Double Boxes Research Articles

Analysis of Tube-to-Tubesheet Welding in Carbon Steel Heat Exchangers of a Double Plate Header Box.

The rear wall of the header box serves as a tubesheet in heat exchangers of double plate header box. Tube-to-tubesheet welding must be performed using orbital Gas Tungsten Arc Welding (GTAW) with a head extension, which is passed through the corresponding hole in the front wall (plugsheet) of the header box, where the welding machine is supported. In this project, the effect of parallelism deviations between the plugsheet and the tubesheet of carbon steel header box is analyzed to evaluate its influence on the quality of the tube-to-tubesheet welding. Welded tube (SA-210 Gr. A1) to tubesheet (SA-516 Gr. 70) coupons are manufactured simulating the parallelism deviations previously analyzed in two double plate header boxes of air-cooled heat exchangers using two different preheating temperatures. Macrographic analysis is performed in order to evaluate the weld penetration (minimum leak path) and length of the weld leg in tube-to-tubesheet joints. The results obtained show important variations in those parameters when the parallelism deviations are equal to or greater than −1 mm over the theoretical distance as well as when the distance approaches +1 mm or more. Finally, the incorporation of dimensional controls prior to the welding process is discussed and the implementation of improvements in orbital GTAW equipment is recommended as an optimal solution for this kind of heat exchangers.

Experimental Study on Base Piles Bearing Capacity of Qilu Yellow River Bridge

Qilu Yellow River Bridge is located in Jinan City, Shandong Province. The main bridge adopts bored pile foundation with high design bearing capacity. In order to ensure that the bearing capacity of single pile meets the requirements and ensure the safety of the bridge, the double load boxes O-cell test pile method is used to test the bearing capacity of pile before and after grouting. According to the soil layer property around pile, the double load boxes can be loaded optionally and solve the problems in the tradition pile test. The bearing capacity of each pile section is determined. The bearing capacity of pile before grouting is 75255kN, the bearing capacity of pile after grouting is 89100 kN.

Collaborative tracking based on contextual information and local patches

Robust and accurate tracking is a very difficult task in most challenging situations, such as occlusion and background clutter. A collaborative approach based on contextual information and local patches is proposed in this paper. Firstly, we represented the target by using a series of patches, and each patch independently performs a tracking task based on correlation filtering. To identify and utilize reliable patches, we propose a measure by using reliability and stability indices. Secondly, to suppress background noise, we used double bounding boxes to represent the object consists of the background and foreground. Furthermore, a fine search strategy based on the Bayesian inference framework is adopted to enable the proposed tracker can robustly track various appearance changes. To achieve accurate tracking performance in the long-term tracking process, we used the confidence map to distinguish whether the patch is under severe occlusion. The experimental results show that our approach outperforms several existing state-of-the-art algorithms on the challenging benchmark datasheets.

Seismic vulnerability assessment of rectangular cut-and-cover subway tunnels

This study develops fragility curves for rectangular cut-and-cover tunnels from nonlinear frame analyses. Fragility curves are generated for single, double, and triple boxes constructed for the subway system. A wide range of site profiles is used to evaluate the effect of soil characteristics on the calculated fragility curve. The fragility curves are developed for minor, moderate, and extensive damage states. The damage indices defined in a previous study as the ratio of the elastic moment demand to the yield moment at the critical section of the tunnel lining was used in the analyses. Fragility curves of the tunnels are generated in terms of surface peak ground acceleration (PGA), peak ground velocity (PGV), and PGV/Vs30 (Vs30 is the time-averaged shear-wave velocity to 30 m depth). The results highlight that the fragility curve is highly sensitive to the site profile, and that PGA based curves result in the largest scatter. The effect of the site profile is significantly reduced when PGV/Vs30 is used, where the fragility curves for all site profiles fall within a narrower band. This is because both the intensity of the ground motion and the soil stiffness is accounted for in the parameter PGV/Vs30. Considering the importance of site amplification characteristics, it is recommended that PGV/Vs30 be used instead of PGA and PGV in the generation of fragility curves of underground structures. Comparisons also demonstrate that multi-box tunnels are more vulnerable to earthquake damage compared with single box tunnels because the seismic demand is always larger.

Tracing the chronology of neolithic pit and stone box burials in North-eastern Iberia

This paper sets out how to approach the chronology of an archaeological funerary practice, through a specific case study: the Neolithic “Pit Burials” funerary horizon of the northeastern Iberian Peninsula. Towards the end of the fifth millennium cal BC, the communities settled in this region began to systematically bury a large part of their population in individual, occasionally double, pits or stone boxes burials. Clear similarities have been documented with other neolithic European funerary horizons, such as the “Chasséen” in France or the “Cortaillod” in Switzerland, that suggest that it could be a larger-scale phenomenon. However, up to now the chronology of “Pit Burials” has not been fully defined, so describing and explaining this phenomenon both regionally and globally has been difficult. This paper fills this gap by presenting, on the one hand, new unpublished radiocarbon dates, addressing the methodological possibilities of statistical analysis and Bayesian modelling of radiocarbon dates in order to specify the chronology of funerary contexts. The results presented here not only show the chronology of the “Pit Burials”, and its relationship with the other similar European burials, from this methodological point of view for the first time, but also the methodological advantages of these statistical tools in order to specify the chronology of any other archaeological funerary practice.

Eligibility of Lying Boxes at Different THI Levels in a Freestall Barn

Abstract Cattle show a high sensitivity to changeability of microclimate conditions and heat stress that causes changes in the welfare and behaviour of cows. The presented study aimed at determining the relationship between the temperature humidity index (THI) value during the summer period and daily behaviour of dairy cows, including eligibility of lying boxes. All these aspects were measured under real production conditions. The investigated area, where microclimate conditions measurements were conducted, was a free-stall barn with single and double boxes, with manure and feeding alleys, housing 40 Holstein-Friesian cows. Observations were made on the behaviour of the cows based on a preference test concerning their choice of the best areas with respect to three ranges of THI values: neutral (N), warm (W) and hot (H). During the warm and hot period the research demonstrated a positive correlation between the level of THI and the share of standing cows (in period W - P<0.03 and H - P<0.008), and an inversely proportional one between the level of THI with participation of lying down cows (periods: W - P<0.06; H - P<0.004) and the length of their laying bouts in double boxes. The double boxes area was predominantly occupied, whereas single boxes area was the least often used. The occupation of manure alley areas was positively correlated with the level of THI.

THE SYNTHESIS OF THE PLANAR LINKAGES WITH SYMMETRICAL CONFIGURATIONS

The mechanisms that employ symmetrical configurations can be found in the steering mechanisms, double open refrigerator, roof boxes, and double open windows, among others. They are useful for some special applications with kinematic symmetry. There have been studies about the linkage synthesis, especially in the research of planar closed chains, from as early as 1960s. However, no study has focused on the symmetry of planar linkages. Thus, the purpose of this paper is to present a methodology to synthesize the configurations of planar linkages. The systematic methodology can be divided into structure synthesis, configuration synthesis and results produced from three major processes. Finally, four suitable results of up to six-bar linkages can be obtained, for example. The four results include one four-bar linkage and three six-bar linkages.

Robust visual tracking based on hierarchical appearance model

In order to track the target object effectively in the presence of significant appearance variation, e.g., occlusion, scale variation, deformation, fast motion and background clutter, we develop a new approach based on hierarchical appearance model under the Bayesian framework. The proposed approach represents the target at two levels, i.e., the local and the global levels. At the local level, a set of local patches are used to represent the target so as to adapt the changes in appearance. Likelihood defined as the weighted sum of reliability index and stability index is applied to evaluate how likely a patch pertaining to the target. At the global level, the target is represented by using double bounding boxes regarding the foreground and background, respectively. The inner bounding box only contains the target region, and the outer bounding box contains both the target region and the background region surrounding the target. The target model is encoded by using two HSV color histograms with respect to the target and the background, respectively. As this, the drifts can be effectively suppressed in the tracking process. Furthermore, the object position can be estimated by maximizing the likelihood of the target under the Bayesian framework. An experimental study is employed to illustrate the advantages of our proposed approach. The experimental results demonstrate that our method is very effective and performs favorably in comparison to the state-of-the-art trackers in terms of efficiency, accuracy and robustness.

Preservatives and packaging material have an impact on the post-harvest longevity of cut Rosa hybrida L. ‘Kardinal’ flowers

SummaryWe studied the effects of various preservatives (sucrose, ascorbic acid, salicylic acid, and acetylsalicylic acid) alone, or in various combinations, on the post-harvest performance of cut Rosa hybrida L. ‘Kardinal’ flowers. The effects of packaging material, including boxes (used boxes without vents), newspaper, butter paper (a waxy paper used to avoid moisture loss), craft paper (a thin, less-waxy paper used for wrapping floral bunches), cellophane paper, single cardboard boxes with or without a cellophane lining, and standard double cardboard boxes with or without a cellophane lining, were also studied. Among the preservatives, 4% (w/v) sucrose alone, or combined with 100 mg l–1 acetylsalicylic acid, 200 mg l–1 salicylic acid, or 600 mg l–1 ascorbic acid resulted in longer vase-lives (7.1, 5.6, 5.5, or 5.3 d, respectively). Individual or combined applications of ascorbic acid and/or salicylic acid had no effect on vase-life. Stems in deionised (DI) water or 4% (w/v) sucrose alone had larger petal areas and flower diameters compared to all other preservatives. Pulsing with 0.5 mM silver thiosulphate (STS) for 2 h at room temperature further extended the vase-life, maintained flower diameter, increased petal area, and increased the uptake of vase solution during the first 2 d of the vase period. Stems packed in double-cardboard floral boxes lined with cellophane, or cellophane alone, gave a longer vase-life than newspaper, butter paper, or the spent boxes used by growers in the study area. Packaging in single or double cardboard floral boxes, with or without a cellophane lining, maintained flower quality, increased flower diameter, and increased ion leakage from petals (possibly due to the longer vase-life) more than spent boxes, craft paper, butter paper, or newspaper. By increasing the duration of storage from 2 d to 8 d, vase-life and ion leakage decreased from 4.2 d to 2.6 d, and from 102% to 85%, respectively, while subsequent flower diameter increased to 0.61 cm from a decrease of 0.16 cm.

Sustained growth promotion in Arabidopsis with long-term exposure to the beneficial soil bacterium Bacillus subtilis (GB03)

Volatile emissions from the commercial growth promoting soil bacterium Bacillus subtilis (GB03) are effective in augmenting short-term growth, photosynthetic capacity, and salt tolerance in Petri-dish grown Arabidopsis seedlings. In contrast, the impact sustained GB03 volatile exposure on plant growth and development has yet to be examined. Here is provided physical and physiological data establishing that bacterial volatiles induce long-term growth promotion, elevated photosynthetic capacity and iron accumulation, as well as delayed albeit higher seed count compared with water-treated control plants. Plants were grown unrestricted in double Magenta boxes containing solid MS media for up to twelve weeks with GB03 volatiles introduced in separate containers within the chamber so that plant bacterial interactions are only by air-borne transmission. These results establish that GB03 volatiles induce sustained beneficial effects on Arabidopsis growth including robust and extended vegetative growth followed by elevated seed set.

Preventing Mercury Vapor Release from Broken Fluorescent Lamps during Shipping

Fluorescent lamps are estimated to annually release 1 t of mercury into the air in the United States; transport of used lamps may play an important role in these emissions. In 1999, the U.S. Environmental Protection Agency added lamps to the universal waste rule to encourage recycling by allowing shipment to recycling facilities by common carrier. The rules required that lamp packaging must be structurally sound and adequate to prevent breakage but did not address vapor release. In 2005, a requirement was added that packaging must be designed to prevent the escape of mercury into the environment, but this change does not apply to fluorescent lamps. The goal of this research was to compare mercury vapor containment among different packaging configurations. In 10 replicate experiments of 5 different packages containing 40 broken, used, low-mercury lamps, two 6-hr samples of airborne mercury vapor concentrations were taken in a well-mixed sealed chamber held at 83 ±2 °F. Average chamber concentrations ranged from 0.977 mg/m3 for a single cardboard box to 0.004 mg/m3 for a double cardboard box with a plastic-foil laminate bag sandwiched between the boxes. In comparison to the single cardboard box, a single box with an unsealed thin plastic liner lowered mercury concentrations in the chamber by 52%, single or double boxes with a thicker tape-sealed plastic bag lowered concentrations by 90–92%, and a double box with a ziplock plastic-foil laminate bag lowered concentrations by 99.7%. The latter was the only configuration capable of maintaining airborne concentrations below all occupational exposure levels. Standards more specific to mercury containment are needed for packages used to ship fluorescent lamps to recyclers. Results from this study suggest that an effective packaging design should minimize the effect of cuts from broken glass while also preventing the release of mercury vapor from broken lamps.

Gold Nanoparticle Assemblies through Hydrogen-Bonded Supramolecular Mediators

The synthesis of spherical gold nanoparticle assemblies with multicomponent double rosette molecular boxes as mediators is presented. These nine-component hydrogen-bonded supramolecular structures held together by 36 hydrogen bonds induce gold nanoparticle assembly. The morphologies of the nanoparticle assemblies can be tuned easily by changing the quantity of the building block chemisorbed on the nanoparticle surface.

Simulation of the ALTEA experiment on the International Space Station with the Geant 3.21 program

The ALTEA (Anomalous Long Term Effects in Astronauts) project is aimed at the study of the transient and long term effects of cosmic particles on the astronauts’ cerebral functions. The detector will fly on the International Space Station in 2005. Due to the complexity of the detector (12 double silicon detector boxes arranged around the head of the astronaut) it is necessary to have a detailed simulation of the apparatus response to cosmic ray nuclei in order to assess the detector response and its observational capabilities. The ALTEA detector was therefore simulated by using the Geant 3.21 program, by the astronauts’ head described by 64 cubes of water. By using Creme96 program to evaluate the cosmic rays fluxes within the International Space Station we obtained the events distribution and the energy lost in the cubes of water, as well as the expected interaction rates. Furthermore, we calculated the triggered events number per unit of time in the detector. The simulation was also used to develop a technique to recognize the cosmic rays nuclei.

Evaluating multiloop Feynman integrals by Mellin-Barnes representation

The status of analytical evaluation of double and triple box diagrams is characterized. The method of Mellin-Barnes representation as a tool to evaluate master integrals in these problems is advocated. New MB representations for massive on-shell double boxes with general powers of propagators are presented.

Analytical evaluation of dimensionally regularized massive on-shell double boxes

The method of Mellin–Barnes representation is used to calculate dimensionally regularized massive on-shell double box Feynman diagrams contributing to Bhabha scattering at two loops.

A simple controlled-rate freezing method without a rate-controlled programmed freezer provides optimal conditions for both large-scale and small-scale cryopreservation of umbilical cord blood cells.

Umbilical cord blood (CB) is being used as a source of alternative HPCs for transplantation with increasing frequency. The goal of CB banks for unrelated transplantation is to provide good quality-controlled CB units that can be transplanted for HPCs into the largest possible number of patients. Large CB samples in freezing bags wrapped with insulators and small samples in cryotubes placed into double styrene-foam boxes were cryopreserved at -85 degrees C without a rate-controlled freezing machine, followed by storage in the liquid phase of nitrogen. After thawing these cells, the viability and recovery of cells, as well as the recovery rate of HPCs such as CD34+ cells, CFU-GM, and total CFU were evaluated. Measurement of the freezing rate in CB bags and cryotubes demonstrated that this simple method for cryopreservation of CB cells provided optimal conditions for both large-scale and small-scale cryopreservation. Recovery of CB progenitor cells after cryopreservation was also shown to be potentially acceptable when evaluated with CD34+ cells, CFU-GM, and total CFU. These results were comparable to the method using a rate-controlled programmed freezer. A simple method for cryopreservation of CB cells without a rate-controlled programmed freezer could provide a sufficient-enough potential for the transplantability of HPCs after thawing.

Arginine operator binding by heterologous and chimeric ArgR repressors from Escherichia coli and Bacillus stearothermophilus.

Bacillus stearothermophilus ArgR binds efficiently to the Escherichia coli carAB operator, whereas the E. coli repressor binds very poorly to the argCo operator of B. stearothermophilus. In order to elucidate this contradictory behavior between ArgRs, we constructed chimeric proteins by swapping N-terminal DNA-binding and C-terminal oligomerization domains or by exchanging the linker peptide. Chimeras carrying the E. coli DNA-binding domain and the B. stearothermophilus oligomerization domain showed sequence-nonspecific rather than sequence-specific interactions with arg operators. Chimeras carrying the B. stearothermophilus DNA-binding domain and E. coli oligomerization domain exhibited a high DNA-binding affinity for the B. stearothermophilus argCo and E. coli carAB operators and repressed the reporter-gene transcription from the B. stearothermophilus PargCo control region in vitro; arginine had no effect on, and indeed even decreased, their DNA-binding affinity. With the protein array method, we showed that the wild-type B. stearothermophilus ArgR and derivatives of it containing only the exchanged linker from E. coli ArgR or carrying the B. stearothermophilus DNA-binding domain along with the linker and the alpha4 regions were able to bind argCo containing the single Arg box. This binding was weaker than binding to the two-box operator but was no longer arginine dependent. Several lines of observations indicate that the alpha4 helix in the oligomerization domain and the linker peptide can contribute to the recognition of single or double Arg boxes and therefore to the operator DNA-binding specificity in similar but not identical ArgR repressors from two distant bacteria.

Development of a Rapid Technique for the Evaluation of the Response of Brassica napus to Verticillium wilt.

Extensive efforts are being made to develop oilseed rape cultivars with resistance to Verticillium wilt. Evaluation of these cultivars involves either dipping roots of young plants in a conidial suspension followed by replanting in soil, or sowing the seed directly in artificially infested soil. These methods for screening for resistance take a long time and are expensive. The objective of this research was to develop a rapid and reliable method of screening cultivars for resistance to Verticillium wilt. A box test method in which 4-day-old seedlings were inoculated and grown under sterile conditions in double magenta boxes was developed. The Brassica napus cultivars Accord, Express, Hanna, and Libraska were inoculated with isolates of Verticillium longisporum or V. dahliae. The results from the box test method were compared with root-dip inoculation of seedlings grown in a soil mixture under greenhouse conditions. In addition, plants from the box test were randomly selected and transferred to pots containing sterile soil to permit comparison of plants from the box test at similar developmental stage with plants in the root-dip method. Disease evaluation was based on the number of days after transferring seedlings into the boxes that root browning, root and shoot blackening, and wilting of cotyledons developed. Additional disease evaluation was based on a 0 to 5 disease severity scale based on the percentage of wilted leaves (number) and/or the percentage of stunting (mm) of inoculated plants compared with noninoculated plants. Disease severity was higher on Hanna than on Express, and isolates of V. longisporum were more virulent than isolates of V. dahliae. There was a significant correlation (r = 0.93) of disease rating between the traditional root-dip method and the new box test method. Analysis of variance revealed that the interaction between cultivars and isolates was highly significant (P ≤ 0.01), whereas method of inoculation did not affect the results. In the box test, plants were rated after 25 days, which is at least 3.5 times more rapid than the root-dip method.

Systematic assembly of the double molecular boxes: [Cs subset [CpCo(CN)(3)](4)[Cp*Ru](3)] as a tridentate ligand.

Cubic cage compounds composed of Co-CN-Ru linkages have been prepared which illustrate the following features: (i) new motifs for alkali metal ion complexation (i.e., cationic receptors for cations), (ii) a new family of triaza-metalloligands, and (iii) a double box-like cage. The cages are synthesized by the condensation of [CpCo(CN)(3)](-) and [Cp*Ru(NCMe)(3)](+) (cyclopentadienyl, Cp; pentamethylcyclopentadienyl, Cp*) the presence of Cs(+). The species [Cs subset[[CpCo(CN)(3)](4)[Cp*Ru](4)](+) and [Cs subset[[CpCo(CN)(3)](4)[Cp*Ru](3)[Cp*Rh]](2+) illustrate the box-completion reaction Cs subset Co(4)Ru(3) + M (M = Cp*Rh(2+), Cp*Ru(+)). With the naked ion precursors [Na(NCMe)(6)](+) and [Fe(NCMe)(6)](2+), the box-completion reactions afforded [Na[Cs subset[CpCo(CN)(3)](4)[Cp*Ru](3)]](2)](+) and [Fe[Cs subset [CpCo(CN)(3)](4)[Cp*Ru](3)]](2)](2+). These cages provide the first examples, to our knowledge, of the double-box motif.

Analytical results for dimensionally regularized massless on-shell double boxes with arbitrary indices and numerators

We present an algorithm for the analytical evaluation of dimensionally regularized massless on-shell double box Feynman diagrams with arbitrary polynomials in numerators and general integer powers of propagators. Recurrence relations following from integration by parts are solved explicitly and any given double box diagram is expressed as a linear combination of two master double boxes and a family of simpler diagrams. The first master double box corresponds to all powers of the propagators equal to one and no numerators, and the second master double box differs from the first one by the second power of the middle propagator. By use of differential relations, the second master double box is expressed through the first one up to a similar linear combination of simpler double boxes so that the analytical evaluation of the first master double box provides explicit analytical results, in terms of polylogarithms Li a −t/s , up to a=4, and generalized polylogarithms S a, b (− t/ s), with a=1,2 and b=2, dependent on the Mandelstam variables s and t, for an arbitrary diagram under consideration.