Longer Test Period Research Articles

Gear contact fatigue life prediction based on transfer learning

The gear contact fatigue test is characterised by extraordinarily high costs and a long period of testing. A transfer learning algorithm was applied to develop a gear contact fatigue life prediction strategy to fully use other low-cost fatigue test data, such as twin-disc test data. The twin-disc contact fatigue test data were incorporated into the neural network model to explore the combined effects of surface integrity and stress level on fatigue life, which was further transferred for gear contact fatigue life prediction. The results indicate that this method enables an effective gear fatigue life prediction under minor gear sample conditions. With a small sample amount of 7, the prediction error in the fatigue life of the model with transfer learning is 46.33%, while the typical back-propagation neural network (BPNN) model without transfer learning is 101.66%. To control life prediction error to within 50%, the model without transfer learning requires at least 17 gear samples, while the transfer model calls for only 7 gear samples. The proposed data transfer learning framework can be used to predict the gear contact fatigue S-N curve under minor sample conditions and is straightforwardly applied to extended applications.

Improved wear resistance and recycling of carbon fiber/epoxy composites via incorporation of regenerated lignin cellulose

Combining wood matrix with thermosetting resin promises to be a new generation of resin-based friction material alternatives. Herein, regenerated lignin-cellulose (RLC) was prepared by waste wood, and precursor matrix slurry (EP@RLC) was obtained by mixing aqueous epoxy resin (EP) with RLC in different proportions. The impregnation and low-temperature curing processes were used to realize the combination of carbon fibers (CFs) and wood-plastic matrix. RLC filled the voids between CFs and adhered to their surfaces to build a CF-RLC reinforced structure, improving the surface roughness of the CFs/wood-plastic resin-based composite (CFs/EP@RLC) and enhancing the tensile strength and wear resistance. It has excellent mechanical strength with the tensile strength of up to 151.9 MPa, tensile modulus of up to 8.52 GPa, and toughness of up to 9.05 MJ/m3. In the tribological performance test, CFs/EP@RLC showed a stable friction coefficient (0.06) and low wear rate (0.64 mm), and no damage occurred at the interface of CFs after a long period of cyclic testing. In comparison with current research on resin-based friction materials, the CFs/EP@RLC meet the requirements in terms of mechanical and tribological properties. Besides, the CFs contained in end-of-life products can be easily recovered in hot alkaline solutions.

The Roles of the Fluorescent In Situ Hybridization (FISH) and Comparative Genomic Hybridization (CGH) Techniques in the Detection of the Breast Cancer

This paper aimed to understand and compare the two popular cytogenetic techniques of fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH) in detecting breast cancer chromosomal abnormality. Several chromosomal anomalies play a role in the development of breast cancer, and the two above approaches play an important role in confirming fluorescence in situ hybridization in particular (FISH). However, comparative genomic hybridization has developed DNA copy number profiles for most of the publicly available breast cancer cell lines for the FISH methods rely on the fluorescent probes. Chromosomal profiles can be generated for the suspected chromosomal abnormality, copy number changes between the tumour and the DNA control can be compared, and the results can be registered. Today, modern cytogenetic tools such as fluorescence in situ hybridization (FISH) are more commonly used to detect any microdeletion that cannot be detected by conventional cytogenetic karyotypes that involve a high rate of cell division and good chromosomal morphology, which pose challenges for cytogeneticists, and a long period of testing and research. Usually, this is a problem for physicians, and there are still many drawbacks and disadvantages concerning the high benefits, such as false findings. Normal chromosome in situ hybridization requires the hybridization of a labelled DNA probe into denatured chromosomal DNA present in metaphase chromosomes in an air-dried microscope slide preparation. Metaphase spreads are used for traditional chromosome FISH (metaphase FISH). Positive and positive signs of hybridization also appear as a double spot, corresponding to the hybridized probe for both sister chromatids. A further extension of chromosome painting is comparative genomic hybridization (CCI-I). CCH involves simultaneous chromosome painting in two different colours using complete DNA from two similar sources as probes, which reveal variations concerning the benefit or loss of sub-chromosomal regions or even entire chromosomes.

ПРОБЛЕМЫ УПРАВЛЕНИЯ И КОММУНИКАЦИЙ В БИОТЕХНОЛОГИЧЕСКИХ СТАРТАПАХ

The purpose of the article is to identify management and communication challenges which a biotech startup faces at different stages of its development. Challenges connected with business idea creating and development are the most essential but they are difficult to be solved as their solution sometimes needs to change totally the whole startup. Management and communication challenges are less harmful and they can be resolved. So general managers should identify them and implement tools for their illumination. The general challenges of biotech sphere also affect startups. The long period of commercialization and payback of biotechnological innovations, their narrow focus, the low percentage of attracting venture investments at the early stages of the project, the limited financial instruments in the process of raising funds can deepen other problems of startups. The authors distinguish communication and management problems of biotech startups erased at internal and external level of a business. Nepotism, centralized authority, poor communication with investors, customers and legal state bodies are considered to be the main communication challenges. Poor organizational management, difficulties with operational finance management during long period of laboratory testing, poor management of uncertainty, difficulties with HR management are identified to be referred to management challenges.The authors’ proposals to described problems of biotech startups are assumed in the article.

A Novel Trading Strategy Framework Based on Reinforcement Deep Learning for Financial Market Predictions

The prediction of stocks is complicated by the dynamic, complex, and chaotic environment of the stock market. Investors put their money into the financial market, hoping to maximize profits by understanding market trends and designing trading strategies at the entry and exit points. Most studies propose machine learning models to predict stock prices. However, constructing trading strategies is helpful for traders to avoid making mistakes and losing money. We propose an automatic trading framework using LSTM combined with deep Q-learning to determine the trading signal and the size of the trading position. This is more sophisticated than traditional price prediction models. This study used price data from the Taiwan stock market, including daily opening price, closing price, highest price, lowest price, and trading volume. The profitability of the system was evaluated using a combination of different states of different stocks. The profitability of the proposed system was positive after a long period of testing, which means that the system performed well in predicting the rise and fall of stocks.

Evaluating the Ready Biodegradability of Biodegradable Plastics.

Reducing the environmental burden and assessing the safety of plastics are huge global challenges. However, standard test data on the ready biodegradability of plastics are limited. We evaluated the ready biodegradability of 8 biodegradable plastics using Organisation for Economic Co-operation and Development (OECD) test guideline 301F with nonspecific bacteria and examined the effects of prolonging the test duration to a maximum of 90 d. Cellulose used as a potential reference material for plastics was not comparable to the reference material of OECD test guideline 301, but it may be improved by using a test concentration lower than the typical test concentration (100 mg/L). Of the 8 plastics examined, polyamide 4, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), polycaprolactone, and poly(butylene succinate adipate; PBSA) were biodegraded by >60% by day 28 and considered to show ready biodegradability. Poly(3-hydroxybutyrate; PHB), poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid; PHBV), and poly(butylene succinate; PBS) were biodegraded but did not fulfill the ready biodegradability criteria. Because the typical test concentration is considered to have negative effects on biodegradation and calculation of biodegradation percentage, using a lower concentration may result in PHB, PHBV, and PBS fulfilling the ready biodegradability criteria. Poly(d,l-lactide; PLA) was not biodegraded. The biodegradation of PBS and PBSA was noted to vary depending on the used inoculum and/or particle size. For the 7 plastics except PLA, the percentage biodegradation on day 60 was larger than that on day 28, indicating that a longer test period could be useful for evaluating the environmental persistence of plastics. In tests in which the plastics were not biodegraded by day 60, no marked biodegradation was observed by day 90. Environ Toxicol Chem 2021;40:2443-2449. © 2021 SETAC.

Accommodative Exercises to Lower Intraocular Pressure.

Purpose This study investigated how a conscious change in ocular accommodation affects intraocular pressure (IOP) and ocular biometrics in healthy adult volunteers of different ages. Methods Thirty-five healthy volunteers without ocular disease or past ocular surgery, and with refractive error between −3.50 and +2.50 diopters, were stratified into 20, 40, and 60 year old (y.o.) age groups. Baseline measurements of central cornea thickness, anterior chamber depth, anterior chamber angle, cornea diameter, pupil size, and ciliary muscle thickness were made by autorefraction and optical coherence tomography (OCT), while IOP was measured by pneumotonometry. Each subject's right eye focused on a target 40 cm away. Three different tests were performed in random order: (1) 10 minutes of nonaccommodation (gazing at the target through lenses that allowed clear vision without accommodating), (2) 10 minutes of accommodation (addition of a minus 3 diopter lens), and (3) 10 minutes of alternating between accommodation and nonaccommodation (1-minute intervals). IOP was measured immediately after each test. A 20-minute rest period was provided between tests. Data from 31 subjects were included in the study. ANOVA and paired t-tests were used for statistical analyses. Results Following alternating accommodation, IOP decreased by 0.7 mmHg in the right eye when all age groups were combined (p = 0.029). Accommodation or nonaccommodation alone did not decrease IOP. Compared to the 20 y.o. group, the 60 y.o. group had a thicker ciliary muscle within 75 μm of the scleral spur, a thinner ciliary muscle at 125–300 μm from the scleral spur, narrower anterior chamber angles, shallower anterior chambers, and smaller pupils during accommodation and nonaccommodation (p's < 0.01). Conclusion Alternating accommodation, but not constant accommodation, significantly decreased IOP. This effect was not lost with aging despite physical changes to the aging eye. A greater accommodative workload and/or longer test period may improve the effect.

Impedance spectroscopy study of anticorrosive properties of epoxy compositions

Although metals and their alloys are important structural materials, electrochemical or chemical interactions between metal structures and the environment leads to their spontaneous destruction. In order to protect metal products from corrosion, epoxy resins and polymer composite materials can be applied. However, polymer-coated metals may degrade under operating conditions due to electrochemical reactions at the polymer-metal interface caused by water absorption and diffusion in epoxy coatings. The present study is aimed at an investigation of the anticorrosive behaviour characteristic of epoxy compositions following exposure to sulphuric acid. The method of impedance spectroscopy was applied to evaluate epoxy coatings on a steel base. The composition of the epoxy binder included bisphenol A resins cured with various amine curing agents. In order to identify structural changes in materials, as well as the changes in their protective properties, the effects of an aggressive environment were simulated by means of exposure to concentrated sulphuric acid over a 30-day period. Impedance hodographs of the studied systems were obtained and equivalent schemes for the approximation of experimental data proposed. The high porosity of the NPEK-114L based epoxy system was established to result in an increase in the corrosion rate. Dissolution of corrosion products over a longer test period – and consequent higher diffusion of corrosive ions in the coating – was determined to cause a decrease in corrosion resistance. Epoxy compositions based on NPEL-128 resin (oligomeric product based on diphenylolpropane diglycidyl ether) demonstrated improved anticorrosion characteristics. The addition of alkyl glycidyl ether for NPEK-114L resin viscosity reduction was shown to affect the protective properties of the composite under acid exposure.

ON THE MOVEMENT OF SCIENTIFIC THOUGHT CONCERNING STATUSES IN CIVIL LAW

Abstract: the foundations of the legal facts doctrine were laid in the prerevolutionary period. At that time the first scientific ideas regarding the systematization and typification of legal facts were formed and hypotheses were put forward. Being perceived by soviet scientists, the theory of legal facts received a point, but a significant addition and some completion in the works of prominent representatives of the soviet civil law science. The objectively justified conservatism of this doctrine leads to the fact that new trends of factual reality find their scientifically justified place in the system of legal facts only after a long period of scientific testing. This situation has developed in relation to statuses in civil law. Being noticed in the framework of the legal facts theory in the pre-revolutionary period, these phenomena have not earned their strictly defined place in the system of legal facts and in the system of law as a whole. The reason for this is the multi-aspect (diversity) of the concept "status". The role of legal statuses not only in the movement of civil legal relations, but also in the legal system as a whole is still the subject of scientific discussion. How this scientific discussion developed in the pre-revolutionary, soviet and modern period is reflected in this article with the proposal of the vision of the role of statuses in civil law.

The Role of Every-Day Cosmetics in Altering the Skin Microbiome: A Study Using Biodiversity

As described in previous work, the use of synthetic chemical ingredients in modern cosmetics is postulated to be a cause of damage to the skin microbiome. The discovery that biodiversity on the human skin is currently the only reliable indicator of skin health, meant that for the first time, a mechanism to test for healthy skin was possible. Using this mechanism and in collaboration with The Medical University of Graz, who carried out the independent study, this work aimed to help answer whether modern day synthetic cosmetics are a main cause of long-term damage to the skin microbiome. Thirty-two human participants tested three different face washes for their effect on the skin’s microbial diversity, along with skin pH, moisture and TEWL (trans-epidermal water loss), washing twice-a-day for four weeks. The upper volar forearm of the volunteers was swabbed at the beginning, two weeks in and at the end of the four weeks. 16S rRNA sequencing was used. One leading ‘natural’ brand full of synthetic ingredients, a leading synthetic brand and a 100% natural face wash were used. Results give the first indications of a link between synthetic ingredients in a cosmetics product and its effect on skin microbiome biodiversity. It paves the way for future studies on the topic with a larger sample group, longer test period and standardised methodology to create a universal standard for testing the health of skin using benchmark diversity values. This can be used in the future to test the effectiveness of cosmetics or ingredients on skin health, leading to the restriction in cosmetics of products proven to harm the skin’s natural environment.

A Maieutic Exploration of Nudging Strategies for Regional Climate Applications Using the WRF Model.

The use of nudging in the Weather Research and Forecasting (WRF) Model to constrain regional climate downscaling simulations is gaining in popularity because it can reduce error and improve consistency with the driving data. While some attention has been paid to whether nudging is beneficial for downscaling, very little research has been performed to determine best practices. In fact, many published papers use the default nudging configuration (which was designed for numerical weather prediction), follow practices used by colleagues, or adapt methods developed for other regional climate models. Here, a suite of 45 three-year simulations is conducted with WRF over the continental United States to systematically and comprehensively examine a variety of nudging strategies. The simulations here use a longer test period than did previously published works to better evaluate the robustness of each strategy through all four seasons, through multiple years, and across nine regions of the United States. The analysis focuses on the evaluation of 2-m temperature and precipitation, which are two of the most commonly required downscaled output fields for air quality, health, and ecosystems applications. Several specific recommendations are provided to effectively use nudging in WRF for regional climate applications. In particular, spectral nudging is preferred over analysis nudging. Spectral nudging performs best in WRF when it is used toward wind above the planetary boundary layer (through the stratosphere) and temperature and moisture only within the free troposphere. Furthermore, the nudging toward moisture is very sensitive to the nudging coefficient, and the default nudging coefficient in WRF is too high to be used effectively for moisture.

Duration of life-cycle toxicity tests with the ostracod Heterocypris incongruens.

An acute sediment toxicity test using the ostracod Heterocypris incongruens is user friendly and has high sensitivity; however, a life-cycle test using this species has not been developed. The most challenging problem when developing a life-cycle test is that the egg development time varies greatly and is sometimes too long (> 150 d) to monitor. It is desirable to shorten the duration of life-cycle toxicity tests including the observation period of egg development while preserving the ecological relevance of the net reproductive rate (R0 ), an endpoint in the life-cycle test. Therefore, in the present study, we suggest a practical test duration for R0 using population growth rate (λ) as a measure of ecological relevance. We collected a range of life history characteristics of the ostracod by combining data from the literature and experimental results, constructed population matrix models, and calculated λ for 20 life history patterns. The results showed that a longer test period (> 150 d) did not increase the correlation coefficients between R0 and λ. Rather, a shorter test duration resulted in R0 being highly correlated with λ. Our results suggest that a life-cycle toxicity test using the ostracod can provide an ecologically relevant toxicity endpoint, even if the test is abandoned after approximately 50 d and unhatched eggs remain. Environ Toxicol Chem 2017;36:3443-3449. © 2017 SETAC.

First report of the establishment of the biocontrol agent Trichilogaster acaciaelongifoliae for control of invasive Acacia longifolia in Portugal

Acacia longifolia is one of the most widespread invasive plants in coastal areas of Portugal, where it disrupts the composition and function of natural plant and insect communities as well as microorganisms in the soil. The Australian bud‐galling wasp, Trichilogaster acaciaelongifoliae, induces a reduction in seed production of A. longifolia and has been successfully used as a biological control agent in South Africa for more than 30 years. After a long period of host specificity testing and risk assessment, release permits were issued by national and European Union authorities and, in late 2015, T. acaciaelongifoliae was released into eight selected sites along the Portuguese coast. During April–July 2016, post‐release monitoring detected 56 galls at four of the release sites. At two of the sites second‐generation galls were noted in January 2017, but it is still too soon to measure their abundance. Despite the inherent difficulties associated with transferring the insects between hemispheres, T. acaciaelongifoliae successfully completed its life cycle in Portugal in the wild, and is seemingly starting to proliferate. Further releases were made in late 2016 and monitoring of the insects will continue.

Practice effect in Symbol Digit Modalities Test in multiple sclerosis patients treated with natalizumab

ObjectivesHow practice effect influences cognitive testing measured by monthly Symbol Digit Modalities Test (SDMT) during natalizumab treatment, and what factors confound such effect. MethodsEighty patients were examined monthly with SDMT for 26.2±8.4 months. After 26.0±8.1 months, SDMT was also performed with a rearranged key in 59 cases. Results of SDMTs with the rearranged and previous regular key were compared. We examined if gender, age, Extended Disability Status Scale (EDSS), relapses, and disability progression/improvement influence SDMT performed with the regular and the rearranged key, respectively. We also explored if natalizumab applied before regular monthly SDMT may influence practice effect and cognition. ResultsSDMT performance improved by 1.2 points/test during the first six months and by 0.4 points/test thereafter. Rearranging the symbols of the key after 26.0±8.1 months returned SDMT scores to baseline indicating a practice effect. Such practice effect was more significant after longer testing period, but was not influenced by gender, age, relapses, disability progression and prior natalizumab treatment. Although the change from baseline to 2.5 years was significant in subgroups with EDSS 0–3, 3.5–5.5 and 6–7.5, this was higher in patients with EDSS 0–3 compared to 6–7.5. ConclusionsPractice effect significantly contributes to continuous improvement in SDMT performance during natalizumab treatment: to test cognition, a change in key is required. Practice effect is less pronounced in patients with advanced disease. Cognition remains stable even in patients with progressive disease during more than 2 years of natalizumab treatment indicated by scores corresponding to baseline after changing the key.

Matrix deposition on cell-seeded polymeric enthesis repair scaffolds under mechanostimulation

Event Abstract Back to Event Matrix deposition on cell-seeded polymeric enthesis repair scaffolds under mechanostimulation Jonathan Tapp1, Mamadou Diallo1, Christopher Alexander1, Joel D. Bumgardner1, Warren Haggard1 and Jessica A. Jennings1 1 University of Memphis, Biomedical Engineering Department, United States Introduction: The incidence of tendon injury is growing; as a result so is the demand for tendon repair strategies[1]. Synthetic polymer fabrics are implemented in tendon repair due to similar mechanical strength properties to a human tendon. The ultimate goal is to improve biocompatibility of artificial tendons. Polymer fabric strips were housed in a custom built bioreactor, seeded with fibroblast and osteoblast cells, and subject to mechanostimulation. The primary objective is to analyze matrix deposition of cell-seeded polymer fabric scaffolds, with and without an applied strain. Methods: The modification of a bioreactor provided controlled, cyclical patterns of strain (Fig 1)[2]. 150x22 mm polyethylene (PET) fabric scaffolds were sterilized by immersion in 2% bleach solution, ultrapure water, and 70% ethanol, followed by thorough rinsing with ultrapure water. The fabric scaffolds were submerged in Dulbecco’s modified eagle media (DMEM) containing 10% fetal bovine serum (FBS) and 100 µg/ml Normocin antibiotic. MC3T3 pre-osteoblast and NIH3T3 fibroblast cells were seeded at a density of 3x 105 cells/mL on separate regions of the scaffold. Once the PET cell scaffolds were secured in the bioreactor, a 5% strain was applied to the region containing fibroblasts for 5 hours daily. The MC3T3 region was kept static. Unstrained scaffolds in petri-dish conditions and bioreactor conditions with media circulation were included as control groups in the 7-day study. Cell DNA growth was quantified via a Picogreen assay, collagen content via a Sirius red collagen detection assay, and glycosaminoglycan (GAG) content via an Alcian blue assay. The amounts of collagen and GAG were normalized using the ratios of matrix component to DNA. Statistical differences between groups were detected using a one-way ANOVA with Holm-Sidak post-test at a confidence level a=0.05. Results: The fibroblast regions of the scaffolds exposed to daily stretching had a higher GAG to DNA ratio than the scaffolds that were only exposed to fluid flow and the control group (Fig 2). Collagen formation was significantly higher on the unstrained scaffolds within the bioreactor with media flow. (Fig 3). Discussion: GAG, a reliable indicator of tendon extracellular matrix (ECM), was deposited in greater amounts when cells were subject to strain. The collagen production of the scaffolds under periodic strain compared to no strain was lower than expected. A possible reason is the static scaffolds were assessed at a point when the cells were in a proliferative phase and producing collagenous matrix at a higher rate. Studies with longer test periods are ongoing to more accurately model the matrix deposition over time, as well as efficacy of cell-seeded ECM-conditioned scaffolds in promoting functional tendon and enthesis repair. Conclusions: The combination of cell seeding with polymer fabrics could lead to improved therapies for tissue repair with minimal inflammation. Parwinder Singh; Jared Cooper; Lauren Eichaker

Calculating value: a digital library’s social media campaign

Purpose – The purpose of this paper is to discuss a social media campaign used to promote a digital library of archival resources. Design/methodology/approach – Librarians planned and executed a social media campaign using Tumblr and Pinterest and consulted Google Analytics and database reports to determine the impact. Findings – The campaign resulted in few conversions back to the digital library and little return on investment. Research limitations/implications – The campaign has been in effect for only five months, a longer testing period may be needed. Also, additional social media platforms will be added to the test. Originality/value – This is one of few examples of return on investment applied to social media and digital library promotion.

The Validity and Reliability of Co-heating Tests Made on Highly Insulated Dwellings

The ability of a co-heating test to accurately identify a dwelling's envelope heat-loss coefficient has been explored using dynamic thermal simulation techniques, against a number of fabric specifications ranging from 1990 UK regulation levels through to modern Passivhaus requirements.Simple analysis methods can underestimate the heat-loss coefficient, by up to 50% for the highest performance standards considered. Using the best test and analysis methods found the envelope heat loss coefficient could be determined for current stock to better than 10% accuracy in a three week test duration. However that accuracy could not be reliably achieved in a shorter period, nor could it be achieved with a dwelling specification representing emerging standards of insulation, unless longer test periods were used.

The Vestibular Effects of Repeated Low-Level Blasts.

The objective of this study was to use a prospective cohort of United States Marine Corps (USMC) instructors to identify any acute or long-term vestibular dysfunction following repeated blast exposures during explosive breaching training. They were assessed in clinic and on location during training at the USMC Methods of Entry School, Quantico, VA. Subjects received comprehensive baseline vestibular assessments and these were repeated in order to identify longitudinal changes. They also received shorter assessments immediately following blast exposure in order to identify acute findings. The main outcome measures were the Neurobehavioral Symptom Inventory, vestibular Visual Analog Scale (VAS) of subjective vestibular function, videonystagmography (VNG), vestibular evoked myogenic potentials (VEMP), rotary chair (including the unilateral centrifugation test), computerized dynamic posturography, and computerized dynamic visual acuity. A total of 11 breachers and 4 engineers were followed for up to 17 months. No acute effects or longitudinal deteriorations were identified, but there were some interesting baseline group differences. Upbeat positional nystagmus was common, and correlated (p<0.005) with a history of mild traumatic brain injury (mTBI). Several instructors had abnormally short low-frequency phase leads on rotary chair testing. This study evaluated breaching instructors over a longer test period than any other study, and the results suggest that this population appears to be safe from a vestibular standpoint at the current exposure levels. Upbeat positional nystagmus correlated with a history of mTBI in this population, and this has not been described elsewhere. The data trends also suggest that this nystagmus could be an acute blast effect. However, the reasons for the abnormally short phase leads seen in rotary chair testing are unclear at this time. Further investigation seems warranted.

Mathematical Model Research of Intelligent Rapid Testing System for Textile Materials Moisture Regain

Because there exist some disadvantages of the traditional moisture regain testing method (oven drying) for textile materials, such as longer testing period, higher energy wastage, laboring intensity, and inefficient, a new instrument i.e. moisture regain rapid testing system has been researched, designed and manufactured for raw silk in this project. This system can record real-time the weight of raw silk sample during the drying in the certain environment oven. The index prediction model has been developed based on the accumulating generation operator (1-AGO) after the data have been pretreated. According to this model, the percent of error is only 2.09% between the predicted value and actual result of raw silk moisture regain within the drying cycle of 40min by the rapid testing system.

Determination of groundwater flow direction in thermal response test analysis for geothermal heat pump systems

A methodology was proposed to determine the groundwater flow direction from a thermal response test analysis using three boreholes. The methodology was verified using sample test data generated from a three-dimensional numerical model for the borehole ground heat exchangers. It was found that the groundwater flow velocity and the borehole separation had significant effects on the correctness of the estimated groundwater flow direction. A smaller borehole separation and a higher groundwater flow helped improve the traveling speed of the heat front and, consequently, the thermal interference effect from adjacent boreholes. This was crucial for the correct prediction of the groundwater flow direction in the analysis. The adoption of a longer test period also strengthened the borehole thermal interference and, hence, the accuracy of the estimated groundwater flow direction. Besides, the minimum groundwater flow velocity capable of being determined with confidence from the analysis could also be decreased. Finally, the use of an unequally spaced borefield could further enhance the effectiveness of the methodology.