Manufacturing Lots Research Articles

Single-dose, live-attenuated Japanese encephalitis vaccine in children aged 12–18 months: Randomized, controlled phase 3 immunogenicity and safety trial

This trial in 1200 JE-vaccination naïve children (age 12–18 mo) in Thailand and the Philippines aimed to demonstrate consistency of three successive industrial scale manufacturing lots of live attenuated Japanese encephalitis chimeric virus vaccine (JE-CV) and consistency between industrial scale manufacturing lots and a fourth, development lot. Children received JE-CV from one of three successive industrial scale lots produced in Thailand (n = 899), or from a fourth development lot produced in the USA (n = 199), or hepatitis A control vaccine (n = 102). Antibodies were assessed by 50% plaque reduction neutralization test (PRNT50) at screening and Day 28. Seroconversion rates (titer of < 10 at baseline and ≥ 10 on Day 28, or a four-fold rise from a baseline titer of ≥ 10) were determined per group. Lot-to-lot consistency of seroconversion rate and GMT was demonstrated between the 3 industrial scale lots, and between these lots and the US lot. Seroconversion rate on pooled data 28 d after JE-CV vaccination (Thai lots) was 95.0% [95% confidence interval (CI); 93.3–96.3]. The safety profile of JE-CV was favorable and comparable with hepatitis A vaccine. There were no serious adverse events related to vaccination. This study demonstrated the consistency of three successive industrial scale JE-CV vaccine lots, as well as consistency with a development lot. The study also demonstrated that a single dose of JE-CV is well tolerated and elicits a high protective immune response, seroconverting 95% of JE-naïve Asian children aged 12–18 mo. ClinicalTrials.gov: NCT00735644

Design of Double T-Shape Accelerometer Based on MEMS

A novel structure is proposed to design accelerometer, that is, two parallel cantilever beams are selected instead of single-beam, which would effectively improve accelerometer’s sensitivity. The novel structure can be integrated fabricated, which is suit for lot manufacturing. The characteristic parameters of the microstructure are analyzed by ANSYS. It can be concluded that the sensitivity is, anti-overload capacity is 1e5g, measuring range is±20g.The microstructure is manufactured by means of the silicon-on-insulator craft and the thickness of the beam is 20 um, the length is 3500 um. The test results show that the resonance frequency is 1840Hz, which is consistent with the results of the calculation and simulation.

Optimal Lot Sizing with Scrap and Random Breakdown Occurring in Backorder Replenishing Period

This paper is concerned with determination of optimal lot size for an economic production quantity model with scrap and random breakdown occurring in backorder replenishing period. In most real-life manufacturing systems, generation of defective items and random breakdown of production equipment are inevitable. To deal with the stochastic machine failures, production planners practically calculate the mean time between failures (MTBF) and establish the robust plan accordingly, in terms of optimal lot size that minimizes total production-inventory costs for such an unreliable system. Random scrap rate is considered in this study, and breakdown is assumed to occur in the backorder filling period. Mathematical modeling and analysis is used and the renewal reward theorem is employed to cope with the variable cycle length. An optimal manufacturing lot size that minimizes the long-run average costs for such an imperfect system is derived. Numerical example is provided to demonstrate its practical usages.

Application of artificial neural network in food classification

Artificial neural network (ANN) classifiers have been successfully implemented for various quality inspection and grading tasks of diverse food products. ANN are very good pattern classifiers because of their ability to learn patterns that are not linearly separable and concepts dealing with uncertainty, noise and random events. In this research, the ANN was used to build the classification model based on the relevant features of beer. Samples of the same brand of beer but with varying manufacturing dates, originating from miscellaneous manufacturing lots, have been represented in the multidimensional space by data vectors, which was an assembly of 12 features (% of alcohol, pH, % of CO 2 etc.). The classification has been performed for two subsets, the first that included samples of good quality beer and the other containing samples of unsatisfactory quality. ANN techniques allowed the discrimination between qualities of beer samples with up to 100% of correct classifications.

Mathematical modeling for determining the replenishment policy for EMQ model with rework and multiple shipments

This paper uses mathematical modeling to determine optimal inventory replenishment policy for the economic manufacturing quantity (EMQ) with rework and multiple shipments. The classic EMQ model considers a continuous inventory issuing policy for satisfying customer’s demands. It also assumes that all products produced are of perfect quality. However, in a real world vendor-buyer integrated environment, multi-shipment policy is practically used in lieu of the continuous issuing approach and generation of random defective items is inevitable. In this study, we assume the reworking of all defective items takes place when the regular production process ends in each cycle. Failure in repair exists; a portion of reworked items fails during the reworking and becomes scrap. The finished items can only be delivered to customers if the whole lot is quality assured at the end of rework. Fixed quantity multiple installments of the finished batch are delivered to customers at a fixed interval of time. Mathematical modeling and analysis are employed in this study for solving such a realistic EMQ model. The long-run average cost function is derived, its convexity is proved, and a closed-form optimal manufacturing lot size is obtained. Two special cases to the proposed model are examined.

Hazardous material inventory reduction at nuclear and high hazard facilities

Trap Door Site (TA-22) hosts current Los Alamos National Laboratory (LANL) operations related to detonator development. The Radioactive Liquid Waste Treatment Facility (TA-50) supports TA-55 and the rest of the Lab by processing radioactive liquid waste. Designated as a Research and Development facility, the LANL Plutonium Facility (TA-55) is capable of small lot manufacturing. These three facilities are managed by the Plutonium Science & Manufacturing Directorate (ADPSM). An assessment of these facilities “as-is” material at risk quantities has been completed. Within TA-55 and TA-50, EPIcode results presented nine worse case scenarios for hazardous materials quantities, respectively. No opportunities for long-term reduction in hazardous materials were necessary at TA-22. A chlorine generator that is acceptable for use at TA-55 would eliminate the classification levels and protective action distances for chlorine. Purchasing potassium hydroxide and sodium hydroxide in containers that weigh 40 pounds or less at TA-55 and hydrochloric acid in 5 gallon containers or less at TA-50 would eliminate classification levels and protective action distances for these chemicals, as well. Pursuing these opportunities will result in a significant reduction of hazardous material containers; from 9 containers to 2. Sodium hydroxide inventory at TA-50 and nitric acid inventory at TA-55 cannot be reduced based on mission-essential needs, i.e., without increasing the overall risk to each facility. In the following report, a Hazardous Material Inventory Reduction approach for ADPSM facilities is outlined, recommendations for future opportunities to reduce chemicals are presented and hazardous material inventories that cannot be reduced based on mission-essential need discussed. Initiatives of this type contribute to ADPSM scientific and technological excellence by increasing operational safety.

In Vitro Comparison of Mechanical and Degradation Properties of Equivalent Absorbable Suture Materials from Two Different Manufacturers

To compare the mechanical, knotting, and absorption properties of 3 synthetic absorbable suture materials (polyglactin 910, polydioxanone, poliglecaprone 25) from 2 different manufacturers (Huaiyin Medical Instruments Co. Ltd. and Ethicon Inc.). Suture material samples from the same manufacturing lot for each suture type and manufacturer. Part 1: 10 samples of each suture were incubated in bovine serum and tested for ultimate load and stiffness at days 0, 1, 7, 14, 21, and 28. Part 2: 10 knotted samples were similarly evaluated, without incubation. Huaiyin polydioxanone had a greater (P<.001) ultimate load on days 0, 1, and 7; and a consistently greater stiffness for the duration of the study, compared with the Ethicon polydioxanone. Ethicon poliglecaprone 25 had a greater ultimate load on days 0, 1, 7 (P<.001); on day 21 Huaiyin had a greater ultimate load. Ethicon poliglecaprone had greater stiffness on days 0, 1, 7 (P<.001). Ethicon polyglactin 910 had a greater (P<.001) ultimate load at all times and a greater stiffness (P<.001) at days 0, 1, 7, and 14 compared with Huaiyin polyglactin 910. Huaiyin polydioxanone and polyglactin 910 had greater knot breaking strengths than Ethicon equivalents (P<.001). Differences in mechanical properties exist between nominally identical suture materials from different manufacturers.

New heuristics for solving the economic lot scheduling problem with reworks

In this study, we are interested in the economic lot scheduling problem (ELSP) that considers manufacturing of the serviceable products and remanufacturing of the rework products. In this paper, we formulate a mathematical model for the ELSP with reworks using the common cycle approach in which only one manufacturing lot and only one rework lot for each product exist during a common cycle. In order to solve this problem, we propose two heuristics that not only search for the optimal cycle time and an optimal production sequence, but also utilize a simple scheduling heuristic to schedule the starting time of all the manufacturing and rework lots so as to minimize the average total costs. The first heuristic is a simple heuristic that employs a 2-opt search to obtain a close-to-optimal production sequence. The second heuristic, which is a refined version of the simple heuristic, employs a bisection search to look for an optimal cycle time. In our numerical experiments, we compare the effectiveness of both heuristics using randomly generated instances.

Development Design of Auto Lens Cover Which is Strong Product in the Outside Environment in Digital Video Camera and Digital Still Camera (Using the Electromagnetic Field Simulation Design of the Electromagnet Actuator)

In the digital video camera and the digital still camera, it is necessary to cover to protect the lens, because lens is prevented being damaged by grit and dust storm etc. of outside environment. There are a lot of manufacturers that has a lot of defective products of the lens cover. Many of lens cover products have caused the defect that the cover doesn't open even if it turns on power. A reason of many causes is as follow. When the grit the dust storm enters to the internal mechanism of the lens cover, the gear doesn't rotate. The lens cover is set to defend the lens from the scratch and protect from dirt and pollution, and to reduce the trouble of the product, but it yields opposite effects. "To defend the lens from the scratch, we want to close the cover firmly at any condition." Is above-mentioned the demand definition of the lens cover really correct really? We pursue a blind spot of the idea and target rationality. We redefine the demand of the lens cover.

Numerical comparison of LED directivity approximation functions for video displays

The approximation functions of the directivity of the light emitting diodes (LED) have been investigated. LEDs used in large scale LED video displays have been studied. LED directional properties among the other parameters define the video display image quality. The simplicity of an approximation function and ease of analytical handling have been targeted. These functions suppose to be used in display directivity engineering. Four candidate approximation functions were identified and their approximation performance analyzed. The evaluation is done on eight different type LEDs’ sample batches. These samples have been chosen to represent the variety of the main colors and the range of the most popular viewing angles used in large scale LED video displays design. The relative intensity approximation root mean square (RMS) error and approximation errors’ cross correlation have been used as performance estimation criteria. The radiometric intensity variation within a manufacturing lot was suggested as lower error bound. Approximation error variance was analyzed for various approximation ranges. Results of four candidate approximation functions’ performance on eight different type LEDs’ are presented.

A new lot-sizing heuristic for manufacturing systems with product recovery

We consider a deterministic model of the manufacturing system with product recovery. Two types of policies for the problem had been proposed in literature, namely the (1, R) policy, in which one manufacturing setup is followed by R remanufacturing setups and the ( P,1) policy, which has P manufacturing setups, following every remanufacturing setup. Teunter (2004) developed heuristics to evaluate the cost for both policies and recommended choosing the better one among them. In this paper, we develop a new class of general ( P, R) policies, where the long-run ratio of the number of manufacturing setups to the number of remanufacturing setups is P/ R. Rather than have P manufacturing setups followed by R remanufacturing setups, we interleave (or intersperse) the setups of the manufacturing lots and the remanufacturing lots in such a way that the buildup of the recoverable inventory is minimized. We develop interleaving based ( P, R) policy heuristics for the problem. Numerical results presented in the paper show that the proposed heuristic outperforms or performs as well as the best of the Teunter (2004) policies for all the problems tested.

Exhumed Geogrid-Reinforced Retaining Wall

An instrumented geogrid-reinforced wall constructed on a highly compressible foundation was deconstructed 16 months after its completion, providing a unique opportunity to exhume and examine the instrumented geogrids that were used to construct the wall. The objectives of this post mortem study were: (1) to inspect the condition of the strain gauges that were attached to the geogrid layers before construction and to verify the reliability of their output; (2) to develop a procedure in which the residual (plastic) strains along exhumed geogrid panels could be determined; and (3) to assess the in situ strain and force distribution along geogrid panels based on the measured residual strains from the exhumed geogrids. After exhumation, it was observed that many of the attached strain gauges failed due to full or partial debonding from the geogrid, thus rendering outputs which potentially underestimated the actual strain. Combining aperture measurements of virgin and exhumed geogrids, all from the same manufacturing lots, enabled the assessment of residual strains following stress relaxation. Laboratory simulation of loading and unloading, including creep and relaxation, yielded a relationship between the measured residual strains and the in situ strain and force distribution; i.e., the residual strain fingerprint provided insight into the behavior of the geogrids within the wall prior to its deconstruction. The mobilized maximum tensile strains in the geogrid panels along the height of the wall were roughly uniform, in the range 4±1%. These findings imply that if the same type of reinforcement had been used throughout the height of the wall, the mobilized force along the height would have been relatively uniform. The back-calculated maximum force in the geogrids indicated that the factor of safety on the long-term strengths of the geogrids ranged from about 1.4 on the stronger/stiffer geogrid to about 1.8 on the weaker/softer geogrid.

Monte Carlo calculated absorbed‐dose energy dependence of EBT and EBT2 film

The absorbed-dose energy dependence of GAFCHROMIC EBT and EBT2 film irradiated in photon beams is studied to understand the shape of the curves and the physics behind them. The absorbed-dose energy dependence is calculated using the EGSnrc-based EGS_chamber and DOSRZnrc codes by calculating the ratio of dose to water to dose to active film layers at photon energies ranging from 3 keV to 18 MeV. These data are compared to the mass energy absorption coefficient ratios and the restricted stopping power ratios of water to active film materials as well as to previous experimental results. In the photon energy range of 100 keV to 18 MeV the absorbed-dose energy dependence is found to be energy independent within +/- 0.6%. However, below 100 keV, the absorbed-dose energy dependence of EBT varies by approximately 10% due to changes in mass energy absorption coefficient ratios of water to film materials, as well as an increase in the number of electrons being created and scattered in the central surface layer of the film. Results are found to disagree with previous experimental studies suggesting the possibility of an intrinsic energy dependence at lower photon energies. For EBT2 film the absorbed-dose energy dependence at low photon energies varies by 50% or 10% depending on the manufacturing lot due to changes in the ratio of mass energy absorption coefficients of the active emulsion layers to water. Caution is recommended when using GAFCHROMIC EBT/EBT2 films at photon energies below 100 keV. It is recommended that the effective atomic number of future films be produced as close to that of water and that thicker active layers are advantageous.

Formation of manufacturing cells in group technology using a genetic algorithm approach

To cope with a high level of product variety and a small manufacturing lot sizes, novel production techniques have immerged aiming at improving productivity and reducing manufacturing costs. Among them, group technology attempts to decentralise the process of production by identifying the elements of the manufacturing process and analysing their attributes. The purpose of this work is to describe a genetic algorithm approach specifically adapted to the cell formation problem, with the objective of minimising the interaction among cells, i.e. the inter-cellular traffic subject to cell size constraints. Machine sequences of operations have been taken into account. A brief overview of genetic algorithms is also presented in the article. Computational results for randomly produced representative problems are included.

Nutrient analysis of sorghum dried distillers grains with solubles from ethanol plants located in the western plains region (2010)

Samples of sorghum dried distillers grains with solubles (DDGS) were collected and analyzed to establish a nutrient database and evaluate the quality and consistency between and within samples taken from 5 ethanol plants in the Western Plains region. Four plants were located in Kansas and 1 in Texas. A total of 21 samples were collected, with 4 plants contributing 4 samples each and 1 plant contributing 5 samples from different manufacturing lots of DDGS. Each sample was analyzed for amino acids, DM, CP, crude fiber, crude fat, ash, NDF, ADF, Ca, P, trace minerals, GE, and starch. In addition, DE, ME, and NE were calculated from the nutrient analysis. Of the 5 plants, 3 produced pure sorghum DDGS samples while 2 produced mixed sorghum and corn DDGS samples, with sorghum representing 60 or 70% of the DDGS. For the pure sorghum DDGS, the overall sample average means for each nutrient on a DM basis were: DM (89.5%), CP (34.2%), crude fat (10.5%), ash (4.4%), NFE (40.3%), crude fiber (10.6%), ADF (26.4%), NDF (35.1%), starch (4.3%), calculated DE (1,560 kcal/lb), calculated ME (1,454 kcal/lb), calculated NE (919 kcal/lb), Ile (1.37%), Leu (3.84%), Lys (0.88%), Met (0.55%), Thr (1.04%), Trp (0.26%), Val (1.67%), Ca (0.01%), and P (0.72%). The mixed DDGS samples' means were generally similar to the pure sorghum DDGS nutrient analysis values. Results of these analyses can be used by nutritionists to better utilize sorghum DDGS in swine diets.; Swine Day, Manhattan, KS, November 18, 2010

Manufacturing Ceramic Tapes and Thick Film Pastes for SOFCs in an ISO 9001 Environment

Cell and stack developers need to obtain volume quantities of materials consistently and economically. Two viable technologies are cast ceramic tapes and thick-film pastes. Engineering, scale-up, and manufacture provide unique challenges. Materials engineered for manufacturability require control from raw material identification to finished product including source qualification, specification development, paste and tape formulation, in-process control, and documentation. Tapes are manufactured in laboratory and prototype volumes. Thin electrolyte tapes present a manufacturing challenge. Data on tapes that fire to full density at thicknesses <12.5µm are shown. Pastes are used for electrolytes, cathodes, anodes, current collectors, and interconnects. Electrolytes must be gas tight. Vehicles required to disperse high surface area powders must burn out to leave dense, uniform films. Cathode and anode pastes require vehicles designed for large area prints. Reproducing pastes despite powder variation is another challenge. Paste properties for multiple manufacturing lots are presented.

National Outbreak ofAcanthamoebaKeratitis Associated with Use of a Contact Lens Solution, United States

An outbreak of Acanthamoeba keratitis, a rare, potentially blinding, corneal infection, was detected in the United States in 2007; cases had been increasing since 2004. A case-control study was conducted to investigate the outbreak. We interviewed 105 case-patients from 30 states and 184 controls matched geographically and by contact lens use. Available contact lenses, cases, solutions, and corneal specimens from case-patients were cultured and tested by molecular methods. In multivariate analyses, case-patients had significantly greater odds of having used Advanced Medical Optics Complete Moisture Plus (AMOCMP) solution (odds ratio 16.9, 95% confidence interval 4.8-59.5). AMOCMP manufacturing lot information was available for 22 case-patients, but none of the lots were identical. Three unopened bottles of AMOCMP tested negative for Acanthamoeba spp. Our findings suggest that the solution was not intrinsically contaminated and that its anti-Acanthamoeba efficacy was likely insufficient. Premarket standardized testing of contact lens solutions for activity against Acanthamoeba spp. is warranted.

Analysis and Subsequent Testing of Cracked Brass Connector Housings

This paper details the examination of brass coaxial cable connectors which exhibited cracks in their outer housings. Failure analysis indicated a brittle failure due to stress corrosion cracking. Two common stress corrosion cracking tests for copper materials were conducted on new connectors from the same manufacturing lot. Failure of these connectors confirmed the observed fracture mode. This paper shows that failure analysis can involve testing to duplicate and confirm failure mode in addition to the requisite examination of failed components. This additional testing can be especially helpful in corrosion-related failures.

Automated, serum-free production of CTX0E03: a therapeutic clinical grade human neural stem cell line

Automation of cell culture processes is necessary to achieve scalable and reproducible manufacture of cell-based therapies. CTX0E03 is a near-clinic neural stem cell line for stroke therapy. The transfer of the CTX0E03 manufacture process from a manual to a completely automated process is demonstrated by (a) adapting the manual process to conform to the automated platform and (b) conducted a large scale (20 x T175 flasks) automated CTX0E03 expansion in accordance with the working bank to drug substance lot manufacture schedule. The automated lot was within the GMP release specification for viability, growth rate, nestin immunoreactivity and transcriptome equivalence.

Analysis of a Large Database of GCL-Geomembrane Interface Shear Strength Results

A database of 534 large-scale direct shear test results was assembled in this study to evaluate the interface shear strength between geosynthetic clay liners (GCLs) and geomembranes (GMs). The tests were conducted between 1992 and 2003 by a single independent laboratory using procedures consistent with current testing standards. The number of results in the database allowed quantification of the impact of GCL type, GM type, normal stress, and procedures for specimen hydration and consolidation on the shear strength of GCL-GM interfaces, as well as identification of sources of shear strength variability. The interface shear strength was found to be sensitive to the type of GCL internal reinforcement, GM polymer, and GM texturing, but not to the GM thickness or manufacturer. On average, the GCL internal shear strength was observed to be higher than the GCL-GM interface shear strength when tested using the same procedures. GCLs sheared internally show similar stress-displacement responses and friction angles to GCL-GM interfaces that incorporate a GCL with the same reinforcement type. Hydration under normal stresses below those used during shearing (followed by a consolidation period) led to higher GCL internal shear strength, but lower GCL-GM interface shear strength, than when hydration was conducted under the shearing normal stress. Such different responses are attributed to bentonite extrusion from the GCL into the interface. Good repeatability of test results was obtained using GCL and GM specimens from the same manufacturing lot, while high variability was obtained using specimens from different lots. GCL-GM interface peak shear strength variability was found to increase linearly with normal stress.