. These results could provide basic data to assist orchardists in selecting the most suitable weed management methods; thereby, reducing labor inputs and effectively lowering costs while improving fruit yields in peach orchards of Korea.

Differential Growth Response of Acetolactate Synthase Inhibitors-resistant Sagittaria trifolia Originated from Seeds and Tubers

WeiQiang Jia,Sug-Won Roh,Sung Hwan Choi,Jong Chan Won,Soo Yong Shim,Jung-Sung Chung,Le Thi Hien,Aung Bo Bo,Kee Woong Park,Jeung Joo Lee 한국잡초학회·한국잔디학회 2021 Weed & Turfgrass Science Vol.10 No.1

Continuous use of acetolactate synthase (ALS) inhibitors has led to the selection of herbicide-resistant Sagittaria trifolia in paddy fields. Herbicide-resistant (R) S. trifolia was first reported in 2011 in Korea. The objective of this study was to investigate the level and mechanism of resistance and understand the fitness of R biotypes using R and susceptible (S) S. trifolia biotypes originated from seeds and tubers. Whole plant dose-response showed that the R biotypes originated from tubers were highly resistant to cyclosulfamuron and moderately resistant to penoxsulam and imazaquin, with R/S ratios of 250, 13 and 8, respectively. Compared to the S biotype, the R biotype originated from tuber had an amino acid substitution at the position of a Pro197-Leu residue of als gene, a well-known mutation site that could confer resistance to sulfonylurea, triazolopyrimidine, and imidazolinone herbicides. Additionally, the germination rate and growth of the S biotypes originated from seeds were lower than those of the R biotypes. The growth of the S biotypes originated from tubers was more vigorous than that of the R biotypes. Once the seed of R biotypes move to uninfected paddy fields, the germination rate of R biotypes is probably more than that of existing S biotypes. If ALS inhibitors are applied into paddy fields, R biotypes can survive and even produce tubers that can continually propagate and probably become dominant in the population in uninfected paddy fields. Thus, increasing the application rate of ALS inhibitors to kill R biotypes probably can enhance ALS-inhibitors’ selection-pressure.

A Remote Wireless Networked Sensing System for Monitoring Stress of Fruits during Transportation

Weiqiang YANG,Yali XI,Noriyoshi YAMAUCHI,Yoshitada MIYAZAKI,Noriko BABA,Hironobu IKEDA 제어로봇시스템학회 2006 제어로봇시스템학회 국제학술대회 논문집 Vol.2006 No.10

Weed Flora and Management Practices in Peach Orchard Fields in Korea

Jia, WeiQiang,Hwang, Ki Seon,Won, Ok Jae,Lee, In-Yong,Lee, Jeongran,Roh, Suk-Won,Park, Kee Woong The Korean Society of Weed ScienceThe Turfgrass So 2017 Weed & Turfgrass Science Vol.6 No.2

This study was carried out two surveys in 2015 to monitor weed occurrence and determine the most troublesome weeds in peach orchards of Korea. The first survey identified 56 taxa belonging to 23 families including 27 annuals, 11 biennials, and 18 perennials. Based on importance values, Conyza canadensis (5.12%), Plantago asiatica (4.17%), and Trifolium repens (3.86%) were the dominant weeds in the first survey (from April to June). Seventeen exotic weeds were identified in the first survey, including Conyza canadensis, Trifolium repens, and Chenopodium ficifolium. The second survey (from September to October) identified 42 weeds belonging to 19 families including 23 annuals, 5 biennials, and 14 perennials. According to importance values, Digitaria ciliaris (8.00%) was the most dominant weed, followed by Echinochloa utilis (6.61%) and Rorippa palustris (6.48%). There were 12 exotic weeds, including Taraxacum officinale, Rumex crispus, and Trifolium repens. Additionally, according to Braun-Blanquet's scale showed that the dominance value was level 1 (41.98% and 46.43%, respectively) in two surveys. Currently, 40% of the total surveyed peach orchards applied herbicides for weed control. These results could provide basic data to assist orchardists in selecting the most suitable weed management methods; thereby, reducing labor inputs and effectively lowering costs while improving fruit yields in peach orchards of Korea.

Potassium isotope fractionation between K-salts and saturated aqueous solutions at room temperature: Laboratory experiments and theoretical calculations

Li, Weiqiang,Kwon, Kideok D.,Li, Shilei,Beard, Brian L. Pergamon Press 2017 Geochimica et cosmochimica acta Vol.214 No.-

<P><B>Abstract</B></P> <P>Improvements in mass spectrometry have made it possible to identify naturally occurring K isotope (<SUP>39</SUP>K/<SUP>41</SUP>K) variability in terrestrial samples that can be used in a variety of geological and biological applications that involve cycling of K such as clay or evaporite formation. However, our ability to interpret K isotope variability is limited by a poor understanding of how K isotopes are fractionated at low temperatures. In this study, we conducted recrystallization experiments of eight K-salts in order to measure the K isotope fractionation factor between the salt and the saturated K solution (Δ<SUP>41</SUP>K<SUB>min-sol</SUB>). Measured Δ<SUP>41</SUP>K<SUB>min-sol</SUB> are +0.50‰ for K<SUB>2</SUB>CO<SUB>3</SUB>·1.5H<SUB>2</SUB>O, +0.32‰ for K<SUB>2</SUB>SO<SUB>4</SUB>, +0.23‰ for KHCO<SUB>3</SUB>, +0.06‰ for K<SUB>2</SUB>C<SUB>2</SUB>O<SUB>4</SUB>·H<SUB>2</SUB>O, +0.02‰ for KCl, −0.03‰ for K<SUB>2</SUB>CrO<SUB>4</SUB>, −0.15‰ for KBr, and −0.52‰ for KI. Overall the Δ<SUP>41</SUP>K<SUB>min-sol</SUB> decreases with increasing <I>r</I> for K in crystals, where <I>r</I> is the average distance between a K atom and its neighboring atoms of negative charge. Salts with monovalent anions and salts with divalent anion complexes define different linear trends with distinct slopes on a plot of Δ<SUP>41</SUP>K<SUB>min-sol</SUB> - <I>r</I>. We applied <I>ab initio</I> lattice dynamics and empirical crystal-chemistry models to calculation of K isotope fractionation factors between K salts; both methods showed that the calculated inter-mineral K isotope fractionation factors (Δ<SUP>41</SUP>K<SUB>min-KCl</SUB>) are highly consistent with experimentally derived Δ<SUP>41</SUP>K<SUB>min-KCl</SUB> under the assumption of consistent β factors for different saturated K solutions. Formulations for the crystal-chemistry model further indicate that both anion charge and bond length <I>r</I> are the principle controlling factors for K isotope fractionation, and the K isotope fractionation factors correlate with <I>r</I> following a 1/<I>r</I> <SUP>3</SUP> relationship. Our experiment and theoretical study confirms the existence of significant equilibrium K isotope fractionation at ambient conditions, and the K isotope fractionation factors for halides and sulfate obtained in this study provide a basis for future K isotope studies on evaporites.</P>