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Constrained Application Protocol (CoAP) is a specialized web transfer protocol, designed for realizing inter-operation with constrained networks and nodes for machine to machine applications like smart energy, building automation,...
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Constrained Application Protocol (CoAP) is a specialized web transfer protocol, designed for realizing inter-operation with constrained networks and nodes for machine to machine applications like smart energy, building automation, etc. As an important ubiquitous application protocol for the future Internet of Things, CoAP will be potentially implemented by a wide range of smart devices to achieve cooperative services. Therefore, a high level of interoperability of CoAP implementations is crucial. In this context, CoAP Plugtest - the first formal CoAP interoperability testing event was held in Paris, March 2012 to motivate vendors to verify the interoperability of their equipments. The event turned to be successful due to our contribution, including the test method and tool. This paper presents the testing method and procedure for the CoAP Plugtest event. To carry out the tests, a set of test objectives concerning the most important properties of CoAP have been selected and used to measure the interoperability of CoAP implementations. The process of verification has been automated by implementing a test validation tool based on the technique of passive testing. By using the test tool, a number of devices were successfully tested.
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Energy demand for active mechanical space cooling is projected to double by 2050. Wider adoption of passive cooling systems can help reduce demand. However, familiarity with these systems remains low, and innovation in the field i...
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Energy demand for active mechanical space cooling is projected to double by 2050. Wider adoption of passive cooling systems can help reduce demand. However, familiarity with these systems remains low, and innovation in the field is constrained due to a lack of cost-effective, accessible performance evaluation methods. This paper reports the design, construction, and commissioning of an affordable, self-contained environmental test chamber. The novel chamber replicates a range of outdoor conditions common in hot, dry regions, making possible year-round testing of reduced-scale prototypes. Data from calibration testing are reported, showing no significant difference in evaporative efficiency when a reduced-scale prototype tested in the chamber is compared with datasets from prior full-scale testing. Analyzing the results using an independent sample two-tailed t-test with a 95% confidence interval found a p-value of 0.75. While measured outlet air velocities for reduced-scale and full-scale prototypes differed to some extent (root mean square error of 0.45 m/s), results were nevertheless deemed comparable due to errors introduced by the rapid change in wind speeds and directions at full scale. Future chamber modifications will correct misalignments between data collected from the two scales and prevent observed increases in the chamber’s relative humidity levels during testing.
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In passive testing a monitor observes the trace (sequence of inputs and outputs) of the system under test (SUT) and checks that this trace satisfies a given property P, potentially triggering a response if an incorrect behaviour i...
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In passive testing a monitor observes the trace (sequence of inputs and outputs) of the system under test (SUT) and checks that this trace satisfies a given property P, potentially triggering a response if an incorrect behaviour is observed. Recent work has explored a variant of passive testing, in which we have a required property P of the traces of the SUT and there is a first-in-first-out (FIFO) network between the SUT and the monitor. The problem here is that the trace observed by the monitor need not be that produced by the SUT. Previous work has shown how such asynchronous passive testing can be performed if the property P is defined by a pair (rho, O-rho) that represents the requirement that if trace rho is produced by the SUT then the next output must be from the set O-rho. This paper generalises the previous work to the case where the property P is defined by a finite automaton. (C) 2016 Elsevier Inc. All rights reserved.
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Routing protocols play an important role in the Internet and the test require- ments are running up. To test routing protocols more efficiently, several enhancing techniques are applied in the protocol integrated test system descr...
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Routing protocols play an important role in the Internet and the test require- ments are running up. To test routing protocols more efficiently, several enhancing techniques are applied in the protocol integrated test system described in this paper. The Implementation Under test is modeled as a black box with windows. The test system is endowed with multiple Channels and multiple ports to test distributed protocols. The test suite and other related Aspects are also extended. Meanwhile, the passive testing is introduced to test, analyze and Manage routing protocols in the production field, which is able to perform the conformance Test, the interoperability test and the performance test.
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The application of in-tissue passive sampling to quantify chemical kinetics in fish bioconcentration experiments was investigated. A passive sampler consisting of an acupuncture needle covered with a PDMS tube was developed togeth...
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The application of in-tissue passive sampling to quantify chemical kinetics in fish bioconcentration experiments was investigated. A passive sampler consisting of an acupuncture needle covered with a PDMS tube was developed together with a method for its deployment in rainbow trout. The time to steady state for chemical uptake into the passive sampler was >1 d, so it was employed as a kinetically limited sampler with a deployment time of 2 h. The passive sampler was employed in parallel with the established whole tissue extraction method to study the elimination kinetics of 10 diverse chemicals in rainbow trout. 4-n-nonylphenol and 2,4,6-tri-tert-butylphenol were close to or below the limit of quantification in the sampler. For chlorpyrifos, musk xylene, hexachlorobenzene, 2,5-dichlorobiphenyl and p,p'-DDT, the elimination rate constants determined with the passive sampler method and the established method agreed within 18%. Poorer agreement (35%) was observed for 2,3,4-trichloroanisole and p-diisopropylbenzene because fewer data were obtained with the passive sampling method due to its lower sensitivity. The work shows that in-tissue passive sampling can be employed to measure contaminant elimination kinetics in fish. This opens up the possibility of studying contaminant kinetics in individual fish, thereby reducing the fish requirements and analytical costs for the determination of bioconcentration factors.
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:Testing for failure of passive transfer (FPT) is common practice, yet there is still confusion around the best tests to use. Worldwide, the most common tests used are IgG concentration, total protein (TP) concentration (measured ...
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:Testing for failure of passive transfer (FPT) is common practice, yet there is still confusion around the best tests to use. Worldwide, the most common tests used are IgG concentration, total protein (TP) concentration (measured in a laboratory or ona refractometer) and gamma glutamyl transferase (GGT) activity. Of these, IgG concentration is the gold standard but is expensive to test. In a recently published study we compared IgG results with laboratory TP, BRIX refractometer results and laboratory GGT, and concluded that of the three test laboratory TP concentration was the best predictor of IgG uptake and GGT the worst. Using a BRIX refractometer was marginally less accurate than laboratory TP testing but its cost and speed advantages meant that it would still be of significant value when evaluating potential FPT problems on farm. This paper describes the process used to come to these conclusions.
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Passive multistatic radar is of great interest in both civilian and military applications due to its numerous advantages. We focus on the target detection problem in passive multistatic radar consisting of a non-cooperative illumi...
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Passive multistatic radar is of great interest in both civilian and military applications due to its numerous advantages. We focus on the target detection problem in passive multistatic radar consisting of a non-cooperative illuminator of opportunity, and several spatially separated surveillance receivers. Two F-test based detectors are proposed for target detection in this passive multistatic radar. They both exhibit a constant false alarm rate with respect to noise power. We drive closed-form expressions for the probability of false alarm of the proposed detector for the case of equal noise power in each receivers. Simulation results illustrate that the proposed detectors achieve satisfactory detection performance without requirement of knowledge about noise power. (C) 2018 Elsevier Inc. All rights reserved.
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The labor-intensive nature of the construction industry requires workers to frequently perform physically demanding manual work, thereby exposing them to the risk of musculoskeletal injury (approximately 31.2 cases per 10,000 full...
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The labor-intensive nature of the construction industry requires workers to frequently perform physically demanding manual work, thereby exposing them to the risk of musculoskeletal injury (approximately 31.2 cases per 10,000 full-time equivalent workers). Exoskeletons and exosuits (collectively called EXOs here) are designed to protect workers from these injuries by reducing exertion and muscle fatigue during work. However, the usability of EXOs in construction is still not clear. This is because extant EXO assessments in construction were mainly conducted in laboratory environments with test participants who are not construction professionals. In this research, we conducted a pilot study to investigate the usability of EXOs in a real construction workplace. Four experienced workers were recruited to push/empty construction gondolas with and without a Back-Support EXO, HeroWear Apex. Three workers were recruited to install/remove wooden blocks between steel studs with and without two Arm-Support EXOs, i.e., Ekso EVO and Hilti EXO-001. Their motions, postures, heart rates, and task completion times were recorded and compared. The workers were also surveyed to gather their attitudes toward the EXO’s usefulness and ease of use. The study results demonstrated that the workers responded to the use of EXOs differently and consequently were not unanimously in favor of EXO adoption in practice. The preliminary results and findings from this pilot study help in building a foundation of understanding to improve EXO products to fit the needs of construction workers and foster EXO-enabled construction tasks in the future.
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Impact tests on weakened streetlights were carried out using a high energy pendulum. The weakening mechanism consists of a circumferential notch at the base of the streetlight. The objective is twofold: firstly to reduce the maxim...
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Impact tests on weakened streetlights were carried out using a high energy pendulum. The weakening mechanism consists of a circumferential notch at the base of the streetlight. The objective is twofold: firstly to reduce the maximum acceleration values during an impact which will lessen the potential injuries of the occupants of the vehicle and secondly to help avoid the installation of protective barriers, necessary when the supporting structure has no mechanical fuse, thus helping the failure with low energy absorption values. The machining of the notch is possible in streetlights already installed in the road, due to the fact that the actual values of the structural stiffness and strength of these structures are much higher than those values typically required by the external loadings (mainly wind actions). These preliminary tests have shown a significant decrease in the two parameters under analysis, maximum acceleration and absorbed energy, when using the circumferential notch. These results suggest it would be beneficial to perform a crash test following EN12767 in order to certify the streetlight. (C) 2015 Elsevier Ltd. All rights reserved.
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