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In this thesis we investigate the mathematical modeling of cognition using sensorimotor transition systems. The focus of the thesis is enactivism, where an agent learns to think through actions. As a theoretical basis for our implementation, we discuss a mathematical model of enactivist cognition, sensorimotor interaction and how they can be used as algorithmic aides for studying theoretical problems in robotic systems. In Chapter 3 of this thesis, we introduce a platform which was developed in the University of Oulu as a software project and explain how enactivism and sensorimotor interaction have been taken advantage of, in developing a 2D platform. This platform enables one to concretely implement and explore different interaction strategies that allow an agent to construct internal models of its surroundings. The agent in the platform is a multi-jointed robotic arm, which maneuvers through an obstacle-filled environment. The robotic arm tries to explore its environment with minimal sensory feedback, using algorithms created by the user of the platform. Our main goal on this thesis is to implement new features to this platform. We implement a memory functionality which allows the robotic arm to store all its performed actions. The memory helps the agent infer to a greater extent its surroundings from a limited sequence of action-observation pairs, and helps it in getting a better grasp of the environment. In addition, we implement other methods and functionalities, such as an obstacle sensor, a graph visualization of the internal models, etc. to enhance the perceptual ability of the robotic arm. In Section 5, we develop an algorithm for a simple 2D environment with no obstacles. Here the robotic arm makes a 360-degree move in four steps to perceive its surroundings and generates a state machine graph to visualize its internal model of the environment. The goal of the algorithm is to build an accurate representation of the environment with the help of memory. Through this algorithm we are able to evaluate the performance of the newly implemented features. We also test the platform through unit testing for finding and resolving bugs.Sensorimotoriset vuorovaikutusstrategiat robotiikassa. Tiivistelmä. Tässä tutkielmassa tutkimme kognition matemaattista mallintamista käyttämällä sensorimotorisia transitio-järjestelmiä. Tutkielman keskiössä on enaktivismi, jossa agentti oppii ajattelemaan toiminnan kautta. Teoreettisena perustana toteutuksellemme käsittelemme matemaattista mallia enaktivistisesta kognitiosta, sensorimotorista vuorovaikutusta ja kuinka niitä voidaan käyttää algoritmien apuvälineinä teoreettisten ongelmien tutkimisessa robottiikkajärjestelmissä. Tutkielman luvussa 3 esittelemme alustan, joka on kehitetty Oulun yliopistossa ohjelmistoprojektina, ja selittämme miten enaktivismia ja sensomotorista vuorovaikutusta on hyödynnetty 2D-alustan kehittämisessä. Alusta mahdollistaa erilaisten vuorovaikutusstrategioiden konkreettisen toteuttamisen ja tutkimisen. Näiden avulla agentti rakentaa sisäisiä malleja ympäristöstään. Alustassa mallinnettu agentti on moninivelinen robottikäsi, joka liikkuu esteitä sisältävässä ympäristössä. Robottikäsi pyrkii tutkimaan ympäristöään minimaalisen sensoritiedon avulla käyttämällä alustan käyttäjän luomia algoritmeja. Tutkielmamme päätavoite on kehittää uusia ominaisuuksia tälle alustalle. Toteutamme muistitoiminnallisuuden, jonka avulla robottikäsi tallentaa kaikki suoritetut toiminnot. Muisti auttaa agenttia päättelemään enemmän ympäristöstään rajoitettujen toiminta-havainto-parien avulla, ja auttaa sitä ympäristön hahmottamisessa. Lisäksi kehitämme muita menetelmiä ja toiminnallisuuksia kuten estesensorin ja sisäisten mallien graafisen visualisoinnin parantaaksemme robottikäden havainnointikykyä. Tutkielman myöhemmässä osassa kehitämme algoritmin yksinkertaiselle 2D-ympäristölle ilman esteitä. Siinä robottikäsi tekee 360 asteen liikkeen neljässä vaiheessa havainnoidakseen ympäristönsä, ja luo tilasiirtymäkaavion visualisoidakseen sisäisen mallinsa ympäristöstä. Algoritmin tavoitteena on rakentaa tarkka malli ympäristöstä muistin avulla. Tämän algoritmin avulla pystymme arvioimaan kehittämiemme uusien ominaisuuksien toimintaa. Testaamme alustaa myös yksikkötesteillä löytääksemme ja korjataksemme virheitä.

Wetlands are an integral part of the watershed ecosystems, and consists of shallow water. These wetlands contain high levels of nutrients and primary productivity which is ideal for the development of organisms that form the base of the food web and feed many species of fish, amphibians, shellfish, and insects. At the same time, due to extensive use and exploited by mankind civilization, heavy mental pollution has an important impact on wetland ecosystems. Heavy metals are released into the environment from a variety of natural and anthropogenic sources. Assessing heavy metals concentration in wetland sediments, their distribution, sources and potential ecological risk on aquatic organisms are crucial steps for the protection and sustainable utilization of wetland resources. Several studies have been performed on the distribution of heavy metal on wetland and the factor affecting the concentration and the risk caused by heavy metal pollution in aquatic ecosystems. This paper is primarily focused to provide a profound and brief review on present status of heavy metal contamination, their source, assessment and their impacts through sedimentary analysis.

Background: Immune checkpoint inhibitors (ICI) improve overall survival (OS) in patients with locally advanced, unresectable, or metastatic urothelial carcinoma (aUC), but response rates can be modest. We compared outcomes between patients with and without prior intravesical Bacillus Calmette-Guerin (BCG), who received ICI for aUC, hypothesizing that prior intravesical BCG would be associated with worse outcomes. Patients and Methods: We performed a retrospective cohort study across 25 institutions in US and Europe. We compared observed response rate (ORR) using logistic regression; progression-free survival (PFS) and OS using Kaplan-Meier and Cox proportional hazards. Analyses were stratified by treatment line (first line/salvage) and included multivariable models adjusting for known prognostic factors. Results: A total of 1026 patients with aUC were identified; 614, 617, and 638 were included in ORR, OS, PFS analyses, respectively. Overall, 150 pts had history of prior intravesical BCG treatment. ORR to ICI was similar between those with and without prior intravesical BCG exposure in both first line and salvage settings (adjusted odds radios 0.55 [P= .08] and 1.65 [P= .12]). OS (adjusted hazard ratios 1.05 [P= .79] and 1.13 [P= .49]) and PFS (adjusted hazard ratios 1.12 [P= .55] and 0.87 [P= .39]) were similar between those with and without intravesical BCG exposure in first line and salvage settings. Conclusion: Prior intravesical BCG was not associated with differences in response and survival in patients with aUC treated with ICI. Limitations include retrospective nature, lack of randomization, presence of selection and confounding biases. This study provides important preliminary data that prior intravesical BCG exposure may not impact ICI efficacy in aUC. © 2021

Free entry and exit from an industry is one of the indicators of competitive behaviour of that industry. It is alleged that exit from Bangladesh's poultry industry is high. Based on a survey of exited firms, nature and causes of exit were analysed and their implications for policy for the industry suggested.

Since the early 1990s, contract farming as a market institution in the poultry industry in Bangladesh has evolved along with the expansion of commercial poultry farming. Apart from classical contract farming within vertically integrated enterprises, there are also formal and informal contract arrangements in input marketing and output marketing. In this paper, characteristics of these forms of contract arrangements and their implications for the poultry industry in Bangladesh are discussed. A high drop-out rate among commercial poultry producers is observed. Results of a survey conducted among farmers who dropped out of the poultry business in recent years are presented, highlighting the causes of dropping out and the possible role of contract farming in addressing them.

This siudti- is concerned with the estimation of technical efficiency of the hatchery operators producing fish seed Using 56 samples comprising 15 from Jessore, 10 from Chandpur, 16 from Bogra, and 15 from Siymensingh districts, the study has used frontier 4.1 Package to estimate the technical efficiency of the hatchery operators. A Cobb-Douglas type production function with nine quantitative variables namely. pond area, human labour, feed, fertilizer, number of brood fish, number of times brood used in a year, fuel electricity and hormone dose given to female brood and a dummy for stochastic frontier and a linear technical inefficiency function with 4 variables: Age, Education, Experience and Training received by the hatchery operator were estimated. Several hypotheses tests were performed using Log-likelihood Ratio Test. The mean technical efficiency of the hatchery operators was 60 percent. Technical efficiency were not found to be skewed towards higher or lower scores. rather concentrated in the 30'h, 40`", 60"' and 90°i percentiles. Hypothesis of existence of inefficiency effect was rejected establishing that significant inefficiency exists. More than one third of the seed production potential remains unutilized. Utilizing the unexploited production potential of the fish seed producers rather than establishing new farms and hatcheries appears to be the pertinent policy. Training of the farm hatchery operators can help achieve the unexploited potential.

The study was undertaken to evaluate the economic and financial profitability of aromatic and fine rice production, using both primary and secondary data. Forty farmers who cultivated both Kataribhog and Chinigura, and fifteen farmers each producing Pajam and Nizershail were selected from Dinajpur district. For the Kalijira variety, thirty farmers were selected from Sherpur district. Among the aromatic and fine rice varieties Pajam had the maximum per hectare yield. But net returns per hectare for the aromatic varieties were higher due to the higher market prices and less production cost of the varieties. Domestic Resource Cost (DRC) ratios showed that Bangladesh had comparative advantage in the production of aromatic and fine rice both from the point of view of export and import substitution, except the Nizershail variety which was marginally unprofitable under export proposition. The study also identified some problems faced by the farmers in producing aromatic and fine rice. Finally, some policy guidelines were suggested.

An attempt was made in this study to appraise the investment proposition in dairying, incorporating the cash support incentive initiated by the government in recent years. Financial analysis was performed using primary data collected from different locations of Tangail district. The results indicated that dairy farming with both local and cross-bred cows was highly profitable. The profitability with cross-bred cows was more than that with local cows. Both the categories of farms had high benefit-cost ratios at 14 percent discount rate. The internal rate of return of more than 24 percent indicated that return from investment in dairying would be far more than the opportunity cost of capital in the formal capital market.

Relative performance of individual enterprises within each component of Crop-Cattle-Poultry Fish farming system was ascertained through gross margin analysis and the success of whole farm business was examined by applying residual income measures such as net farm income and management income. The results showed that gross margin per Taka of variable cost varied sufficiently among enterprises. Among the individual enterprises within the crop component, brinjal (summer) gave highest gross margin per Taka of variable cost. Among the components of the whole farm business, fish had the highest gross margin per Taka of variable cost. Net farm income was reasonably high and the system earned positive management income, indicating that the farms were economically viable even under all possible full cost considerations.

This study is an attempt to generate some micro level information in respect of pattern of consumption of selected food items and the related food consumption parameters. The results showed that rural consumers consumed more rice and non-food items. Per capita consumption of food in general increased substantially with rise in per capita income. The difference between the poor and the rich in terms of nutrition intake was wider in urban than in rural area. The findings also revealed that the quantities consumed or expenditure on food-rain, potato and pulses did not increase much with rising income in both the areas. On the other hand. chances in income were found to have more impact on consumption of other commodities.

Optimum cropping plan has been developed using data from a sample of 40 farms in a farming system research area of Mymensingh district. The results revealed a considerable divergence between the existing and optimal crop plans under both restricted and unrestricted capital situation. Among the crops incorporated in the optimal plan under restricted capital, Aman (LV) found the prime place in the Kharif-II land under non-irrigated situation, accounting for 33 per cent of the total cropped area. When capital restriction was relaxed, brinjal (summer) was the most dominant crop occupying 39 per cent of total cropped area. The optimal return with unrestricted capital was 49 per cent higher than the existing return from the crop enterprises. The results imply that serious efforts need to be directed to remove credit constraints for improving farm incomes of the typical farms studied in the area.

Food-specific and total calorie intake functions were estimated with respect to six selected food items - rice, wheat, potato, pulses, fish and edible oil- using the 1981-82 Bangladesh Household Expenditure Survey data. All the food-specific calorie price coefficients had expected sign except for pulses in the case of urban households. While calories from all other food items were normal goods, those from wheat were inferior goods for all the classes of households. Rice price had greater impact on total calorie intake for urban than for rural households. The income elasticity of demand for total calorie was higher for rural than for urban households. An account of quality preference revealed that people would substitute high-cost for low-cost-calorie foods with rising income even at the lower level income.

Food consumption parameters have been estimated for six selected food items-rice, wheat, potatoes, pulses, fish and edible oil-using the Bangladesh 1981-82 Household Expenditure Survey data. For the two major staples rice and wheat, the estimates revealed that while the absolute value of the own-price elasticity for rice of the rural households was twice that of the urban households, the absolute value of that for wheat of the urban households was more than four times that of the rural households. For most of the food items, rural and urban parameters were structurally different. However, estimates by disaggregated income classes revealed that the source of the difference between rural and urban parameters was the high-income households and for the low-income households, the implications of relative price and/or income changes on food consumption remained invariant with respect to their rural-urban locations. In interpreting tne relatively higher values of the parameter estimates of the rural households, the possible bias arising from consumption of own-production needs to be taken Into account.

This paper examines the level and composition of food availability, the role of public food distribution system (PFDS) in modifying the availability and consumption, and assesses the adequacy of overall consumption in relation to nutritional requirement. The PFDS appears to be increasingly assisting some special categories who are either urban or urban-like rural residents. While average per capita food and calorie intakes are declining. the existing level of per capita consumption seems to be consistent with defined calorie intake norm. However, distribution of food and calorie intake reveals widespread undernutrition in the vast segment of the population. Policies aiming to alleviate undernutrition should be commodity and target group specific and would have to be based on proper understanding of the food preference patterns of the classes of people.

This paper examines the relative efficiency of the alternative forms of land tenure in irrigated boro rice production with a sample of 124 farms. Inter-tenure comparison revealed that there were no major differences in resource use and yield among the specified tenure groups. However, owner-tenant farms obtained highest yield, gross and net return per acre while yield of crop, gross and net return per acre were lowest for the pure tenant farms. Comparative analysis of the owned and rented components of the same owner-tenant farms revealed that they used more of all the inputs and obtained higher yield on owned land than on rented land. Thus the evidence lend support to the Marshallian proposition that share tenancy results in under-utilization of resources and hence is an inefficient form of tenure arrangement.

The field performance of a rural poultry development project in Mymensingh has been examined through analysis of survey data collected from 124 poultry keepers. There has been marked improvement iin both meat and egg production in the selected areas covered by the project. Such results have been obtained by crossing local hens with exotic cocks and reducing mortality by ensuring proper veterinary services. Some lapses in the functioning of the project in terms of feeding, and vaccination were recorded and remedial measures suggested.