Choice of Optimal MembraneProcesses for Economical Treatment of Paper Machine Clear Filtrate

In this thesis membrane filtration of paper machnie clear filtrate was studied. The aim of the study was to find membrane processes which are able to produce economically water of sufficient purity from paper machine white water or its saveall clarified fractions for reuse in the paper machnie short circulation. Factors affecting membrane fouling in this application were also studied. The thesis gives an overview af experiments done on a laboratory and a pilot scale with several different membranes and membrane modules. The results were judged by the obtained flux, the fouling tendency and the permeate quality assessed with various chemical analyses. It was shown that membrane modules which used a turbulence promotor of some kind gave the highest fluexes. However, the results showed that the greater the reduction in the concentration polarisation layer caused by increased turbulence in the module, the smaller the reductions in measured substances. Out of the micro-, ultra- and nanofiltration membranes tested, only nanofiltration memebranes produced permeate whose quality was very close to that of the chemically treated raw water used as fresh water in most paper mills today and which should thus be well suited for reuse as shower water both in the wire and press section. It was also shown that a one stage nanofiltration process was more effective than processes in which micro- or ultrafiltration was used as pretreatment for nanofiltration. It was generally observed that acidic pH, high organic matter content, the presence of multivalent ions, hydrophobic membrane material and high membrane cutoff increased the fouling tendency of the membranes.

Studies on integrating kinematic design method with mechanical systems simulation techniques

Theultimate goal of any research in the mechanism/kinematic/design area may be called predictive design, ie the optimisation of mechanism proportions in the design stage without requiring extensive life and wear testing. This is an ambitious goal and can be realised through development and refinement of numerical (computational) technology in order to facilitate the design analysis and optimisation of complex mechanisms, mechanical components and systems. As a part of the systematic design methodology this thesis concentrates on kinematic synthesis (kinematic design and analysis) methods in the mechanism synthesis process. The main task of kinematic design is to find all possible solutions in the form of structural parameters to accomplish the desired requirements of motion. Main formulations of kinematic design can be broadly divided to exact synthesis and approximate synthesis formulations. The exact synthesis formulation is based in solving n linear or nonlinear equations in n variables and the solutions for the problem areget by adopting closed form classical or modern algebraic solution methods or using numerical solution methods based on the polynomial continuation or homotopy. The approximate synthesis formulations is based on minimising the approximation error by direct optimisation The main drawbacks of exact synthesis formulationare: (ia) limitations of number of design specifications and (iia) failure in handling design constraints- especially inequality constraints. The main drawbacks of approximate synthesis formulations are: (ib) it is difficult to choose a proper initial linkage and (iib) it is hard to find more than one solution. Recentformulations in solving the approximate synthesis problem adopts polynomial continuation providing several solutions, but it can not handle inequality const-raints. Based on the practical design needs the mixed exact-approximate position synthesis with two exact and an unlimited number of approximate positions has also been developed. The solutions space is presented as a ground pivot map but thepole between the exact positions cannot be selected as a ground pivot. In this thesis the exact synthesis problem of planar mechanism is solved by generating all possible solutions for the optimisation process ¿ including solutions in positive dimensional solution sets - within inequality constraints of structural parameters. Through the literature research it is first shown that the algebraic and numerical solution methods ¿ used in the research area of computational kinematics ¿ are capable of solving non-parametric algebraic systems of n equations inn variables and cannot handle the singularities associated with positive-dimensional solution sets. In this thesis the problem of positive-dimensional solutionsets is solved adopting the main principles from mathematical research area of algebraic geometry in solving parametric ( in the mathematical sense that all parameter values are considered ¿ including the degenerate cases ¿ for which the system is solvable ) algebraic systems of n equations and at least n+1 variables.Adopting the developed solution method in solving the dyadic equations in direct polynomial form in two- to three-precision-points it has been algebraically proved and numerically demonstrated that the map of the ground pivots is ambiguousand that the singularities associated with positive-dimensional solution sets can be solved. The positive-dimensional solution sets associated with the poles might contain physically meaningful solutions in the form of optimal defectfree mechanisms. Traditionally the mechanism optimisation of hydraulically driven boommechanisms is done at early state of the design process. This will result in optimal component design rather than optimal system level design. Modern mechanismoptimisation at system level demands integration of kinematic design methods with mechanical system simulation techniques. In this thesis a new kinematic design method for hydraulically driven boom mechanism is developed and integrated in mechanical system simulation techniques. The developed kinematic design method is based on the combinations of two-precision-point formulation and on optimisation ( with mathematical programming techniques or adopting optimisation methods based on probability and statistics ) of substructures using calculated criteria from the system level response of multidegree-of-freedom mechanisms. Eg. by adopting the mixed exact-approximate position synthesis in direct optimisation (using mathematical programming techniques) with two exact positions and an unlimitednumber of approximate positions the drawbacks of (ia)-(iib) has been cancelled.The design principles of the developed method are based on the design-tree -approach of the mechanical systems and the design method ¿ in principle ¿ is capable of capturing the interrelationship between kinematic and dynamic synthesis simultaneously when the developed kinematic design method is integrated with the mechanical system simulation techniques.

FPGA-Based Control Design for Power Electronic Applications

Tehoelektoniikkalaitteella tarkoitetaan ohjaus- ja säätöjärjestelmää, jolla sähköä muokataan saatavilla olevasta muodosta haluttuun uuteen muotoon ja samalla hallitaan sähköisen tehon virtausta lähteestä käyttökohteeseen. Tämä siis eroaa signaalielektroniikasta, jossa sähköllä tyypillisesti siirretään tietoa hyödyntäen eri tiloja. Tehoelektroniikkalaitteita vertailtaessa katsotaan yleensä niiden luotettavuutta, kokoa, tehokkuutta, säätötarkkuutta ja tietysti hintaa. Tyypillisiä tehoelektroniikkalaitteita ovat taajuudenmuuttajat, UPS (Uninterruptible Power Supply) -laitteet, hitsauskoneet, induktiokuumentimet sekä erilaiset teholähteet. Perinteisesti näiden laitteiden ohjaus toteutetaan käyttäen mikroprosessoreja, ASIC- (Application Specific Integrated Circuit) tai IC (Intergrated Circuit) -piirejä sekä analogisia säätimiä. Tässä tutkimuksessa on analysoitu FPGA (Field Programmable Gate Array) -piirien soveltuvuutta tehoelektroniikan ohjaukseen. FPGA-piirien rakenne muodostuu erilaisista loogisista elementeistä ja niiden välisistä yhdysjohdoista.Loogiset elementit ovat porttipiirejä ja kiikkuja. Yhdysjohdot ja loogiset elementit ovat piirissä kiinteitä eikä koostumusta tai lukumäärää voi jälkikäteen muuttaa. Ohjelmoitavuus syntyy elementtien välisistä liitännöistä. Piirissä on lukuisia, jopa miljoonia kytkimiä, joiden asento voidaan asettaa. Siten piirin peruselementeistä voidaan muodostaa lukematon määrä erilaisia toiminnallisia kokonaisuuksia. FPGA-piirejä on pitkään käytetty kommunikointialan tuotteissa ja siksi niiden kehitys on viime vuosina ollut nopeaa. Samalla hinnat ovat pudonneet. Tästä johtuen FPGA-piiristä on tullut kiinnostava vaihtoehto myös tehoelektroniikkalaitteiden ohjaukseen. Väitöstyössä FPGA-piirien käytön soveltuvuutta on tutkittu käyttäen kahta vaativaa ja erilaista käytännön tehoelektroniikkalaitetta: taajuudenmuuttajaa ja hitsauskonetta. Molempiin testikohteisiin rakennettiin alan suomalaisten teollisuusyritysten kanssa soveltuvat prototyypit,joiden ohjauselektroniikka muutettiin FPGA-pohjaiseksi. Lisäksi kehitettiin tätä uutta tekniikkaa hyödyntävät uudentyyppiset ohjausmenetelmät. Prototyyppien toimivuutta verrattiin vastaaviin perinteisillä menetelmillä ohjattuihin kaupallisiin tuotteisiin ja havaittiin FPGA-piirien mahdollistaman rinnakkaisen laskennantuomat edut molempien tehoelektroniikkalaitteiden toimivuudessa. Työssä on myösesitetty uusia menetelmiä ja työkaluja FPGA-pohjaisen säätöjärjestelmän kehitykseen ja testaukseen. Esitetyillä menetelmillä tuotteiden kehitys saadaan mahdollisimman nopeaksi ja tehokkaaksi. Lisäksi työssä on kehitetty FPGA:n sisäinen ohjaus- ja kommunikointiväylärakenne, joka palvelee tehoelektroniikkalaitteiden ohjaussovelluksia. Uusi kommunikointirakenne edistää lisäksi jo tehtyjen osajärjestelmien uudelleen käytettävyyttä tulevissa sovelluksissa ja tuotesukupolvissa.

Numerical and ExperimentalModelling of Gas Flow and Heat Transfer in the Air Gap of An Electric Machine

This work deals with the cooling of high-speed electric machines, such as motors and generators, through an air gap. It consists of numerical and experimental modelling of gas flow and heat transfer in an annular channel. Velocity and temperature profiles are modelled in the air gap of a high-speed testmachine. Local and mean heat transfer coefficients and total friction coefficients are attained for a smooth rotor-stator combination at a large velocity range. The aim is to solve the heat transfer numerically and experimentally. The FINFLO software, developed at Helsinki University of Technology, has been used in the flow solution, and the commercial IGG and Field view programs for the grid generation and post processing. The annular channel is discretized as a sector mesh. Calculation is performed with constant mass flow rate on six rotational speeds. The effect of turbulence is calculated using three turbulence models. The friction coefficient and velocity factor are attained via total friction power. The first part of experimental section consists of finding the proper sensors and calibrating them in a straight pipe. After preliminary tests, a RdF-sensor is glued on the walls of stator and rotor surfaces. Telemetry is needed to be able to measure the heat transfer coefficients at the rotor. The mean heat transfer coefficients are measured in a test machine on four cooling air mass flow rates at a wide Couette Reynolds number range. The calculated values concerning the friction and heat transfer coefficients are compared with measured and semi-empirical data. Heat is transferred from the hotter stator and rotor surfaces to the coolerair flow in the air gap, not from the rotor to the stator via the air gap, althought the stator temperature is lower than the rotor temperature. The calculatedfriction coefficients fits well with the semi-empirical equations and precedingmeasurements. On constant mass flow rate the rotor heat transfer coefficient attains a saturation point at a higher rotational speed, while the heat transfer coefficient of the stator grows uniformly. The magnitudes of the heat transfer coefficients are almost constant with different turbulence models. The calibrationof sensors in a straight pipe is only an advisory step in the selection process. Telemetry is tested in the pipe conditions and compared to the same measurements with a plain sensor. The magnitudes of the measured data and the data from the semi-empirical equation are higher for the heat transfer coefficients than thenumerical data considered on the velocity range. Friction and heat transfer coefficients are presented in a large velocity range in the report. The goals are reached acceptably using numerical and experimental research. The next challenge is to achieve results for grooved stator-rotor combinations. The work contains also results for an air gap with a grooved stator with 36 slots. The velocity field by the numerical method does not match in every respect the estimated flow mode. The absence of secondary Taylor vortices is evident when using time averagednumerical simulation.

A user-friendly web portal for T-Coffee on supercomputers

Background: Parallel T-Coffee (PTC) was the first parallel implementation of the T-Coffee multiple sequence alignment tool. It is based on MPI and RMA mechanisms. Its purpose is to reduce the execution time of the large-scale sequence alignments. It can be run on distributed memory clusters allowing users to align data sets consisting of hundreds of proteins within a reasonable time. However, most of the potential users of this tool are not familiar with the use of grids or supercomputers. Results: In this paper we show how PTC can be easily deployed and controlled on a super computer architecture using a web portal developed using Rapid. Rapid is a tool for efficiently generating standardized portlets for a wide range of applications and the approach described here is generic enough to be applied to other applications, or to deploy PTC on different HPC environments. Conclusions: The PTC portal allows users to upload a large number of sequences to be aligned by the parallel version of TC that cannot be aligned by a single machine due to memory and execution time constraints. The web portal provides a user-friendly solution.

The importance of sonographer experience and machine quality with regards to the role of musculoskeletal ultrasound in routine care of rheumatoid arthritis patients.

OBJECTIVES: Regarding recent progress, musculoskeletal ultrasound (US) will probably soon be integrated in standard care of patient with rheumatoid arthritis (RA). However, in daily care, quality of US machines and level of experience of sonographers are varied. We conducted a study to assess reproducibility and feasibility of an US scoring for RA, including US devices of different quality and rheumatologist with various levels of expertise in US as it would be in daily care. METHODS: The Swiss Sonography in Arthritis and Rheumatism (SONAR) group has developed a semi-quantitative score using OMERACT criteria for synovitis and erosion in RA. The score was taught to 108 rheumatologists trained in US. One year after the last workshop, 19 rheumatologists participated in the study. Scans were performed on 6 US machines ranging from low to high quality, each with a different patient. Weighted kappa was calculated for each pair of readers. RESULTS: Overall, the agreement was fair to moderate. Quality of device, experience of the sonographers and practice of the score before the study improved substantially the agreement. Agreement assessed on higher quality machine, among sonographers with good experience in US increased to substantial (median kappa for B-mode and Doppler: 0.64 and 0.41 for erosion). CONCLUSIONS: This study demonstrated feasibility and reproducibility of the Swiss US SONAR score for RA. Our results confirmed importance of the quality of US machine and the training of sonographers for the implementation of US scoring in the routine daily care of RA.

Preferred Spatial Frequencies for Human Face Processing Are Associated with Optimal Class Discrimination in the Machine

Psychophysical studies suggest that humans preferentially use a narrow band of low spatial frequencies for face recognition. Here we asked whether artificial face recognition systems have an improved recognition performance at the same spatial frequencies as humans. To this end, we estimated recognition performance over a large database of face images by computing three discriminability measures: Fisher Linear Discriminant Analysis, Non-Parametric Discriminant Analysis, and Mutual Information. In order to address frequency dependence, discriminabilities were measured as a function of (filtered) image size. All three measures revealed a maximum at the same image sizes, where the spatial frequency content corresponds to the psychophysical found frequencies. Our results therefore support the notion that the critical band of spatial frequencies for face recognition in humans and machines follows from inherent properties of face images, and that the use of these frequencies is associated with optimal face recognition performance.

Level Set Methods in Image Processing

This thesis gives an overview of the use of the level set methods in the field of image science. The similar fast marching method is discussed for comparison, also the narrow band and the particle level set methods are introduced. The level set method is a numerical scheme for representing, deforming and recovering structures in an arbitrary dimensions. It approximates and tracks the moving interfaces, dynamic curves and surfaces. The level set method does not define how and why some boundary is advancing the way it is but simply represents and tracks the boundary. The principal idea of the level set method is to represent the N dimensional boundary in the N+l dimensions. This gives the generality to represent even the complex boundaries. The level set methods can be powerful tools to represent dynamic boundaries, but they can require lot of computing power. Specially the basic level set method have considerable computational burden. This burden can be alleviated with more sophisticated versions of the level set algorithm like the narrow band level set method or with the programmable hardware implementation. Also the parallel approach can be used in suitable applications. It is concluded that these methods can be used in a quite broad range of image applications, like computer vision and graphics, scientific visualization and also to solve problems in computational physics. Level set methods and methods derived and inspired by it will be in the front line of image processing also in the future.

LWC-SYVÄPAINOHIOKKEEN LAADUN OPTIMOINTI

Työn tavoitteena oli hiokkeen laatua optimoimalla löytää keinoja pohjapaperin opasiteetin parantamiseksi. Tehtaalla oli havaittu hiokkeen palstautumislujuuden pudonneen ja pian tämän jälkeen oli paperikoneella nostettu sellun jauhatustehoa mikä puolestaan vaikuttaa negatiivisesti pohjapaperin opasiteettiin. Päähuomio hiokkeen laadun optimoinnissa keskitettiin tästä syystä palstautumislujuuden tason nostamiseen. Kirjallisuuden mukaan tärkein hiokkeen palstautumislujuuteen ja myös opasiteettiin vaikuttava tekijä on massan hienoaines. Hiokkeen hienoainespitoisuuden lisäämistä tutkittiin tässä työssä seuraavalla kolmella tavalla: rejektijauhatuksen optimointi, kivenalusmassan CSF-tason alentaminen ja jälkijauhatustehon lisääminen. Työn toisena tavoitteena oli varmistaa rejektilinjan kapasiteetin riittävyys, erityisesti rejektilajitin 6:n osalta. Taustana tälle tarkastelulle oli mahdollisen lisälajittimen investointitarve RL 6:n rinnalle. Rejektijauhatuksen optimoinnissa tutkittiin jauhatustehon, eri terämallien ja kahden rinnakkaisen rejektijauhimen (yhden sijasta) vaikutusta jauhetun rejektimassan ominaisuuksiin. Pidättävillä rejektijauhimen terillä jauhetusta massasta tuli pitkäkuituisempaa kuin referenssiterillä, joissa staattori oli pumppaava ja roottori pidättävä. Mutta vaikka pidättävillä terillä jauhettu massa oli pitkäkuituisempaa ja sisälsi vähemmän hienoainetta oli sen palstautumislujuus samaa luokkaa kuin referenssiterillä jauhetun massan. Kahden rinnakkaisen jauhimen ajomallilla saatiin laadultaan kaikein heikointa massaa. Kaikissa koeajoissa saatiin rejektimassan palstautumislujuutta parannettua jauhatustehoa lisäämällä. Kivenalusmassan CSF-tasoa alentamalla ei valmiin annosteluhiokkeen palstautumislujuus alentunut vaikka hiokkeen hienoainespitoisuus kasvoi hieman. Mutta vaikka hiokkeen palstautumislujuus ei kasvanutkaan niin koejaksolla, joka oli pituudeltaan hieman yli kuukauden, pohjapaperin opasiteetti kuitenkin parani hieman ja sellun jauhatustehoa voitiin paperikoneella pudottaa hieman. Palstautumislujuuskartoituksen, jossa otettiin näytteitä hiomon eri prosessivaiheista, mukaan jälkijauhatus oli yksittäisenä prosessivaiheena eniten hiokkeen palstautumislujuuteen vaikuttava prosessivaihe. Jälkijauhatuskoeajosta saatiinkiin parhaimmat tulokset hienoainespitoisuuden ja palstautumislujuuden nousun suhteen. Rejektilajittelun massarejektisuhteiden määritysten ja rejektilajitin 6:n kapasiteettikokeen mukaan rejektilajittelu toimii nykyisellä tuotantomäärällä halutunlaisesti ja rejektilajitin 6:n osalta tuotantoa on vielä varaa nostaakin.

Measurement of the air permeability profile on SC paper machine

Tämän diplomityön tarkoituksena oli asentaa ja kehittää UPM-Kymmene Rauman tehtaiden PK2:lle luotettava ja toimiva ilmanläpäisyprofiilin mittaus. Työn tarkoituksena oli myös kartoittaa tietoja ilmanläpäisyprofiiliin vaikuttavista seikoista sekä mahdollisuuksista säätää ilmanläpäisyprofiilia. Lisäksi työn tavoitteena oli löytää toimiva menetelmä verrata online mitattua ilmanläpäisyprofiilia laboratoriossa mitattuun ilmanläpäisyprofiiliin online mittauksen luotettavuuden näkökulmasta. Työn aikana selvitettiin myös ilmanläpäisyprofiilin mittauksen mahdollisuutta superkalanteroidusta SC paperista. Työn kirjallisessa osassa käsiteltiin paperin huokoisuutta ja ilmanläpäisyä, huokoisuustasoon ja huokoisuus profiiliin vaikuttavia tekijöitä, ilmanläpäisevyyden merkitystä SC paperin valmistukselle ja SC paperin painettavuudelle sekä ilmanläpäisevyyden laboratorio- sekä online mittausta. Kirjallisessa osassa käsiteltiin myös Honeywellin uutta Poros ilmanläpäisysensoria. Työn kokeellisessa osassa tutkittiin ilmanläpäisyprofiilimittauksen luotettavuutta CD ja MD suunnassa sekä laboratorio- ja online-mittausten välisiä eroavaisuuksia ennen PK2 uusintaa. PK2 uusinnan jälkeen kokeellisessa osassa keskityttiin luotettavuuden varmentamiseen CD ja MD suunnassa sekä kartoittamaan tekijöitä, jotka aiheuttivat pieniä tasoeroja mittausten välillä. Mittaukset todettiin luotettaviksi ja niiden pohjalta suoritettiin mitattujen online profiilien välisiä vertailuja. Ilmanläpäisyprofiililla todettiin olevan positiivinen korrelaatio neliömassaprofiilin ja kosteusprofiilin kanssa sekä negatiivinen korrelaatio tuhkaprofiilin kanssa. PK2 uusinnan yhteydessä tehtiin koeajoja, jotka liittyivät laadunoptimointiin viira- ja puristinosalla. Koeajoissa tutkittujen asioiden lisäksi tutkittiin muutettujen parametrien vaikutusta ilmanläpäisyprofiiliin. Höyrylaatikon vaikutusta ilmanläpäisyprofiiliin tutkittiin säätöjen virityksen yhteydessä.

Parallel feedback loops control the basal activity of the HOG MAPK signaling cascade.

Tight regulation of the MAP kinase Hog1 is crucial for survival under changing osmotic conditions. Interestingly, we found that Hog1 phosphorylates multiple upstream components, implying feedback regulation within the signaling cascade. Taking advantage of an unexpected link between glucose availability and Hog1 activity, we used quantitative single cell measurements and computational modeling to unravel feedback regulation operating in addition to the well-known adaptation feedback triggered by glycerol accumulation. Indeed, we found that Hog1 phosphorylates its activating kinase Ssk2 on several sites, and cells expressing a non-phosphorylatable Ssk2 mutant are partially defective for feedback regulation and proper control of basal Hog1 activity. Together, our data suggest that Hog1 activity is controlled by intertwined regulatory mechanisms operating with varying kinetics, which together tune the Hog1 response to balance basal Hog1 activity and its steady-state level after adaptation to high osmolarity.

Predicting diffusion of innovations with self-organisation and machine learning

The main subject of this master's thesis was predicting diffusion of innovations. The prediction was done in a special case: product has been available in some countries, and based on its diffusion in those countries the prediction is done for other countries. The prediction was based on finding similar countries with Self-Organizing Map~(SOM), using parameters of countries. Parameters included various economical and social key figures. SOM was optimised for different products using two different methods: (a) by adding diffusion information of products to the country parameters, and (b) by weighting the country parameters based on their importance for the diffusion of different products. A novel method using Differential Evolution (DE) was developed to solve the latter, highly non-linear optimisation problem. Results were fairly good. The prediction method seems to be on a solid theoretical foundation. The results based on country data were good. Instead, optimisation for different products did not generally offer clear benefit, but in some cases the improvement was clearly noticeable. The weights found for the parameters of the countries with the developed SOM optimisation method were interesting, and most of them could be explained by properties of the products.

Liikesimulaattorialustan kehittäminen virtuaaliprototyypin avulla

Työn tarkoituksena oli kehittää kuuden vapausasteen liikesimulaattorialusta virtuaaliprototyypin avulla siten, että alustan dynamiikka mallinnetaan Adams-ohjelmistolla ja ohjaus- ja säätöpiiri Matlab Simulink:llä. Tarkoituksena oli tutkia dynaamisen mallin ja säätöteknisen mallin yhdistämistä ja niiden yhteen toimimista. Tarkoituksena oli myös selvittää tulevaisuudessa rakennettavan Stewart:n alustan mekaniikan mitat ja hydraulikomponenttien koot. Työssä tutkittiin alustan käyttäytymistä halutulla liikealueella, nopeuksia joita saavutetaan ja mekaanisia rajoitteita. Työn tuloksesta on tarkoitus rakentaa fyysinen prototyyppi liittyen KONSI-projektiin, jossa kehitetään satamanosturisimulaattori nosturiohjaajan koulutuksen tueksi. Malli tullaan kytkemään Teppo Lehtisen diplomityönä tehtyyn satamanosturi kontin simulointimalliin ja koko järjestelmän on tarkoitus toimia reaaliaikaisena.

Offset-print mottling measurement using machine vision

Mottling is one of the key defects in offset-printing. Mottling can be defined as unwanted unevenness of print. In this work, diameter of a mottle spot is defined between 0.5-10.0 mm. There are several types of mottling, but the reason behind the problem is still not fully understood. Several commercial machine vision products for the evaluation of print unevenness have been presented. Two of these methods used in these products have been implemented in this thesis. The one is the cluster method and the other is the band-pass method. The properties of human vision system have been taken into account in the implementation of these two methods. An index produced by the cluster method is a weighted sum of the number of found spots, and an index produced by band-pass method is a weighted sum of coefficients of variations of gray-levels for each spatial band. Both methods produce larger indices for visually poor samples, so they can discern good samples from the poor ones. The difference between the indices for good and poor samples is slightly larger produced by the cluster method. 11 However, without the samples evaluated by human experts, the goodness of these results is still questionable. This comparison will be left to the next phase of the project.