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The negative impact of social networks on supply chain management: systematic literature review
No full textThis systematic literature review examines the negative impacts of social media (SM) on supply chain management (SCM). Pre-defined selection criteria were used on four research questions to identify a hundred relevant publications from the Scopus database, including publishers such as Emerald, Elsevier, Springer, Inderscience, and Wiley. The review begins with the first research question – the characteristics of the selected publications. Then, the authors delve into the second question – negative impacts, such as reputational damage, profit losses, and unreliable data. The third question highlights supply chain (SC) processes that are particularly vulnerable to the influence of social media. In addressing the fourth question, the authors identified the most common social networks (SN) discussed in related literature. Despite the comprehensive research, no publication thoroughly explored these four research questions, pointing to gaps for future empirical research. The limitation of focusing solely on English-language literature and other disciplines suggests the need for broader studies. This work deepens understanding of this underexplored area and contrasts the documented positive impacts
Biblioteka informuoja, 2024 Nr. 16 (660)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.16 (660)202
Use of adsorbent made from paper and cardboard waste for removal of congo red dye from water
No full textTekstilės pramonė – viena iš svarbiausių lengvosios pramonės šakų visoje Europos Sąjungoje. Pagrindinės tekstilės pramonės aplinkosauginės problemos – didelis vandens suvartojimas ir jo užteršimas, naudojamų cheminių medžiagų įvairovė bei didelis energijos poreikis. Svarbu atkreipti dėmesį, jog dažiklių kiekis tekstilės pramonės nuotekose vis dar nėra reglamentuojamas. Pastaruoju metu dideliu savituoju paviršiaus plotu ir nedideliu svoriu pasižymintys adsorbentai, aerogeliai, sulaukė didelio susidomėjimo kaip perspektyvios dažiklius iš užteršto vandens šalinančios medžiagos. Celiuliozės aerogeliai yra nebrangūs, netoksiški. Šio tyrimo metu buvo nustatytas tekstilės pramonėje naudojamo kongo raudonojo dažiklio adsorbcijos efektyvumas naudojant iš popieriaus ir kartono atliekų susintetintą adsorbentą. Bendroji organinės anglies koncentracija buvo pasirinkta kaip kongo raudonojo dažiklio koncentracijos tirpale indikatorius. Tirtos skirtingos sudėties aerogelio kapsulės, celiuliozės kiekis jose skyrėsi nuo 3 % iki 5 %. Aerogelio kapsulėms, kurių sudėtyje buvo 3 % celiuliozės nuo bendros masės, esant 0,1 mg/l dažiklio koncentracijai, pasiektas 74,55 % bendrosios organinės anglies koncentracijos sumažėjimas, esant 1,0 mg/l – 73,68 %, esant 2,0 mg/l – 67,45 %, o esant 5,0 mg/l – 57,98 %. Aerogelio kapsulėms, kurių sudėtyje buvo 5 % celiuliozės nuo bendros masės, esant 0,1 mg/l, pasiektas 80,00 %, esant 1,0 mg/l – 76,04 %, esant 2,0 mg/l – 71,08 %, o esant 5,0 mg/l – 68,02 %.The textile industry is one of the most important light industries in the entire European Union. The main environmental problems of the textile industry are the high water consumption and its pollution, the variety of chemicals used and the high energy demand. It is important to note that the amount of dyes in textile industry wastewater is still not regulated. Recently, adsorbents with a large specific surface area and low weight, aerogels, have attracted great interest as promising materials for removing dyes from polluted water. Cellulose aerogels are inexpensive, non-toxic. During this study, the adsorption efficiency of Congo red, a dye used in the textile industry, was determined using an adsorbent synthesized from paper and cardboard waste. The total organic carbon concentration was chosen as an indicator of the concentration of the dye Congo red in the solution. Aerogel capsules of different compositions were tested, the cellulose content in them varied from 3% to 5%. For aerogel capsules containing 3% cellulose by total weight, at a dye concentration of 0.1 mg/l, a 74.55% reduction in total organic carbon was achieved, at 1.0 mg/l – 73.68%, at 2.0 mg/l – 67.45%, and at 5.0 mg/l – 57.98%. For aerogel capsules containing 5% cellulose by total weight, at 0.1 mg/l, 80.00% was achieved, at 1.0 mg/l – 76.04%, at 2.0 mg/l – 71.08%, and at 5.0 mg/l – 68.02%.Taip / Ye
Impact of modified biopolymer on properties of clay composites
No full textThis research investigates the impact of a modified biopolymer, retrograded corn starch, on the physical-mechanical and hygroscopic properties of clay composites. Clay composites were produced using varying amounts of the modified biopolymer (2.5%, 5%, 7.5%, 10%). Results showed that the addition of the retrograded starch polymer had a significant effect on the properties of the clay composites. Incorporating of retrograded starch polymer into the clay matrix resulted in a 72% increase in compressive strength (6.8 to 11.9 MPa), a 29% increase in surface moisture adsorption (from 141.1 to 182.43 g/m2), and a 36% decrease in the initial rate of capillarity absorption (from 0.55 to 0.35 g/cm2*min)
Biblioteka informuoja, 2024 Nr. 19 (663)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.19 (663)202
Future citizen competences in the context of community initiative
No full textRecently, there has been an increased focus on different competence models to define and assess the skills and abilities needed in various domains. These models provide a comprehensive framework for understanding and evaluating the competencies required for success in specific fields or contexts. Some correspond well with the definition of the Future Citizen and are dedicated to solving the same general questions – how do we describe the human being, who we expect to rise, who will be successful in the future, and who can handle the challenges that the world and environment will give. The future citizen competence model should describe the multifaceted nature of Future Citizens (FC) in a rapidly changing world. This article aims to identify the most critical competencies for the young person to participate successfully and actively in citizen initiatives. In pursuing understanding and cultivating the skills required for Future Citizenship (FC) in an ever-evolving world, our methodology draws inspiration from and aligns with four prominent European competence models and scientific research. EntreComp, Lifecomp, DigComp, and GreenComp collectively provide a comprehensive foundation to explore, define, and assess the competencies essential for the Future Citizen.Taip / YesIErasmus+KA220-YOU [KA220-YOU-511CDAA
Efficiency of iron-containing filter filters in the removal of soluble phosphorus
No full textŠio darbo tikslas – išbandyti geležies turinčių medžiagų efektyvumą sorbuoti tirpųjį fosforą iš realių, biologiniu būdu jau išvalytų, nuotekų. Tyrimams pasirinktos ir į tris eksperimentinio stendo kolonėles patalpintos trys medžiagos, savo sudėtyje turinčios geležies: sorbentai GEH®102, SBGx ir plieno drožlės. Filtravimas vyko 0,74 m/h greičiu iš viršaus į apačią, sorbentų užpildams visą laiką esant apsemtiems, virš užpildų palaikant 25 cm aukščio skysčio sluoksnį. Adsorbentas GEH®102, skirtas geriamajam vandeniui ruošti, išsiskyrė efektyvumu (efektyvumas iki 98 %) šalinant PO4-P iš biologiškai valytų nuotekų, kuriose skendinčiųjų medžiagų koncentracija yra nedidelė (<2 mg/l). Miltelių pavidalo adsorbentas SBGx maišomas su smėliu, jo efektyvumas šalinant PO4-P iš nuotekų svyravo nuo 3 iki 41 %. Plieno drožlių užpildas yra tinkamas PO4-P šalinti iš buitinių nuotekų, šalinimas vyko 91–94 % efektyvumu. Plieno drožlės yra atlieka, kurios antrinis panaudojimas nuotekoms valyti būtų naudingas aplinkos darnumui, todėl rekomenduojama šioje srityje atlikti daugiau tyrimų.The aim of this work is to test the effectiveness of iron-containing materials in sorbing soluble phosphorus from real, biologically treated wastewater. Three materials containing iron were chosen for the research: sorbents GEH®102, SBGx and steel chips, which were placed in 3 columns of the experimental bench. Filtration took place at a speed of 0.74 m/h from top to bottom, the sorbent fillers were covered all the time, and a 25 cm high liquid layer was maintained above the fillers. The GEH®102 adsorbent for drinking water treatment has been shown to be effective (up to 98% efficiency) in removing PO4-P from biologically treated wastewater with low suspended solids concentrations (<2 mg/l). Powdered adsorbent SBGx was mixed with sand, its efficiency for PO4-P removal from wastewater ranged from 3 to 41%. Steel chip filler proved to be suitable for PO4-P removal from domestic wastewater, with 91–94% efficiency. Steel shavings are a waste whose secondary use for wastewater treatment would be beneficial in the context of environmental sustainability, and more research is recommended in this area.Taip / Ye
Analysis of spatial distribution of narcotics and their use in vilnius municipality registered by Lithuanian police in 2015–2022
No full textŠių laikų pasaulis yra stipriai paveiktas psichoaktyviųjų medžiagų, jų vartojimas smarkiai auga ir tai tampa vis skaudesne visuomenės problema net ir Lietuvoje. Ši problema yra labai skaudi ir sparčiai besivystanti, todėl nenuostabu, kad sprendimo, kaip jos išvengti, dar nėra. Dėl šios priežasties reikalingi įvairūs tyrimai, kuriais remiantis būtų galima mažinti šios problemos pasekmes visuomenei. Šio darbo tikslas – supažindinti su narkotinių medžiagų vartojimo pažeidimų erdvine sklaida Vilniaus miesto savivaldybėje 2015–2022 m. laikotarpiu. Analizuojami esminiai kartografiniai metodai, kurių pagalba buvo sukurti šios temos žemėlapiai. Tikimasi, kad jie bus panaudoti ieškant šios problemos sprendimo būdų. Taip pat plačiai nagrinėjama Lietuvos policijos registruotų įvykių duomenų bazė. Aprašoma darbo eiga, duomenims tvarkyti ir redaguoti naudotos technologijos, pateikiamos išvados.The world today is strongly affected by psychoactive substances, their use is on the rise, and it is becoming an increasingly painful problem for society even in Lithuania. This problem is very painful and rapidly changing before our very eyes, so it is not surprising that there is no solution to avoid this problem yet. For this reason, various studies are needed, based on which it would be possible to reduce the consequences of this problem for society. The purpose of this work is to familiarize with the spatial distribution of violations of the use of narcotic substances in Vilnius city municipality in 2015–2022 period. The essential cartographic methods, with the help of which the maps on this topic were created, are analysed. It is expected that they will be used to find ways to solve this problem, and the database of events registered by the Lithuanian police will also be studied more widely. The work process is described, the technologies used for data management and editing are presented, and the conclusions will be discussed.Taip / Ye
The Concept of Reactive Power Management System
No full textThis publication presents the concept of a Building Management System and Reactive Power Management System in one software. The need for such a reactive power management system is related to the increase in the number of components influencing reactive power in the building's power distribution lines. Such components are light-emitting diode-based sources, variable frequency drives and others. By supplementing the traditional Building Management System with a software plug-in managing these devices with the aim of maintaining the power factor close to unity, it is possible significantly reduce electricity bills. This publication reviews the influence of components connected to building power distribution lines on reactive power and suggests a management plug-in for these components to reduce the reactive power.Taip / Ye
Managing longevity risk in Polish pension system with the use of behavioral incentives
No full textThe longevity risk is the risk of living longer than expected. In relation to pension systems, the concept of pension longevity is utilized. On an individual basis, the realization of longevity risk can lead to the depletion of pension savings. Group (aggregate) longevity risk – the risk that a specific age cohort will live longer than expected – is significant for public and private institutions obligated to pay lifetime annuities. The aim of this paper is to present preliminary research results on the implementation of behavioral incentives to mitigate longevity risk in the Polish pension system.Taip / YesPoznan University of Technology0812/SBAD/418