Defence Technology(防务技术)最新文献

{"title":"Synergistic effect of nitrocellulose coating on structural and reactivity stabilization of ammonium nitrate oxidizer","authors":"Amir Abdelaziz ,&nbsp;Djalal Trache ,&nbsp;Ahmed Fouzi Tarchoun ,&nbsp;Hani Boukeciat ,&nbsp;Yash Pal ,&nbsp;Sourbh Thakur ,&nbsp;Weiqiang Pang ,&nbsp;Thomas M. Klapötke","doi":"10.1016/j.dt.2024.04.017","DOIUrl":"10.1016/j.dt.2024.04.017","url":null,"abstract":"<div><div>The present work aims to stabilize the room temperature allotropic transition of ammonium nitrate (AN) particles utilizing a microencapsulation technique, which involves solvent/non-solvent in which nitrocellulose (NC) has been employed as a coating agent. The SEM micrographs revealed distinct features of both pure AN and NC, contrasting with the irregular granular surface topography of the coated AN particles, demonstrating the adherence of NC on the AN surface. Structural analysis <em>via</em> infrared spectroscopy (IR) demonstrated a successful association of AN and NC, with slight shifts observed in IR bands indicating interfacial interactions. Powder X-ray Diffraction (PXRD) analysis further elucidated the structural changes induced by the coating process, revealing that the NC coating altered the crystallization pattern of its pure form. Thermal analysis demonstrates distinct profiles for pure and coated AN, for which the coated sample exhibits a temperature increase and an enthalpy decrease of the room temperature allotropic transition by 6 °C, and 36%, respectively. Furthermore, the presence of NC coating alters the intermolecular forces within the composite system, leading to a reduction in melting enthalpy of coated AN by ∼39% compared to pure AN. The thermal decomposition analysis shows a two-step thermolysis process for coated AN, with a significant increase in the released heat by about 78% accompanied by an increase in the activation barrier of NC and AN thermolysis, demonstrating a stabilized reactivity of the AN-NC particles. These findings highlight the synergistic effect of NC coating on AN particles, which contributed to a structural and reactive stabilization of both AN and NC, proving the potential application of NC-coated AN as a strategically advantageous oxidizer in composite solid propellant formulations.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 35-43"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141197773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perspectives on additive manufacturing for warhead applications","authors":"Hao Xue ,&nbsp;Qiang Zhou ,&nbsp;Chuan Xiao ,&nbsp;Guangyan Huang","doi":"10.1016/j.dt.2024.02.010","DOIUrl":"10.1016/j.dt.2024.02.010","url":null,"abstract":"<div><div>According to different damage modes, warheads are roughly divided into three types: fragmentation warheads, shaped charge warheads, and penetrating warheads. Due to limitations in material and structural manufacturing, traditional manufacturing methods make it difficult to fully utilize the damage ability of the warhead. Additive manufacturing (AM) technology can fabricate complex structures, with classified materials composition and customized components, while achieving low cost, high accuracy, and rapid production of the parts. The maturity of AM technology has brought about a new round of revolution in the field of warheads. In this paper, we first review the principles, classifications, and characteristics of different AM technologies. The development trends of AM technologies are pointed out, including multi-material AM technology, hybrid AM technology, and smart AM technology. From our survey, PBF, DED, and EBM technologies are mainly used to manufacture warhead damage elements. FDM and DIW technologies are mainly used to manufacture warhead charges. Then, the research on the application of AM technology in three types of warhead and warhead charges was reviewed and the existing problems and progress of AM technologies in each warhead were analyzed. Finally, we summarized the typical applications and look forward to the application prospects of AM technology in the field of warheads.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 225-251"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140199738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of combined blast- and fragments-induced synergetic damage in polyurea coated liquid-filled container","authors":"Chen Tao ,&nbsp;Chong Ji ,&nbsp;Xin Wang ,&nbsp;Juan Gu ,&nbsp;Yuting Wang ,&nbsp;Changxiao Zhao","doi":"10.1016/j.dt.2024.08.009","DOIUrl":"10.1016/j.dt.2024.08.009","url":null,"abstract":"<div><div>Liquid-filled containers (LFC) are widely used to store and transport petroleum, chemical reagents, and other resources. As an important target of military strikes and terrorist bombings, LFC are vulnerable to blast waves and fragments. To explore the protective effect of polyurea elastomer on LFC, the damage characteristics of polyurea coated liquid-filled container (PLFC) under the combined loading of blast shock wave and fragments were studied experimentally. The microstructure of the polyurea layer was observed by scanning electron microscopy, and the fracture and self-healing phenomena were analyzed. The simulation approach was used to explain the combined blast- and fragments-induced on the PLFC in detail. Finally, the effects of shock wave and fragment alone and in combination on the damage of PLFC were comprehensively compared. Results showed that the polyurea reduces the perforation rate of the fragment to the LFC, and the self-healing phenomenon could also reduce the liquid loss rate inside the container. The polyurea reduces the degree of depression in the center of the LFC, resulting in a decrease in the distance between adjacent fragments penetrating the LFC, and an increase in the probability of transfixion and fracture between holes. Under the close-in blast, the detonation shock wave reached the LFC before the fragment. Polyurea does not all have an enhanced effect on the protection of LFC. The presence of internal water enhances the anti-blast performance of the container, and the hydrodynamic ram (HRAM) formed by the fragment impacting the water aggravated the plastic deformation of the container. The combined action has an enhancement effect on the deformation of the LFC. The depth of the container depression was 27% higher than that of the blast shock wave alone; thus, it cannot be simply summarized as linear superposition.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 201-224"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Innovative dispersion techniques of graphene nanoplatelets (GNPs) through mechanical stirring and ultrasonication: Impact on morphological, mechanical, and thermal properties of epoxy nanocomposites","authors":"Vasi Uddin Siddiqui ,&nbsp;S.M. Sapuan ,&nbsp;Mohd Roshdi Hassan","doi":"10.1016/j.dt.2024.04.018","DOIUrl":"10.1016/j.dt.2024.04.018","url":null,"abstract":"<div><div>Graphene nanoplatelets (GNPs) have attracted tremendous interest due to their unique properties and bonding capabilities. This study focuses on the effect of GNP dispersion on the mechanical, thermal, and morphological behavior of GNP/epoxy nanocomposites. This study aims to understand how the dispersion of GNPs affects the properties of epoxy nanocomposite and to identify the best dispersion approach for improving mechanical performance. A solvent mixing technique that includes mechanical stirring and ultrasonication was used for producing the nanocomposites. Fourier transform infrared spectroscopy was used to investigate the interaction between GNPs and the epoxy matrix. The measurements of density and moisture content were used to confirm that GNPs were successfully incorporated into the nanocomposite. The findings showed that GNPs are successfully dispersed in the epoxy matrix by combining mechanical stirring and ultrasonication in a single step, producing well-dispersed nanocomposites with improved mechanical properties. Particularly, the nanocomposites at a low GNP loading of 0.1 wt%, demonstrate superior mechanical strength, as shown by increased tensile properties, including improved Young's modulus (1.86 GPa), strength (57.31 MPa), and elongation at break (4.98). The nanocomposite with 0.25 wt% GNP loading performs better, according to the viscoelastic analysis and flexural properties (113.18 MPa). Except for the nanocomposite with a 0.5 wt% GNP loading, which has a higher thermal breakdown temperature, the thermal characteristics do not significantly alter. The effective dispersion of GNPs in the epoxy matrix and low agglomeration is confirmed by the morphological characterization. The findings help with filler selection and identifying the best dispersion approach, which improves mechanical performance. The effective integration of GNPs and their interaction with the epoxy matrix provides the doorway for additional investigation and the development of sophisticated nanocomposites. In fields like aerospace, automotive, and electronics where higher mechanical performance and functionality are required, GNPs' improved mechanical properties and successful dispersion present exciting potential.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 13-25"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141050493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Continuous-flow columns packed with zero-valent iron and iron sulfide as a feasible strategy to remediate the persistent contaminant nitroguanidine","authors":"Youngjae Yu ,&nbsp;Erika E. Rios-Valenciana ,&nbsp;Robert A. Root ,&nbsp;Reyes Sierra-Alvarez ,&nbsp;Jon Chorover ,&nbsp;Jim A. Field","doi":"10.1016/j.dt.2024.06.001","DOIUrl":"10.1016/j.dt.2024.06.001","url":null,"abstract":"<div><div>The insensitive munitions compound nitroguanidine (NQ) is used by the U.S. Army to avoid unintended explosions. However, NQ also represents an emerging contaminant whose environmental emissions can cause toxicity toward aquatic organisms, indicating the need for effective remediation strategies. Thus, we investigated the feasibility of treating water contaminated with NQ in continuous-flow columns packed with zero-valent iron (ZVI) or iron sulfide (FeS). Initially, the impact of pH on NQ transformation by ZVI or FeS was evaluated in batch experiments. The pseudo first-order rate constant for NQ transformation (<em>k</em>_{1, NQ}) by ZVI was 8–10 times higher at pH 3.0 compared to pH 5.5 and 7.0, whereas similar <em>k</em>_{1, NQ} values were obtained for FeS at pH 5.5–10.0. Based on these findings, the influent pH fed to the ZVI- and FeS-packed columns was adjusted to 3.0 and 5.5, respectively. Both reactors transformed NQ into nitrosoguanidine (NsoQ). Further transformation of NsoQ by ZVI produced aminoguanidine, guanidine, and cyanamide, whereas NsoQ transformation by FeS produced guanidine, ammonium, and traces of urea. ZVI outperformed FeS as a reactive material to remove NQ. The ZVI-packed column effectively removed NQ below detection even after 45 d of operation (490 pore volumes, PV). In contrast, NQ breakthrough (removal efficiency &lt;85%) was observed after 18 d (180 PV) in the FeS-packed column. The high NQ removal efficiency and long service life of the ZVI-packed column (&gt;490 PV) suggest that the technology is a promising approach for NQ treatment in packed-bed reactors and <em>in situ</em> remediation.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 26-34"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141401145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical simulation of the attenuation effect of blast shock waves in tunnels at different altitudes","authors":"Changjiang Liu ,&nbsp;Hujun Li ,&nbsp;Zhen Wang ,&nbsp;Yong He ,&nbsp;Guokai Zhang ,&nbsp;Mingyang Wang","doi":"10.1016/j.dt.2024.07.005","DOIUrl":"10.1016/j.dt.2024.07.005","url":null,"abstract":"<div><div>Traffic engineering such as tunnels in various altitudinal gradient zone are at risk of accidental explosion, which can damage personnel and equipment. Accurate prediction of the distribution pattern of explosive loads and shock wave propagation process in semi-enclosed structures at various altitude environment is key research focus in the fields of explosion shock and fluid dynamics. The effect of altitude on the propagation of shock waves in tunnels was investigated by conducting explosion test and numerical simulation. Based on the experimental and numerical simulation results, a prediction model for the attenuation of the peak overpressure of tunnel shock waves at different altitudes was established. The results showed that the peak overpressure decreased at the same measurement points in the tunnel entrance under the high altitude condition. In contrast, an increase in altitude accelerated the propagation speed of the shock wave in the tunnel. The average error between the peak shock wave overpressure obtained using the overpressure prediction formula and the measured test data was less than 15%, the average error between the propagation velocity of shock waves predicted values and the test data is less than 10%. The method can effectively predict the overpressure attenuation of blast wave in tunnel at various altitudes.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 120-141"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141841193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Current development and future prospects of multi-target assignment problem: A bibliometric analysis review","authors":"Shuangxi Liu ,&nbsp;Zehuai Lin ,&nbsp;Wei Huang ,&nbsp;Binbin Yan","doi":"10.1016/j.dt.2024.09.006","DOIUrl":"10.1016/j.dt.2024.09.006","url":null,"abstract":"<div><div>The multi-target assignment (MTA) problem, a crucial challenge in command control, mission planning, and a fundamental research focus in military operations, has garnered significant attention over the years. Extensively studied across various domains such as land, sea, air, space, and electronics, the MTA problem has led to the emergence of numerous models and algorithms. To delve deeper into this field, this paper starts by conducting a bibliometric analysis on 463 Scopus database papers using CiteSpace software. The analysis includes examining keyword clustering, co-occurrence, and burst, with visual representations of the results. Following this, the paper provides an overview of current classification and modeling techniques for addressing the MTA problem, distinguishing between static multi-target assignment (SMTA) and dynamic multi-target assignment (DMTA). Subsequently, existing solution algorithms for the MTA problem are reviewed, generally falling into three categories: exact algorithms, heuristic algorithms, and machine learning algorithms. Finally, a development framework is proposed based on the \"HIGH\" model (high-speed, integrated, great, harmonious) to guide future research and intelligent weapon system development concerning the MTA problem. This framework emphasizes application scenarios, modeling mechanisms, solution algorithms, and system efficiency to offer a roadmap for future exploration in this area.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 44-59"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Data driven prediction of fragment velocity distribution under explosive loading conditions","authors":"Donghwan Noh ,&nbsp;Piemaan Fazily ,&nbsp;Songwon Seo ,&nbsp;Jaekun Lee ,&nbsp;Seungjae Seo ,&nbsp;Hoon Huh ,&nbsp;Jeong Whan Yoon","doi":"10.1016/j.dt.2024.07.007","DOIUrl":"10.1016/j.dt.2024.07.007","url":null,"abstract":"<div><div>This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition. The fragment resultant velocities are correlated with key design parameters including casing dimensions and detonation positions. The paper details the finite element analysis for fragmentation, the characterizations of the dynamic hardening and fracture models, the generation of comprehensive datasets, and the training of the ANN model. The results show the influence of casing dimensions on fragment velocity distributions, with the tendencies indicating increased resultant velocity with reduced thickness, increased length and diameter. The model's predictive capability is demonstrated through the accurate predictions for both training and testing datasets, showing its potential for the real-time prediction of fragmentation performance.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 109-119"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141847952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of the coupling relationship between projectile size and yarn dimension on the ballistic performance of plain weave fabric","authors":"Kaiying Wang ,&nbsp;Xuan Zhou ,&nbsp;Wenke Ren ,&nbsp;Yiding Wu ,&nbsp;Yilei Yu ,&nbsp;Yi Zhou ,&nbsp;Lizhi Xu ,&nbsp;Guangfa Gao","doi":"10.1016/j.dt.2024.06.016","DOIUrl":"10.1016/j.dt.2024.06.016","url":null,"abstract":"<div><div>Aramid fibers, due to their relatively high inter-yarn friction, high strength, high modulus, and other characteristics, have become a typical representative of flexible anti-ballistic materials in modern warfare. Current research on the anti-penetration of aramid fabrics mostly focuses unilaterally on the structure and performance of aramid fabrics or the shape and size of projectiles, with fewer studies on the coupled effect of both on ballistic performance. This study analyzes how the coupling relationship (or size effect) between the projectile and fiber bundle dimensions affects the fabric ballistic performance from a mesoscopic scale perspective. Taking plain weave aramid fabric as the research object, considering different diameter projectiles, through a large number of ballistic impact tests and numerical simulations, parameters such as ballistic limit velocity, average energy absorption of fabric, and specific energy absorption ratio (average energy absorption of fabric divided by projectile cross-sectional area) are obtained for ballistic performance analysis. The influence law of projectile size on the ballistic performance of high-performance fabrics is as follows: The relative range of fitted ballistic limit velocity at different target positions gradually decreases and then stabilizes as the projectile diameter increases, indicating that the fabric structure effect gradually disappears at a projectile diameter of 12 mm; The average ballistic limit velocity at three impact positions, P1, P2, and P3, provides the corresponding ballistic limit velocity for 1000D aramid fabric, which increases with projectile diameter but the rate of increase slows down at an inflection point, which in this study occurs where the fabric structure effect nearly disappears at a projectile diameter of 12 mm; The energy absorption ratio increases and then decreases as the projectile diameter increases from 4 mm to 20 mm, reaching a peak at the diameter of 12 mm due to the gradual disappearance of the fabric structural effect. The projectile diameter of 12 mm corresponds to the coupling size of 11.159, which provides a size design reference for the macroscopic-based continuum models of aramid plain weave fabrics.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 288-303"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FedCLCC: A personalized federated learning algorithm for edge cloud collaboration based on contrastive learning and conditional computing","authors":"Kangning Yin ,&nbsp;Xinhui Ji ,&nbsp;Yan Wang ,&nbsp;Zhiguo Wang","doi":"10.1016/j.dt.2024.08.015","DOIUrl":"10.1016/j.dt.2024.08.015","url":null,"abstract":"<div><div>Federated learning (FL) is a distributed machine learning paradigm for edge cloud computing. FL can facilitate data-driven decision-making in tactical scenarios, effectively addressing both data volume and infrastructure challenges in edge environments. However, the diversity of clients in edge cloud computing presents significant challenges for FL. Personalized federated learning (pFL) received considerable attention in recent years. One example of pFL involves exploiting the global and local information in the local model. Current pFL algorithms experience limitations such as slow convergence speed, catastrophic forgetting, and poor performance in complex tasks, which still have significant shortcomings compared to the centralized learning. To achieve high pFL performance, we propose FedCLCC: Federated Contrastive Learning and Conditional Computing. The core of FedCLCC is the use of contrastive learning and conditional computing. Contrastive learning determines the feature representation similarity to adjust the local model. Conditional computing separates the global and local information and feeds it to their corresponding heads for global and local handling. Our comprehensive experiments demonstrate that FedCLCC outperforms other state-of-the-art FL algorithms.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"43 ","pages":"Pages 80-93"},"PeriodicalIF":5.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142189172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}