• Title/Summary/Keyword: Haiyan

Search Result 70, Processing Time 0.026 seconds

The Analysis of Climate Change in Haiyan County

  • Yu, Wenzheng;Zhang, Hanxiaoya;Chen, Tianliang;Liu, Jing;Shen, Yanbo
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.14 no.10
    • /
    • pp.3941-3954
    • /
    • 2020
  • In this paper, the climate change in Haiyan County in recent decades was analyzed in detail with the methods of moving average, Mann-Kendall non-parametric mutation test and wavelet analysis. According to the variation trend of meteorological factors such as temperature, relative humidity, wind speed, pan evaporation and precipitation in recent decades, the climate of Haiyan County has a tendency of drought, which is becoming more and more serious. From the results of the analysis, the sunshine hours and the air temperature in Haiyan County have an obvious upward trend. The average surface temperature has increased by 2.75 ℃ from 1976, and its largest increase occurred in the late 1970s and 1980s. At this stage, the average surface temperature increased by 1.37 ℃. The relative humidity has a decreasing trend that has decreased by 2.75%. From 1976 to the present, there are two quasi-3a cycles and one quasi-6a cycle. The precipitation and evaporation showed the opposite change trend, in which the trend of precipitation fluctuated upward, while the trend of evaporation showed a fluctuating downward tendency, which led to the serious loss of water in the feeding area. The wind direction in Haiyan County are mainly from west to east, and its wind speed has a trend of slight increase.

Evaluation of the Intensity Predictability of the Numerical Models for Typhoons in 2013 (2013년 태풍에 대한 수치모델들의 강도 예측성 평가)

  • Kim, Ji-Seon;Lee, Woojeong;Kang, KiRyong;Byun, Kun-Young;Kim, Jiyoung;Yun, Won-Tae
    • Atmosphere
    • /
    • v.24 no.3
    • /
    • pp.419-432
    • /
    • 2014
  • An assessment of typhoon intensity predictability of numerical models was conducted to develop the typhoon intensity forecast guidance comparing with the RSMC-Tokyo best track data. Root mean square error, box plot analysis and time series of wind speed comparison were performed to evaluate the each model error level. One of noticeable fact is that all models have a trend of error increase as typhoon becomes stronger and the Global Forecast System showed the best performance among the models. In the detailed analysis in two typhoon cases [Danas (1324) and Haiyan (1330)], GFS showed good performance in maximum wind speed and intensity trend in the best track, however it could not simulate well the rapid intensity increasing period. On the other hand, ECMWF and Hurricane-WRF overestimated the typhoon intensity but simulated track trend well.

Regional Realtime Ocean Tide and Storm-surge Simulation for the South China Sea (남중국해 지역 실시간 해양 조석 및 폭풍해일 시뮬레이션)

  • Kim, Kyeong Ok;Choi, Byung Ho;Lee, Han Soo;Yuk, Jin-Hee
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.30 no.2
    • /
    • pp.69-83
    • /
    • 2018
  • The South China Sea (SCS) is a typical marginal sea characterized with the deep basin, shelf break, shallow shelf, many straits, and complex bathymetry. This study investigated the tidal characteristics and propagation, and reproduced typhoon-induced storm surge in this region using the regional real-time tide-surge model, which was based on the unstructured grid, resolving in detail the region of interest and forced by tide at the open boundary and by wind and air pressure at the surface. Typhoon Haiyan, which occurred in 2013 and caused great damage in the Philippines, was chosen as a case study to simulate typhoon's impact. Amplitudes and phases of four major constituents were reproduced reasonably in general, and the tidal distributions of four constituents were similar to the previous studies. The modelled tide seemed to be within the acceptable levels, considering it was difficult to reproduce the tide in this region based on the previous studies. The free oscillation experiment results described well the feature of tide that the diurnal tide is prevailing in the SCS. The tidal residual current and total energy dissipation were discussed to understand the tidal and sedimentary environments. The storm-surge caused by typhoon Haiyan was reasonably simulated using this modeling system. This study established the regional real-time barotropic tide/water level prediction system for the South China Sea including the seas around the Philippines through the validation of the model and the understanding of tidal characteristics.

OSCILLATION OF NONLINEAR EQUATIONS ON TIME SCALES

  • Li, Qiaoluan;Liu, Zhiyong;Dong, Wenlei;Liang, Haiyan;Zhang, Zhenguo
    • Journal of applied mathematics & informatics
    • /
    • v.27 no.1_2
    • /
    • pp.327-334
    • /
    • 2009
  • By means of Riccati transformation techniques, we obtain some criteria which ensure that every solution of a nonlinear equation on time scales oscillates.

  • PDF

In-Situ Spectroelectrochemical Studies of Manganese(II) Oxidation

  • Zhang, Haiyan;Park, Su-Moon
    • Analytical Science and Technology
    • /
    • v.8 no.4
    • /
    • pp.569-574
    • /
    • 1995
  • In-situ spectroelectrochemical studies have been carried out on the oxidation of Mn(II) at platinum, gold, lead dioxide, and bismuth doped lead dioxide electrodes. The Mn(III), $MnO_2$, and/or ${MnO_4}^-$ species are produced depending on experimental conditions employed during electrolysis. Mn(III) is shown to be produced from a very early stage during the anodic potential scan and undergo disproportionation-conproportionation reactions depending on the relative concentration of each species near the electrode surface. An oxidation mechanism consistent with these observations is proposed.

  • PDF

Rapid Expression of Bm46 in Bombyx mori Cell Lines, Larvae and Pupae

  • Wang, Haiyan;Chen, Keping;Guo, Zhongjian;Yao, Qin;Wang, Qiang;Mu, Runhong
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.15 no.1
    • /
    • pp.35-38
    • /
    • 2007
  • In this study, ORF 46 of Bombyx mod nucleopolyhedrovirus(Bm46) fused with EGFP was expressed in Bombyx mod cell lines, larvae and pupae by BmNPV Bacmid system. Bm46 and EGFP were cloned into donor plasmid pFastBacHTb, which was transformed to competent DH10B cells containing helper and BmNPV bacmid by site-specific transposition. Recombinant bacmid was used to transfected BmN-4 cells to produce the recombinant baculovirus vBm-Bm46-EGFP. Recombination virus was injected into silkworm larvae and pupae. The expression of the fusion protein was monitored by examining green fluorescence using a fluorescent microscope. Intense fluorescence in cells and silkworm was observed at 4 days post-infection, indicating the Bm46-EGFP fusion gene was expressed successfully.

SOLVING A CLASS OF GENERALIZED SEMI-INFINITE PROGRAMMING VIA AUGMENTED LAGRANGIANS

  • Zhang, Haiyan;Liu, Fang;Wang, Changyu
    • Journal of applied mathematics & informatics
    • /
    • v.27 no.1_2
    • /
    • pp.365-374
    • /
    • 2009
  • Under certain conditions, we use augmented Lagrangians to transform a class of generalized semi-infinite min-max problems into common semi-infinite min-max problems, with the same set of local and global solutions. We give two conditions for the transformation. One is a necessary and sufficient condition, the other is a sufficient condition which can be verified easily in practice. From the transformation, we obtain a new first-order optimality condition for this class of generalized semi-infinite min-max problems.

  • PDF