Risk minimization in water quality control problems of a river system

Methodologies are presented for minimization of risk in a river water quality management problem. A risk minimization model is developed to minimize the risk of low water quality along a river in the face of conflict among various stake holders. The model consists of three parts: a water quality simulation model, a risk evaluation model with uncertainty analysis and an optimization model. Sensitivity analysis, First Order Reliability Analysis (FORA) and Monte-Carlo simulations are performed to evaluate the fuzzy risk of low water quality. Fuzzy multiobjective programming is used to formulate the multiobjective model. Probabilistic Global Search Laussane (PGSL), a global search algorithm developed recently, is used for solving the resulting non-linear optimization problem. The algorithm is based on the assumption that better sets of points are more likely to be found in the neighborhood of good sets of points, therefore intensifying the search in the regions that contain good solutions. Another model is developed for risk minimization, which deals with only the moments of the generated probability density functions of the water quality indicators. Suitable skewness values of water quality indicators, which lead to low fuzzy risk are identified. Results of the models are compared with the results of a deterministic fuzzy waste load allocation model (FWLAM), when methodologies are applied to the case study of Tunga-Bhadra river system in southern India, with a steady state BOD-DO model. The fractional removal levels resulting from the risk minimization model are slightly higher, but result in a significant reduction in risk of low water quality. (c) 2005 Elsevier Ltd. All rights reserved.

Integration-free algorithms for fixed end-point regulator problems

A new formulation is suggested for the fixed end-point regulator problem, which, in conjunction with the recently developed integration-free algorithms, provides an efficient means of obtaining numerical solutions to such problems.

Efficient algorithms for domination and Hamilton circuit problems on permutation graphs

The domination and Hamilton circuit problems are of interest both in algorithm design and complexity theory. The domination problem has applications in facility location and the Hamilton circuit problem has applications in routing problems in communications and operations research.The problem of deciding if G has a dominating set of cardinality at most k, and the problem of determining if G has a Hamilton circuit are NP-Complete. Polynomial time algorithms are, however, available for a large number of restricted classes. A motivation for the study of these algorithms is that they not only give insight into the characterization of these classes but also require a variety of algorithmic techniques and data structures. So the search for efficient algorithms, for these problems in many classes still continues.A class of perfect graphs which is practically important and mathematically interesting is the class of permutation graphs. The domination problem is polynomial time solvable on permutation graphs. Algorithms that are already available are of time complexity O(n2) or more, and space complexity O(n2) on these graphs. The Hamilton circuit problem is open for this class.We present a simple O(n) time and O(n) space algorithm for the domination problem on permutation graphs. Unlike the existing algorithms, we use the concept of geometric representation of permutation graphs. Further, exploiting this geometric notion, we develop an O(n2) time and O(n) space algorithm for the Hamilton circuit problem.

”Waxaa i bartay hooyaday waawa u muhiim naaska caruurta.” Äitini opetti, että rintamaito on tärkeää lapselle. Osallistava tutkimus auktoritatiivisen tiedon omaksumisesta somalikulttuuritaustaisten naisten imetyskäytännöissä.

Suomessa asuvat somalitaustaiset maahanmuuttajaäidit luopuvat imetyksestä ja ruokkivat vauvojaan äidinmaidonkorvikkeella, vaikka somalikulttuurissa arvostetaan imetystä. Tuen ja tiedon puutetta on arveltu syyksi pulloruokinnan yleisyyteen. Tarkoituksenani on tutkia osallistavia menetelmiä käyttäen, minkälaisia imetykseen liittyviä tietojärjestelmiä somaliäidit pitävät auktoritatiivisina eli arvovaltaisina. Tarkastelen tiedon auktoritatiivisuutta etnografisten esimerkkien valossa hyödyntäen Brigitte Jordanin auktoritatiivisen tiedon käsitettä. Tutkin Jean Pierre Olivier de Sardanin teorian avulla, kuinka paikalliset populaarit tietojärjestelmät kohtaavat tieteellis-teknisen tiedon kehityksen kontekstissa. Tutkin myös, kuinka somaliäitien imetystietojärjestelmät kohtaavat suomalaisen terveydenhoitojärjestelmän edustaman imetystiedon. Osallistavien menetelmien tarkoituksena on saada heikkojen ja sorrettujen yhteisöjen ääni kuuluviin. Tutkimukseni tiedonantajina on seitsemäntoista somalimaahanmuuttajaäitiä ja yksi suomalainen äitiys- ja lastenneuvolan terveydenhoitaja. Käytän tiedonkeruumenetelminä puolistrukturoituja teemahaastatteluja, jonka lisäksi teen osallistuvaa havainnointia ja osallistavia menetelmiä kolmessa ryhmähaastattelutilanteessa. Käytän Rapi Rurad Appraisal (RRA) –menetelmiä, kuten Venn-diagrammia ja pisteytystä. Tutkimukseni tulos on, että somaliäitien imetykseen liittyvä tieto koostuu kolmesta tietojärjestelmästä, joita ovat sukuverkostoista tuleva perinteinen tietotaito, islaminuskon terveystieto sekä suomalaisen terveydenhoitojärjestelmän tieto. Näistä eri tietolähteistä tuleva imetystieto ei ole sisällöltään ristiriidassa. Imetykseen liittyvät vaikeudet ovat käytännön ongelmiin, kuten sukuverkoston hajoamiseen ja suomalaisen terveydenhoitojärjestelmän kanssa kommunikointiin liittyviä.

Generating artificial chromosomes with probability control in genetic algorithm for machine scheduling problems

In this paper, a novel genetic algorithm is developed by generating artificial chromosomes with probability control to solve the machine scheduling problems. Generating artificial chromosomes for Genetic Algorithm (ACGA) is closely related to Evolutionary Algorithms Based on Probabilistic Models (EAPM). The artificial chromosomes are generated by a probability model that extracts the gene information from current population. ACGA is considered as a hybrid algorithm because both the conventional genetic operators and a probability model are integrated. The ACGA proposed in this paper, further employs the ``evaporation concept'' applied in Ant Colony Optimization (ACO) to solve the permutation flowshop problem. The ``evaporation concept'' is used to reduce the effect of past experience and to explore new alternative solutions. In this paper, we propose three different methods for the probability of evaporation. This probability of evaporation is applied as soon as a job is assigned to a position in the permutation flowshop problem. Experimental results show that our ACGA with the evaporation concept gives better performance than some algorithms in the literature.

Substance misuse problems during pregnancy with special emphasis on buprenorphine

Maternal drug abuse during pregnancy endangers the future health and wellbeing of the infant and growing child. On the other hand, via maternal abstinence, these problems would never occur; so the problems would be totally preventable. Buprenorphine is widely used in opioid maintenance treatment as a substitute medication. In Finland, during 2000 s buprenorphine misuse has steadily increased. In 2009 almost one third of clientele of substance treatment units were in treatment because of buprenorphine dependence. At Helsinki Women s Clinic the first child with prenatal buprenorphine exposure was born in 2001. During 1992-2001 in the three capital area maternity hospitals (Women s clinic, Maternity hospital, Jorvi hospital) 524 women were followed at special antenatal clinics due to substance abuse problems. Three control women were drawn from birth register to each case woman and matched for parity and same place and date of the index birth. According to register data mortality rate was 38-fold higher among cases than controls within 6-15 years after index birth. Especially, the risk for violent or accidental death was increased. The women with substance misuse problems had also elevated risk for viral hepatitis and psychiatric morbidity. They were more often reimbursed for psychopharmaceuticals. Disability pensions and rehabilitation allowances were more often granted to cases than controls. In total 626 children were born from these pregnancies. According to register data 38% of these children were placed in out-of-home care as part of child protection services by the age of two years, and half of them by the age of 12 years, the median follow-up time was 5.8 years. The risk for out-of-home care was associated with factors identifiable during the pre- and perinatal period. In 2002-2005 67 pregnant women with buprenorphine dependence were followed up at the Helsinki University Hospital, Department of Obstetrics and Gynecology. Their pregnancies were uneventful. The prematurity rate was similar and there were no more major anomalies compared to the national statistics. The neonates were lighter compared to the national statistics. They were also born in good condition, with no perinatal hypoxia as defined by standard clinical parameters or certain biochemical markers in the cord blood: erythropoietin, S100 and cardiac troponin-t. Almost 80% of newborns developed neonatal abstinence syndrome (NAS) and two third of them needed morphine medication for it. Maternal smoking over ten cigarettes per day aggravated and benzodiazepine use attenuated NAS. An infant s highest urinary norbuprenorphine concentration during their first 3 days of life correlated with the duration of morphine treatment. The average length of infant s hospital stay was 25 days.

Quantification problems in the design of forest policy programs.

XVIII IUFRO World Congress, Ljubljana 1986.

Private and municipal forests and the forestry planning system in Japan - trends and problems after World War II.

XVIII IUFRO World Congress, Ljubljana 1986.

Optimisation problems in wireless sensor networks

This thesis studies optimisation problems related to modern large-scale distributed systems, such as wireless sensor networks and wireless ad-hoc networks. The concrete tasks that we use as motivating examples are the following: (i) maximising the lifetime of a battery-powered wireless sensor network, (ii) maximising the capacity of a wireless communication network, and (iii) minimising the number of sensors in a surveillance application. A sensor node consumes energy both when it is transmitting or forwarding data, and when it is performing measurements. Hence task (i), lifetime maximisation, can be approached from two different perspectives. First, we can seek for optimal data flows that make the most out of the energy resources available in the network; such optimisation problems are examples of so-called max-min linear programs. Second, we can conserve energy by putting redundant sensors into sleep mode; we arrive at the sleep scheduling problem, in which the objective is to find an optimal schedule that determines when each sensor node is asleep and when it is awake. In a wireless network simultaneous radio transmissions may interfere with each other. Task (ii), capacity maximisation, therefore gives rise to another scheduling problem, the activity scheduling problem, in which the objective is to find a minimum-length conflict-free schedule that satisfies the data transmission requirements of all wireless communication links. Task (iii), minimising the number of sensors, is related to the classical graph problem of finding a minimum dominating set. However, if we are not only interested in detecting an intruder but also locating the intruder, it is not sufficient to solve the dominating set problem; formulations such as minimum-size identifying codes and locating–dominating codes are more appropriate. This thesis presents approximation algorithms for each of these optimisation problems, i.e., for max-min linear programs, sleep scheduling, activity scheduling, identifying codes, and locating–dominating codes. Two complementary approaches are taken. The main focus is on local algorithms, which are constant-time distributed algorithms. The contributions include local approximation algorithms for max-min linear programs, sleep scheduling, and activity scheduling. In the case of max-min linear programs, tight upper and lower bounds are proved for the best possible approximation ratio that can be achieved by any local algorithm. The second approach is the study of centralised polynomial-time algorithms in local graphs – these are geometric graphs whose structure exhibits spatial locality. Among other contributions, it is shown that while identifying codes and locating–dominating codes are hard to approximate in general graphs, they admit a polynomial-time approximation scheme in local graphs.

Some nonstandard error analysis of discontinuous Galerkin methods for elliptic problems

An a priori error analysis of discontinuous Galerkin methods for a general elliptic problem is derived under a mild elliptic regularity assumption on the solution. This is accomplished by using some techniques from a posteriori error analysis. The model problem is assumed to satisfy a GAyenrding type inequality. Optimal order L (2) norm a priori error estimates are derived for an adjoint consistent interior penalty method.

Attitudes towards suicide among Master’s degree students: a cross-cultural comparison between China and Finland

Attitudes towards suicide among Master’s degree students in Chang Sha (China) and Helsinki (Finland) were compared in order to explore possible cross-cultural differences. The sample included 206 Master’s degree students, 101 Chinese and 105 Finnish. Data were collected using the 30-item Multi-Attitudes Suicide Tendency Scale (MAST) and a demographic information form. According to the results, both Chinese and Finnish students held positive attitudes towards life, they held contradictory attitudes towards suicide, with Finnish students having more permissive and liberal attitudes towards suicide than their Chinese counterparts. In addition, three socio-demographic characteristics, namely religion, family structure, and economic status, associated with attitudes towards suicide among the Chinese Master’s degree students; meanwhile, all socio-demographic characteristics, including gender, religion, major subject, family structure, economic status, and received social support related to attitudes towards suicide among the Finnish Master’s degree students. However, after examining the interaction effect between socio-demographics and cultural backgrounds on attitudes towards suicide, the attitudes of Chinese students were more related to gender, marital status, family economic status, and received social support, whereas Finnish students were more influenced by religion. These findings suggest that culture plays an important role in shaping country-specific differences in attitudes towards suicide and their association with socio-demographic characteristics. Understanding individual attitudes towards suicide could help in intervention to prevent the development of suicidal ideation and in providing appropriate psychological counseling to reduce mental problems. Therefore, these cross-cultural differences may provide indications on how to conduct suicide prevention programs while considering culture-specific contexts.