Test Pins Research Articles

Development of a sub-channel thermal hydraulic analysis code and its application to lead cooled fast reactor

The most important candidate for 4th generation nuclear system is lead or lead alloy cooled fast reactor. In the design phase of a lead cooled reactor, it is a top priority to finish the analysis work for the core. The detailed sub-channel analysis code KMC-Sub (Keda multi-physics and multi-scale coupling platform) has been developed to analyze steady state thermal hydraulic issues of SNCLFR-100 (Small Modular Lead-cooled Natural Circulation Fast Reactor, which was designed by University of Science and Technology of China). The model used in this code had taken the influence of cross flow into account, both forced and natural circulation can be simulated, to assess the development status of KMC-sub, experimental data from ORNL 19 pin tests (sodium cooled) and CAS 61 rods test (lead bismuth eutectic cooled) are compared to results from the code. The author found that in most flow rate and power density regime, the results coincides well with the tests data. After the V&V work, the code was used to analyze the flow and temperature distribution in important assemblies of SNCLFR-100 core, which showed that the design is reasonable and feasible.

CT Images Are Noninferior to Anatomic Specimens in Teaching Cardiac Anatomy—A Randomized Quantitative Study

PurposeThe new generation’s learning habits demand reforms in the methods by which we teach anatomy. Medical imaging techniques such as CT may offer a solution to help the understanding of complex anatomic structures. Our objective was to assess the noninferiority of using radiologic images in teaching anatomy as opposed to prosections or lecture slides. MethodsSeventy-three first-year medical students were assigned to three experimental groups taught using different approaches: lecture slides (LG), prosections (PG), or radiology images (RG). All three groups received a 2-hour presentation on cardiac anatomy. Three days after the lectures, the participants were subjected to a gross anatomic “pin test” followed by a written theoretical examination to evaluate their knowledge of cardiac anatomy. ResultsWe found a significant difference between the three groups regarding their gross anatomic examination scores (LG: 8.1 ± 4.1, PG: 10.6 ± 3.3, RG: 8.5 ± 3.4, P = .03; Tukey’s honest significant difference: P(LG−PG) = .04, P(PG−RG) = .08, P(LG−RG) = .94), whereas no significant difference was apparent regarding their written theoretical examination scores (LG: 16.6 ± 4.2, PG: 18.6 ± 3.5, RG: 18.3 ± 3.0, P = .13). ConclusionsConcerning gross anatomic knowledge, groups taught using prosections or radiologic images showed no significant difference. Demonstrative materials do not seem to significantly affect the theoretical knowledge of the students. The use of medical imaging techniques could represent a valuable contribution toward teaching anatomy.

Comparison of California Bearing Ratio and Pin Puncture Strength Testing Used in the Evaluation of Geotextiles

Geotextiles are commonly used in pavements, earth retaining structures, and landfills, as well as in other geotechnical applications. The puncture strength test evaluates the ability of geotextiles to withstand stresses and loads during construction, which are among the severe conditions that geotextiles can experience. ASTM has recently replaced the standard pin puncture strength test, D4833, with the California bearing ratio (CBR) puncture strength test, D6241. However, many state departments of transportation and the FHWA still refer to ASTM D4833. Other state departments of transportation refer to ASTM D4833 and to D6241 or provide a list of alternative test methods to be considered in place of either of these tests. The objective of this research was to correlate the CBR and pin puncture strengths for various categories of geotextiles, regardless of weave type and mass per unit area. Five types of polypropylene geotextiles, three nonwoven and two woven, were subjected to testing in accordance with ASTM D4833 and D6241 standard procedures. Ten and 15 samples of each geotextile type were tested with CBR and pin puncture strength tests, respectively. All five types of geotextiles exhibited puncture strength values, whether pin or CBR, which were consistent within each group. Similarly, distinct load-displacement curves were exhibited within each material group. Statistical analyses were conducted to establish a correlation between the CBR and pin puncture strength values. The correlations were successfully used to estimate the CBR puncture strength values from the pin test with reasonable accuracy ( R2 = .78).

無潤滑ディスク DLC の摩擦特性の温度依存性に関する研究

To further increase recording density of disk storage drives, the heat assisted magnetic recording (HAMR) can solve the coercive force problem of thermal fluctuation and is regarded as the key technology for achieving recording density of more than 1Tb/in2 (1)(2). In this technology, it is suggested that there are serious issues for the diamond like carbon (DLC) overcoat on the disk surface. Because that is heated to high temperature with laser beams(2). In this study, first, we measured temperature dependence of friction properties of non-lubricated DLC surface on magnetic disks. Second, we considered the influence of the accumulated smear on test pin surface during the friction test. As a result, it was estimated that the smear on pin surface accumulated by the laser irradiation was originated from the hydrocarbon contamination adsorbed on DLC surface.

An equivalent linear model for shear pin fractures and its experimental verification

For bridges in seismically active areas, lower horizontal bearing stiffnesses are usually designed to reduce structural seismic responses and protect the piers and foundations against earthquake damage. But lower horizontal bearing stiffnesses are not preferred under normal service conditions. In the seismic designs of Chinese bridges, shear pins are extensively integrated into bearings to resist horizontal force and restrict the relative longitudinal displacement between the superstructure and the substructure under normal service conditions. Shear pins are designed to be sheared off in a certain earthquake to activate the seismic isolation mechanism. For lack of a proper constitutive model for shear pin fractures, effects of shear pin fractures have not been considered in current bridge seismic isolation designs yet. In order to establish a constitutive model of seismic isolation bearings considering shear pin fracture effects, shear fracture tests of shear pins were conducted and an equivalent linear model was established. Ultimate deformation and equivalent stiffness of the equivalent linear model are approximately proportional to the diameter of the shear pin, and load capacity is approximately proportional to the square of the diameter of the shear pin. A series of shaking table tests were conducted, and then test results were compared with numerical results calculated with the equivalent linear model. It was found the equivalent linear model was accurate enough and suggested to simulate the effects of shear pin fractures in bridge seismic designs.

Experimental and numerical studies of shear pin fractures based on linear and bilinear models

Shear pins are commonly used elements integrated with seismic isolation bearings to restrict the relative displacement between the superstructure and the substructure. However, constitutive models for seismic isolation bearings used in seismic isolation designs have not considered the effects of shear pin fractures. In order to establish the constitutive model of seismic isolation bearings with shear pin fractures considered, shear fracture tests of shear pins were conducted, and a linear model and a bilinear model for shear pin fractures were established. By comparing numerical results of different models, the linear constitutive model for shear pins was verified to be accurate enough and suggested to simulate the effects of shear pin fractures in seismic isolation designs. DOI: http://dx.doi.org/10.5755/j01.mech.22.4.16159

Pin pull-out behaviour for hybrid metal-composite joints with integrated reinforcements

Hybrid metal-composite joints that integrate pins on the metal adherend are a novel joining concept, and knowledge regarding single pin performance and correlation to multi-pin joint behaviour is critically lacking. Here, we investigate Selective Laser Melting manufactured titanium with pins adhered to carbon fibre-reinforced polymer composite. Single pin specimens under pull-out loading and Mode I crack growth specimens were investigated using experimental, finite element (FE) and analytical methods. We found the pin-composite interfacial strength was 3.5 times higher than comparable carbon fibre z-pins due to excellent adhesion characteristics of the as-manufactured pin surface. Consequently, the pins enabled a 365% increase in Mode I steady-state fracture toughness. We also determined that the enhanced bonding increased the maximum pin load and Mode I initiation fracture toughness by around 250%, with no pin-composite debonding during cure. We lastly show FE models using the pull-out response characterised in single pin tests give excellent predictions of experimental behaviour in multi-pin joints with no additional calibration. The work provides new correlation between pin behaviour in isolation and in multi-pin joints, highlights the importance of strong pin-composite adhesion for joint performance, and demonstrates an analysis methodology suitable for design of pin-reinforced composites and metal-composite hybrid joints.

Parallelized Network-on-Chip-Reused Test Access Mechanism for Multiple Identical Cores

This paper proposes a new network-on-chip (NoC)-reused test access mechanism (TAM) for testing multiple identical cores. It can test multiple cores concurrently and identify faulty cores to derate the chip by excluding the core. In order to minimize the test time, the TAM utilizes the majority value of test response data. All of the cores can thereby be tested in parallel and test costs (in both test pins and test time) are exactly the same as those for a single core. The hardware overhead is minimized by reusing the NoC infrastructures and transfer-counters are designed as a majority analyzer. The experimental results in this paper show that the proposed TAM can test multiple cores in the same time as a single core and with negligible hardware overhead.

Crack formation in cladding under LOCA quench conditions

Loss-of-Coolant-Accident (LOCA) is a design basis accident that is considered in safety analyses for LWR. This paper discusses crack formation in one-side oxidized Zircaloy-4 cladding with LOCA oxidation quench experimental data. Two types of test pins were used in these experiments. One consisted of a Zircaloy-4 cladding tube and alumina pellets. Another comprised a Zircaloy-4 cladding tube alone. The experimental results showed that the fracture load in the latter cases was larger by about 1000N, and cracks in the oxide layer were clearly observed in the former cases but not in the latter cases. This trend suggested that the order of cracks formed in cladding during LOCA quench conditions should be, first in the α-Zr(O) layer, and then in the oxide, finally in the prior-β layer when the fracture of cladding occurs. The formation of cracks in the oxide was considered to be related to the maximum thermal stress generated in the cladding during quench. RANNS computation suggested that the maximum radial temperature difference in the former case tended to be larger than that in the latter case, and the radial temperature difference increases considerably with off-center pellets, which might also affect crack formation.

Area-Efficient Bevel-Edge Termination Techniques for SiC High-Voltage Devices

This paper reviews the bevel-edge termination techniques for silicon carbide (SiC) power devices, such as bevel junction termination extension (JTE), resistive-bevel termination, bevel-assisted JTE, and positive-bevel termination. The proposed bevel-edge termination techniques significantly reduce the chip size for SiC power devices. PiN diodes and test structures were fabricated to quantify the relative performance of the proposed structures. Quantitative comparison in chip size reduction, process schemes, and future research directions is discussed in detail.

Friction Surface Modification by Nanodiamonds of Denotational Synthesis

The paper deals with the technology and equipment for making a hardened antifriction surface layer of machine elements on the basis of using carbon nanomaterials in order to improve wear resistance. The paper presents the results of tribotechnical tests of pins according to standard techniques using an automated system for research.

Representative Scan Architecture

Test power is one of the most challenges faced by Integrated Circuits. The author proposes a general scan chain architecture called Representative Scan (RS). It transforms the scan cells of conventional scan chain or sub-chain into circular shift registers and a representative flip-flop is chosen for each circular shift register, these representative flip-flops are connected serially to setup into the RS architecture. Thus, test data shifting path is shortened, then the switching activity is reduced in the shifting operates. The proposed scan architecture has the similar test power with the multiple scan chain, and only needs same test pins with single scan chain without added test pins. The experimental results show that the proposed scan architecture achieves very low shifting power. For benchmark circuits of ISCAS89, the shifting power of the best architecture of RS is only 0.53%–13.59% of the conventional scan. Especially for S35932, the shifting power on mintest test set is only 0.53% of the corresponding conventional scan. Compared with the conventional scan, the RS only needs to add a multiplexer for each scan cells, and the hardware cost is not high.

Sistem Pakar Dengan Metode Backward Chaining Untuk Pengujian Transistor Di Laboratorium Elektronika

The expert system is an artificial intelligence, expert systems is a program to store and process knowledge for a particular area, that's why they were able to answer questions and solve problems, according to the consensus of the experts. Backward Chainning models in reverse of the hypothesis, a potential or conclusion which must be proved by the facts that support the hypothesis. Backward Chainning also well described in the form of reasoning began with the goal to the subgoal reach the goal of understanding means fulfilling subgoal. Decision tree is the result of a tracking process that can be used to explain the answer to the question of questions. Chainning Backward algorithm uses primary data structure in the formation of the decision tree. In the knowledge base necessary rules which will be stored in the database. For the rules on the formation of the expert system can be made based on the facts mentioned above. To rule pin test rules that generate multimeter to measure the use of transistors is right and wrong. Read the scale rule is a rule of the final results of the test transistors are good, leaking or broken so it can not be used anymore

Effect of normal load on abrasive wear resistance and wear micromechanisms in FeMnAlC alloy and other austenitic steels

Little attention has been paid to the role of stacking fault energy (SFE) in the two-body abrasive wear of austenitic steels. Using a pin-abrasion test with 220 grit garnet paper as the counterbody, three austenitic steels of different SFEs were compared. The steels were: (i) FeMnAlC, (ii) Hadfield steel, and (iii) AISI 316L steel. Following a pre-conditioning procedure, the normal loads on the 3mm diameter test pins were 5N, 10N and 15N, and the sliding speed along a spiral track of total length 430m was 0.158m/s. Data showed that the FeMnAlC steel had a higher wear resistance than AISI 316L steel but lower wear resistance than the Hadfield steel. However, at the highest test load, all three steels had similar wear resistance. The steel with the lowest SFE had the highest abrasive wear resistance and the steel with the highest SFE had the lowest abrasive wear resistance. The main wear mechanisms were microcutting and microploughing. There was a transition from microploughing to microcutting as the normal load was increased.

차량용 SoC의 신뢰성 향상을 위한 CAN 통신 기반의 고장진단 플랫폼 설계

To verify the function of vehicle is becoming more and more difficult because many electronic control units have been embedded in vehicle with development of electronics industry. The reliability of vehicle should be considered above all important because malfunction of vehicle can cause damage of human life. In this paper, defect diagnosis platform based on CAN network is proposed to improve the reliability of vehicle. Reliability of vehicle is significantly increased by adopting the structural test via dedicated test path after manufacturing. Besides, the test cost is reduced because additional test pins are not required.

Assessment of Protective Gloves for Use with Airfed Suits.

Gloves are often needed for hand protection at work, but they can impair manual dexterity, especially if they are multilayered or ill-fitting. This article describes two studies of gloves to be worn with airfed suits (AFS) for nuclear decommissioning or containment level 4 (CL4) microbiological work. Both sets of workers wear multiple layers of gloves for protection and to accommodate decontamination procedures. Nuclear workers are also often required to wear cut-resistant gloves as an extra layer of protection. A total of 15 subjects volunteered to take part in manual dexterity testing of the different gloving systems. The subjects' hands were measured to ensure that the appropriate sized gloves were used. The gloves were tested with the subjects wearing the complete clothing ensembles appropriate to the work, using a combination of standard dexterity tests: the nine-hole peg test; a pin test adapted from the European Standard for protective gloves, the Purdue Pegboard test, and the Minnesota turning test. Specialized tests such as a hand tool test were used to test nuclear gloves, and laboratory-type manipulation tasks were used to test CL4 gloves. Subjective assessments of temperature sensation and skin wettedness were made before and after the dexterity tests of the nuclear gloves only. During all assessments, we made observations and questioned the subjects about ergonomic issues related to the clothing ensembles. Overall, the results show that the greater the thickness of the gloves and the number of layers the more the levels of manual dexterity performance are degraded. The nuclear cut-resistant gloves with the worst level of dexterity were stiff and inflexible and the subjects experienced problems picking up small items and bending their hands. The work also highlighted other factors that affect manual dexterity performance, including proper sizing, interactions with the other garments worn at the time, and the work equipment in use. In conclusion, when evaluating gloves for use in the workplace it is important to use tests that reflect the working environment and always to consider the balance between protection and usability.

Majority-Based Test Access Mechanism for Parallel Testing of Multiple Identical Cores

The increased use of multicore chips diminishes per-core complexity and also demands parallel design and test technologies. An especially important evolution of the multicore chip has been the use of multiple identical cores, providing a homogenous system with various merits. This paper introduces a novel test access mechanism (TAM) for parallel testing of multiple identical cores and identifying faulty cores to derate the chip by excluding it. Instead of typical test response data from the cores, the test output data used in this paper are the majority values, that is, the typical test responses from the cores. All the cores can thereby be tested in parallel and test costs (in both test pins and test time) are exactly the same as for a single core. The proposed TAM can be implemented with on-chip comparators and majority analyzers. The experimental results in this paper show that the proposed TAM can test multiple cores with minimal test pins and test time and with hardware overhead of $ %.

Subungual glomus tumors of the hand: Treated by transungual excision.

Background:Glomus tumors are benign hamartomas arising from the glomus body, mostly occurring in the subungual region of the digits. A triad of excruciating pain, localized tenderness and cold sensitivity is the key to diagnosing these tumors. Two surgical approaches are described in the literature for excision of subungual glomus tumors-transungual and periungual. We reviewed retrospectively the results of subungual glomus tumors of the hand treated by transungual excision.Materials and Methods:Twelve patients (9 females and 3 males) with histopathologically confirmed subungual glomus tumors of the hand were treated by transungual excision at our institute. The mean age of the patients was 40.5 years (range 28–63 years). All patients presented with pain in the nail bed and cold sensitivity. A bluish-brown discoloration was present in 6 patients. Love's pin test was positive in all and Hildreth's test was positive in 8 patients. The mean duration of followup was 38 months (range 8–72 months).Results:All patients had complete pain relief. There was no new nail deformity and no recurrence till last followup. One patient had deformity of the nail preoperatively due to previous surgery, which persisted after excision of the tumor. All of them returned to their preoperative occupation and regained full function of the hand.Conclusions:The transungual approach provides good access to the entire lesion and facilitates complete excision. Contrary to reported literature, we did not find the development of any new nail deformity with this approach.

Context-Dependent Upper Limb Prosthesis Control for Natural and Robust Use.

Pattern recognition and regression methods applied to the surface EMG have been used for estimating the user intended motor tasks across multiple degrees of freedom (DOF), for prosthetic control. While these methods are effective in several conditions, they are still characterized by some shortcomings. In this study we propose a methodology that combines these two approaches for mutually alleviating their limitations. This resulted in a control method capable of context-dependent movement estimation that switched automatically between sequential (one DOF at a time) or simultaneous (multiple DOF) prosthesis control, based on an online estimation of signal dimensionality. The proposed method was evaluated in scenarios close to real-life situations, with the control of a physical prosthesis in applied tasks of varying difficulties. Test prostheses were individually manufactured for both able-bodied and transradial amputee subjects. With these prostheses, two amputees performed the Southampton Hand Assessment Procedure test with scores of 58 and 71 points. The five able-bodied individuals performed standardized tests, such as the box&block and clothes pin test, reducing the completion times by up to 30%, with respect to using a state-of-the-art pure sequential control algorithm. Apart from facilitating fast simultaneous movements, the proposed control scheme was also more intuitive to use, since human movements are predominated by simultaneous activations across joints. The proposed method thus represents a significant step towards intelligent, intuitive and natural control of upper limb prostheses.

How Secure Are Printed Circuit Boards Against Trojan Attacks?

Hardware Trojan attacks at the integrated circuit (IC) level have been studied extensively in recent times. Researchers have analyzed the impact of these attacks and explored possible countermeasures for ICs. However, vulnerability with respect to hardware Trojan attacks at higher levels of system abstraction, e.g., at printed circuit board (PCB) level, have not been reported earlier. Previous studies have covered security of PCBs against piracy and various post-fabrication tampering attacks. JTAG (Joint Test Access Group) and other field programmability features, e.g., probe pins, unused sockets and USB have been extensively exploited by hackers to gain access to internal features of the designs as well as snooping of secret key, collection of test responses, and manipulating JTAG test pins. One instance demonstrated that Xbox can be hacked by disabling the Digital Rights Management (DRM) policy using JTAG. The emerging business model of PCB design and fabrication that favors extensive outsourcing and integration of untrusted components/entities in the PCB life-cycle to lower manufacturing cost, makes hardware Trojan attacks in PCBs highly feasible.