Ding H.,Wuhan Naval University of Engineering |
Guan J.,Wuhan Naval University of Engineering |
Liu N.,Naval University Institute |
Wang G.,Naval University Institute
IEEE Geoscience and Remote Sensing Letters | Year: 2016
For high-resolution radars operating at low grazing angles, sea clutter always exhibits an impulse behavior with heavy tailed statistical property. Presented is a statistical model for spiky sea clutter based on the generalized central limit theory (CLT). Within the compound Gaussian structure, the CLT is adopted in the modeling of the Bragg scattering speckle component, while the generalized CLT is introduced to describe the contribution of spiky scattering component, which has potential in describing the impulse nature of the underlying mean level because of its algebraic (inverse power) tails. Validation results with S- and X-band measured sea clutter data indicate that the proposed model can improve the fitting accuracy of spiky sea clutter effectively, especially in the tail region. © 2004-2012 IEEE.
Hamahashi M.,Geological Survey of Japan |
Tanikawa W.,Japan Agency for Marine - Earth Science and Technology |
Martin K.,Naval University Institute |
Saito S.,Japan Agency for Marine - Earth Science and Technology |
Kimura G.,Tokyo University of Science
Geochemistry, Geophysics, Geosystems | Year: 2017
Subduction of the buoyant Cocos Ridge offshore the Osa Peninsula, Costa Rica substantially affects the upper plate structure through a variety of processes, including outer forearc uplift, erosion, and focused fluid flow. To investigate the nature of a major seismic reflector (MSR) developed between slope sediments (late Pliocene-late Pleistocene silty clay) and underlying higher velocity upper plate materials (late Pliocene-early Pleistocene clayey siltstone), we infer possible mechanisms of sediment removal by examining the consolidation state, microstructure, and zeolite assemblages of sediments recovered from Integrated Ocean Drilling Program Expedition 344 Site U1380. Formation of Ca-type zeolites, laumontite and heulandite, inferred to form in the presence of Ca-rich fluids, has caused porosity reduction. We adjust measured porosity values for these pore-filling zeolites and evaluated the new porosity profile to estimate how much material was removed at the MSR. Based on the composite porosity-depth curve, we infer the past burial depth of the sediments directly below the MSR. The corrected and uncorrected porosity-depth curves yield values of 800±70 m and 900±70 m, respectively. We argue that deposition and removal of this entire estimated thickness in 0.49 Ma would require unrealistically large sedimentation rates and suggest that normal faulting at the MSR must contribute. The porosity offset could be explained with maximum 250±70 m of normal fault throw, or 350±70 m if the porosity were not corrected. The porosity correction significantly reduces the amount of sediment removal needed for the combination of mass movement and normal faulting that characterize the slope in this margin. © 2017. American Geophysical Union. All Rights Reserved.
Chen X.-L.,Yantai Naval Aeronautical and Astronautical University |
Liu N.-B.,Naval University Institute |
Wang G.-Q.,Naval University Institute |
Guan J.,Yantai Naval Aeronautical and Astronautical University |
He Y.,Naval University Institute
Tien Tzu Hsueh Pao/Acta Electronica Sinica | Year: 2014
The attitude of target at sea may vary with the fluctuation of sea surface, which induces the effect of power modulation of radar echo, and also the Doppler reflects time-varying and nonstationary properties. In this paper, micro-Doppler theory is applied to weak target detection within sea clutter, and an algorithm of detecting micro-motion target at sea is proposed via Gaussian short-time fractional Fourier transform (GSTFRFT). Firstly, signal model of target on the sea surface is established including translation and 3-D rotation movements. Then, radar returns are selected based on sea spikes identification for better signal-to-clutter ratio. Moreover, micro-motion signal is enhanced via GSTFRFT, and signature differences between target and sea clutter are utilized for designing constant false alarm ratio detector. Finally, micro-motion signature and instantaneous frequency can be extracted and obtained by filtering in GSTFRFT domain. Simulation results with real datasets validate the effectiveness of the algorithm, which is qualified for detecting weak target in strong sea clutter environment.
Wu J.,Naval University Institute |
Wang G.,Naval University Institute |
Sun D.,Naval University Institute
2014 IEEE Chinese Guidance, Navigation and Control Conference, CGNCC 2014 | Year: 2015
The purpose is to build a more realistic phantom track deception scenario under complex Three-dimensional space. Since the cooperation between Electronic Combat Air Vehicles (ECAVs) are demanding, the optimal control methods are usually simplified for solving the trajectory programming problem, including the constraints, the natural influence, and the error factors and so on. The phantom track generated in this case is an ideal one, which can not reflect the true environment. We take everything into account when building dynamic models for both ECAV and the phantom. Meanwhile, error factors from information security and ECAV positioning are explored. For the trajectory programming, we convert the optimal control problem into a parameter optimization one. Error items are added to the optimized phantom track in certain forms. Simulation results show that the new phantom track appears to be fragmented, but it just meets the actual circs. © 2014 IEEE.
Weuster M.,Naval University Institute
ASAIO Journal | Year: 2015
Cardiopulmonary failure due to drowning with accidental hypothermia (AH) remains a major task for emergency care physicians. In this case series we describe our experience in 9 patients with cardiopulmonary failure after drowning with AH <35°C, who were provided on an emergency basis with extracorporeal life support system (ECLS) or extracorporeal membrane oxygenation (ECMO). Conservative rewarming methods are not considered for this study. Preclinical conditions and protocols were gathered. Surgical reports and clinical data sets were collected. Median age was 24 years (range: 6 to 75 years). Six patients were male. Climatic conditions mostly showed cold to frosty weather. All cases had different preclinical rescue procedures. They reached the emergency department under cardiopulmonary resuscitation (CPR). Indications for ECLS were cardiac arrest, in one case pulmonary failure. Mean CPR duration was 60 min (range: 15 to 120 min). Prior to implantation, the median pH value was 6.9. Two patients could be successfully weaned from the systems. Cause of death was severe neurologic damage in 6 patients and cardiac failure in one patient. The use of ECLS/ECMO is a therapy option for a small range of patients with cardiopulmonary failure due to drowning with AH. Nevertheless, the interval of preclinical rescue remains extensively long. Copyright © 2015 by the American Society for Artificial Internal Organs
Bridger R.S.,Naval University Institute |
Pisula P.,Naval University Institute
2012 Southeast Asian Network of Ergonomics Societies Conference: Ergonomics Innovations Leveraging User Experience and Sustainability, SEANES 2012 | Year: 2012
Naval personnel at sea completed daily diaries in which they recorded sleep quality, eating patterns and problems with mental and physical task performance. The ships were fitted with motion sensors to enable root mean square accelerations of the deck to be recorded in three axes. Six-hour RMS accelerations were computed for different parts of the ship using rigid body assumptions. The questionnaire data were factor analyzed enabling summative scales for physical and cognitive performance to be derived. Logistic regression analysis revealed significant effects of vertical acceleration on physical and cognitive performance, with the strongest effects on physical performance. Preliminary RMS thresholds are proposed to sustain human performance at sea. No effects of motion on food consumption were found. © 2012 IEEE.
PubMed | Naval University Institute
Type: Journal Article | Journal: Current sports medicine reports | Year: 2015
The optimal resuscitation fluid for uncontrolled bleeding and hemorrhagic shock in both pre- and in-hospital settings has been an ongoing controversy for decades. Hemorrhage continues to be a major cause of death in both the civilian and military trauma population, and survival depends on adequacy of hemorrhage control and resuscitation between onset of bleeding and arrival at a medical treatment facility. The terms far-forward and austere are defined, respectively, as the environment where professional health care providers normally do not operate and a setting in which basic equipment and capabilities necessary for resuscitation are often not available. The relative austerity of a treatment setting may be a function of timing rather than just location, as life-saving interventions must be performed quickly before hemorrhagic shock becomes irreversible. Fresh whole blood transfusions in the field may be a feasible life-saving procedure when facing significant hemorrhage.
PubMed | University of Buenos Aires and Naval University Institute
Type: | Journal: Ecology | Year: 2016
In contrast to the classical notion of an increasing biodiversity from the poles to the equator, a number of studies concluded that the diversity of marine species is highest at the middle latitudes, and decreases at the equator. Using a worldwide database critically compiled from 72 surveys (307 species, 4,807 water column and surface sediment samples), we analyzed the latitudinal gradients in species richness (LGSR) of a highly diversified group of marine holoplanktonic protists, the polycystine Radiolaria. Species richness values were corrected for uneven sample coverage and sample size, and contrasted with gradients in 11 environmental variables. Radiolarian species richness decreases from the equator to the poles both in the water column and in the surface sediments and is tightly coupled with temperature throughout the entire thermal range of marine waters. In the tropical Pacific Ocean, a conspicuous east-west gradient in diversity is also associated with temperature. Globally, diversity is negatively correlated with mean annual concentrations of nutrients (N, P, Si) and chlorophyll a. Disagreements with results reported for many other oceanic plankton may stem from the reduction of 3D distributional patterns onto 2D or 1D spaces, to the intermittent mixing of Subtropical and Subpolar species at the middle latitudes, and to a Mid-Domain Effect. The fact that radiolarian LGSR do not show this drop at the equator is partly due to methodological and database-related differences, and probably also in part a reflection of taxon-specific traits.
PubMed | Naval University Institute
Type: Journal Article | Journal: ASAIO journal (American Society for Artificial Internal Organs : 1992) | Year: 2016
Cardiopulmonary failure because of drowning with accidental hypothermia (AH) remains a major task for emergency care physicians. In this case series, we describe our experience in nine patients with cardiopulmonary failure after drowning with AH less than 35C, who were provided on an emergency basis with extracorporeal life support (ECLS) system or extracorporeal membrane oxygenation (ECMO). Conservative rewarming methods are not considered for this study. Preclinical conditions and protocols were gathered. Surgical reports and clinical data sets were collected. Median age was 24 years (range, 6-75 years). Six patients were male. Climatic conditions mostly showed cold to frosty weather. All cases had different preclinical rescue procedures. They reached the emergency department under cardiopulmonary resuscitation (CPR). Indications for ECLS were cardiac arrest, and in one case, pulmonary failure. Mean CPR duration was 60 min (range: 15-120 min). Before implantation, the median pH value was 6.9. Two patients could be successfully weaned from the systems. Cause of death was severe neurologic damage in six patients and cardiac failure in one patient. The use of ECLS/ECMO is a therapy option for a small range of patients with cardiopulmonary failure because of drowning with AH. Nevertheless, the interval of preclinical rescue remains extensively long.
PubMed | Naval University Institute
Type: Journal Article | Journal: The journal of trauma and acute care surgery | Year: 2015
The last decade of military trauma care has emphasized the role of blood products in the resuscitation of hemorrhaging patients. Damage-control resuscitation advocates decreased crystalloid use and reintroduces blood components as primary resuscitative fluids. The systematic use of blood products have been described in military settings, but reports describing the use of freeze dried plasma (FDP) or red blood cells (RBCs) in civilian prehospital care are few. We describe our preliminary results after implementing RBCs and FDP into our Helicopter Emergency Medical Service (HEMS).We collected data on the use of FDP (LyoPlas N-w (AB)) during a 12-month period from May 31, 2013, to May 30, 2014, before RBC (0Rh (D) negative) introduction in June 2014. FDP and RBCs were indicated in trauma and medical patients presenting with clinical significant hemorrhage on scene. Data were obtained from HEMS registry and patient records.Our preliminary results show that FDP was used in 16 patients (88% males) during the first year. Main patient categories were blunt trauma (n = 5), penetrating trauma (n = 4), and nontrauma (n = 7). Ten patients (62%) were hypotensive with systolic blood pressures less than 90 mm Hg on scene. The majority (75%) received tranexamic acid. Of 14 patients admitted to the hospital, 11 received emergency surgery and 8 needed additional transfusions within the first 24 hours. No transfusion-related complications were recorded. Two of the FDP patients died on scene, and the remaining 14 patients were alive after 30 days. Early results from the recent introduction of RBC show that RBCs were given to four patients. Two patients (one penetrating trauma and one blunt trauma patient) died on scene because of exsanguination, while additional two patients (one blunt trauma patient and one with ruptured aortic aneurism) survived to hospital discharge.Our small study indicates that introduction of FDP into civilian HEMS seems feasible and may be safe and that logistical and safety issues for the implementation of RBCs are solvable. FDP ensures both coagulation factors and volume replacement, has a potentially favorable safety profile, and may be superior to other types of plasma for prehospital use. Further prospective studies are needed to clarify the role of FDP (and RBCs) in civilian prehospital hemorrhagic shock resuscitation and to aid the development of standardized protocols for prehospital use of blood products.Therapeutic study, level V.