Improving the Potentials of Logistics Processes: Identification and Solutions

The importance of logistics for companies is a well known and justified issue. Today, enterprises are developing their logistics processes in order to match their products and services to the requirements of the most important customers. Therefore there is a need for developing analysing tools for logistics and especially for analysing the significance of various customer service elements. The aim of this paper is to propose analytic tools for supporting strategic level logistics decision making by emphasizing service level elements on two levels: (1) to introduce and propose approaches to categorize the developing efforts of logistics and (2) to introduce and/or propose approaches for solving some customer service related strategic level logistics problems. This study consists of two parts. In the first part an overview of the work is presented, and the second part comprises eight research papers on the topic of the study. The overview includes an introduction, where strategic and tactical level logistics problems are discussed and the relation of logistics to marketing and customer service issues is presented. In the first part of the study the objectives, the structure, the research strategy and the contribution of the research are described, and the challenges for future research are discussed. In the second part the three first papers deal with the identification of objectives for logistics while the remaining five papaers concentrate on solving customer service related strategic level logistics problems.

Chelating Adsorbents in Purification of Hydrometallurgical Solutions

In this thesis, equilibrium and dynamic sorption properties of weakly basic chelating adsorbents were studied to explain removal of copper, nickel from a concentrated zinc sulfate solution in a hydrometallurgical process. Silica-supported chelating composites containing either branched poly(ethyleneimine) (BPEI) or 2-(aminomethyl)pyridine (AMP) as a functional group were used. The adsorbents are commercially available from Purity Systems Inc, USA as WP-1® and CuWRAM®, respectively. The fundamental interactions between the adsorbents, sulfuric acid and metal sulfates were studied in detail and the results were used to find the best conditions for removal of copper and nickel from an authentic ZnSO4 process solution. In particular, the effect of acid concentration and temperature on the separation efficiency was considered. Both experimental and modeling aspectswere covered in all cases. Metal sorption is considerably affected by the chemical properties of the studied adsorbents and by the separation conditions. In the case of WP-1, acid affinity is so high that column separation of copper, nickel and zinc has to be done using the adsorbent in base-form. On the other hand, the basicity of CuWRAM is significantly lower and protonated adsorbent can be used. Increasing temperature decreases the basicity and the metals affinity of both adsorbents, but the uptake capacities remain practically unchanged. Moreover, increasing temperature substantially enhances intra-particle mass transport and decreases viscosities thus allowing significantly higher feed flow rates in the fixed-bed separation. The copper selectivity of both adsorbents is very high even in the presence of a 250-fold excess of zinc. However, because of the basicity of WP-1, metal precipitation is a serious problem and therefore only CuWRAM is suitable for the practical industrial application. The optimum temperature for copper removal appears to be around 60 oC and an alternative solution purification method is proposed. The Ni/Zn selectivity of both WP-1 and CuWRAM is insufficient for removal of the very small amounts of nickel present in the concentrated ZnSO4 solution.

Managing the Pricing of Integrated Solutions in Export Partnerships

Little research has been conducted to guide the management of marketing variables, such as pricing, in systems business context. Furthermore, given that international partnering has become a popular mode of operation for SMEs, the objective of the current thesis was to explore the scantly researched topic of managing the pricing of integrated solutions in an export partnership. Specifically, the thesis synthesizes literature findings from the three areas of export pricing, systems business, and export partnerships. The empirical section of the study consists of a qualitative single-case study of a Finnish systems integrator that has recently launched its export operations. Primary data was collected by conducting four interviews of the case company’s managers and by organizing one group interview session. The study findings indicate that a systems integrator’s pricing strategy in an export partnership can be very multidimensional and dependant on international pricing environment and partner characteristics, that an export partnership appears to have unique implications on a systems integrator’s pricing process, and that customer value –based pricing strategies might be particularly suited to pricing integrated solutions.

Novel Robot Solutions for Carrying out Field Joint Welding and Machining in the Assembly of the Vacuum Vessel of ITER

It is necessary to use highly specialized robots in ITER (International Thermonuclear Experimental Reactor) both in the manufacturing and maintenance of the reactor due to a demanding environment. The sectors of the ITER vacuum vessel (VV) require more stringent tolerances than normally expected for the size of the structure involved. VV consists of nine sectors that are to be welded together. The vacuum vessel has a toroidal chamber structure. The task of the designed robot is to carry the welding apparatus along a path with a stringent tolerance during the assembly operation. In addition to the initial vacuum vessel assembly, after a limited running period, sectors need to be replaced for repair. Mechanisms with closed-loop kinematic chains are used in the design of robots in this work. One version is a purely parallel manipulator and another is a hybrid manipulator where the parallel and serial structures are combined. Traditional industrial robots that generally have the links actuated in series are inherently not very rigid and have poor dynamic performance in high speed and high dynamic loading conditions. Compared with open chain manipulators, parallel manipulators have high stiffness, high accuracy and a high force/torque capacity in a reduced workspace. Parallel manipulators have a mechanical architecture where all of the links are connected to the base and to the end-effector of the robot. The purpose of this thesis is to develop special parallel robots for the assembly, machining and repairing of the VV of the ITER. The process of the assembly and machining of the vacuum vessel needs a special robot. By studying the structure of the vacuum vessel, two novel parallel robots were designed and built; they have six and ten degrees of freedom driven by hydraulic cylinders and electrical servo motors. Kinematic models for the proposed robots were defined and two prototypes built. Experiments for machine cutting and laser welding with the 6-DOF robot were carried out. It was demonstrated that the parallel robots are capable of holding all necessary machining tools and welding end-effectors in all positions accurately and stably inside the vacuum vessel sector. The kinematic models appeared to be complex especially in the case of the 10-DOF robot because of its redundant structure. Multibody dynamics simulations were carried out, ensuring sufficient stiffness during the robot motion. The entire design and testing processes of the robots appeared to be complex tasks due to the high specialization of the manufacturing technology needed in the ITER reactor, while the results demonstrate the applicability of the proposed solutions quite well. The results offer not only devices but also a methodology for the assembly and repair of ITER by means of parallel robots.

Separation of Gas Bubbles from Circulation Waters and Pulp Suspensions in Open Channel Flow

The objective of this thesis was to study the removal of gases from paper mill circulation waters experimentally and to provide data for CFD modeling. Flow and bubble size measurements were carried out in a laboratory scale open gas separation channel. Particle Image Velocimetry (PIV) technique was used to measure the gas and liquid flow fields, while bubble size measurements were conducted using digital imaging technique with back light illumination. Samples of paper machine waters as well as a model solution were used for the experiments. The PIV results show that the gas bubbles near the feed position have the tendency to escape from the circulation channel at a faster rate than those bubbles which are further away from the feed position. This was due to an increased rate of bubble coalescence as a result of the relatively larger bubbles near the feed position. Moreover, a close similarity between the measured slip velocities of the paper mill waters and that of literature values was obtained. It was found that due to dilution of paper mill waters, the observed average bubble size was considerably large as compared to the average bubble sizes in real industrial pulp suspension and circulation waters. Among the studied solutions, the model solution has the highest average drag coefficient value due to its relatively high viscosity. The results were compared to a 2D steady sate CFD simulation model. A standard Euler-Euler k-ε turbulence model was used in the simulations. The channel free surface was modeled as a degassing boundary. From the drag models used in the simulations, the Grace drag model gave velocity fields closest to the experimental values. In general, the results obtained from experiments and CFD simulations are in good qualitative agreement.

Mobile Teleoperation of a Mobile Robot

This thesis describes the design and implementation of a graphical application on a mobile device to teleoperate a mobile robot. The department of information technology in Lappeenranta University conducts research in robotics, and the main motivation was to extend the available teleoperation applications for mobile devices. The challenge was to port existing robot software library onto an embedded device platform, then develop a suitable user interface application that provides sufficient functionality to perform teleoperation tasks over a wireless communication network. This thesis involved investigating previous teleoperation applications and conducted similar experiments to test and evaluate the designed application for functional activity and measure performance on a mobile device which have been identified and achieved. The implemented solution offered good results for navigation purposes particularly for teleoperating a visible robot and suggests solutions for exploration when no environment map for the operator is present.

Adsorptive removal of harmful organic compound from aqueous solutions

Adsorption is one of the most commonly used methods in water treatment processes. It is attractive due to it easy operation and the availability of a wide variety of commercial adsorbents. This doctoral thesis focuses on investigating and explaining the influence of external phase conditions (temperature, pH, ionic strength, acidity, presence of cosolutes) on adsorption phenomena. In order to cover a wide range of factors and phenomena, case studies were chosen from various fields where adsorption is applied. These include the adsorptive removal of surface active agents (used in cleaning chemicals, for example) from aqueous effluents, the removal of hormones (estradiol) from drinking water, and the adsorption of antibiotics onto silica. The latter can beused to predict the diffusion of antibiotics in the aquatic system if they are released into the environment. Also the adsorption of living cells on functionalized polymers to purify infected water streams was studied. In addition to these examples, the adsorptive separation of harmful compounds from internal water streams within a chemical process was investigated. The model system was removal of fermentation inhibitors from lignocelluloses hydrolyzates. The detoxification of the fermentation broth is an important step in the manufacture of bioethanol from wood, but has not been studied previously in connection with concentrated acid hydrolyzates. New knowledge on adsorption phenomena was generated for all of the applications investigated. In most cases, the results could be explained by combining classical theories for individual phenomena. As an example, it was demonstrated how liquid phase aggregation could explain abnormal-looking adsorption equilibrium data. In addition to the fundamental phenomena, also process performance was of interest. This aspect is often neglected in adsorption studies. It was demonstrated that adsorbents should not be selected for a target application based on their adsorption properties only, but regeneration of the spent adsorbent must be considered. It was found that using a suitable amount of organic co-solvent in the regeneration can significantly improve the productivity of the process.

Components of customer value in nurse call solutions

This study aimed to identify the value components of nurse call solutions. The value creation of such systems was analyzed by using a framework that was created based on the existing customer value literature. The empirical part of the study was conducted as a multiple-case study by using qualitative research methods. The data for the analysis was gathered through structured interviews in ten Finnish eldercare centers. The results indicate that a nurse call solution creates value for eldercare centers by increasing the safety of the residents, and by improving the efficiency of the staff while also providing cost savings.

Recovery of carboxylic acids from aqueous solutions

Carboxylic acids are commonly used organic acids and have many applications in industries producing food and pharmaceutical products, surfactants and detergents. Especially formic, acetic, propionic and butyric acid are important organic chemicals. These compounds can be found in many side streams and plant effluents. Recovery costs of carboxylic acids are high when they are removed from dilute solution. Conventional processes for the recovery of carboxylic acids from aqueous solutions are classical distillation or extractive distillation, azeotropic distillation or liquid-liquid extraction. The literature part of this Master’s of Science Thesis comprises possible extractants in liquid-liquid extraction of carboxylic acids from aqueous solutions and methods for their regeneration form the extract. The experimental part of this Thesis investigates liquid-liquid extraction of carboxylic acids from aqueous solutions. The aim of this work was to find a suitable extractant for liquid-liquid extraction and suitable process conditions to recover carboxylic acids from aqueous solutions. Also, back extraction of carboxylic acids and their thermal decomposition in relation to distillation of were. Experiments showed that there is more than one possible extractant for liquid-liquid extraction of carboxylic acids. Results also showed that it is possible to separate carboxylic acids and regenerate all the used extractants by vacuum distillation at suitable temperature.

EDTA- and DTPA-functionalized silica gel and chitosan adsorbents for the removal of heavy metals from aqueous solutions

Adsorbents functionalized with chelating agents are effective in removal of heavy metals from aqueous solutions. Important properties of such adsorbents are high binding affinity as well as regenerability. In this study, aminopolycarboxylic acid, EDTA and DTPA, were immobilized on the surface of silica gel, chitosan, and their hybrid materials to achieve chelating adsorbents for heavy metals such as Co(II), Ni(II), Cd(II), and Pb(II). New knowledge about the adsorption properties of EDTA- and DTPA-functionalizedadsorbents was obtained. Experimental work showed the effectiveness, regenerability, and stability of the studied adsorbents. Both advantages and disadvantages of the adsorbents were evaluated. For example, the EDTA-functionalized chitosan-silica hybrid materials combined the benefits of the silica gel and chitosan while at the same time diminishing their observed drawbacks. Modeling of adsorption kinetics and isotherms is an important step in design process. Therefore, several kinetic and isotherm models were introduced and applied in this work. Important aspects such as effect of error function, data range, initial guess values, and linearization were discussed and investigated. The selection of the most suitable model was conducted by comparing the experimental and simulated data as well as evaluating the correspondence between the theory behind the model and properties of the adsorbent. In addition, modeling of two-component data was conducted using various extended isotherms. Modeling results for both one- and twocomponent systems supported each other. Finally, application testing of EDTA- and DTPA-functionalized adsorbents was conducted. The most important result was the applicability of DTPA-functionalized silica gel and chitosan in the capturing of Co(II) from its aqueous EDTA-chelate. Moreover, these adsorbents were efficient in various solution matrices. In addition, separation of Ni(II) from Co(II) and Ni(II) and Pb(II) from Co(II) and Cd(II) was observed in two- and multimetal systems. Lastly, prior to their analysis, EDTA- and DTPA-functionalized silica gels were successfully used to preconcentrate metal ions from both pure and salty waters

Measuring Processes of a New Packaging Solutions with the Balanced Scorecard, case DigiCup

The aim of this study was to create a Balanced Scorecard to the DigiCup solution. The first goal was to create process descriptions to the few critical processes. The second goal was to define appropriate measurements, according to customer survey as well as following the Balanced Scorecard process description, to manage the critical success factors. The overall goal of this study was to create a performance measurement system for the solution which guides the operation towards continuous improvement. This study was conducted by using both qualitative and quantitative methods, and the analysis was done by using a case study method. The material was gathered from the current customers, the management and the employees using structured, semi-structured and open group and individual interviews. The current customers were divided into retailers and direct customers of the DigiCup solution. The questions which the customers were asked were related to the information about interviewee, company, business strategy, market, satisfaction survey and future requirements. The management defined the strategy and took part in specifying the perspectives, objectives and measurements to the Balanced Scorecard of the DigiCup solution. The employees participated into the choosing of the metrics. The material consisted from altogether sixteen interviews. At the beginning of the study the product development, the order-delivery as well as the printing processes was chosen to be the critical processes of the DigiCup solution. These processes were concentrated on already in the literature review while trying to find the characteristics of these processes as well as the critical success factors and the appropriate measurements, which could be utilized when creating the Balanced Scorecard to the DigiCup solution according to the customer survey. The appropriate perspectives, objectives and measurements were found to the DigiCup solution. The chosen measures works as a basis for the development of IT-reporting tool. As a conclusion it can be stated that when discussing a new business, where the objectives are changing according to which development’s phases the company is in, the measurement should be updated often enough.

Future revenue models: Transformation from textbooks to digital solutions in the educational publishing industry, Case Sanoma Learning

This study was conducted in order to learn how companies’ revenue models will be transformed due to the digitalisation of its products and processes. Because there is still only a limited number of researches focusing solely on revenue models, and particularly on the revenue model change caused by the changes at the business environment, the topic was initially approached through the business model concept, which organises the different value creating operations and resources at a company in order to create profitable revenue streams. This was used as the base for constructing the theoretical framework for this study, used to collect and analyse the information. The empirical section is based on a qualitative study approach and multiple-case analysis of companies operating in learning materials publishing industry. Their operations are compared with companies operating in other industries, which have undergone comparable transformation, in order to recognise either similarities or contrasts between the cases. The sources of evidence are a literature review to find the essential dimensions researched earlier, and interviews 29 of managers and executives at 17 organisations representing six industries. Based onto the earlier literature and the empirical findings of this study, the change of the revenue model is linked with the change of the other dimen-sions of the business model. When one dimension will be altered, as well the other should be adjusted accordingly. At the case companies the transformation is observed as the utilisation of several revenue models simultaneously and the revenue creation processes becoming more complex.

Algorithmic Solutions for Combinatorial Problems in Resource Management of Manufacturing Environments

This thesis studies the use of heuristic algorithms in a number of combinatorial problems that occur in various resource constrained environments. Such problems occur, for example, in manufacturing, where a restricted number of resources (tools, machines, feeder slots) are needed to perform some operations. Many of these problems turn out to be computationally intractable, and heuristic algorithms are used to provide efficient, yet sub-optimal solutions. The main goal of the present study is to build upon existing methods to create new heuristics that provide improved solutions for some of these problems. All of these problems occur in practice, and one of the motivations of our study was the request for improvements from industrial sources. We approach three different resource constrained problems. The first is the tool switching and loading problem, and occurs especially in the assembly of printed circuit boards. This problem has to be solved when an efficient, yet small primary storage is used to access resources (tools) from a less efficient (but unlimited) secondary storage area. We study various forms of the problem and provide improved heuristics for its solution. Second, the nozzle assignment problem is concerned with selecting a suitable set of vacuum nozzles for the arms of a robotic assembly machine. It turns out that this is a specialized formulation of the MINMAX resource allocation formulation of the apportionment problem and it can be solved efficiently and optimally. We construct an exact algorithm specialized for the nozzle selection and provide a proof of its optimality. Third, the problem of feeder assignment and component tape construction occurs when electronic components are inserted and certain component types cause tape movement delays that can significantly impact the efficiency of printed circuit board assembly. Here, careful selection of component slots in the feeder improves the tape movement speed. We provide a formal proof that this problem is of the same complexity as the turnpike problem (a well studied geometric optimization problem), and provide a heuristic algorithm for this problem.

Feasibility study of the available relay protection solutions for microgrids

Thesis talks about relay protection for microgrids. Microgrid operation sets more challenges than traditional utility grid protection because of lower fault current levels. Solutions for these challenges are discussed in this paper. Thesis also studies available relay protection solutions and figures out how they would fit for microgrid protection.