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- arrayed waveguide gratings (11)
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Ausgehandeltes Verständnis
(2020)
Entscheidungen über die optimierte organisatorische Wertschöpfung werden oft von mehreren Personen getroffen. Möchte die entscheidungsorientierte BWL anwendungsorientiert sein, legt sie den Fokus auf das Gewebe von aufeinander verweisenden (entscheidungsfördernden) Kommunikationen zu legen und auf der Erkenntnisfigur des Beobachters aufzubauen.
Auslandssemester im Karrierefokus – Evaluierung der Auslandssemester am Beispiel einer Hochschule
(2015)
Ausrechnen oder aushandeln?
(2023)
Ausscheidungsmanagement
(2021)
Die vorliegende Studie untersucht die Auswirkungen der Covid-Pandemie auf die Finanzierungssituation von Unternehmen in Vorarlberg. Besonderes Augenmerk wird dabei auf kleine und mittlere Unternehmen sowie deren Eigenkapitalausstattung gelegt. Die Analyse erfolgt anhand einer quantitativen Befragung von 569 Unternehmen im Zeitraum Ende Oktober/Anfang November 2021. Ein Großteil der befragten Unternehmen schätzt die Finanzierungssituation insgesamt als befriedigend oder besser ein. Eigenkapital wird die höchste Relevanz aller Finanzierungsquellen zugesprochen. Obwohl 39% der befragten Unternehmen eine Eigenkapitalerhöhung für Ihr Unternehmen als nötig erachten, haben aktuell nur 14% Überlegungen in diese Richtung. Die Ergebnisse der Studie weisen darauf hin, dass eine Beseitigung der steuerlichen Bevorzugung von Fremdkapital (Debt Bias) einen relevanten Anreiz für Eigenkapitalerhöhungen liefern könnte.
The photonic integrated circuits are required in the next generations of coherent terabit optical communications. The software tools for automated adjustment and coupling of optical fiber arrays to photonic integrated circuits has been developed. The obtained results are needed in final production phase in the technology process of photonic integrated circuits packaging.
The usage of data gathered for Industry 4.0 and smart factory scenarios continues to be a problem for companies of all sizes. This is often the case because they aim to start with complicated and time-intensive Machine Learning scenarios. This work evaluates the Process Capability Analysis (PCA) as a pragmatic, easy and quick way of leveraging the gathered machine data from the production process. The area of application considered is injection molding. After describing all the required domain knowledge, the paper presents an approach for a continuous analysis of all parts produced. Applying PCA results in multiple key performance indicators that allow for fast and comprehensible process monitoring. The corresponding visualizations provide the quality department with a tool to efficiently choose where and when quality checks need to be performed. The presented case study indicates the benefit of analyzing whole process data instead of considering only selected production samples. The use of machine data enables additional insights to be drawn about process stability and the associated product quality.
Load shifting of resistive domestic hot water heaters has been done in Europe since the 1930s, primarily to ease the power supply during peak times. However, the pursued and already commenced energy transition in Europe changes the requirements for the underlying logic. In this more general context, demand side management is considered a viable approach to utilize the flexibility of thermal and electrochemical storage systems for buffering energy generated from renewables. In this work, an autonomous approach for demand side management of energy storage systems is developed, which is based on unidirectional communication of an incentive. This concept is then applied to the specific problem of resistive domestic hot water heaters.
The basic algorithms for an optimized operation are developed and evaluated based on simulation studies. The optimization problem considered, maps the search for the optimal heating schedule, while ensuring the temperature limits defined: Firstly, a maximum, which is defined by the hysteresis set point temperature; Secondly, during hot water draw offs, the outlet temperature should not fall below a set minimum. To establish this, the time series of hot water usage has to be predicted.
Depending on the complexity of the hot water heater model used, the formulation of the problem ranges from a linear to non-linear optimization with discontinuous constraints. The simulation studies presented, comprise a formulation as binary linear optimization problem, as well as a solution based on a heuristic direct method to solve the non-linear version. In contrast to the first linear approach, the latter takes stratification inside the tank into account. One-year simulations based on realistic hot water draw profiles are used to investigate the potentials with respect to load shift and energy efficiency improvements. Additional to assuming perfect prediction of user behavior, this work also considers the k-nearest neighbors algorithm to predict the time series. If compared to usual night-tariff switched operation, assuming perfect prediction shows 30 % savings on the electricity market when stratification is taken into account. The user prediction proposed leads to 16 % cost savings, while 6 % of the electric energy is conserved.
Based on the linear approach, a prototype is developed and used in a field test. A micro computer processes the sensor information for local data acquisition, receives electricity spot market prices up to 34 hours in advance, solves the optimization problem for this time horizon, and switches the power supply of the resistive heating element accordingly. Beside the temperature of the environment, the inlet and outlet temperatures, the temperature inside the tank is measured at five points, as well as the water volume flow rate and the electric power recorded. Two test runs of 18 days each, compare the night-tariff switched operation to the price-based optimization in a real-world environment. Results show a significant increase of 6 % in thermal efficiency during the operation based on the algorithm developed, which can be contributed to the optimization accounting for the usage expected.
To facilitate the technical and economic feasibility for retrofit-able implementations of the method proposed for autonomous demand side management, the sensors used must be kept to a minimum. A sufficiently accurate state estimation of the storage has to be achieved, to facilitate a useful model predictive control. Therefore, the last part of this work focuses on the aspect of automated system identification and state estimation of resistive domestic hot water heaters. To that end, real hot water usage profiles and schedules gathered in a field test are used in a lab setup, to collect data on the temperature distribution inside the tank during realistic operating conditions. Four different thermal models, common in literature, are considered for state estimation and system identification. Based on the data collected in the lab, they are evaluated with respect to robustness, computational costs, and estimation accuracy. Based on the observations made in the experiments, an extension of the one-node model by a single additional parameter is proposed. By this adaption, a linear temperature distribution in the lower part of the tank can be modeled during heating. The resulting model exhibits improved robustness and lower computational costs, when compared to the original model. At the same time, the average temperature in the storage tank is estimated nearly as accurate (6 % mean average percentage error) as in the case of the about 50 times more computationally expensive multi-layer model (4 % mean average percentage error).
Demand-side management approaches that exploit the temporal flexibility of electric vehicles have attracted much attention in recent years due to the increasing market penetration. These demand-side management measures contribute to alleviating the burden on the power system, especially in distribution grids where bottlenecks are more prevalent. Electric vehicles can be defined as an attractive asset for distribution system operators, which have the potential to provide grid services if properly managed. In this thesis, first, a systematic investigation is conducted for two typically employed demand-side management methods reported in the literature: A voltage droop control-based approach and a market-driven approach. Then a control scheme of decentralized autonomous demand side management for electric vehicle charging scheduling which relies on a unidirectionally communicated grid-induced signal is proposed. In all the topics considered, the implications on the distribution grid operation are evaluated using a set of time series load flow simulations performed for representative Austrian distribution grids. Droop control mechanisms are discussed for electric vehicle charging control which requires no communication. The method provides an economically viable solution at all penetrations if electric vehicles charge at low nominal power rates. However, with the current market trends in residential charging equipment especially in the European context where most of the charging equipment is designed for 11 kW charging, the technical feasibility of the method, in the long run, is debatable. As electricity demand strongly correlates with energy prices, a linear optimization algorithm is proposed to minimize charging costs, which uses next-day market prices as the grid-induced incentive function under the assumption of perfect user predictions. The constraints on the state of charge guarantee the energy required for driving is delivered without failure. An average energy cost saving of 30% is realized at all penetrations. Nevertheless, the avalanche effect due to simultaneous charging during low price periods introduces new power peaks exceeding those of uncontrolled charging. This obstructs the grid-friendly integration of electric vehicles.
The electricity demand due to the increasing number of EVs presents new challenges for the operation of the electricity network, especially for the distribution grids. The existing grid infrastructure may not be sufficient to meet the new demands imposed by the integration of EVs. Thus, EV charging may possibly lead to reliability and stability issues, especially during the peak demand periods. Demand side management (DSM) is a potential and promising approach for mitigation of the resulting impacts. In this work, we developed an autonomous DSM strategy for optimal charging of EVs to minimize the charging cost and we conducted a simulation study to evaluate the impacts to the grid operation. The proposed approach only requires a one way communicated incentive. Real profiles from an Austrian study on mobility behavior are used to simulate the usage of the EVs. Furthermore, real smart meter data are used to simulate the household base load profiles and a real low voltage grid topology is considered in the load flow simulation. Day-ahead electricity stock market prices are used as the incentive to drive the optimization. The results for the optimum charging strategy is determined and compared to uncontrolled EV charging. The results for the optimum charging strategy show a potential cost saving of about 30.8% compared to uncontrolled EV charging. Although autonomous DSM of EVs achieves a shift of load as pursued, distribution grid operation may be substantially affected by it. We show that in the case of real time price driven operation, voltage drops and elevated peak to average powers result from the coincident charging of vehicles during favourable time slots.
A new software tool, called AWG-Channel-Spacing, is developed to calculate accurate channel spacing of an arrayed waveguide gratings (AWG) optical multiplexer/demultiplexer. This tool has been developed with the application framework QT in the programming language C++. The tool was evaluated with a design of 20-channel 200 GHz AWG. The achieved simulated transmission characteristics prove the correct functionality of the tool.
By a simple femtosecond laser process, we fabricated metal-oxide/gold composite films for electrical and optical gas sensors. We designed a dripple wavelength AWG-spectrometer, matched to the plasma absorption wavelength region of the composite films. H2/CO absorptions fit well with the AWG design for multi gas detection sensor arrays
A new software tool, called AWG-Wuckler, is developed to calculate geometric parameters of arrayed waveguide grating structures for telecommunication and medical applications. These parameters are crucial for a AWG layout which will be created and simulated using commercial photonic design tools. The design process of AWG is very complex because its geometric dimensions depend on a large number of input design parameters and other input design parameters. Often geometric constraints require an adjustment of the input design parameters and vice versa. Calculation and adjustment of the geometric parameters is a time-consuming process that is currently not fully supported by any commercial photonic tool. AWG-Wuckler tool overcomes this issue and offers a fast and easy to use solution. The tool was already applied in various AWG designs and is technologically well proven.
Back to the future of gaming
(2014)
Besser entscheiden
(2021)
Unüberschaubar viele Vorschläge des systematischen Entscheidens führen bei bestimmten Rahmenbedingungen zum Erfolg. Die berufliche Praxis weicht aber zumeist stark davon ab, daher sind viele Methoden unbrauchbar. Wie kann man dennoch seine Fähigkeit zu Entscheiden verbessern? Man orientiert sich an grundlegenden Handlungsmaximen.
Beyond the Four-Level Model: Dark and Hot States in Quantum Dots Degrade Photonic Entanglement
(2023)
Entangled photon pairs are essential for a multitude of quantum photonic applications. To date, the best performing solid-state quantum emitters of entangled photons are semiconductor quantum dots operated around liquid-helium temperatures. To favor the widespread deployment of these sources, it is important to explore and understand their behavior at temperatures accessible with compact Stirling coolers. Here we study the polarization entanglement among photon pairs from the biexciton–exciton cascade in GaAs quantum dots at temperatures up to ∼65 K. We observe entanglement degradation accompanied by changes in decay dynamics, which we ascribe to thermal population and depopulation of hot and dark states in addition to the four levels relevant for photon pair generation. Detailed calculations considering the presence and characteristics of the additional states and phonon-assisted transitions support the interpretation. We expect these results to guide the optimization of quantum dots as sources of highly entangled photons at elevated temperatures.
Bilder als Affektgeneratoren
(2020)
Black titanium dioxide in situ generated on femtosecond laser induced periodic surface structures
(2018)
Blood and breath profiles of volatile organic compounds in patients with end-stage renal disease
(2014)
Brainstorming ist ein Mythos
(2021)
Bridges between families
(2016)
Shaolin Wu Fo Dao – die Synthese japanischer und chinesischer Kampfkunst-Lehre auf der Grundlage zen-buddhistischer Theorie und Praxis ist eine neu geschaffene Disziplin. In dieser Fusion verbinden sich wesentliche Elemente aus Budo und Shaolin (-Wudao), deren traditionellen Körper-Geist-Übungen von Kampftechnik (Bu/Wu) und Meditation (Zen/Chan) als originäre Weg- und Heilslehre (Do/Dao) seit jeher der Persönlichkeits- und spirituellen Entwicklung des Ausübenden dienten.
Hier nun, in der Überwindung alter Grenzen zwischen japanischer und chinesischer Kampfkunstsysteme („hart“ und „weich“), wurde hier nun erstmaligen ein zusammengewachsenes Kampfkunstsystem kreiert, um die beidseits positiven Wirkungen auf den Menschen zu bündeln und – und das ist das Besondere – sie in den Dienst buddhistischer (Butsu, jap.: Buddha / chin. Fo) Psychologie und Psychotherapie zu stellen.
Die Verbindung von Budo mit Shaolin als eigenständiges praktisches Lehrkonzept, allein schon eine „revolutionäre Innovation“, erfährt durch ihren Einsatz als spezielle Methode einer Heilkunst zusätzlich Pioniercharakter in der Behandlung von Leid. Gemeint sind sowohl Ansätze aus der Budopädagogik und speziellen Budotherapie zur Heilung, Linderung oder Prävention von physischen, psychosomatischen und psychischen Krisen, Störungen, Krankheiten, Behinderungen und Leiden, als auch im Sinne des philosophischen und wissenschaftlichen Buddhismus, „das Leid in der Welt zu mindern“, zum Wohle des Menschen, für sein Glück und Frieden zu arbeiten.
Budo als Oberbegriff für die traditionellen Kampfkünste, eigentlich namentlich Japans, aber hier im weiteren Sinne alle Kampf- und Bewegungskünste Asiens, die sich als Weg und nicht Sport begreifen, ist in den letzten Jahren vermehrt Gegenstand der öffentlichen Diskussion. Jüngere Veröffentlichungen zum Thema nehmen das historisch, philosophisch, psychologisch und pädagogisch Besondere und sich vom modernen Kampfsport gänzlich Unterscheidende in den Blick, ohne dass allerdings weiterhin begrifflich und inhaltlich falsche Vorstellungen durch die absurde Vereinnahmung der allein dem Budo zugeschrieben Wesenszüge und Wirkweisen in sog. "Budo-Sport"-Verbänden immer mehr verbreiten. Gerade so, als könne man dem modernen Kampfsport durch den Zusatz "Budo" (der suggerieren soll, man beziehe sich auf dessen Wesentliche, "Geistige") etwa einen ehrwürdig-traditionellen Charakter verleihen und den Wettkampfsport bereichern, gar ethisch aufwerten.
Insofern bedarf es immer noch oder immer mehr der Aufklärung darüber, was denn das eigentliche Wesen und Wirken von Budo überhaupt ausmacht, um dem Ganzen gerecht zu werden. Dabei soll sich dieses Buch nun weniger auf die historische, seit der Edo-Periode (1600-1868) vor allem vom Zen-Buddhismus (neben Konfuzianismus und Taoismus sowie Shaolin) geprägte Entwicklung von Budo aus den alten Kriegskünsten (Bugei und Bujutsu) eingehen, als auf das nunmehr auch heute noch Wesentliche und "Spezielle".
Budo als spirituelle wie praktisch-philosophische Weg-Lehre und dadurch Kampf-"Kunst" kann, recht verstanden, ein einzigartiger Schatz in der Theorie und Praxis des Studiums von "Kampf" und "Kämpfen-Können" sowie des Selbst sein, und am Ende auch des eigenen Lebens. Budo wirkt!
Es ist ein auf Bewegung, Begegnung und Besinnung angelegtes bewährtes ganzheitliches Instrument der Selbsterziehung, Charakterschulung und Persönlichkeitsentwicklung und als originärer Weg ("Do") zum "Friedvollen Krieger" eine konkrete Anleitung zu körperlicher, seelischer, geistiger, d.h. psycho-physischer wie psycho-emotionaler Selbstbeherrschung, die auf der Grundlage von stetig geübter Achtsamkeit und Wertschätzung in der Meisterschaft zu Einsicht und Gewaltverzicht führt. In diesem Buch wird das Thema Budo, sein Wesen und Wirken, aus Erfahrung und wissenschaftlicher Erkenntnis heraus analysiert, um ein ebenso weitergehendes wie tieferes Verständnis von der Sache zu fördern.
Die Autoren (Vorstellung im entsprechenden Kapitel hinten), allesamt!
Digitalization is changing business models and operational processes. At the same time, improved data availability and powerful analytical methods are influencing controlling and increasingly require the use of statistical and information technology skills and knowledge. Using a case study from marketing controlling, the article shows the use of business analytics methods and addresses the tasks of controlling in the digital age.
Die Digitalisierung verändert Geschäftsmodelle und betriebliche Prozesse. Zugleich beeinflussen auch eine verbesserte Datenverfügbarkeit und leistungsfähige analytische Methoden das Controlling und erfordern vermehrt das Einbringen statistischer und informationstechnologischer Fertigkeiten und Kenntnisse. An einem Fallbeispiel aus dem Marketing-Controlling zeigt der Beitrag den Einsatz von Methoden der Business Analytics und thematisiert die Aufgaben des Controllings im digitalen Zeitalter.
Calculation of accurate channel spacing of an AWG optical demultiplexer applying proportional method
(2015)
We report resent results on the fabrication and characterization of carbon nanogap interdigitated electrode arrays (IDAs) for biosensor applications based on redox cycling. The electrochemical results of the carbon electrodes are compared to our fabricated gold electrodes with similar nanogap distances. The amplification factor and the collection efficiency were recorded by chronoamperometry. Cyclic voltammetry (CV) was utilized to determine the oxidation and reduction potentials as well as for monitoring the electron transfer process. The different deposited carbon materials were characterized by Raman spectroscopy.At present, we successfully fabricated carbon nanogaps down to 80 nm and we are convinced to reach the present fabrication limit of about 30 nm (for gold and platinum electrodes) with carbon as electrode material as well. To the best of our knowledge, this is the first IDA nanogap sensor, which features a gap distance under 100 nm with amorphous carbon as electrode material. Moreover, we present a signal amplification of 32 for carbon electrodes by redox cycling, which is the highest reported amplification so far.
Whether at the intramolecular or cellular scale in organisms, cell-cell adhesion adapt to external mechanical cues arising from the static environment of cells and from dynamic interactions between neighboring cells. Cell-cell adhesions need to resist detachment forces to secure the integrity and internal organization of organisms. In the past, various techniques have been developed to characterize adhesion properties of molecules and cells in vitro, and to understand how cells sense and probe their environment. Atomic force microscopy and dual-pipette aspiration, where cells are mainly present in suspension, are common methods for studying detachment forces of cell-cell adhesions. How cell-cell adhesion forces are developed for adherent and environment-adapted cells, however, is less clear. Here, we designed the Cell-Cell Separation Device (CC-SD), a microstructured substrate that measures both intercellular forces and external stresses of cells towards the matrix. The design is based on micropillar arrays originally designed for cell traction-force measurements. We designed PDMS micropillar-blocks, to which cells could adhere and be able to connect to each other across the gap. Controlled stretching of the whole substrate changed the distance between blocks and increased gap size. That allowed us to apply strains to cell-cell contacts, eventually leading to cell-cell adhesion detachment, which was measured by pillar deflections. The CC-SD provided an increase of the gap between the blocks of up to 2.4-fold, which was sufficient to separate substrate-attached cells with fully developed F-actin network. Simultaneously measured pillar deflections allowed us to address cellular response to the intercellular strain applied. The CC-SD thus opens up possibilities for the analysis of intercellular force detachments and sheds light on the robustness of cell-cell adhesions in dynamic processes in tissue development.
Chancen zum Lernen nutzen
(2018)
In this study, we carried out the structural and thermal characterization of a medical-grade poly (lactide) (PLA) by SEC, TGA, DSC, NMR, ICP-MS and Py-GC/MS. Moreover, we investigated the laser-induced degradation occurring when ultrashort laser pulses (ULP) were employed to cut extremely thin polymer films prepared by solvent-casting. ULP polymer cutting technology is an interesting manufacturing process for its advantages in potential medical applications. In fact, heat transmission to the region surrounding the cuts is limited, so that the incisions are precise and the effects on the regions around them are small. In this way, the need for post-processing is reduced and ULP cutting becomes interesting for industrial applications. However, degradation induced by ULP may occur and compromise the properties of the polymer samples. To investigate this possibility, portions of PLA films, ultrashort laser cut (ULC) and uncut, were analysed by SEC, DSC, NMR and FTIR. Furthermore, PLA oligomers were studied by ESI-MS. Both SEC and NMR showed a decrease in the molecular weight. FTIR, ESI-MS and NMR spectra revealed the presence of olefin end groups originated from a \beta-H transfer mechanism, induced by heat and/or light (Norrish II mechanism). Additionally, the inspection of the ESI mass spectra highlighted the cleavage of ester bonds related to the Norrish I type mechanism, undetected by the other techniques.
Die Checkliste „Pflegedokumentation“ basiert auf einer Literaturrecherche. Verschiedene Artikel bildeten die Grundlage für die Kriterien der Checkliste „Defäkation in der Pflegedokumentation“. Anhand dieser Checkliste wird untersucht, ob die genannten Items in der Pflegedokumentation enthalten sind und wenn ja, ob diese dann auch tatsächlich ausgefüllt und welche begründeten Rückschlüsse daraus gezogen werden und wie die Umsetzung überprüft wird und Maßnahmen ggfs angepasst werden. Z.B. Möglichkeiten der Erprobung bestimmter Interventionen gut dokumentieren.
Die Checkliste „Sanitäre Einrichtung“ (Toilette, Badezimmer) basiert auf einer aktuellen Literaturstudie. Anhand verschiedener Fachtermen wurden in unterschiedlichen Datenbanken nach relevanten Artikeln gesucht, diese in Bezug auf die Fragestellung „Kriterien, die eine sanitäre Einrichtung (Toilette / Badezimmer) für Menschen in einer stationären Altenpflegeeinrichtung erfüllen muss“ analysiert und die entsprechenden geforderten Kriterien in die Checkliste aufgenommen.
Codegenerierung - Was man damit (nicht) machen kann. Varianten, Möglichkeiten und Einschränkungen
(2015)
Combining parallel pattern generation of electrohydrodynamic lithography with serial addressing
(2018)
Compact and high-resolution 256-channel silicon nitride based AWG-spectrometer for OCT on a chip
(2019)
We present design, simulation and technological verification of a compact 256-channel, 42-GHz silicon nitride based AWG-spectrometer. The spectrometer was designed for TM-polarized light with a central wavelength of 850 nm, applying “AWG-Parameters” tool. This design is based on a previous study of various AWG designs (8-channel, 100-GHz; 20-channel, 50-GHz; 40-channel, 50-GHz, 80-channel, 50-GHz and 160-channel, 50-GHz AWGs), which were all technologically verified. The spectrometer features small size and high resolution. It is integrated on OCT chip using standard CMOS processes. The SD-OCT system is developed to operate in a wavelength range from 800 nm to 900 nm, having 0.1 nm resolution.
In this paper, the design of three-dimensional configuration of Y-branch splitter is compared with Multimode Interference splitter. Both splitters use the IP-Dip polymer as a standard material for 3D laser lithography. The optical properties of the splitters for both approaches are discussed and compared.
Comparison of constraint-handling mechanisms for the (1,λ)-ES on a simple constrained problem
(2016)
This paper describes two different designs of 1×8 passive optical splitters. The first splitter consists of cascade arranged directional waveguide branches (Y-branch splitter) with (0.8×0.16) µm2 waveguide cross-section. The second splitter is based on multimode interference occurring in a large MMI coupler, which uses a self-imaging effect for beam propagation, exhibiting the same waveguide core size as a Y-branch splitter. The waveguide channel profile, used in both approaches, is based on a silicon nitride material platform, with a refractive index of core being nc = 1.925 and a refractive index of cladding ncl = 1.4575. The splitters are designed as a planar structure for a medical operating wavelength 850 nm. Design, simulation, and optimization of passive optical components are performed by a commercial photonic software tool BeamPROP simulation engine by RSoft Photonics Suite tool, employing beam propagation method. This work aims to find the minimum physical dimensions of the designed splitters with the satisfactory optical performance. According to the minimum insertion loss and minimum non-uniformity, the optimum length of the splitters is determined. Finally, the optical properties of splitters for both approaches are discussed and compared with each other.
Comparison of silicon nitride based 1x8 Y-branch splitters applying different waveguide structures
(2019)
This paper presents design, simulation and optimization of 1x8 Y-branch power splitters based on Si/SiO2/SiN/SiOx material platform. For the designs, two different waveguide structures were used, i.e. ridge and rib waveguides. The splitters were designed for 850 nm spectral optical window and the simulations were performed applying FEM and BPM methods in RSoft photonic tool. The aim of this work was to find minimum physical dimensions of the designed splitters occupying minimal space on PIC chip. The optimization was done with regards to high symmetrical splitting ratio and low insertion loss. Finally, the optical properties of both splitters were studied and compared with each other.