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Botanicals, selective insecticides, and predators to control Diaphorina citri （Hemiptera： Liviidae） in citrus orchards

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Insect Science 2014年第6期21卷 717-726页

作者： Azhar A. khan Muhammad Afzal Jawwad A. Qureshi Arif M. khan Abubakar M. Raza Department of Agricultural Entomology University of Sargodha Sargodha Pakistan Department of Entomology & Nematology Southwest Florida Research and Education Center Institute of Food and Agricultural Sciences University of Florida Immokalee Florida USA Department of Biotechnology University of Sargodha Sargodha Pakistan

The Asian citrus psyllid （ACP） Diaphorina citri Kuwayama vectors pathogens that cause huanglongbing （HLB） or citrus greening devastating and economically im- portant disease present in most citrus growing regions. Young citrus shoots are required for psyllid reproduction and development. During winter citrus trees produce little or no new growth. Overwintering adults reproduce in spring on newly emerging shoots also attractive to other pests and beneficial insects. Botanicals and relatively selective insecti- cides could help to conserve beneficial insects and reduce pest resistance to insecticides. Sprays of Azadirachtin （Neem）, Tropane （Datura）, Spirotetramat, Spinetoram, and broad- spectrum imidacloprid were evaluated to control ACP in spring and summer on 10-year-old ＂Kinow＂ Citrus reticulata Blanco trees producing new growth. Psyllid populations were high averaging 5-9 nymphs or adults per sample before treatment application. Nymphs or adults were significantly reduced to 0.5-1.5 per sample in all treatments for 3 weeks, aver- age 61%-83% reduction. No significant reduction in ladybeetles Adalia bipunctata, Ane- glei scardoni, Cheilomenes sexmaculata, and Coccinella septempunctata was observed. Syrphids, spiders and green lacewings were reduced in treated trees except with Tropane. Studies are warranted to assess impact of these predators on ACP and interaction with insecticides. Observed reduction in ACP populations may not be enough considering its reproductive potential and role in the spread of HLB. Follow-up sprays may be required to achieve additional suppression using rotations of different insecticides.

关键词： Asian citrus psyllid biopesticides Coccinellids huanglongbing predators

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Increasing Distance Increasing Bits Substitution (IDIBS) Algorithm for implementation of VTVB Steganography

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Computer Modeling in Engineering & Sciences 2018年第10期117卷 1-16页

作者： Sahib khan Arslan Arif Syed Tahir Hussain Rizvi Nasir Ahmad Department of Electronics and Telecommunications Politecnico di Torino10129 TorinoItaly DAUIN Politecnico di Torino10129 TorinoItaly Department of Electronic and Electrical Engineering Loughborough UniversityUnited Kingdom

Cryptography and steganography are two important and related fields of information ***,steganography is slightly different in the sense that it hides the existence of secret information from unauthorized *** is one of the most appealing research domains,have applications like copyright protection,data integrity protection and manipulation *** steganography techniques have been proposed in ***,in this work a new information hiding algorithm is *** proposed technique de-correlates frequency components of cover image using discrete cosine transform and uses the least significant bits of frequency components for hiding secret *** tech-nique hides variable number of bits of secret message in different frequency ***,it hides different amount of secret information in different regions of cover im-age and results in enhancement of *** algorithm has the flexibility to change the hiding capacity and quality of final stego *** has been observed from experimental results that a hiding a capacity from 3%to 43%can be achieved with significantly good quality of 41 dB to 37 dB in term of peak signal to noise *** successful recovery of the hidden information need the pattern,called stego key,in which is used in hiding *** algorithm provides twofold security;hiding keeps the existence of hidden information secret and the large key size makes the retrieval of hidden information difficult for intruders.

关键词： VTVB steganography image processing information security data hiding

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Demonstrating Fuel Flexibility in Commercial Operation

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International Journal of Clean Coal and Energy 2012年第2期1卷 27-33页

作者： Fawad khan Francis Lau Synthesis Energy Systems Inc. Houston USA

Synthesis Energy Systems Inc. (SES) enables its customers to advance gasification projects through commercial scale feedstock testing at its commercial scale coal to syngas facility in Zhao Zhuang City (ZZ Plant), Shandong Province, China. These tests help customers affirm individual project economic viability and reduce technology risk. Included in these test campaigns have been one and two-week long continuous operations at varying loads and on widely-varying feedstock such as Chinese Inner Mongolian lignite, Chinese sub-bituminous high ash (and high friable) coal, and Aus- tralian Queensland high ash sub-bituminous coal. Through these campaigns, SES has progressed one project into the detailed engineering and construction phase and one project into the feasibility study phase. SES believes that the abi- lity to perform these commercial scale campaigns without interruption of operation is unique to SES. The ZZ Plant, which sells clean syngas to a neighboring methanol facility, has been in operation since early 2008 on a design coal of high ash middlings (washery wastes) from ROM bituminous coal (30% - 40% wt ash). SES has made significant im-provements to the design, operation, and efficiency of the ZZ Plant and U-GAS technology that is licensed from Gas Technology Institute (GTI). Included in these is the Fines Management System (FMS), which has demonstrated overall carbon conversion of greater than 98%. The ZZ Plant consistently demonstrates fuel flexibility and greater than 98% availability, 98% carbon conversion, and 80% cold gas efficiency.

关键词： Gasification U-GAS Fluid Bed Gasification Low Rank Coal Lignite Biomass

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Cost Effective Scheme for OLT in Next Generation Passive Optical Access Network Based on Noise Free Optical Multi Carrier

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China Communications 2016年第6期13卷 76-87页

作者： Rahat Ullah Bo Liu Qi Zhang Qinghua Tian Amjad Ali Yousaf khan Feng Tian M.Azam Zia Haseeb Ahmad Lijia Zhang Xiangjun Xin State Key Laboratory of Information Photonics and Optical Communications.Beijing University of Posts and Telecommunications No.10 Xitucheng RoadBeijingChina100876 School of Electronic Engineering Beijing University of Posts and TelecommunicationsNo.10 Xitucheng RoadBeijingChina100876 Sarhad University of Science and Information technology PeshawarPakistan. Electrical Engineering Department Iqra University PeshawarPakistan. State Key laboratory of Network and Switching Technology Beijing University of Posts and TelecommunicationsNo.10 Xitucheng RoadBeijing100876China

We propos e a cos t-effective multi-carrier generation technique which minimizes the passive optical access network(PON) costs. In this study replacement of laser array with multi-carrier source at optical line terminal(OLT) side in PON is addressed. With 25-GHz frequency spacing, the generated optical multi-carriers exhibit good tone to noise ratio(TNR) i. e. above 20 d B, and least amplitude difference i. e. 1.5d B. At the OLT, multi-carriers signal based multiplexed differential phase shift keying(DPSK) data from all the channels each having 10 Gbps for downlink is transmitted through 25 km single mode fiber. While the transmitted information is retrieved at optical network unit(ONU), part of the downlink signal is re-modulated using intensity modulated(im) on-off keying(OOK) for upstream transmission at 10-Gbps. Simulation results are in good agreement with the theoretical analysis, showing error free transmission in downlink and uplink with 10 Gbps symmetric data rate at each channel. The receivedpower, both for uplink and downlink transmission, is adequate for all channels at BER of 10-9 with minimum power penalties. Power budget is calculated for different splitting ratios showing excellent system margins for any unseen losses. The proposed setup provides a cost-effective way minimizing transmission losses, and providing greater system's margin in PON architecture.

关键词：多载波信号成本效益无源光接入网 OLT 无噪声差分相移键控 Gbps 光纤传输

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聚合物支撑的ZIF膜材料在气体分离和水体净化领域中的应用

聚合物支撑的ZIF膜材料在气体分离和水体净化领域中的应用

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作者： Ajmal khan（阿杰马勒）北京化工大学

学位级别：硕士

沸石咪唑骨架是由金属单元(例如Zn,Co)和有机连接体组成的多孔开放结晶材料。ZIF中的M-im-M角与Si-O-Si角(145°)类似,这有利于合成大量具有沸石型四面体拓扑的ZIF。由于ZIFs材料具有多孔性和可调结构,其已被广泛应用于气体分离、气体... 详细信息

沸石咪唑骨架是由金属单元(例如Zn,Co)和有机连接体组成的多孔开放结晶材料。ZIF中的M-im-M角与Si-O-Si角(145°)类似,这有利于合成大量具有沸石型四面体拓扑的ZIF。由于ZIFs材料具有多孔性和可调结构,其已被广泛应用于气体分离、气体储存、催化、化学传感器和污水吸附等领域。为了提高应用性,需将沸石咪唑骨架制造成膜材料。由于ZIF膜材料具有出色的分子鉴别能力,因此它们多被用于工业化实际应用中。然而,由于ZIF膜与基材的相互作用性差,晶体间的连续性较差并且膜制造成本高,很大程度上限制了此类材料的应用。此论文的目的是基于沸石咪唑骨架膜的制备,无底物修饰和有底物修饰的有效生长,以及其在气体分离和吸收污染物中的应用。因此,第一章介绍了 ZIF膜的合成,以及不同修饰底物制备方法及在各领域中的应用。第二章中介绍了采用简便有效的方法制备ZIF-8和ZIF-67两种沸石咪唑骨架LDH包覆的PAN-PVDF混合聚合物纤维。通过原位水热法将LDHs(ZnAl-LDH和CoAl-LDH)涂覆在含有电纺聚合物纤维的勃姆石(AlOOH)上。勃姆石(AlOOH)在PAN-PVDF纳米纤维中的直接电纺作用促进了 LDH在纤维上的生长,避免了铝前体长时间加入的溶胶-凝胶涂覆法。用LDH涂层聚合物纤维制造的ZIF具有高连续性并且通过控制温度可构成一种新型多层结构。所制备的聚合物-LDH-ZIF膜可用于将H2与其它气体如CH4/H2,N2/H2和CO2/H2分离。两种ZIFs膜材料均表现出对H2较好的分离性能,ZIF-67对CH4/H2的选择性比ZIF-8的7.6高出12.8倍。理论研究和我们的研究表明,与ZIF-8相比ZIF-67的脆性结构较少同时孔径较窄。第3章描述了在电纺聚合物基底上制造的人肠中以微绒毛状形态排列的多层剥落状ZIF-8。通过对ZIF-8 ZIF提供新形状的有机连接体的缓慢成核来控制制备ZIF。ZIF-8的这种新形状非常类似于人性肠微绒毛结构。这种特殊的ZIF-8结构支持聚合物纤维,以提供功能形状。将聚合物纳米纤维片材直接浸入ZIF前体溶液中,可在聚合物载体上生长厚而均匀的ZIF-8层。ZIF-8的厚度可用时间间隔进行监测(增加时间间隔可以增加厚度)。ZIF聚合物膜通过折叠转化为柱状,以暴露内表面以有效吸收染料。当染料溶液通过ZIF-聚合物柱时,具有高效率和高渗透性的ZIF层析柱可将染料吸附,层间距离提供了高吸附位点。当染料溶液通过普通ZIF-8膜时,也能从溶液中吸附足够的染料,但吸附效率低于剥落状ZIF材料。我们的实验表明ZIF-8的形状变化提高了其吸附能力。

关键词：气体分离金属有机框架层状双氢氧化物静电纺丝剥落状ZIF 染料吸附

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Development of Online Based Smart House Renting Web Application

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Journal of Software Engineering and Applications 2021年第7期14卷 312-328页

作者： Dipta Voumick Prince Deb Sourav Sutradhar Mohammad Monirujjaman khan Department of Electrical and Computer Engineering North South University Dhaka Bangladesh

The house rental issue is one of the elemental parts of society. Nowadays, it is extremely difficult to find suitable accommodation in city areas if people search for it physically. On the other hand, the land owner also needs to rent the house. It can be difficult to find tenants just to hang a lease sign on a building, and as a result, they lose money. An online common platform can play a vital role in this case. The purpose of the study is to develop a common web-based online platform for both tenants and house owners so that both tenants and landowners will mutually benefit from the system. This paper presents the development of web applications for the people of Bangladesh where both house owners and tenants can register and tenants can have houses for rent via sophisticated contact with the house owner. In this paper, a common online-based smart house rental web application has been developed both for tenants and for house owners. This web application is very user-friendly, efficient and it has got many unique features that are not offered by other currently available house rental websites here in Bangladesh. Tenants can register using their phone number, store information about their identity, search for available houses, send messages to house owners, and choose a suitable house using developed web applications. House owners can also register for the system, which will manually verify and authenticate the knowledge provided by the house owner can view a tenant’s information history whenever a tenant makes contact through text and supply house-related information accordingly. The proposed online smart house system has been tested and validated. It works very efficiently with many features. The application provided faster and improved opportunities to get houses, as well as ensuring the availability of houses for rent in the greatest number of areas. The system will help to spread trustworthy services nationwide and supply users with the chance to speak and im

关键词： Web Application Online Platform House Renting Smart Security Advertise Network Remote Interaction

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impact of Exchange Rate on Foreign Trade of Pakistan

Impact of Exchange Rate on Foreign Trade of Pakistan

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作者： Malik Muhammad Bilal khan 南京理工大学

学位级别：硕士

The study empirically investigated the impact of change in exchange rate on Foreign trade of Pakistan for the period 1993 to *** condition states that exchange rate devaluation improves trade balance of a *** econometric methods utilized in the analysis include Johansen cointegration technique and vector error correction model（VECM）*** variables used in study include trade balance（TB）,exchange rate（EXR）,export（EX）and import（im）.Stationarity test was conducted and found stationarity among the variables after first *** estimation of the cointegration test showed evidence of long run relationship among the *** test results of VECM models states that exports of Pakistan are influenced by the exchange rate in the long-term as well as short-term;however,imports are only controlled by the exchange rate in the ***,the study through the application of VECM indicate that exchange rate（EXR）has positive and insignificant impact on exports（EX）and Negative on imports（im）,the study recommends that government may reconsider its exchange rate devaluation position and the results shows that in long-terms exchange rate devaluation may lead to increase in exports and show negative results with imports for Pakistan so government is advised to put more efforts to increase its export which would results in to significant improvement in the trade balance of the country in the long run,and hence,discourage excessive volume of importation observed in the economy.

关键词： exchangerate trade balance exports imports

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Levels, trends and determinants of fecundability in Bangladesh: A comparative study using Bangladesh health and demographic survey (BDHS) data

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Open Journal of Preventive Medicine 2012年第3期2卷 379-389页

作者： Farhana Hoque M. Sekander Hayat khan Aminul Haque Institute of Public Health Heidelberg University Im Neuenheimer Feld 324 69120 Heidelberg Germany. Department of Population Sciences University of Dhaka Dhaka-1000. Bangladesh Institute of Statistical Research and Training University of Dhaka Dhaka-1000. Bangladesh

The concept of fecundability derives its importance for the study of human fertility from the fact that it is one of the principal determinants of fertility and is a major standard by which the impact of fertility regulation can be assessed;very few attempts have been made in Bangladesh for estimating fecundability. This study attempts to evaluate the levels, patterns, and trends of fecundability and identify the factors affecting fecundability in Bangladesh based on national surveys of Bangladesh Demographic and Health Survey (BDHS) 2007-1994. Total 9703 ever married women are included in the bivariate and multivariate analyses which reveal that age at first birth, age at marriage and marital duration play an important role in influencing marriage to first birth interval positively and thus fecundability negatively. Although fecundability in Bangladesh showed an increasing trend, but it is very low compared to developed and developing countries.

关键词： Bangladesh Fecundability Marriage to First Birth Interval Fertility and Logistic Regression

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透明质酸钠联合肉毒毒素在改善不同类型上眼睑凹陷中的应用

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中国校医 2022年第8期36卷 612-616页

作者：陶琳鲁佳莹唐蓉蓉 Aawrish khan 王国宝崔海燕上海时光整形外科医院上海200065 同济大学附属同济医院整形美容外科上海知颜医疗美容门诊部南京医科大学

目的研究透明质酸钠填充与肉毒毒素联合治疗不同类型上睑凹陷的临床疗效。方法选取本院2020—2021年眶周老化求美者147例。采用分层随机方法,将单纯上眼睑凹陷者分为A组、B组,将复合型上睑凹陷者分为C组、D组。B组、D组接受单纯透明... 详细信息

目的研究透明质酸钠填充与肉毒毒素联合治疗不同类型上睑凹陷的临床疗效。方法选取本院2020—2021年眶周老化求美者147例。采用分层随机方法,将单纯上眼睑凹陷者分为A组、B组,将复合型上睑凹陷者分为C组、D组。B组、D组接受单纯透明质酸钠填充,A组、C组采用透明质酸钠与肉毒毒素的联合治疗方案。对比4组上睑凹陷深度及改善值、患者满意度及不良事件发生情况。使用SPSS 21.0进行统计学分析。结果剔除随访脱漏者,最终有效统计132例。治疗后3个月,每组上睑凹陷深度测量值与治疗前比较,差异均有统计学意义(P0.05)。C组(20例)术后3个月上睑凹陷深度平均改善值为(1.72±0.42)cm,优于D组(20例)的(0.82±0.50)cm(t=6.091,P<0.01)。术后10例求美者出现轻微的淤青、肿胀,5例出现丁达尔现象;患者总体满意率为92.42%。结论透明质酸钠填充与肉毒毒素联合治疗不同类型上睑凹陷是一种安全、微创、便捷的治疗方法。与传统单纯的填充治疗相比,联合治疗在改善复合型上眼睑凹陷方面具有更好的疗效,值得临床推广。

关键词：注射美容透明质酸钠肉毒毒素联合治疗上睑凹陷

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