2,755 research outputs found
J Regularization Improves Imbalanced Multiclass Segmentation
We propose a new loss formulation to further advance the multiclass segmentation of cluttered cells under weakly supervised conditions. When adding a Youden's J statistic regularization term to the cross entropy loss we improve the separation of touching and immediate cells, obtaining sharp segmentation boundaries with high adequacy. This regularization intrinsically supports class imbalance thus eliminating the necessity of explicitly using weights to balance training. Simulations demonstrate this capability and show how the regularization leads to correct results by helping advancing the optimization when cross entropy stagnates. We build upon our previous work on multiclass segmentation by adding yet another training class representing gaps between adjacent cells. This addition helps the classifier identify narrow gaps as background and no longer as touching regions. We present results of our methods for 2D and 3D images, from bright field images to confocal stacks containing different types of cells, and we show that they accurately segment individual cells after training with a limited number of images, some of which are poorly annotated
Pengaruh Penambahan HHO Terhadap Kinerja Dan Ionisasi Pembakaran Motor Bensin
This aim of this research was to conduct the effect of HHO which injected into the combustion chamber through the intake manifold of the gasoline four-stroke motorcycle engine. HHO is a mixture of hydrogen and oxygen was produced by water electrolysis process.The experiments were carried out by using the HHO generatorin intake manifold to produced HHO gas, which injected into the combustion chamber. The HHO gas injection was varied of 0 ml/s, 0.75 ml/s, 1.5 ml/s, 2.25 ml/s and 3 ml/s based on the engine shaft revolution (rpm). The engine shaft revolutions were also varied at 1700 rpm, 2200 rpm, 2700 rpm, 3200 rpm, 3700 rpm, and 4200 rpm. The engine performance (power output effectively, SFC, and thermal efficiency), the ionization combustion (burning voltage and burning time) and exhaust gas emissions (HC and CO) were investigated. The results show that the additionof the HHO gascould improve the performance of the gasoline four-stroke engine. The effective of power out-put and thermal efficiency increase as increase the HHO injection.The specific fuel consumption (sfc) was also decreases as increases the HHO injection. The ionization combustion much better, which the voltage products of combustion increase and combustion time decrease as increase the HHO injection. The addition of HHO gas was also improved the quality of exhaust gas emission which are reduce the content of CO and HC gases due tothe HHO enhance the combustion process. The hydrogen gas has a high diffusivity which can improve of the fuel mixing, turbulence and homogeneity. The hydrogen gas has the flamehigh faster than gasoline, therefore its decrease the burning time as increase the HHO injection
Strukturelle und funktionelle Charakterisierung von mikrobiellen Gemeinschaften in ökologisch und konventionell bewirtschafteten Agrarböden
Soil samples from the DOK long-term field trial were investigated to study influences of different farming systems on structure and function of soil microbial communities. The DOK long-term field trial in Switzerland consists of plots managed bio-dynamically (D), bio-organically (O), conventionally (K) and of those which are managed conventionally but only receive mineral fertilizer (M).
In spring 2003 soil samples from these differently managed plots were taken. All investigated fields were planted with winter wheat in 2003, but with different croppings in 2002: potato and maize cultivation, respectively. Analyses of phospholipid fatty acids (PLFA) and phospholipid etherlipids (PLEL) were carried out to determine bacterial, eukaryotic and archaeal phenotypic diversity. By combining this technique with isotope ratio mass spectrometry (GC/MS-C-IRMS) it was possible to analyse simultaneously 13C/12C ratios in PLFA and PLEL biomarkers for functional analyses of the soil microbiota.
First results revealed differences in the total microbial biomass and community structure among the compared farming systems. Furthermore, the incorporation of the maize derived carbon could be detected in several PLFA at the natural abundance level. This may be an indication for the role of different microbial groups during organic matter degradation
Karakteristik Pembakaran CH4 Dengan Penambahan Co2 Pada Model Helle- Shaw Cell Pada Penyalaan Bawah
Along with the development of industrial technologies is rapidly increasing the demand for renewable energy sources becomes a very important consideration. One of the alternative energy is now being developed is the energy derived from organic materials, this is because the organic compounds are classified as renewable energy. One energy technology in accordance with the requirements of the biogas technology. If biogas is purified or cleaned of impurities in this case CO2 is good, he would have the same characteristics as natural gas. How big is the influence of CO2 on heating value (heat) in the combustion process it is necessary to an investigation. one by looking at the characteristics of combustion, both the pattern and pace of rambatnya. Combustor used in this study is a model of Helle-shaw cell measuring 50 x 20 x 1 cm. Variation of the mixture used is the ratio 7,5:1 to 10: 1 with the addition of 10% 20%, 30% CO2. Performed on the ignition of ignition. Observation of the shape and rate of flame propagation is done using a high speed camera. The results showed that the ratio of 7,5:1 to 10: 1 blue color of the flame and the flame propagation speed greater penembahan but with 10% CO2 20%, 30% color changing flame reddish yellow which indicates incomplete combustion occurs, and the smaller the rate of flame propagation. This is influenced by the presence of buoyancy forces generated by the combustion
Delivering Live Multimedia Streams to Mobile Hosts in a Wireless Internet with Multiple Content Aggregators
We consider the distribution of channels of live multimedia content (e.g., radio or TV broadcasts) via multiple content aggregators. In our work, an aggregator receives channels from content sources and redistributes them to a potentially large number of mobile hosts. Each aggregator can offer a channel in various configurations to cater for different wireless links, mobile hosts, and user preferences. As a result, a mobile host can generally choose from different configurations of the same channel offered by multiple alternative aggregators, which may be available through different interfaces (e.g., in a hotspot). A mobile host may need to handoff to another aggregator once it receives a channel. To prevent service disruption, a mobile host may for instance need to handoff to another aggregator when it leaves the subnets that make up its current aggregator�s service area (e.g., a hotspot or a cellular network).\ud
In this paper, we present the design of a system that enables (multi-homed) mobile hosts to seamlessly handoff from one aggregator to another so that they can continue to receive a channel wherever they go. We concentrate on handoffs between aggregators as a result of a mobile host crossing a subnet boundary. As part of the system, we discuss a lightweight application-level protocol that enables mobile hosts to select the aggregator that provides the �best� configuration of a channel. The protocol comes into play when a mobile host begins to receive a channel and when it crosses a subnet boundary while receiving the channel. We show how our protocol can be implemented using the standard IETF session control and description protocols SIP and SDP. The implementation combines SIP and SDP�s offer-answer model in a novel way
The Energy Flux Different Stability Estimation of Hydraulic Flow in a Horizontal Pipeline with Longitudinal Grooves Number Variation
The experimentally research was governed to estimate the external (source) and internal signal combined system without separate each other. Referring to that, the Lumped Parameter System (LPS) analytical modeling method by Matko et al (2001) as looked as possible is significance and accurately to estimate the internal pressure or difference pressure fluctuation of fluid lines. By using the LPS method were known that the horizontal fluid lines dynamic system with longitudinal grooves number variation (in fractal geometry image) for which will be used as an object in this research are fulfilled as a low frequency model class and small gain pressure fluctuation for every measurement acquisition result It's properly in the LPS modeling method, the hydraulic fluid lines should be looked as a compressible fluid and over pass storage of energy charging so the response is not only affected by resistance but also by inductanc e and capacitance of the fluid. The three fluid elements respectively for a pipeline length unit are constant, have positive values eventually and modified as a function of the pipeline hydraulic diameter. It's confirmed that the result could be given to predict the locally linearly stability character of the fluid flow energy flux different between upstream and downstream pipeline positions
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