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Open AccessFeature PaperArticle Tuneable Liquid Crystal Micro-Lens Array for Image Contrast Enhancement in a Pixelated Thin Film Photo-Transistor Flat Panel Imager
Micromachines 2017, 8(7), 205; doi:10.3390/mi8070205
Received: 12 June 2017 / Revised: 20 June 2017 / Accepted: 23 June 2017 / Published: 26 June 2017
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Abstract
We propose and demonstrate the concept of using a tuneable liquid crystal micro-lens (LCML) array to improve the image contrast of a pixelated thin film photo-transistor (TFPT) flat panel imager. Such a device can be used to image contents on paper-based media and
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We propose and demonstrate the concept of using a tuneable liquid crystal micro-lens (LCML) array to improve the image contrast of a pixelated thin film photo-transistor (TFPT) flat panel imager. Such a device can be used to image contents on paper-based media and display a magnified version on a flat panel display for elderly or visually impaired people. Practical aspects including device physical geometry, object scattering profile, LC material, and focusing effect of LCML on an object are considered during the design process with the support of ZEMAX simulations. An optimised effective focal length (EFL) has been calculated for the designed LCML to best relay the objects or contents on a paper to the TFPT pixel plane. The designed LCML devices are fabricated with the optimised EFL, and they have good phase depth profiles which are close to a spherical lens profile. Preliminary test results show that the combination of a TFPT imager with an LCML array can make the image contrast more than two times better than that using the TFPT imager alone. The tuneable EFL of the developed LCMLs are useful in the situation where the LCML is not in direct contact with the imaged object. Full article
(This article belongs to the collection Laser Micromachining and Microfabrication)
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Open AccessArticle Analysis of Potential Rockfalls on a Highway at High Slopes in Cold-Arid Areas (Northwest Xinjiang, China)
Sustainability 2017, 9(3), 414; doi:10.3390/su9030414
Received: 12 January 2017 / Revised: 6 March 2017 / Accepted: 8 March 2017 / Published: 10 March 2017
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Abstract
In the steep mountainous areas in northwest Xinjiang, where rock mass is broken seriously due to intense freeze thaw weathering, rockfall is one of the most common geological hazards on highway high slopes. Engineering geological investigations on geological hazards along a segment of
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In the steep mountainous areas in northwest Xinjiang, where rock mass is broken seriously due to intense freeze thaw weathering, rockfall is one of the most common geological hazards on highway high slopes. Engineering geological investigations on geological hazards along a segment of the G219 highway was conducted, indicating that rockfalls on the high slopes threaten the safety of vehicles on the highway seriously. In this study, a combination of field investigations, laboratory experiments and numerical simulation methods was performed to identify unstable high slopes, simulate the rockfall trajectories and assess the rockfall hazard in the study area. The results show that there are five high slopes (i.e., W01, W02, …, W05) where rockfall hazard is extremely serious. Considering both the total kinetic energy and the accumulation rate of blocks, rockfall influence area zonation was performed, leading to the conclusions that the sections of highway on W01 to W05 are located at the medium-intensity low-accumulation zone, high-intensity medium-accumulation zone, high-intensity low-accumulation zone, high-intensity low-accumulation zone and medium-intensity high-accumulation zone, respectively. Based on the analysis, a zonation map was accomplished, which could help engineers select effective mitigation measures against rockfalls to avoid casualty and property losses. Full article
(This article belongs to the Special Issue Risk Assessment and Management)
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Open AccessArticle Integrating Future Land Use Scenarios to Evaluate the Spatio-Temporal Dynamics of Landscape Ecological Security
Sustainability 2016, 8(12), 1242; doi:10.3390/su8121242
Received: 19 October 2016 / Revised: 18 November 2016 / Accepted: 25 November 2016 / Published: 30 November 2016
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Abstract
Urban ecological security is the basic principle of national ecological security. However, analyses of the spatial and temporal dynamics of ecological security remain limited, especially those that consider different scenarios of urban development. In this study, an integrated method is proposed that combines
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Urban ecological security is the basic principle of national ecological security. However, analyses of the spatial and temporal dynamics of ecological security remain limited, especially those that consider different scenarios of urban development. In this study, an integrated method is proposed that combines the Conversion of Land Use and its Effects (CLUE-S) model with the Pressure–State–Response (P-S-R) framework to assess landscape ecological security (LES) in Huangshan City, China under two scenarios. Our results suggest the following conclusions: (1) the spatial and temporal dynamics of ecological security are closely related to the urbanization process; (2) although the average values of landscape ecological security are similar under different scenarios, the areas of relatively high security levels vary considerably; and (3) spatial heterogeneity in ecological security exists between different districts and counties, and the city center and its vicinity may face relatively serious declines in ecological security in the future. Overall, the proposed method not only illustrates the spatio-temporal dynamics of landscape ecological security under different scenarios but also reveals the anthropogenic effects on ecosystems by differentiating between causes, effects, and human responses at the landscape scale. This information is of great significance to decision-makers for future urban planning and management. Full article
(This article belongs to the Section Sustainable Use of the Environment and Resources)
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Open AccessFeature PaperArticle Estimation of Paddy Rice Variables with a Modified Water Cloud Model and Improved Polarimetric Decomposition Using Multi-Temporal RADARSAT-2 Images
Remote Sens. 2016, 8(10), 878; doi:10.3390/rs8100878
Received: 16 August 2016 / Revised: 12 October 2016 / Accepted: 18 October 2016 / Published: 23 October 2016
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Abstract
Rice growth monitoring is very important as rice is one of the staple crops of the world. Rice variables as quantitative indicators of rice growth are critical for farming management and yield estimation, and synthetic aperture radar (SAR) has great advantages for monitoring
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Rice growth monitoring is very important as rice is one of the staple crops of the world. Rice variables as quantitative indicators of rice growth are critical for farming management and yield estimation, and synthetic aperture radar (SAR) has great advantages for monitoring rice variables due to its all-weather observation capability. In this study, eight temporal RADARSAT-2 full-polarimetric SAR images were acquired during rice growth cycle and a modified water cloud model (MWCM) was proposed, in which the heterogeneity of the rice canopy in the horizontal direction and its phenological changes were considered when the double-bounce scattering between the rice canopy and the underlying surface was firstly considered as well. Then, three scattering components from an improved polarimetric decomposition were coupled with the MWCM, instead of the backscattering coefficients. Using a genetic algorithm, eight rice variables were estimated, such as the leaf area index (LAI), rice height (h), and the fresh and dry biomass of ears (Fe and De). The accuracy validation showed the MWCM was suitable for the estimation of rice variables during the whole growth season. The validation results showed that the MWCM could predict the temporal behaviors of the rice variables well during the growth cycle (R2 > 0.8). Compared with the original water cloud model (WCM), the relative errors of rice variables with the MWCM were much smaller, especially in the vegetation phase (approximately 15% smaller). Finally, it was discussed that the MWCM could be used, theoretically, for extensive applications since the empirical coefficients in the MWCM were determined in general cases, but more applications of the MWCM are necessary in future work. Full article
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Open AccessArticle Long-Term Changes in the Water Quality and Macroinvertebrate Communities of a Subtropical River in South China
Water 2015, 7(1), 63-80; doi:10.3390/w7010063
Received: 15 August 2014 / Accepted: 8 December 2014 / Published: 24 December 2014
Cited by 1 | Viewed by 1444 | PDF Full-text (526 KB) | HTML Full-text | XML Full-text
Abstract
Subtropical rivers support a highly diverse array of benthic macroinvertebrates. In this study, by combining historical data and new data, we identified specific changes in the Guanlan River, in South China, from 1981 to 2011, and evaluated the effectiveness of an ecological restoration
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Subtropical rivers support a highly diverse array of benthic macroinvertebrates. In this study, by combining historical data and new data, we identified specific changes in the Guanlan River, in South China, from 1981 to 2011, and evaluated the effectiveness of an ecological restoration project under highly polluted conditions. From 1981 to 2011, the water quality in the Guanlan River underwent three major stages. With the deterioration of water quality, there was an overall decrease in the species number of macroinvertebrates in the Guanlan River, an increase in macroinvertebrate density, and a reduction of the biodiversity, and a reduction of functional feeding groups. In 2011, after five years of comprehensive remediation, the Guanlan River was somewhat improved. Macroinvertebrate biodiversity in the middle reach of the Guanlan River, where a key ecological restoration engineering project was implemented, did not differ significantly from other sites. This finding indicates that the effectiveness of ecological restoration measures in highly polluted rivers, particularly at the reach-scale, is very limited and even ineffective. Full article
Open AccessCommunication One Single Molecule as a Multifunctional Fluorescent Probe for Ratiometric Sensing of Fe3+, Cr3+ and Colorimetric Sensing of Cu2+
Sensors 2015, 15(1), 49-58; doi:10.3390/s150100049
Received: 21 October 2014 / Accepted: 15 December 2014 / Published: 23 December 2014
Cited by 6 | Viewed by 1890 | PDF Full-text (866 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The reagent Rh-C, incorporating a rhodamine moiety and a coumarin backbone and prepared via click chemistry, was developed as the first single molecule for detecting Cu2+, Fe3+ and Cr3+. Its response to Cu2+ in different solutions
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The reagent Rh-C, incorporating a rhodamine moiety and a coumarin backbone and prepared via click chemistry, was developed as the first single molecule for detecting Cu2+, Fe3+ and Cr3+. Its response to Cu2+ in different solutions is visible to the naked eye and it exhibits a ratiometric fluorescence response to Fe3+ in methanol and Cr3+ in acetonitrile. Full article
(This article belongs to the Special Issue Ion Selective Electrodes for Bioavailable Ions)
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Open AccessArticle Analysis of Thermal Performance in a Bidirectional Thermocycler by Including Thermal Contact Characteristics
Micromachines 2014, 5(4), 1445-1468; doi:10.3390/mi5041445
Received: 17 October 2014 / Revised: 21 November 2014 / Accepted: 4 December 2014 / Published: 12 December 2014
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Abstract
This paper illustrates an application of a technique for predicting the thermal characteristics of a bidirectional thermocycling device for polymerase chain reaction (PCR). The micromilling chamber is oscillated by a servo motor and contacted with different isothermal heating blocks to successfully amplify the
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This paper illustrates an application of a technique for predicting the thermal characteristics of a bidirectional thermocycling device for polymerase chain reaction (PCR). The micromilling chamber is oscillated by a servo motor and contacted with different isothermal heating blocks to successfully amplify the DNA templates. Because a comprehensive database of contact resistance factors does not exist, it causes researchers to not take thermal contact resistance into consideration at all. We are motivated to accurately determine the thermal characteristics of the reaction chamber with thermal contact effects existing between the heater surface and the chamber surface. Numerical results show that the thermal contact effects between the heating blocks and the reaction chamber dominate the temperature variations and the ramping rates inside the PCR chamber. However, the influences of various temperatures of the ambient conditions on the sample temperature during three PCR steps can be negligible. The experimental temperature profiles are compared well with the numerical simulations by considering the thermal contact conductance coefficient which is empirical by the experimental fitting. To take thermal contact conductance coefficients into consideration in the thermal simulation is recommended to predict a reasonable temperature profile of the reaction chamber during various thermal cycling processes. Finally, the PCR experiments present that Hygromycin B DNA templates are amplified successfully. Furthermore, our group is the first group to introduce the thermal contact effect into theoretical study that has been applied to the design of a PCR device, and to perform the PCR process in a bidirectional thermocycler. Full article
(This article belongs to the Special Issue Biomedical Microdevices)
Open AccessArticle Large-Scale Battery System Development and User-Specific Driving Behavior Analysis for Emerging Electric-Drive Vehicles
Energies 2011, 4(5), 758-779; doi:10.3390/en4050758
Received: 15 February 2011 / Revised: 26 March 2011 / Accepted: 13 April 2011 / Published: 29 April 2011
Cited by 6 | Viewed by 4115 | PDF Full-text (2300 KB) | HTML Full-text | XML Full-text
Abstract
Emerging green-energy transportation, such as hybrid electric vehicles (HEVs) and plug-in HEVs (PHEVs), has a great potential for reduction of fuel consumption and greenhouse emissions. The lithium-ion battery system used in these vehicles, however, is bulky, expensive and unreliable, and has been the primary roadblock for
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Emerging green-energy transportation, such as hybrid electric vehicles (HEVs) and plug-in HEVs (PHEVs), has a great potential for reduction of fuel consumption and greenhouse emissions. The lithium-ion battery system used in these vehicles, however, is bulky, expensive and unreliable, and has been the primary roadblock for transportation electrification. Meanwhile, few studies have considered user-specific driving behavior and its significant impact on (P)HEV fuel efficiency, battery system lifetime, and the environment. This paper presents a detailed investigation of battery system modeling and real-world user-specific driving behavior analysis for emerging electric-drive vehicles. The proposed model is fast to compute and accurate for analyzing battery system run-time and long-term cycle life with a focus on temperature dependent battery system capacity fading and variation. The proposed solution is validated against physical measurement using real-world user driving studies, and has been adopted to facilitate battery system design and optimization. Using the collected real-world hybrid vehicle and run-time driving data, we have also conducted detailed analytical studies of users’ specific driving patterns and their impacts on hybrid vehicle electric energy and fuel efficiency. This work provides a solid foundation for future energy control with emerging electric-drive applications. Full article
(This article belongs to the Special Issue Hybrid Vehicles)
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Open AccessArticle Protective Effects of Squid Ink Extract Towards Hemopoietic Injuries Induced by Cyclophosphamine
Mar. Drugs 2009, 7(1), 9-18; doi:10.3390/md7010009
Received: 19 September 2008 / Revised: 29 October 2008 / Accepted: 11 December 2008 / Published: 14 January 2009
Cited by 16 | Viewed by 7034 | PDF Full-text (278 KB) | HTML Full-text | XML Full-text
Abstract
To investigate the protective effects of squid ink in chemotherapy, BALB/c mice were used as animal models of injuries induced by cyclophosphamine, a well known chemotherapeutic drug. The mice were randomly divided into five groups with the same number of males and females
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To investigate the protective effects of squid ink in chemotherapy, BALB/c mice were used as animal models of injuries induced by cyclophosphamine, a well known chemotherapeutic drug. The mice were randomly divided into five groups with the same number of males and females in each group. At the end of the experiment, animals were sacrificed to investigate organ indexes and antioxidant ability of the spleen, peripheral blood profile and quantities of bone marrow nucleated cells. Results showed that the hemopoietic function of mice was injured by cyclophosphamine, as indicated by decreases of contents of erythrocytes, leukocytes, hemoglobin and bone marrow nucleated cells (P<0.01), while platelets were not affected (P>0.05), as well as modification of organ indexes (P<0.05) and spleen antioxidant ability (P<0.05 or P<0.01), whereas sepia extract markedly increased the levels of erythrocytes, leukocytes, hemoglobin and bone marrow nucleated cells (P<0.01), but not platelets (P>0.05), and reversed the effects of cyclophosphamine on organ indexes and antioxidant ability of spleen (P<0.01 or P<0.05). In addition, squid ink extract did not change marrow hemopoiesis but improved the antioxidant ability of spleen in the animals. The data suggest that squid ink extract can protect the hemopoietic system from chemotherapeutic injury and could be employed to develop cell-protective drugs for use in clinical treatment of tumours. Full article
(This article belongs to the Special Issue Marine Drugs Studies in China)
Open AccessArticle Comparative and Combinative Study of Urban Heat island in Wuhan City with Remote Sensing and CFD Simulation
Sensors 2008, 8(10), 6692-6703; doi:10.3390/s8106692
Received: 26 March 2008 / Revised: 28 September 2008 / Accepted: 21 October 2008 / Published: 25 October 2008
Cited by 11 | Viewed by 8779 | PDF Full-text (541 KB) | HTML Full-text | XML Full-text
Abstract
Urban heat islands are one of the most critical urban environment heat problems. Landsat ETM+ satellite data were used to investigate the land surface temperature and underlying surface indices such as NDVI and NDBI. A comparative study of the urban heat environment at
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Urban heat islands are one of the most critical urban environment heat problems. Landsat ETM+ satellite data were used to investigate the land surface temperature and underlying surface indices such as NDVI and NDBI. A comparative study of the urban heat environment at different scales, times and locations was done to verify the heat island characteristics. Since remote sensing technology has limitations for dynamic flow analysis in the study of urban spaces, a CFD simulation was used to validate the improvement of the heat environment in a city by means of wind. CFD technology has its own shortcomings in parameter setting and verification, while RS technology is helpful to remedy this. The city of Wuhan and its climatological condition of being hot in summer and cold in winter were chosen to verify the comparative and combinative application of RS with CFD in studying the urban heat island. Full article
(This article belongs to the Special Issue Sensors for Urban Environmental Monitoring)
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Open AccessArticle Dinuclear Zinc (II) Complexes of Macrocyclic Polyamine Ligands Containing an Imidazolium Bridge: Synthesis, Characterization, and Their Interaction with Plasmid DNA
Int. J. Mol. Sci. 2007, 8(7), 606-617; doi:10.3390/i8070606
Received: 6 March 2007 / Revised: 6 June 2007 / Accepted: 14 June 2007 / Published: 4 July 2007
Cited by 7 | Viewed by 6693 | PDF Full-text (251 KB) | HTML Full-text | XML Full-text
Abstract
Two novel macrocyclic polyamine ligands and their dinuclear zinc (II)complexes were synthesized and characterized. Their interaction with plasmid DNA wasstudied by gel electrophoresis and fluorescence quenching experiment. The result showedthat these complexes could bind DNA efficiently under physiological conditions. Full article
(This article belongs to the Special Issue Nucleic Acid Derivatives in Emerging Technologies)

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