Multifunctional photonic integrated circuit for diverse microwave signal generation, transmission and processing

Microwave photonics (MWP) studies the interaction between microwave and optical waves for the generation, transmission and processing of microwave signals (i.e., three key domains), taking advantages of broad bandwidth and low loss offered by modern photonics. Integrated MWP using photonic integrated circuits (PICs) can reach a compact, reliable and green implementation. Most PICs, however, are recently developed to perform one or more functions restricted inside a single domain. In this paper, as highly desired, a multifunctional PIC is proposed to cover the three key domains. The PIC is fabricated on InP platform by monolithically integrating four laser diodes and two modulators. Using the multifunctional PIC, seven fundamental functions across microwave signal generation, transmission and processing are demonstrated experimentally. Outdoor field trials for electromagnetic environment surveillance along an in-service high-speed railway are also performed. The success to such a PIC marks a key step forward for practical and massive MWP implementations.Comment: 17 page

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216

Ensemble Learning-Based Pulse Signal Recognition: Classification Model Development Study

BackgroundIn pulse signal analysis and identification, time domain and time frequency domain analysis methods can obtain interpretable structured data and build classification models using traditional machine learning methods. Unstructured data, such as pulse signals, contain rich information about the state of the cardiovascular system, and local features of unstructured data can be extracted and classified using deep learning. ObjectiveThe objective of this paper was to comprehensively use machine learning and deep learning classification methods to fully exploit the information about pulse signals. MethodsStructured data were obtained by using time domain and time frequency domain analysis methods. A classification model was built using a support vector machine (SVM), a deep convolutional neural network (DCNN) kernel was used to extract local features of the unstructured data, and the stacking method was used to fuse the above classification results for decision making. ResultsThe highest average accuracy of 0.7914 was obtained using only a single classifier, while the average accuracy obtained using the ensemble learning approach was 0.8330. ConclusionsEnsemble learning can effectively use information from structured and unstructured data to improve classification accuracy through decision-level fusion. This study provides a new idea and method for pulse signal classification, which is of practical value for pulse diagnosis objectification

Carcinogenicity Prediction of Noncongeneric Chemicals by a Support Vector Machine

The ability to identify carcinogenic compounds is of fundamental importance to the safe application of chemicals. In this study, we generated an array of <i>in silico</i> models allowing the classification of compounds into carcinogenic and noncarcinogenic agents based on a data set of 852 noncongeneric chemicals collected from the Carcinogenic Potency Database (CPDBAS). Twenty-four molecular descriptors were selected by Pearson correlation, F-score, and stepwise regression analysis. These descriptors cover a range of physicochemical properties, including electrophilicity, geometry, molecular weight, size, and solubility. The descriptor <i>mutagenic</i> showed the highest correlation coefficient with carcinogenicity. On the basis of these descriptors, a support vector machine-based (SVM) classification model was developed and fine-tuned by a 10-fold cross-validation approach. Both the SVM model (Model A1) and the best model from the 10-fold cross-validation (Model B3) runs gave good results on the test set with prediction accuracy over 80%, sensitivity over 76%, and specificity over 82%. In addition, extended connectivity fingerprints (ECFPs) and the Toxtree software were used to analyze the functional groups and substructures linked to carcinogenicity. It was found that the results of both methods are in good agreement

A multifunctional photonic integrated circuit for diverse microwave signal generation, transmission and processing

Microwave photonics (MWP) studies the interaction between microwaves and optical waves for the generation, transmission, and processing of microwave signals (i.e., three key domains), taking advantage of the broad bandwidth and low loss offered by modern photonics. Integrated MWP using photonic integrated circuits (PICs) can reach a compact, reliable, and green implementation. Most PICs, however, are recently developed to perform one or more functions restricted inside a single domain. Herein, as highly desired, a multifunctional PIC is proposed to cover the three key domains. The PIC is fabricated on an InP platform by monolithically integrating four laser diodes and two modulators. Using the multifunctional PIC, seven fundamental functions across microwave signal generation, transmission, and processing are demonstrated experimentally. Outdoor field trials for electromagnetic environment surveillance along in-service high-speed railways are also performed. The success of such a PIC marks a key step forward for practical and massive MWP implementations

A multifunctional photonic integrated circuit for diverse microwave signal generation, transmission and processing

\u3cp\u3eMicrowave photonics (MWP) studies the interaction between microwaves and optical waves for the generation, transmission, and processing of microwave signals (i.e., three key domains), taking advantage of the broad bandwidth and low loss offered by modern photonics. Integrated MWP using photonic integrated circuits (PICs) can reach a compact, reliable, and green implementation. Most PICs, however, are recently developed to perform one or more functions restricted inside a single domain. Herein, as highly desired, a multifunctional PIC is proposed to cover the three key domains. The PIC is fabricated on an InP platform by monolithically integrating four laser diodes and two modulators. Using the multifunctional PIC, seven fundamental functions across microwave signal generation, transmission, and processing are demonstrated experimentally. Outdoor field trials for electromagnetic environment surveillance along in-service high-speed railways are also performed. The success of such a PIC marks a key step forward for practical and massive MWP implementations.\u3c/p\u3

Reconstructing the western boundary variability of the Western Pacific Subtropical High over the past 200years via Chinese cave oxygen isotope records

Cave oxygen isotope (O-18) records have been important in characterizing Asian Monsoon variations on a wide range of timescales. The climatic significance of the O-18 proxy of the cave records and its main control factors, however, remain hotly debated, especially with respect to annual to decadal timescales. In particular, while the spatial and intensity variations of the Western Pacific Subtropical High (WPSH) affects the East Asian Monsoon remarkably on annual to decadal timescales, cave records up to present do not show clear evidence of the WPSH signal. Here we report a new high-resolution (average of 1.5months) O-18 record from Dongshiya Cave, Qinling Mountain, central China. The region is highly sensitive to variations in the position of the WPSH western boundary, which in turn regulates the alternation of dominant moisture sources between the proximal Pacific Ocean and the remote Indian Ocean. Together with another cave record near the WPSH western boundary, we established a new index to reconstruct variations of the WPSH western boundary over the past 200years. Our new data revealed two significant periodicities, 12 and 2-7years respectively, that can be causally linked to solar and ENSO variances correspondingly

A novel small molecule inhibitor of MDM2-p53 (APG-115) enhances radiosensitivity of gastric adenocarcinoma

Abstract Background Gastric cancer is the leading cause of cancer related death worldwide. Radiation alone or combined with chemotherapy plays important role in locally advanced and metastatic gastric adenocarcinoma. MDM2–p53 interaction and downstream signaling affect cellular response to DNA damage which leads to cell cycle arrest and apoptosis. Therefore, restoring p53 function by inhibiting its interaction with MDM2 is a promising therapeutic strategy for cancer. APG-115 is a novel small molecule inhibitor which blocks the interaction of MDM2 and p53. In this study, we investigated that the radiosensitivity of APG-115 in gastric adenocarcinoma in vitro and in vivo. Methods The role of APG-115 in six gastric cancer cells viability in vitro was determined by CCK-8 assay. The expression level of MDM2, p21, PUMA and BAX in AGS and MKN45 cell lines was measured via real-time PCR (RT-PCR). The function of treatment groups on cell cycle and cell apoptosis were detected through Flow Cytometry assay. Clonogenic assays were used to measure the radiosensitivity of APG-115 in p53 wild type gastric cancer cell lines. Western blot was conducted to detect the protein expressions of mdm2-p53 signal pathway. Xenograft models in nude mice were established to explore the radiosensitivity role of APG-115 in gastric cancer cells in vivo. Results We found that radiosensitization by APG-115 occurred in p53 wild-type gastric cancer cells. Increasing apoptosis and cell cycle arrest was observed after administration of APG-115 and radiation. Radiosensitivity of APG-115 was mainly dependent on MDM2-p53 signal pathway. In vivo, APG-115 combined with radiation decreased xenograft tumor growth much more significantly than either single treatment. Moreover, the number of proliferating cells (Ki-67) significantly decreased in combination group compared with single treatment group. Conclusions In summary, we found that combination of MDM2-p53 inhibitor (APG-115) and radiotherapy can enhance antitumor effect both in vitro and in vivo. This is the first report on radiosensitivity of APG-115 which shed light on clinical trial of the combination therapy of radiation with APG-115 in gastric adenocarcinoma