Optimisation of picking process in manual warehouses

Skladiščni sistemi so postavljeni pred širok spekter izzivov pri zagotavljanju kakovostnih storitev za stranko. Med vsemi procesi, ki se izvajajo v skladišču, je proces nabiranja časovno najzahtevnejši, zato je ključno, da je izveden čim bolj optimalno. V okviru magistrske naloge smo se zato lotili optimizacije nabiralnega procesa v ročnem skladišču. Predlagali smo hierarhični logični model skladišča, ki s svojo strukturo zmanjša število lokacij, ki jih morajo pregledati implementirani algoritmi za iskanje najkrajše nabiralne poti. Hkrati nam tovrstni model omogoča, da podrobno deljenje lokacij ne vpliva na izvajanje algoritma. Pripravili smo modul za optimizacijo nabiralne poti, ki glede na velikost in tip problema izbere enega od treh implementiranih algoritmov. Prenovili smo procese, povezane z uporabo polavtomatskih viličarjev, in razvili grafični spletni vmesnik za pregled pogostosti nabiranja.Warehouse operators and warehouse management systems encounter a broad spectrum of challenges to ensure the shortest possible shipping times to their customers and maintain their position on the market. The picking process is the most time-demanding among all core warehouse processes. Optimisation of picking is crucial for effective warehouse operation, since it represents the majority of warehousing costs. In this thesis we analyzed, proposed and implemented optimisations of the picking process in the manual warehouse. We prepared a logical model of the warehouse, which is based on a hierarchical representation of the warehouse locations. Using this model we reduced the number of locations, which have to be considered during the computation of the shortest picking path in the implemented algorithms. We developed a module for picking path optimisation, which selects one of three implemented algorithms based on the problem size and the warehouse type. To further improve the picking process we introduced changes to the semi-automatic forklift operations and developed a graphical web interface for the warehouse picking heatmap

Implementation of a mobile devices for GPS tracking

Internet stvari oz. IoT je v zadnjih nekaj letih ena izmed najbolj vročih tem s področja računalništva in elektrotehnike. Jedro vsake IoT naprave je vgrajeni sistem, ki temelji na mikrokrmilniku, senzorjih za zajem podatkov iz okolja in aktuaktorjev za izvajanje fizičnih akcij. V diplomskem delu smo se lotili implementacije vgrajenega sistema, ki bi se lahko vgradil v potovalni kovček in nam ponujal lokacijske podatke in podatke o mikroklimi kovčka. Poleg vgrajenega sistema pa smo pripravili tudi zaledni strežniški del, ki shranjuje podatke prejete iz vgrajenega sistema, in mobilno aplikacijo za mobilne naprave z operacijskim sistemom Android.In recent years, internet of things or IoT became one of the hottest topics in field of computer science and electrical engineering. The core of each IoT device is embedded system, which is based on microcontroller, sensors and actuators. Based on data obtained by sensors, microcontroller generates response, which is executed by actuators. We developed embedded system, which could be used as a tracking device for suitcases. Apart from embedded system, we developed server-side application and mobile application for devices with Android operating system. Server application is used to store the data obtained from tracking device and acts as intermediate point between mobile application and embedded system. Mobile application offers user interface for interaction with tracking device

Primer koncepta 3D modeliranja na osnovi virtualne resničnosti

This thesis illustrates a concept for a virtual reality based application design and implements a 3D modeling application using VR technology. The application itself allows the user to perform 3D modeling while moving around VR space in various ways. The models may be created from scratch and manipulated by different tools or imported as well as exported during application runtime. Prior to implementation presentation, the reader gets familiarized with terminology and concepts of 3D modeling field. Furthermore, the implementation addresses more abstract thesis questions about how to make use of limited input as efficiently as possible, how to interact with objects in VR space intuitively, how to design a versatile 3D GUI system which is handy for the user, etc. The latter goal speaks of the necessity for striving toward new ideas to make VR as useful as possible in different industries. Technology is relatively new and a lot of its potential undiscovered. The application is written in C++, using Unreal Engine 4 framework and HTC Vive hardware for VR. It covers intended 3D modeling goals while also presenting some interesting and generic ways of using VR in this type of applications.Naloga ilustrira koncept uporabe VR tehnologije ter dobrih razvojnih praks na primeru izdelave aplikacije namenjenje 3D modeliranju, ki za svoje delovanje uporablja tehnologijo virtualne resničnosti. Aplikacija nudi uporabniku možnost 3D modeliranja v VR prostoru, po katerem se lahko premika. 3D modele je možno ustvariti in jih modificirati, lahko pa so tudi uvoženi ali izvoženi iz programa med uporabo. Bralec je še pred samo predstavitvijo implementacije seznanjen s ključnimi termini in koncepti s področja 3D modeliranja. Poleg modeliranja pa implementacija poskuša odgovoriti tudi na bolj abstraktna vprašanja glede doseganja maksimalne učinkovitosti glede na omejen nabor vhodnih kontrol, glede intuitivne interakcije z objekti v VR prostoru, izdelave uporabniku prijaznega 3D GUI, ipd. Ta cilj govori o pomembnosti stremenja proti novim načinom uporabe VR in snovanja tovrstnih aplikacij, saj je s tem VR bolj uporaben v industriji. Tehnologija je - v komercialno dostopnejši obliki - relativno mlada, zato je mnogo njenega potenciala še vedno neodkritega. Aplikacija je napisana v programskem jeziku C++ in uporablja programsko ogrodje Unreal Engine 4. Strojna oprema za VR je HTC Vive. Aplikacija zadostuje zadanim ciljem, kar se tiče zahtev 3D modeliranja, poleg tega pa predstavi še nekaj zanimivih in generičnih načinov uporabe VR v tovrstnih aplikacijah

Investigation of rain-on-snow floods under climate change

Rain-on-snow (ROS) floods can cause economic damage and endanger human lives due to the compound effect of rainfall and snowmelt, especially under climate change. In this study, possible future changes of seasonality, magnitude and frequency characteristics of ROS floods were investigated for the selected catchments in Slovenia, Europe. For this purpose, five global/regional climate models (GCM/RCM) combinations were applied using the RCP4.5 climate scenario for the period 1981-2100. To determine ROS floods characteristics in the future, a lumped conceptual hydrological model Génie Rural à 6 paramètres Journalier (GR6J) with snow module CemaNeige was applied. The results indicate that the number of ROS floods could increase in the future. Moreover, also the magnitudes of extreme ROS floods could increase, while a slight decrease in the median values of ROS flood magnitudes was observed. The strength of seasonality for a high-altitude catchment could decrease in the future. A slight shift in the average ROS floods timing could be expected. Furthermore, a catchment located in a temperate continental climate could have a different response to the climate change impact in comparison to a catchment located in a mountain climate with alpine characteristics. Additionally, differences among investigated climate models show a large variability

Investigation of low- and high-flow characteristics of karst catchments under climate change

It is not clear how projected climate change will impact the hydrological functioning of complex catchments that have significant karst characteristics. Therefore, in this paper we focused on the investigation of the low- and high-flow characteristics of the karst Ljubljanica River catchment. One smaller (51 km$^2$) and one larger (1135 km$^2$) catchment were selected in order to investigate the projected climate change impact on the hydrological conditions. For the investigation of the hydrological situation in the future, we used a lumped conceptual hydrological model. The model was calibrated using past measured daily data. Using the calibrated model, we investigated the impact of five different climate models outputs for the moderately optimistic scenario (RCP4.5). We investigated the situation in next 30-years periods: 2011-2040, 2041-2070, and 2071-2100. Several low and high-flow indices were calculated and compared. The results indicate that a summer precipitation decrease (i.e., 2011-2070) could lead to lower low-flow values for the investigated areas, which could increase the vulnerability of karst areas. Thus, additional focus should be given to water resource management in karst areas. On the other hand, mean flow could increase in the future. The same also applies for the high-flows where flood frequency analysis results indicate that a climate adaptation factor could be used for the hydrotechnical engineering design. However, differences among investigated models are large and show large variability among investigated cases

Vpliv podnebnih sprememb na pojavljanje zemeljskih plazov v sredini 21. stoletja v Sloveniji

Slovenia is affected by extreme and intense rainfall that triggers numerous landslides every year, resulting in significant human impact and damage to infrastructure. Previous studies on landslides have shown how rainfall patterns can influence landslide occurrence, while in this paper, we present one of the first study in Slovenia to examine the impact of climate change on landslides in the mid-21st century. To do this, we used the Representative Concentration Pathway (RCP) 4.5 climate scenario and future climatology simulated by six climate models that differed from each other as much as possible while representing measured values of past climate variables as closely as possible. Based on baseline period (1981-2010) we showed the number of days with exceedance of rainfall thresholds and the area where landslides may occur more frequently in the projection period (2041-2070). We found that extreme rainfall events are likely to occur more frequent in the future, which may lead to a higher frequency of landslides in some areas.Vsako leto Slovenijo prizadenejo ekstremne in močne padavine, ki sprožijo številne zemeljske plazove, kar povzroči znaten vpliv na človeka in škodo na infrastrukturi. Prejšnje študije plazov so pokazale, kako padavine vplivajo na pojav plazov, medtem ko v tem prispevku predstavljamo eno izmed prvih študij v Sloveniji, ki proučuje vpliv podnebnih sprememb na zemeljske plazove sredi 21. stoletja. V ta namen smo uporabili scenarij značilnih potekov vsebnosti toplogrednih plinov (RCP4.5) in uporabili simulacije šestih podnebnih modelov, ki so se med seboj čimbolj razlikovali, hkrati pa kar najbolj enako predstavljali izmerjene vrednosti podnebnih spremenljivk v obdobju meritev. Na podlagi referenčnega obdobja (1981-2010) prikazujemo število dni, ko padavine presežejo sprožilne količine padavin in območja, kjer se lahko plazovi v projekcijskem obdobju (2041-2070) pogosteje pojavljajo. Rezultati kažejo, da se bodo ekstremni padavinski dogodki v prihodnosti zelo verjetno pojavljali pogosteje kot danes, kar lahko na nekaterih območjih povzroči pogostejše pojavljanje zemeljskih plazov

Influence of nickel on niobium nitride formation in as-cast stainless steels

The influence of the nickel content and cooling rate on niobium nitride precipitation in as-cast stainless steels were analysed. Niobium microalloying is important for mechanical properties and the prevention of intergranular corrosion in stainless steels. However, coarse precipitates can negatively affect steel properties. The precipitation of NbN depends on thermodynamic conditions, which are dictated by the chemical composition and temperature. The thermodynamic computations were used to estimate niobium nitride precipitation. Additionally, segregation models were used to predict precipitation. Three steel batches with different nickel contents (9 wt.%, 4.7 wt.%, and 0.16 wt.%) were prepared in an induction furnace and cast into sand moulds. The polished and etched samples were examined with an optical microscope, followed by a more detailed examination using a scanning electron microscope. An automatic scanning electron microscope analysis of the niobium particles was performed to obtain particle number and size distribution. Primary niobium carbonitrides, eutectic phases, and heterogenous nucleations on MnS inclusions were observed. As the proportion of nickel in the solution decreased, the solubility of nitrogen in the melt increased, which is manifested by a lower formation of primary and eutectic niobium carbonitrides, while MnS non-metallic inclusions played an important role in the heterogeneous nucleation

Investigation of Low- and High-Flow Characteristics of Karst Catchments under Climate Change

It is not clear how projected climate change will impact the hydrological functioning of complex catchments that have significant karst characteristics. Therefore, in this paper we focused on the investigation of the low- and high-flow characteristics of the karst Ljubljanica River catchment. One smaller (51 km2) and one larger (1135 km2) catchment were selected in order to investigate the projected climate change impact on the hydrological conditions. For the investigation of the hydrological situation in the future, we used a lumped conceptual hydrological model. The model was calibrated using past measured daily data. Using the calibrated model, we investigated the impact of five different climate models outputs for the moderately optimistic scenario (RCP4.5). We investigated the situation in next 30-years periods: 2011−2040, 2041−2070, and 2071−2100. Several low and high-flow indices were calculated and compared. The results indicate that a summer precipitation decrease (i.e., 2011−2070) could lead to lower low-flow values for the investigated areas, which could increase the vulnerability of karst areas. Thus, additional focus should be given to water resource management in karst areas. On the other hand, mean flow could increase in the future. The same also applies for the high-flows where flood frequency analysis results indicate that a climate adaptation factor could be used for the hydrotechnical engineering design. However, differences among investigated models are large and show large variability among investigated cases

Climate change increases the number of landslides at the juncture of the Alpine, Pannonian and Mediterranean regions

Abstract During the next few decades, changes in rainfall frequency and magnitude are expected to have major impacts on landscape evolution, social, and economic aspects of human society. We focus on seasonal rainfall variations by the end of the twenty-first century to define affected landslide-prone areas, future landslide alerts and the impact of landslides on landscape development in the juncture of the Alpine, Pannonian, and Mediterranean region. A moderate and a worst-case climate scenario from CMIP5 global climate simulations were considered to determine the impact of rainfall on the two most common types of landslides in region, shallow and deep-seated landslides. The observed changes in the occurrence of shallow landslides are significant, especially in the winter months, where we can expect more landslide-prone areas compared to the baseline period. Shallow landslides will have a greater impact on the landscape in spring and summer than deep-seated landslides, especially in vineyards