32 resultados para Steel angles and straps
em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland
Resumo:
In recent times of global turmoil, the need for uncertainty management has become ever momentous. The need for enhanced foresight especially concerns capital-intensive industries, which need to commit their resources and assets with long-term planning horizons. Scenario planning has been acknowledged to have many virtues - and limitations - concerning the mapping of the future and illustrating the alternative development paths. The present study has been initiated to address both the need of improved foresight in two capital-intensive industries, i.e. the paper and steel industries and the imperfections in the current scenario practice. The research problem has been approached by engendering a problem-solving vehicle, which combines, e.g. elements of generic scenario process, face-to-face group support methods, deductive scenario reasoning and causal mapping into a fully integrated scenario process. The process, called the SAGES scenario framework, has been empirically tested by creating alternative futures for two capital-intensive industries, i.e. the paper and steel industries. Three scenarios for each industry have been engendered together with the identification of the key megatrends, the most important foreign investment determinants, key future drivers and leading indicators for the materialisation of the scenarios. The empirical results revealed a two-fold outlook for the paper industry, while the steel industry future was seen as much more positive. The research found support for utilising group support systems in scenario and strategic planning context with some limitations. Key perceived benefits include high time-efficiency, productivity and lower resource-intensiveness. Group support also seems to enhance participant satisfaction, encourage innovative thinking and provide the users with personalised qualitative scenarios.
Resumo:
Cutting of thick section stainless steel and mild steel, and medium section aluminium using the high power ytterbium fibre laser has been experimentally investigated in this study. Theoretical models of the laser power requirement for cutting of a metal workpiece and the melt removal rate were also developed. The calculated laser power requirement was correlated to the laser power used for the cutting of 10 mm stainless steel workpiece and 15 mm mild steel workpiece using the ytterbium fibre laser and the CO2 laser. Nitrogen assist gas was used for cutting of stainless steel and oxygen was used for mild steel cutting. It was found that the incident laser power required for cutting at a given cutting speed was lower for fibre laser cutting than for CO2 laser cutting indicating a higher absorptivity of the fibre laser beam by the workpiece and higher melting efficiency for the fibre laser beam than for the CO2 laser beam. The difficulty in achieving an efficient melt removal during high speed cutting of the 15 mmmild steel workpiece with oxygen assist gas using the ytterbium fibre laser can be attributed to the high melting efficiency of the ytterbium fibre laser. The calculated melt flow velocity and melt film thickness correlated well with the location of the boundary layer separation point on the 10 mm stainless steel cut edges. An increase in the melt film thickness caused by deceleration of the melt particles in the boundary layer by the viscous shear forces results in the flow separation. The melt flow velocity increases with an increase in assist gas pressure and cut kerf width resulting in a reduction in the melt film thickness and the boundary layer separation point moves closer to the bottom cut edge. The cut edge quality was examined by visual inspection of the cut samples and measurement of the cut kerf width, boundary layer separation point, cut edge squareness (perpendicularity) deviation, and cut edge surface roughness as output quality factors. Different regions of cut edge quality in 10 mm stainless steel and 4 mm aluminium workpieces were defined for different combinations of cutting speed and laserpower.Optimization of processing parameters for a high cut edge quality in 10 mmstainless steel was demonstrated
Resumo:
Finnish design and consulting companies are delivering robust and cost-efficient steel structures solutions to a large number of manufacturing companies worldwide. Recently introduced EN 1090-2 standard obliges these companies to specify the execution class of steel structures for their customers. This however, requires clarifying, understanding and interpreting the sophisticated procedure of execution class assignment. The objective of this research is to provide a clear explanation and guidance through the process of execution class assignment for a given steel structure and to support the implementation of EN 1090-2 standard in Rejlers Oy, one of Finnish design and consulting companies. This objective is accomplished by creating a guideline for designers that elaborates on the four-step process of the execution class assignment for a steel structure or its part. Steps one to three define the consequence class (projected consequences of structure failure), the service category (hazards associated with the service use exploitation of steel structure) and the production category (manufacturing process peculiarities), based on the ductility class (capacity of structure to withstand deformations) and the behaviour factor (corresponds to structure seismic behaviour). The final step is the execution class assignment taking into account results of previous steps. Main research method is indepth literature review of European standards family for steel structures. Other research approach is a series of interviews of Rejlers Oy representatives and its clients, results of which have been used to evaluate the level of EN 1090-2 awareness. Rejlers Oy will use the developed novel coherent standard implementation guideline to improve its services and to obtain greater customer satisfaction.
Resumo:
The study of price risk management concerning high grade steel alloys and their components was conducted. This study was focused in metal commodities, of which nickel, chrome and molybdenum were in a central role. Also possible hedging instruments and strategies for referred metals were studied. In the literature part main themes are price formation of Ni, Cr and Mo, the functioning of metal exchanges and main hedging instruments for metal commodities. This section also covers how micro and macro variables may affect metal prices from the viewpoint of short as well as longer time period. The experimental part consists of three sections. In the first part, multiple regression model with seven explanatory variables was constructed to describe price behavior of nickel. Results were compared after this with information created with comparable simple regression model. Additionally, long time mean price reversion of nickel was studied. In the second part, theoretical price of CF8M alloy was studied by using nickel, ferro-chrome and ferro-molybdenum as explanatory variables. In the last section, cross hedging possibilities for illiquid FeCr -metal was studied with five LME futures. Also this section covers new information concerning possible forthcoming molybdenum future contracts as well. The results of this study confirm, that linear regression models which are based on the assumption of market rationality, are not able to reliably describe price development of metals at issue. Models fulfilling assumptions for linear regression may though include useful information of statistical significant variables which have effect on metal prices. According to the experimental part, short futures were found to incorporate the most accurate information concerning the price movements in the future. However, not even 3M futures were able to predict turning point in the market before the faced slump. Cross hedging seemed to be very doubtful risk management strategy for illiquid metals, because correlations coefficients were found to be very sensitive for the chosen time span.
Resumo:
Aim of this thesis was to design and manufacture a microdistillation column. The literature review part of this thesis covers stainless steels, material processing and basics about engineering design and distillation. The main focus, however, is on the experimental part. Experimental part is divided into five distinct sections: First part is where the device is introduced and separated into three parts. Secondly the device is designed part by part. It consists mostly of detail problem solving, since the first drawings had already been drawn and the critical dimensions decided. Third part is the manufacture, which was not fully completed since the final assembly was left out of this thesis. Fourth part is the test welding for the device, and its analysis. Finally some ideas for further studies are presented. The main goal of this thesis was accomplished. The device only lacks some final assembly but otherwise it is complete. One thing that became clear during the process was how difficult it is to produce small and precise steel parts with conventional manufacturing methods. Internal stresses within steel plates and thermal distortions can easily ruin small steel structures. Designing appropriate welding jigs is an important task for even simple devices. Laser material processing is a promising tool for this kind of steel processing because of the flexibility, good cutting quality and also precise and low heat input when welding. Next step in this project is the final assembly and the actual distillation tests. The tests will be carried out at Helsinki University of Technology.
Resumo:
The purpose of this thesis is to examine the level of customer consciousness of the production process employees in a steel factory and to investigate the methods of internal marketing in order to propose development practices to enhance the customer consciousness of the case company employees. The significance of the level of customer consciousness is discussed and practices already implemented affecting the level of customer consciousness in the company are examined. The literature review gives an insight to the role of customer consciousness in the CRM philosophy of a manufacturing company and examines the means of internal marketing in enhancing customer consciousness. In the empirical part of the study, the level and significance of customer consciousness is determined by conducting individual and focus group interviews. The interviews are also used to examine the practices that could function in enhancing the customer consciousness of the employees. Development suggestions to improve the level of customer consciousness in the production process are given based on the results. The level of customer consciousness is at a poor level in the production process and influences above all on work motivation and job satisfaction, but possibly on customer satisfaction as well. The enhancement of customer consciousness in the production process should be done e.g. by ensuring the distribution of right knowledge coherently to all of the employees, gathering large customer reference database to exploit in work and in training, using visual illustration in presenting the customer information, training proactively and letting the employees to participate in the customer oriented development activities. Customer satisfaction focused reward system can be considered.
Resumo:
This study investigated the surface hardening of steels via experimental tests using a multi-kilowatt fiber laser as the laser source. The influence of laser power and laser power density on the hardening effect was investigated. The microhardness analysis of various laser hardened steels was done. A thermodynamic model was developed to evaluate the thermal process of the surface treatment of a wide thin steel plate with a Gaussian laser beam. The effect of laser linear oscillation hardening (LLOS) of steel was examined. An as-rolled ferritic-pearlitic steel and a tempered martensitic steel with 0.37 wt% C content were hardened under various laser power levels and laser power densities. The optimum power density that produced the maximum hardness was found to be dependent on the laser power. The effect of laser power density on the produced hardness was revealed. The surface hardness, hardened depth and required laser power density were compared between the samples. Fiber laser was briefly compared with high power diode laser in hardening medium-carbon steel. Microhardness (HV0.01) test was done on seven different laser hardened steels, including rolled steel, quenched and tempered steel, soft annealed alloyed steel and conventionally through-hardened steel consisting of different carbon and alloy contents. The surface hardness and hardened depth were compared among the samples. The effect of grain size on surface hardness of ferritic-pearlitic steel and pearlitic-cementite steel was evaluated. In-grain indentation was done to measure the hardness of pearlitic and cementite structures. The macrohardness of the base material was found to be related to the microhardness of the softer phase structure. The measured microhardness values were compared with the conventional macrohardness (HV5) results. A thermodynamic model was developed to calculate the temperature cycle, Ac1 and Ac3 boundaries, homogenization time and cooling rate. The equations were numerically solved with an error of less than 10-8. The temperature distributions for various thicknesses were compared under different laser traverse speed. The lag of the was verified by experiments done on six different steels. The calculated thermal cycle and hardened depth were compared with measured data. Correction coefficients were applied to the model for AISI 4340 steel. AISI 4340 steel was hardened by laser linear oscillation hardening (LLOS). Equations were derived to calculate the overlapped width of adjacent tracks and the number of overlapped scans in the center of the scanned track. The effect of oscillation frequency on the hardened depth was investigated by microscopic evaluation and hardness measurement. The homogeneity of hardness and hardened depth with different processing parameters were investigated. The hardness profiles were compared with the results obtained with conventional single-track hardening. LLOS was proved to be well suitable for surface hardening in a relatively large rectangular area with considerable depth of hardening. Compared with conventional single-track scanning, LLOS produced notably smaller hardened depths while at 40 and 100 Hz LLOS resulted in higher hardness within a depth of about 0.6 mm.
Resumo:
This thesis is made in cooperation with Laboratory of Steel Structures and the steel company SSAB. Maximization of the benefits of high-strength steel usually requires the usage of thin wall thicknesses. This means the failures related to buckling, distortion and warping stand out. One must be aware of these phenomena to design thin-walled structures stressed with forces such as torsional loading. It is also important to take into account small stress ranges when evaluating the accurate fatigue strength of structures. The objective of this thesis is to clarify the theory of the uniform and non-uniform torsion. This paper focuses on warping due to the non-uniform torsion in double symmetric box girder and structural hollow section. The arisen stress states are explained and researched using the finite element method. Another research target is the distortion in double symmetric box girder due to torsion, and the restraining effect of transverse diaphragms at the load end. Multiple transverse diaphragms are used to study more efficient restraining against warping and distortion than a common one end plate structure.
Resumo:
Työn tavoitteena oli selvittää tilannetta Euroopan automaattiteräsmarkkinoilla ja sen perusteella arvioida Imatra Steelin mahdollisuuksia kilpailla kyseessä olevilla markkinoilla. Tärkein tavoite oli kokonaismarkkinapotentiaalin arvioiminen Saksan, Ruotsin, Englannin ja Suomen markkinoilla. Lisäksi selvitettiin käytetyt automaattiteräslajit ja mitta-alue, hintataso sekä koneistukseenliittyviä teknisiä yksityiskohtia.Tavoitteena oli myös kartoittaa asenteita ja mielipiteitä mahdollisesta lyijyn käytön kieltämisestä teräksen seosaineena tulevaisuudessa. Paremman kokonaiskuvan saamiseksi analysoitiin myös kilpailutilannetta Euroopassa. Työn teoriakehyksessä tutkittiin teollisuustuotteiden markkinatutkimuksen suorittamisen erityispiirteitä, markkinapotentiaalin määrittämiseen liittyviä käsitteitä ja kilpailija-analyysin suorittamista. Empiirinen tutkimus suoritettiin pääasiassa asiantuntijoiden haastattelujen ja kyselyjen avulla. Haastateltavina oli tukkureita ja loppukäyttäjiä. Kilpailutilanteen kartoittaminen perustuu lähinnä sekundääriseen tietoon, Internet-sivuihin ja myyntikonttoreiden aikaisemmin keräämään tietoon.Automaattiterästen kokonaispotentiaaliksi Euroopassa arvioitiin miljoona tonnia ja suurin osa kaupasta käydään tutkituilla markkina-alueilla. Suurimmat volyymit sijoittuvat pienemmille mitta-alueille, Æ 12 - 50 mm. Markkinoita hallitsee muutama suuri teräksen valmistaja. Imatra Steel kohtuullisen pienenä toimittajana ei pysty kilpailemaan volyymilla ja tuotevalikoimallaan suurten teräsjättien kanssa. Imatra Steelin mahdollinen strategiavaihtoehto olisi yrittää löytää ne kapeat segmentit ja markkinaraot, joilla sen tuotteet jatietotaito tuovat asiakkaalle suurimman mahdollisen hyödyn verrattuna kilpailijoihin.
Resumo:
Tässä työssä tutkittiin suotautuneen massakakun adheesiota teräspinnalle. Muuttujina käytettiin tyypillisiä pesuprosessin arvoja. Lisäksi tutkittiin teollisessa pesulaitteessa massakakun irrotuksessa käytettävän paineilmapulssin käyttäytymistä. Kirjallisuusosassa tarkasteltiin suotautuneen massakakun muodostumista, adheesiota ja adheesioon vaikuttavia tekijöitä massakakun irrotuksen kannalta. Lisäksi massakakun irrotuksessa käytettävän paineilman virtaustatarkasteltiin adiabaattisena virtauksena. Kokeellisen osan irrotuskokeissa tutkittiin suotautuneen massakakun adheesiovoimia teräksisen kartion laitoihin ja reikälevyyn. Kokeissa tutkittiin tyypillisten prosessi-muuttujien kuten lämpötilan, pH:n ja kuiva-ainepitoisuuden vaikutusta tarvittavaan kakun irrotusvoimaan. Lisäksi tutkittiin myös kartion kulman ja pinnanlaadun vaikutusta. Adheesiokokeiden perusteella pystyttiin laskemaan massakakun irrotukseen tarvittava rajapaine teollisen pesulaitteen lokeron suodoskanavassa. Kokeellisen osan paineilmakokeissa tutkittiin irrotuksessa käytettävän paineilman painevaikutusta ja virtausta teollisen pesulaitteen lokerossa ja näihin vaikuttavia rakenteellisten ja prosessiteknisten parametrien vaikutusta. Lisäksi tutkimusta täydennettiin videokuvauksen avulla tutkimalla paineaallon etenemistä merkkiaineen avulla.
Resumo:
Tämän diplomityön aiheena on lähtölogistiikan strateginen tarkastelu tutkimuksen kohdeyrityksenä olevassa terästehtaassa. Tavoitteena oli lähtölogistiikan tulevaisuusskenaarioiden laatiminen. Diplomityössä tarkastellaan mm. logistiikan epävarmuustekijöitä ja haasteita, erilaisten kuljetusmuotojen käyttöä sekä kohdeyrityksen materiaalivirtojen suuntautumista tulevaisuudessa. Työssä luodaan katsaus logistisen asiakaspalvelun elementteihin ja tutkitaan, mitä elementtejä asiakkaat pitävät tärkeinä. Lisäksi tarkastellaan, miten asiakkaiden vaatimukset kehittyvät tulevaisuudessa. Tutkimus toteutettiin laadullisena tapaustutkimuksena. Empiirinen aineisto kerättiin haastattelujen, sähköpostikyselyn sekä havainnoinnin avulla. Diplomityössä laadittujen skenaarioiden aiheiksi valikoituivat kuljettaminen, Venäjä sekä tuotteet, volyymi ja markkina-alueet. Positiivisen skenaarion mukaan kasvavat materiaalivirrat suuntautuvat Suomen lisäksi Ruotsiin, Keski-Eurooppaan sekä Itä-Eurooppaan, joka on noussut uudeksi markkina-alueeksi. Negatiivisessa skenaariossa kilpailu on kiristynyt ja Ovako Imatran asiakkaat ovat muuttaneet joukolla Aasiaan, jonne teräksen vieminen Suomesta ei olekannattavaa. Tutkimus osoitti, että trendi tilauserien pienentymisestä ja toimitussyklin tihentymisestä pätee myös Ovako Imatran asiakkaiden kohdalla. Erityisen tärkeiksi logistisen asiakaspalvelun elementeiksi nousivat toimitusvarmuus sekä joustavuus toimituksissa. Tutkimuksessa havaittiin, että asiakkaat haluaisivat saada informaatiota tuotteen toimitustilasta online-järjestelmän kautta.
Resumo:
Thisresearch deals with the dynamic modeling of gas lubricated tilting pad journal bearings provided with spring supported pads, including experimental verification of the computation. On the basis of a mathematical model of a film bearing, a computer program has been developed, which can be used for the simulation of a special type of tilting pad gas journal bearing supported by a rotary spring under different loading conditions time dependently (transient running conditions due to geometry variations in time externally imposed). On the basis of literature, different transformations have been used in the model to achieve simpler calculation. The numerical simulation is used to solve a non-stationary case of a gasfilm. The simulation results were compared with literature results in a stationary case (steady running conditions) and they were found to be equal. In addition to this, comparisons were made with a number of stationary and non-stationary bearing tests, which were performed at Lappeenranta University of Technology using bearings designed with the simulation program. A study was also made using numerical simulation and literature to establish the influence of the different bearing parameters on the stability of the bearing. Comparison work was done with literature on tilting pad gas bearings. This bearing type is rarely used. One literature reference has studied the same bearing type as that used in LUT. A new design of tilting pad gas bearing is introduced. It is based on a stainless steel body and electron beam welding of the bearing parts. It has good operation characteristics and is easier to tune and faster to manufacture than traditional constructions. It is also suitable for large serial production.
Resumo:
Tämän diplomityön tavoitteena oli löytää prosessiparametrejä nestepakkauskartongin reuna-alueiden kuivatuskutistuman hallintaan ja saada tuotteen reuna-alueiden sileystaso paremmaksi. Tarkoituksena oli parantaa reuna-alueiden painettavuusominaisuuksia sekä saada koneen poikkisuunnassa laadultaan parempi tuote. Työn kirjallisuusosassa on tarkasteltu työn kannalta nestepakkauskartongin kriittisimpiä ominaisuuksia, sileyttä ja jäykkyyttä. Lisäksi kirjallisuusosassa on tarkasteltu kuitujen ominaisuuksia, sylinterikuivatusta ja kuivatuskutistumaa. Kokeellisessa osassa on etsitty esitutkimuksella prosessiparametrejä, jotka ovat aiheuttaneet poikkisuunnan sileyserojen kasvun kartonkikoneen investoinnin jälkeen. Suoria korrelaatioita prosessiparametrien ja kuivatuskutistuman välille ei löydetty. Kokeellisen osan tehdasmittakaavaisissa koeajoissa tutkittiin kahdeksan eri parametrin vaikutusta kuivatuskutistumaan, jotka perustuivat kirjallisuuteen. Tutkituista parametreistä huulisuihkun iskukulman muutoksella sekä konesuuntaisella kuivatusprofiililla ei ollut vaikutusta kuivatuskutistumaan. Runkokerroksen mäntysellun korvaaminen koivusellulla vähensi kuivatuskutistumaa ja lisäsi sileyttä, mutta tuotteen palstautumislujuus ei tällöin ollut riittävä. Retentiokemikaalien reseptimuutoksilla pinta- ja taustakerroksen välillä, kuivatusosan nollatason laskulla ja perälaatikkosakeuksien pienentämisellä oli vähän vaikutusta kuivatuskutistumaan. Vaikutus reuna-alueiden sileyteen oli kuitenkin vähemmän kuin 10 %. Diplomityön perusteella kuivatusosan nopeuseroilla ja kuivatusviirojen kireyksillä oli suurin vaikutusta kuivatuskutistumaan ja reuna-alueiden sileystasoon. Lisäämällä nopeuseroja ja kiristämällä kuivatusviiroja reuna-alueiden sileyttä pystyttiin parantamaan yli 20 %.
Resumo:
Suomessa on tapahtunut 2000-luvulla neljä kappaletta ns. suuronnettomuuden vaaratilanteiksi luokiteltavaa teräsrakenteiden vaurioitumisesta aiheutunutta onnettomuutta, joista yksi johti ihmishengen menetykseen. Onnettomuuden syynä oli huonolaatuisten pienahitsien pettäminen kuormituksen alaisena, joka puolestaan oli seurausta puutteellisesta hitsauksen laadunvarmistuksesta. Teräsrakenteiden valmistus ja hitsaus eivät ole yhtä tarkan viranomaisvalvonnan alaista kuten esimerkiksi painelaitteiden valmistus, vaikka teräsrakenteiden vaurioitumisesta aiheutuvat riskit ovat erittäin merkittäviä. Työn tavoitteena oli tutustua onnettomuustapauksiin, teräsrakenteista annettuihin viranomaismääräyksiin sekä ohjeisiin ja esittää laadunvarmistustoimenpiteitä, joiden avulla voidaan varmistua hitsaustyön riittävästä laadusta teräsrakentamisessa. Näitä laadunvarmistustoimenpiteitä ovat mm. hitsaushenkilöstön pätevöinti, hitsausohjeiden käyttäminen, ainetta rikkomattomat tarkastukset ja rakennesuunnitelmien tarkastukset. Toisena tavoitteena oli kartoittaa rakenteiden valmistajien ja pääurakoitsijoiden nykyistä tilannetta laadunvarmistuksen osalta sekä selvittää kiinnostusta kolmannen osapuolen tarjoamiin laadunvarmistuspalveluihin. Kyselyiden perusteella laadunvarmistuspalveluille on olemassa kysyntää tietyin kustannuksiin liittyvin varauksin. Palveluista eniten kiinnostusta herättivät ainetta rikkomattomat tarkastukset ja rakennesuunnitelmien tarkastukset.
Resumo:
This dissertation considers the segmental durations of speech from the viewpoint of speech technology, especially speech synthesis. The idea is that better models of segmental durations lead to higher naturalness and better intelligibility. These features are the key factors for better usability and generality of synthesized speech technology. Even though the studies are based on a Finnish corpus the approaches apply to all other languages as well. This is possibly due to the fact that most of the studies included in this dissertation are about universal effects taking place on utterance boundaries. Also the methods invented and used here are suitable for any other study of another language. This study is based on two corpora of news reading speech and sentences read aloud. The other corpus is read aloud by a 39-year-old male, whilst the other consists of several speakers in various situations. The use of two corpora is twofold: it involves a comparison of the corpora and a broader view on the matters of interest. The dissertation begins with an overview to the phonemes and the quantity system in the Finnish language. Especially, we are covering the intrinsic durations of phonemes and phoneme categories, as well as the difference of duration between short and long phonemes. The phoneme categories are presented to facilitate the problem of variability of speech segments. In this dissertation we cover the boundary-adjacent effects on segmental durations. In initial positions of utterances we find that there seems to be initial shortening in Finnish, but the result depends on the level of detail and on the individual phoneme. On the phoneme level we find that the shortening or lengthening only affects the very first ones at the beginning of an utterance. However, on average, the effect seems to shorten the whole first word on the word level. We establish the effect of final lengthening in Finnish. The effect in Finnish has been an open question for a long time, whilst Finnish has been the last missing piece for it to be a universal phenomenon. Final lengthening is studied from various angles and it is also shown that it is not a mere effect of prominence or an effect of speech corpus with high inter- and intra-speaker variation. The effect of final lengthening seems to extend from the final to the penultimate word. On a phoneme level it reaches a much wider area than the initial effect. We also present a normalization method suitable for corpus studies on segmental durations. The method uses an utterance-level normalization approach to capture the pattern of segmental durations within each utterance. This prevents the impact of various problematic variations within the corpora. The normalization is used in a study on final lengthening to show that the results on the effect are not caused by variation in the material. The dissertation shows an implementation and prowess of speech synthesis on a mobile platform. We find that the rule-based method of speech synthesis is a real-time software solution, but the signal generation process slows down the system beyond real time. Future aspects of speech synthesis on limited platforms are discussed. The dissertation considers ethical issues on the development of speech technology. The main focus is on the development of speech synthesis with high naturalness, but the problems and solutions are applicable to any other speech technology approaches.