Šio magistrinio darbo tikslas yra teoriškai ir praktiškai išnagrinėti kaip ir kokius žinomus užklausų srautų aptarnavimo sprendimo būdus galima realizuoti JAVA programavimo kalbos priemonėmis. Darbo metu iškeltus uždavinius sudaro konkurentiškumą valdančių modelių išnagrinėjimas, jų realizavimo JAVA programavimo kalbos priemonėmis analizė, realiai veikiančių komponentų sumodeliavimas ir sukūrimas, sukurtų konkurentiškumą valdančių komponentų tyrimas, išvadų bei rekomendacijų pateikimas siekiant perteikti darbo metu įgytas žinias kaip galima parametrizuoti užklausų srautų aptarnavimo komponentą užtikrinant optimalų išteklių panaudojimo, pralaidumo bei uždelsimo balansą. Darbo metu buvo nagrinėjami dviejų tipų konkurentiškumą valdantys modeliai, t.y. gijos pagrindu bei du įvykių išskyrimo ir reagavimo pagrindu realizuoti modeliai, kur pastarieji du buvo suprojektuoti atsižvelgiant į Douglas Schmidto siūlomas reaktoriaus ir proaktoriaus projektavimo schemas. Išanalizavus JAVA programavimo kalbos galimybes, paaiškėjo, kad visus modelius galima kuo puikiausiai sumodeliuoti ir realizuoti panaudojant sinchroninį besiblokuojantį įvedimo ir išvedimo posistemį, sinchroninį nesiblokuojantį įvedimo ir išvedimo posistemį (NIO) ir asinchroninį įvedimo ir išvedimo posistemį (AIO4J). Minėtas aukščiau konkurentiškumą valdantis komponentas buvo realiai panaudotas ir išbandytas sukurtame supaprastintame HTTP serveryje, kaip komponentas atsakingas už ryšio užmezgimą bei užklausų apdorojimą... [toliau žr. visą tekstą] / The purpose of this master thesis is to analyze how many of known solutions for request stream handling can be implemented in JAVA programming language. Also, in addition to it, this master thesis analyzes the way those solutions can be implemented using JAVA programming language. There are defined tasks to investigate in the scope of this thesis, which include following: exploration of well known concurrency managing models; analysis of their implementation possibilities in JAVA by designing and creating real working components; their implementation workflow research under various stress loaded conditions and, finally, supply recommendations for optimal parameterization for mentioned component to gain the best possible balance of resource utilization, throughput and latency. There were analyzed basically two types of concurrency managing models in this work, i.e. thread based and two models based on event notification principle, designed using Douglas Schmidt reactor and proactor design patterns. During exploration of JAVA programming language possibilities to implement above mentioned models a special attention was paid to the new input/output system (NIO) which provides synchronous non-blocking input/output operations, whereas to process operations asynchronously there was explored asynchronous execution of input/output operations by using JAVA non-native external AIO4J library created by IBM corporation. In order to perform stress and performance benchmarks for created... [to full text]

Modern railway is a sophisticated system depending on consistency between all its elements. It is not only a self-explanatory component of nowadays-social wealth, however it is also one of environment polluters. What is an actual impact of the railways on the environment of our country, what are the problems and how they are solved? The present master’s study reviews the main law acts, regulating a management of environmental protection of AB “Lietuvos geležinkeliai” (Limited Liability Company “Lithuanian Railways”), a situation of the management of environmental protection, the main problems and perspectives. The objective of the present study is to consider and assess the impact of AB “Lietuvos geležinkeliai” on the environment, to analyse the management of environmental protection in the enterprise, to forecast the means to decrease negative impact or to avoid it, as well as to assess the reasons, impedimental to efficient activities of this process. In order to ensure efficiently observation of the environmental protection, rational use of natural resources, an efficient management apparatus, conditioning efficient observation of the environmental protection, as well as sufficient financing are necessary. Therefore, the analysis of the impact of economical-industrial activities on the environment was selected as the main focus of the present study. The master’s study is comprised of 3 parts. In the first one, there are described legal acts of the Republic of... [to full text]

Darbo tikslas - įvertinti kraujo donorų požiūrį į pakartotinę kraujo donorystę ir nustatyti priežastis, dėl kurių kraujo donorai nesiryžta pakartotiniam kraujo davimui. Darbo uždaviniai:1.Įvertinti atlygintinų ir neatlygintinų kraujo donorų požiūrį į kraujo donorystę ir nustatyti pirmo kraujo davimo motyvus. 2. Nustatyti priežastis, dėl kurių kraujo donorai nesiryžta pakartotiniam kraujo davimui atlygintinų ir neatlygintinų donorų tarpe. 3. Nustatyti ir palyginti atlygintinos ir neatlygintinos kraujo donacijos ekonominius kaštus. Tyrimo metodika. Tyrimas vykdytas 2012 m. kovo-balandžio mėnesiais viešojoje įstaigoje Nacionalinis kraujo centras. Telefoninės apklausos būdu, pagal sudarytą klausimyną, buvo apklausti 400 kraujo donorai, kurie po pirmo kraujo davimo neatvyko pakartotinam kraujo davimui praėjus vieneriems ir daugiau metų. Ekonominis kraujo donorystės vertinimas atliktas skaičiuojant ir vertinant 2011 m. kraujo donorystės ekonominius rodiklius. Statistinė gautų duomenų analizė atlikta naudojant “SPSS 17.0” statistinę programą. Ryšio stiprumas tarp kategorinių kintamųjų buvo tiriamas naudojant Kramerio V koreliacijos koeficientą, kartu tikrinant hipotezę apie jo lygybę nuliui (statistinį reikšmingumą). Požymių priklausomybei nustatyti skaičiuotas chi-kvadrato (χ2) kriterijus. Kai reikšmingumo lygmuo p<0,05, požymių skirtumas tiriamųjų grupėse laikytas statistiškai reikšmingu. REZULTATAI. Dažniau neatlygintinai pirmą kartą duoti kraujo buvo atvykę asmenys, turintys... [toliau žr. visą tekstą] / AIM OF THE STUDY: to evaluate blood donors‘ attitude to repeated blood donation and to determine the causes why blood donors refuse to repeat blood donation. OBJECTIVES: 1. To evaluate remunerated and non-remunerated blood donors‘ attitude to blood donation and determine the incentives for the first blood donation. 2. To determine the causes why blood donors refuse to repeat remunerated and non-remunerated blood donation. 3. To assess and compare the cost of remunerated and non-remunerated blood donation. RESEARCH. The research was conducted in March - April, 2012, at National Blood Center. There was prepared a questionnaire and 400 blood donors, who did not donate blood after one year or more after first donation, were asked to answer the questions by phone. The economic blood donation evaluation was carried out while calculating and analysing the data regarding blood donation from the year 2011. The statistical analysis of the data was conducted using “SPSS 17.0” statistical programme. Cramer‘s V correllation coefficient was used to determine the relationship between categorical variables, at the same time checking the zero hypothesis (statistical significance). In order to determine the dependence of variables, chi-square (χ2) criterion was calculated. The differences were judged to be statistically significant, when p<0.05. RESULTS. Individuals who had higher university education, were employed and received a monthly salary of more than 2,500 Lt, first time donated... [to full text]

Made available in DSpace on 2014-12-17T14:53:20Z (GMT). No. of bitstreams: 1 LeticiaBN_DISSERT.pdf: 3065696 bytes, checksum: e0a127a5db1f17422acdf7f26d0487d7 (MD5) Previous issue date: 2014-04-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Diante das mudan?as do mercado, as empresas passaram a considerar como de muita import?ncia revisar seus modelos de gest?o, no intuito de encontrar um sistema que avalie e d? informa??es confi?veis, por sua vez, a gest?o do conhecimento pode ser considerada como de grande valia para uma companhia. A presente Disserta??o de Mestrado tem como objetivo geral analisar a influ?ncia da gest?o do conhecimento nas companhias brasileiras com melhor governan?a corporativa no Investor Relations Global Rankings. Para isso, foram reunidos elementos que contemplaram a abordagem pesquisada. Foi realizada uma pesquisa bibliogr?fica e documental, com a finalidade de reunir os trabalhos e documentos relacionados com esta tem?tica, buscando atualizar os conceitos sobre a gest?o do conhecimento, a governan?a corporativa e o IR Global Rankings, al?m de ajudar a verificar at? que ponto a gest?o do conhecimento pode influenciar empresas a possu?rem uma melhor governan?a corporativa. Esta pesquisa classifica-se ainda por ser explorat?ria descritiva, pois proporciona maiores informa??es sobre um assunto, com levantamento de dados tipo survey, j? que esse m?todo pode ser caracterizado pela obten??o de dados ou informa??es sobre caracter?sticas, a??es ou opini?es, e uma abordagem quantitativa e qualitativa. A pesquisa investigou a tem?tica em seis grandes organiza??es brasileira classificadas entre as melhores do mundo no quesito governan?a corporativa, no ano de 2012. A coleta de dados foi feita por pesquisa documental e bibliogr?fica, atrav?s de contato presencial, virtual e via um question?rio semi-estruturado enviado por e-mail, gerando as informa??es necess?rias para as an?lises. Os dados provenientes do question?rio, al?m das analises embasadas pela fundamenta??o te?rica, tiveram dados tabulados com o auxilio do programa estat?stico Statistical Package for the Social Sciences (SPSS). Ao final do estudo, foi poss?vel identificar a import?ncia da gest?o do conhecimento como recurso para a gest?o empresarial, bem como fornecer mais informa??es sobre essa ferramenta para as empresas pesquisadas, e assim, ajud?-las a formular estrat?gias para continuarem satisfazendo seus clientes

A distrofia muscular de Duchenne (DMD) é uma doença de caráter hereditário recessivo ligado ao cromossomo X, que determina a ausência da distrofia, a responsável pela progressiva degenaração muscular observada no DMD. Embora não expresse o fenótipo, a camundongo mdx apresenta a ausência da distrofia e o mais comum modelo animal experimental para estudar as repercursões da DMD em muitos orgãos. Este estudo foi realizado na cartilagem do processo condilar da mandíbula de mdx, um importante sítio de crescimento craniofacial. Assim, o PC dos mdx de 4 (G1) e 10 (G2) semanas e dos respectivos controles (camundongos c57BL/10 mice) foram avaliados usando as técnicas de microscopia de luz (H.E, Picrosirius e Safranina-O) e de imunohistoquímica (IGF e IGF-IR). Em ambos os grupos, não houve diferença estatísticamente significante na área do PC e comparação aos controles. O número de e a área dos condrócitos, bem como, a quantidade de matriz extracelular (MEC) forma menores nos grupos mdx. A imunorreatividade para ambos, IGF-I e IGF-IR, proporcionalmente maiores nos grupos mdx. Os dados quantitativos e predominância do colágeno tipo I nos grupos mdx, sugere um processo precoce de envelhecimento na cartilagem do PC desses animais. / The duchenne muscular dystrophy (DMD) is a recessive hereditary disease linked to X-chromossome that determines teh dystrophin abstence, the responsible for progressive muscle degeneration observed in DMD. Although not exhibit the phenotype, the MDX mouse reveal abstence of dystrophin and is the most common experimental animal model for DMD studies in many organs. This study was performed in the articular cartilage of the mandibular condylar process (PC) of MDX, an important site of craniofacial growth. Thus the PC of MDX and respective controls (C57BL/10 mice) were evaluated at the ages of 4 (G1) and 10 (G2) weeks using ligth microscopy (H.E, Picrosirius e Safranin-O) and immunohistochemical (IGF-I e IGF-IR) tecniques. In both groups, there was no statistical significant difference in PC area of the mdx and the respective controls. The number and area of the chondrocytes, as well as the amout of extracellular matrix (MEC) were lower in MDX groups. The immunoreactivity for both, IGF-I and IGF-IR, were propostionally higher im MDX groups. The quantitative data and the predominance of collagen type i fibers in the MDX groups suggest a premature aging process of the PC in these animals.

Estudos têm demonstrado o potencial da terapia fotodinâmica antimicrobiana (aPDT) na inativação de diferentes células microbianas. No geral, são três as fases de crescimento dos microrganismos: fase lag, exponencial e estacionária. Os objetivos deste estudo foram avaliar a susceptibilidade de células de Candida albicans em diferentes fases de crescimento, submetidas à aPDT, associando azul de metileno (50 &mu;M) e luz de emissão vermelha (&lambda;= 660 nm) e investigar alterações morfológicas, mecânicas e bioquímicas, antes e depois da aPDT, por microscopia eletrônica de varredura, de força atômica e por espectroscopia no infravermelho por transformada de Fourier. Os resultados obtidos sugerem que, em parâmetros letais, células em fase estacionária de crescimento (48 h) são menos susceptíveis à aPDT, quando comparadas àquelas em fases lag (6 h) e ex-ponencial (24 h) de crescimento. Entretanto, em parâmetros subletais, células de 6 h e 48 h mostraram a mesma susceptibilidade à aPDT. Em sequência, os experimentos foram realizados em parâmetros considerados subletais para células crescidas por 6 e 48 h. A avaliação morfológica mostrou menor quantidade de matriz extracelular em células de 6 h comparada àquelas de 48 h. A espectroscopia de força atômica mostrou que células em fase lag perderam a rigidez após a aPDT, enquanto que células em fase estacionária mostraram comportamento in-verso. Ainda, células de 48 h diminuíram sua adesividade após a aPDT, enquanto que células de 6 h e 24 h tornaram-se mais adesivas. Os resultados bioquímicos revelaram que as diferenças mais significativas entre as células fúngicas de 6 h e 48 h ocorreram na região de DNA e carboidratos. A aPDT promoveu mais alterações bioquímicas na região de DNA e carboidratos em células de 6 h e em lipídios e ácidos graxos em células de 48 h. Nossos resultados indicam que a fase de crescimento celular desempenha papel importante no sítio de ação da aPDT em células de C. albicans. / Studies have demonstrated the potential of antimicrobial photodynamic therapy (aPDT) on the inactivation of different microbial cells. Overall, there are three phases of cell growth: lag phase, exponential phase and stationary phase. The objectives of this study were to evaluate the susceptibility of Candida albicans in different growth stages submitted to aPDT, with methylene blue (50&mu;M) and red light (&lambda; = 660 nm) and to investigate morphological, mechanical and biochemical changes before and after aPDT, by scanning electron microscopy, atomic force microscopy and by Fourier transform infrared spectroscopy. The results suggested that with lethal parameters, cells in stationary phase (48 h) are less susceptible to aPDT, compared to those in lag phase (6 h) and exponential phase (24 h). However, in sub-lethal parameters 6 h and 48 h cells showed the same susceptibility to aPDT. The following results were obtained in sub-lethal parameters. The morphological evaluation showed lower amount of extra-cellular matrix at 6 h compared to cells growth for 48 h. The atomic force spectroscopy showed that cells in lag phase lost cell wall rigidity after aPDT, while cells in stationary phase showed a reverse behavior. Furthermore, 48 h cells presented a decrease in their adhesiveness after aPDT, whereas cells growth for 6 h and 24 h become more adhesive. The biochemical evaluation showed that the most significant differences among the fungal cells growth for 6 h and 48 h in DNA and carbohydrates. The aPDT caused more expressive alterations on DNA and carbohydrates in cells growth for 6 h, while cells growth for 48 h presented significant alterations on lipids and fatty acids. Our results indicate that cell growth phase play an important role on the target sites affected by aPDT in C. albicans cells.

Différentes techniques spectroscopiques (impédancemétrie électrique, RMN, IR et Raman) ont été utilisées pour étudier la mobilité ionique de deux séries de verres binaires de borate d’alcalins (Li₂O-B₂O₃ et Na₂O-B₂O₃) dans une large gamme de composition en relation avec la structure, aussi bien dans l’état solide que dans l’état fondu. Nous avons ainsi établi un bilan complet de l’évolution de la structure du réseau vitreux à température ambiante en fonction de la teneur en oxyde d’alcalin M₂O. Alors que B₂O₃ n’est formé que d’unités BO₃, organisées en anneaux boroxol reliés par des chaînes, l’ajout d’alcalins entraîne l’apparition d’unités BO₄- incorporées dans différents groupements borate. Parallèlement, les chaînes et les boroxols disparaissent progressivement. A partir de 20% en M₂O, les alcalins commencent à jouer un rôle de modificateurs de réseau vitreux en cassant des liaisons, entrainant la formation d’oxygènes non-pontants (NBO). Leur proportion augmente rapidement de telle sorte qu’à partir de 40% de M₂O, la teneur en BO₄- rediminue. L’association de deux dispositifs de mesure de l’impédance complexe a permis d’obtenir des valeurs fiables de la conductivité sur un intervalle de température très étendu allant du solide jusqu’à l’état fondu. En dessous de Tg, la conductivité statique suit une loi d’Arrhenius. Sa valeur augmente avec la teneur en M₂O, toutefois, deux changements de régime sont observés : le premier vers 32% de M₂O coïncide avec l’anomalie de bore et peut être relié à la formation d’un nombre important de NBO, le second, est observé dans la série Na vers 10-20% de Na₂O et serait provoqué par une compaction du réseau. En passant à l’état fondu, la conductivité augmente de façon considérable et suit une loi VFT. Nous avons observé que l’anomalie de bore persiste à l’état fondu, mais se déplace vers les basses teneurs en M₂O. / Different spectroscopic techniques (electrical impedancemetry, NMR, IR and Raman) have been used to study ionic mobility of two series of binary alkaline borate glasses (Li₂O-B₂O3 and Na₂O-B₂O₃) in a wide range of composition in relation to their structure, both in the solid and molten state. We have thus established a complete description of the structural evolution of the vitreous network at ambient temperature as a function of the alkaline oxide M₂O content. While B₂O₃ is only formed of BO₃ units, organized in boroxol rings linked by chains, the alkaline addition leads to the appearance of BO₄- units incorporated in different borate groups. At the same time, chains and boroxols disappear gradually. From 20% M₂O, the alkalines start to play the role of vitreous network modifiers by breaking bonds, resulting in the formation of non-bridging oxygens (NBO). Their proportion increases rapidly so that, from 40% M₂O, the BO₄- content decreases. The association of two devices for measuring the complex impedance enabled us to obtain reliable values of the conductivity over a very extended temperature range from the solid to the molten state. Below Tg, the static conductivity follows Arrhenius law. Its value increases with the M₂O content, however, two changes are observed: the first towards 32% M₂O coincides with the so-called boron anomaly and can be related to the formation of a large number of NBO, the second, is observed in the Na series towards 10-20% Na₂O and is caused by network compaction. When passing to the molten state, the conductivity increases considerably and follows a VFT law. We observed that the boron anomaly persists in the molten state, but moves to lower M₂O contents.

During the continuous production of bread sometimes there are problems that lead to interruptions in the production and consequently to quality problems. One such problem is the bread burning in the contact area between the bread and the conveyor belt. In order to understand the problem and to know how to quantify it, it is necessary to understand what a thermodynamic system is and what types of systems exist, how the various types of heat transfer are processed, how to measure the temperature of an object by infrared radiation and some mathematical methods such as the least square root method. Temperature measurements were planned and carried out. The goal with the first experiment was to understand how the temperature of the conveyor belt varies during an interruption. All the other tests were done to investigate the effects of different solutions in the temperature variation of the belt. According to the results, the best solution is to turn off the oven during an interruption and the worst to spray the belt with water. To spray the belt with water may be a better solution than these results shows, but it is very affected by other problems, like depositions of limestone on the nozzles. A lot more solutions could be found but due to the time available, it was not possible to investigate all the variables/solutions in the process. A long-term  study would help understand much more within the regulation of the industrial baking process. / Under kontinuerlig produktion av bröd finns det ibland problem som leder till avbrott i produktionen och kvalitetsproblem. Ett sådant problem är att brödet blir bränt  i kontaktytan mellan brödet och transportbandet. För att förstå problemet och veta hur man kvantifierar detta,  är det nödvändigt att förstå vad ett termodynamiskt system är och vilka typer av system finns, hur olika typer av värmeöverföring sker, hur man mäter temperatur med hjälp av infraröd strålning och några matematiska metoder som minst kvadratrotsmetoden. Temperaturmätningar planerades och genomfördes. Målet med det första experimentet var att förstå hur transportbandets temperatur varierar under ett huppehåll. Alla andra tester utförades för att undersöka effekterna av de olika lösningarna i bandets temperaturvariation. Enligt resultaten är den bästa lösningen att stänga av ugnen under ett uppehåll och det värsta att spreya bältet med vatten. Att spreya bältet med vatten kan vara en bättre lösning än vad resultaten visar, men det påverkas mycket av andra problem, som avsättningar av kalksten på munstyckena. Många fler lösningar kunde hittas men det var inte möjligt att undersöka alla variabler / lösningar i processen på grund av tillgänglig tid. En långsiktig studie skulle hjälpa till att förstå mycket mer inom regleringen av industriell bakning.

Med den tekniska utvecklingen inom 3D-skanning det senaste decenniet har användningen av punkmolnsdata ökat signifikant. För att skapa dessa punkmoln används en mängd olika metoder och instrument. Bland annat används ofta fotogrammetri, terrester laserskanning eller mobil laserskanning. Med de nyare mobila skannrarna används oftast en SLAM-algoritm för att kunna korrekt skanna omgivningen samtidigt som skannern förflyttas. Till detta används oftast en IMU som positionerar skannern genom tröghetsnavigering eller kameror för att med triangulering bestämma positionen. Med nya förbättrade algoritmer och utrustning blir systemen hela tiden noggrannare och det utvecklas fler och fler nya system, ofta för specifika användningsområden. Matterport Pro2 3D-kamera som testades i detta projekt är ett sådant system som huvudsakligen utvecklats för att genom skanning, RGB-D och 360°- bilder visualisera och skapa digitala modeller av bostäder. Dessa modeller skapas både i form av punktmoln och meshmodeller. I projektet undersöks hur olika ljusförhållanden påverkar resultatet vid skapande av 3D-modeller med Matterport Pro2 kameran. Uppmätta längder mellan signaler utplacerade i testrummet användes för att kontrollera punktmolnen. Totalt skannades rummet fem gånger vid olika ljussättning varierande från 1 till 800 lux. Avvikelserna i längderna från punktmolnen jämfördes för att avgöra vilket punktmoln som avvek minst från de uppmätta längderna i rummet. Resultatet tyder på att bästa ljussättningen är runt 30 - 60 lux. Ingen skillnad i mätosäkerhet mellan övriga ljusnivåer kunde ses. Utöver det visar avvikelserna också tecken på påtagliga systematiskt fel vilket inte är helt oväntat och har påvisats av en tidigare studie av samma kamera. Detta betyder att kameran behöver kalibreras innan den används för skanning som kräver låg mätosäkerhet. / Due to the technological development within 3D-scanning the last decade usage of pointcloud data has increased significantly. To generate these pointclouds a plethora of methods and instrument are used. Among other photogrammetry, terrestrial laser scanning and mobile laser scanning are commonly used. With the newer mobile scanning systems a SLAM algorithm is usually used for the scanner to correctly scan the surroundings while being moved at the same time. To achieve this a IMU is usually used for positioning or cameras using triangulation. With new algorithms and equipment scanning systems keeps improving. This leads to more and more systems being developed, usually for a specific area of usage. Matterport Pro2 3D-camera which was tested in this project is such a system developed mainly for visualising and creating 3D-models of housing through scanning, RGB-D and 360°-images. These models generated are pointclouds aswell as meshmodels. In this project the effect of different illuminance has on the results when creating 3D-models with the Pro2 camera is tested. Measured distances between targets placed around the testing room were used for checking the point clouds for errors. In total five scans were performed at different illuminance varying from 1 – 800 lux. Deviations between measured distances and point cloud distances were compared to determine which point cloud deviated the least. Results show that an illuminance of about 30 - 60 lux gave the best result. Any significant differences between the other light conditions could not be determined. Furthermore, the results imply there is a systematic error which is not completely unexpected and has been shown in a previous study with the same camera. This means the camera needs a calibration before being used to scan where higher accuracy is needed.

The aim of the Diploma thesis is to consider an influence of soil management (rotation of crops on arable land and grassland) to quantity and quality of humic substances. These properties are depended not only upon way of soil management, but also upon climatic effects, such are rainfall, temperature, elevation above sea-level, level of underground water and content of clay. Significantly influenced factors are content and form of organic carbon which is very tightly bonded to humic substances. In this work the humic acids content and properties progression was studied in given time period. Also the effect of crop rotations to changes of physical and chemical properties of humic acids in soil environment was observed. Diploma thesis was realized in co-operation with Mendel University in Brno, which supplied elaborating samples. Studied soil samples were taken from humus horizon Cambisol modal Vatín during years 1999–2006, always in autumn. Individual samples were characterized by available analytical methods, which are generally used in humic substances research area. They are especially fluorescence spectrometry, UV-VIS and infrared spectrometry and acid-base and conductometric titrations.