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Pipeline break detection using pressure transient monitoring

Sudden pipe breaks occur in water transmission pipelines and distribution mains. The consequences of these breaks can be very expensive because of the service interruption, the cost of repair, and damage to surrounding property and infrastructure. The costs associated with the pipeline breaks can be reduced by minimizing the break detection and location time. This paper presents a new continuous m

Recovery of soil pH, cation-exchange capacity and the saturation of exchange sites from stemflow-induced soil acidification in three Swedish beech (Fagus sylvatica L.) forests

Stemflow water acidifies the soil in beech stands impacted by atmospheric deposition. To investigate whether the soil recovers from acidification, stemflow was experimentally removed. A horizon material was sampled at a distance of 10-250 cm From the stems. Before the onset of the experiment, there were stemflow-induced gradients in the saturation of exchange sites with K+, H+ and Na+ that were la

Energy-based throughput analysis of packet radio networks

The increasing use of wireless technology utilizing unlicensed frequency bands calls for more in-depth analysis of interference and coexistence between systems. In this paper a framework is presented for detailed analysis of the performance of coexisting networks in shared frequency bands. The framework allows for multiple packet lengths to be used by the communicating devices and the analysis is

Introduktion till fuktmekaniken (informationsskrift i serien: Fuktsäkerhet i byggnader)

Varje år drabbas många byggnader av fuktskador. Mer än 80 procent av alla byggskador anses vara orsakade av fukt på ett eller annat sätt. Orsaken till många fuktproblem är ofta brist på kunskap om vissa grundläggande fuktmekanismer. Syftet med denna skrift är att ge läsaren de grundläggande kunskaperna och att ge förståelse och känsla för olika fenomen inom fuktmekaniken, så att man kan delta i f

Transplantation of full-thickness retina in the normal porcine eye: surgical and morphologic aspects.

PURPOSE: To report a surgical technique for transplantation of full-thickness neuroretinal sheets into the subretinal space of a large animal with a vascularized retina and to establish the light microscopic morphology of such specimens. METHODS: Twelve normal pigs underwent transplantation of a neuroretinal sheet from a neonatal donor into the subretinal space by means of a vitrectomy-based techn

Soil microbial community structure in relation to vegetation management on former agricultural land

Agricultural overproduction has led the European Union to encourage long-term abandonment of agricultural land. To enhance the transition of agricultural land to natural grasslands or forests different management practices in relation to vegetation can be used. The aim of this study was to understand the interactions between plant and associated soil microbial communities during the succession of

Stories of Achievements - Narrative Features of Organizational Performance

Stories of achievements is a study concerning uses of the notion of organizational performance. It shows the variety of meanings given the notion in dictionaries, management literature, sports, and performance indicators; it also explores how such meanings are constructed and how they are attached to this notion in new contexts, such as in the activity reports of public libraries. Examining uses

Attempts to probe the ozone layer and the ultraviolet-B levels of the past

To get a proper perspective on the current status of atmospheric ozone, which protects the biosphere from ultraviolet-B (UV-B; 280-315 nm) radiation, it would be of value to know how ozone and UV-13 radiation have varied in the past. The record of worldwide ozone monitoring goes back only a few decades, and the record of reliable UV-13 measurements is even shorter. Here we review indirect methods

Borreliosis as a cause of peripheral facial palsy: a multi-center study

Borreliosis is known to be a common cause of peripheral facial palsy in Stockholm and its vicinity. The aim of the present study was to investigate the frequency and characteristics of borreliosis among patients with peripheral facial palsy in different parts of Sweden. All serological tests were performed in one laboratory. Ten Swedish Ear Nose and Throat clinics participated in a prospective 1-y

Effects of estradiol and medroxyprogesterone acetate on morphology, proliferation and apoptosis of human breast tissue in organ cultures

Background: Human breast tissue undergoes phases of proliferation, differentiation and regression regulated by changes of the levels of circulating sex hormones during the menstrual cycle or aging. Ovarian hormones also likely play a key role in the etiology and biology of breast cancer. Reports concerning the proliferative effects of steroid hormones on the normal epithelium of human breast have

Cryogenic system of the MAX-Wiggler

A novel insertion device for electron storage rings called the MAX-Wiggler has been constructed and commissioned at MAX-lab. The MAX-Wiggler is a cold bore superconducting wiggler magnet with 47 3.5 T poles and a period length of 61 mm aimed for the production of X-rays at the 1.5 GeV electron storage ring MAX-II at MAX-lab. This note describes the cryogenic system of the MAX-Wiggler, theoretical

Polymorphisms at the ABO locus in subgroup A individuals

BACKGROUND: The common ABO allele sequences are known, but little or no genetic information is available on the rare but important A subgroups. STUDY DESIGN AND METHODS: Blood group ABO polymorphism was analyzed in genomic DNA from 45 rare subgroup A individuals by sequence-specific primer polymerase chain reaction and amplified fragment length polymorphism investigating exons VI and VII in the AB

The Back-scattering Problem in Three Dimensions

In this thesis we study the (inverse) back-scattering problem for the Schr"odinger operator in $R^3$. We introduce the back-scattering transform $B(v)$ of a real-valued potential $vin C_0^infty(R^3)$, and prove that the back-scattering data associated to $v$ determine $B(v)$. Under the assumption that the Schr"odinger operator $H_v=-Delta +v$ has no eigenvectors in $L^2(R^3)$ it is shown that $B(v