Time-series modeling of moisture exposure on timber structures

This paper presents a methodology with the purpose of modeling and simulating outdoor temperature and relative humidity (vapor concentration) related to moisture exposure on timber structures. The methodology is based on time-series analysis with recorded meteorological data used as input. In situations where recorded data is missing or consists of limited sequences, this methodology offers the possibility to use synthetic data instead. It was found that temperature and vapor concentration could be modeled by a combination of deterministic functions and stochastic processes, which consider the dynamics of the climate, including slow seasonal variations and fast daily changes. Specifically, a model for temperature and vapor concentration in Stockholm, Sweden, is presented together with simulation results. It is shown that the model produces simulated sequences with statistical properties close to the real recorded ones.     

Binding, internalization, and degradation of antiproliferative heparan sulfate by human embryonic lung fibroblasts

Pretargeting methodologies can produce high tumor:blood ratios, but their role in cancer radioimmunotherapy (RAIT) is uncertain. A pretargeting method was developed using a streptavidin (StAv) conjugate of MN-14 IgG, an anti-carcinoembryonic antigen (CEA) murine monoclonal antibody (mab) as the primary targeting agent, an anti-idiotype antibody (WI2 IgG) as a clearing agent, and DTPA- or DOTA-conjugated biotin as the radiolabeled targeting agent. A variety of reagents and conditions were examined to optimize this method. At 3 h, 111In-DTPA-peptide-biotin tumor uptake was 3.9 +/- 0.8% per gram and tumor:blood ratios were > 11:1. By 24 h, this ratio was 178:1, but tumor accretion declined in accordance with the gradual loss of StAv-MN-14 from the tumor. Tissue retention was highest in the liver and kidneys, but their tumor:organ ratios were > 2:1. Dosimetry predicted that radiolabeled MN-14 alone would deliver higher tumor doses than this pretargeting method. Increasing the specific activity and using DOTA-biotin in place of DTPA increased tumor uptake nearly 2-fold, but analysis of StAv-MN-14's biotin-binding capacity indicated over 90% of the initial biotin-binding sites were blocked within 24 h. Animals fed a biotin-deficient diet had 2-fold higher 111In-DOTA-biotin uptake in the tumor, but higher uptake also was observed in all normal tissues. Although exceptionally adept at achieving high tumor:blood ratios rapidly, the tumor uptake of radiolabeled biotin with this pretargeting method is significantly (p < 0.0001) lower than that with a radiolabeled antibody. Endogenous biotin and enhanced liver and kidney uptake may limit the application of this method to RAIT, especially when evaluating the method in animals, but with strategies to overcome these limitations, this pretargeting method could be an effective therapeutic alternative.     

Environmental considerations in the Swedish building and construction industry: the role of costs,institutional setting,and information

Despite increasing evidence that being an environment-friendly company not only benefits the environment but also makes long-term economic sense, the transition to a more sustainable society is extremely slow. This is true of the building and construction industry as well. At a strategic level, environmental issues have received more attention with the establishment of roles such as environmental managers and implementation of advanced environmental management systems. However, adoption has been slow in the absence of a holistic approach to environmental challenges, partly reinforced by a perception that giving more than the legally required level of environmental consideration will only add to costs without corresponding financial benefits. This raises the following question that the study aims to answer: What is the most important factor influencing decision makers’ in adopting environmental considerations? To this end, it analysed questionnaire data collected from decision makers in the Swedish construction industry along with an in-depth case study of a specific building and construction company. The results show that decision makers perceive informational and institutional constraints on the adoption of environmental considerations. Lack of information is perceived as the biggest obstacle to environmental considerations. If information and knowledge about clients’ and end users’ financial benefits from adopting environmental considerations need to be exploited, they have to be supported by contractual forms that discard a short-term focus on the investment costs of a building in favour of a focus on long-term operational and maintenance costs and benefits.     

Indoor climate in low-energy houses—an interdisciplinary investigation

If energy demand in the building sector should be decreased, low-energy buildings, which are built with the aim of decreasing the use of energy, but still provide a good environment for the occupants, ought to be built on a larger scale. Investigations into how experimental houses function provides the opportunity of improving next-generation houses. This paper presents the results of an interdisciplinary investigation of the thermal environment and the space heating in 20 low-energy terraced houses. Qualitative interviews with the occupants as well as measurements of physical parameters have been conducted for this purpose. When the houses are inhabited and household appliances and candles are being used, the temperature can be managed within acceptable limits, even on cold days. However, those living in middle houses are generally more satisfied with their indoor temperature than the households of the gable houses. Results from both interviews and measurements show that there is a temperature difference between the floor levels, which is more pronounced in the gable houses. One outcome of the investigation is that information about the functionality of the heating system given to the households should be improved. Another outcome is that the accuracy of the temperature regulation system could be better.     

GIS supported calculations of (137)Cs deposition in Sweden based on precipitation data

It is of interest to know the spatial variation and the amount of (137)Cs e.g. in case of an accident with a radioactive discharge. In this study, the spatial distribution of the quarterly (137)Cs deposition over Sweden due to nuclear weapons fallout (NWF) during the period 1962-1966 was determined by relating the measured deposition density at a reference site to the amount of precipitation. Measured quarterly values of (137)Cs deposition density per unit precipitation at three reference sites and quarterly precipitation at 62 weather stations distributed over Sweden were used in the calculations. The reference sites were assumed to represent areas with different quarterly mean precipitation. The extent of these areas was determined from the distribution of the mean measured precipitation between 1961 and 1990 and varied according to seasonal variations in the mean precipitation pattern. Deposition maps were created by interpolation within a geographical information system (GIS). Both integrated (total) and cumulative (decay corrected) deposition densities were calculated. The lowest levels of NWF (137)Cs deposition density were noted in north-eastern and eastern parts of Sweden and the highest levels in the western parts of Sweden. Furthermore the deposition density of (137)Cs, resulting from the Chernobyl accident was determined for an area in western Sweden based on precipitation data. The highest levels of Chernobyl (137)Cs in western Sweden were found in the western parts of the area along the coast and the lowest in the east. The sum of the deposition densities from NWF and Chernobyl in western Sweden was then compared to the total activity measured in soil samples at 27 locations. Comparisons between the predicted values of this study show a good agreement with measured values and other studies.     

Analysis on the control principle of the active DC filter in theLindome converter station of the Konti-Skan HVDC link

The control principle of a hybrid passive-active DC filter installed in the Lindome HVDC converter station is analyzed in this paper. The controller of the active filter includes two basic functions: an integrator and a compensator. The main advantage of the Lindome controller is its simple structure for implementation in a digital signal processor (DSP). The drawbacks of this controller are its long response time, low stability margin and the filtering of an unnecessary number of frequencies. An alternative control strategy using a number of notch filters has been investigated. The notch filters can be tuned to those frequencies that need to be damped. This controller gives a much shorter system response time and improved stability margin     

Determination of endpoint temperatures in previously heat treated beef using reflectance spectroscopy

Heat processing endpoint temperature affects several quality parameters of meat. The present paper focuses on using near-infrared and visual light reflectance spectroscopy at 400-2500 nm to determine the endpoint temperature in previously heated ground beef. Glass fibre filters with beef juice centrifuged from m. longissimus lumborum were used as samples for the technique Dry Extract Spectroscopy by Infrared Reflection (DESIR). Combined with multivariate analysis, this method gave prediction errors down to ± 0.74 °C in the temperature range 65.6-75.6 °C, showing that DESIR is a potential screening method. The dominant part of the predictive information was in the visual part of the spectra.     

Improved early bone-implant integration in transgenic mice overexpressing bovine growth hormone

Titanium implants were inserted in transgenic mice overexpressing bovine growth hormone. Four weeks after insertion the implants were cut out en bloc with the surrounding bone. The undecalcified specimens were cut and ground to a thickness of approximately 10 m. Histomorphometry demonstrated significantly more direct bone to metal contact for the transgenic mice than for the non-transgenic littermates. The results indicate that endogenous high levels of bovine growth hormone result in improved early bone-implant integration. This study indicate that it may be possible to systemically administrate growth hormone in man, in the early healing in phase, to improve implant integration.     

Design and performance of mid-ranging controllers

Mid-ranging control applications are multivariate and often involve input constraints. Although some strategies have been reported to work well in industry, no systematic comparison has ever been made. The purpose of this report is to compare these schemes to a model-based predictive control (MPC) approach designed specifically for constrained multivariable control problems. The results indicate that although there are special cases where the existing schemes work reasonably well, MPC is best able to solve the problem in the general case.