Model and algorithm of two-stage distribution location routing with hard time window for city cold-chain logistics

Taking cold-chain logistics as the research background and combining with the overall optimisation of logistics distribution networks, we develop two-stage distribution location-routing model with the minimum total cost as the objective function and varying vehicle capacity in different delivery stages. A hybrid genetic algorithm is designed based on coupling and collaboration of the two-stage routing and transfer stations. The validity and feasibility of the model and algorithm are verified by conducting a randomly generated test. The optimal solutions for different objective functions of two-stage distribution location-routing are compared and analysed. Results turn out that for different distribution objectives, different distribution schemes should be employed. Finally, we compare the two-stage distribution location-routing to single-stage vehicle routing problems. It is found that a two-stage distribution location-routing system is feasible and effective for the cold-chain logistics network, and can decrease distribution costs for cold-chain logistics enterprises.Peer ReviewedPostprint (published version

Optimasi Interest Income dengan Penetapan Interest Rate Fasilitas Revolving Credit Line

Perbankan memiliki peranan strategis sebagai lembaga intermediasi yang akan menyalurkan dana dari pihak yang memiliki kelebihan dana (savers) dengan kedudukan sebagai penabung ke pihak yang memerlukan dana (borrowers). Hal tersebut sejalan dengan kebutuhan dari perusahaan untuk mendapatkan pendanaan untuk menunjang kegiatan perusahaan. Perbankan akan menyediakan pendanaan bagi perusahaan berupa credit line yang dikenal juga sebagai revolving credit line untuk memenuhi kebutuhan likuiditas jangka pendek serta juga menyediakan kredit berjangka untuk pembiayaan investasi jangka panjang. Fasilitas revolving credit line memberikan keleluasaan dari perusahaan sebagai debitur untuk menggunakan fasilitas kredit dengan batas atas sesuai dengan maksimum kredit yang diberikan dengan kewajiban untuk melakukan pembayaran beban bunga sesuai dengan nilai penggunaan fasilitas revolving credit line. Fleksibiltas tersebut menyebabkan tingkat utilitas penggunaan fasilitas revolving credit line belum optimal sehingga akan mempengaruhi pencapaian interest income. Penelitian ini dilakukan untuk mengetahui pengaruh karakteristik credit line, perusahaan sebagai debitur, dan perbankan sebagai kreditur terhadap utilitas fasilitas revolving credit line serta dilakukan permodelan regresi untuk prediksi utilitas credit line (UCL) debitur. Berdasarkan persamaan yang dihasilkan diketahui bahwa Line Age (LAGE), Asset, Return of Asset (ROA), dan Equity to Asset (ETA) berpengaruh negatif terhadap UCL. Sedangkan rasio Non Performing Loan (NPL) berpengaruh positif terhadap UCL. Optimasi interest income dilakukan dengan data UCL berdasarkan prediksi dari persamaan regresi tersebut. Metode yang digunakan dalam optimasi interest income adalah metode linear programming. Hasil optimalisasi tersebut menjadi acuan kreditur untuk menetapkan interest rate kepada debitur. Adapun hasil optimasi yang dilakukan terhadap asset eksisting mampu mencapai interest income sebesar Rp.241,63 M dan target yield yang ditetapkan sebesar 9,00%. Optimasi tersebut dapat pula dilakukan guna perencanaan ekspansi penyaluran kredit sehingga perbankan memiliki acuan range maksimum penyaluran kredit dalam setiap tiering suku bunga dan juga acuan penetapan interest rate atas fasilitas kredit yang disalurkan kepada debitur. ===================================================================================================================================== Banking has a strategic role as an intermediary institution that will fund from parties who have excess funds (savers) with a position as savers to those who need funds (borrowers). This is in line with the needs of companies to obtain funding to support company activities. The bank will provide funding for companies in the form of a credit line, also known as a revolving credit line to meet short-term liquidity needs and also provide term loans for long-term investment financing. Revolving credit line provides flexibility of the company as a debtor to use credit facilities depends on maximum credit limit and the company must pay interest expense which is calculated based on utility of credit line. This flexibility causes utility of credit line facilities to be suboptimal so that it will affect the achievement of interest income. This study was conducted to determine the effect of credit line characteristics, companies as debtors, and banks as creditors on the utility of revolving credit line facilities and create regression modeling to predict debtor credit line (UCL) utilities. Based on the resulting equation it is known that Line Age (LAGE), Asset, Return of Asset (ROA), and Equity to Asset (ETA) have a negative effect on UCL. While the Non Performing Loan (NPL) ratio has a positive effect on UCL. Interest income optimization used UCL based on prediction model by linear regression. The method used in optimizing interest incoms is linear programming method. The results of this optimization become a reference for creditor to set interest rates for debtors. Optimization of existing assets are able to achieve interest income at IDR 241,63 billion and achieve yield target at 9,00%. Optimization interest income can be applied to plan credit expansion so creditor has reference the maximum range of credit distribution and also determine of interest rate’s debtors

Entropy maximizing evolutionary design optimization of water distribution networks under multiple operating conditions

The informational entropy model for flow networks was formulated over 30 years ago by Tanyimboh and Templeman (University of Liverpool, UK) for a single discrete operating condition that typically comprises the maximum daily demands and was undefined for water distribution networks (WDNs) under multiple operating conditions. Its extension to include multiple independent discrete operating conditions was investigated experimentally herein considering the relationships between flow entropy and hydraulic capacity reliability and redundancy. A novel penalty-free multi-objective genetic algorithm was developed to minimize the initial construction cost and maximize the flow entropy subject to the design constraints. Furthermore, optimized designs derived from the maximum daily demands as a single discrete operating condition were compared to those derived from a combination of discrete operating conditions. Optimized designs from a combination of discrete operating conditions outperformed those from a single operating condition in terms of performance and initial construction cost. The best results overall were achieved by maximizing the sum of the flow entropies of the discrete operating conditions. The logical inference from the results is that the flow entropy of multiple discrete operating conditions is the sum of their respective entropies. In addition, a crucial property of the resulting flow entropy model is that it is bias free with respect to the individual operating conditions; hitherto a fundamental weakness concerning the practical application of the flow entropy model to WDNs is thus addressed

Coping with the Rise of E-commerce Generated Home Deliveries through Innovative Last-Mile Technologies and Strategies

Caltrans 65A0686 Task Order 066USDOT Grant 69A3551747114E-commerce can potentially make urban goods flow economically viable, environmentally efficient, and socially equitable. However, as e-retailers compete with increasingly consumer-focused services, urban freight witnesses a significant increase in associated distribution costs and negative externalities, particularly affecting those living close to logistics clusters. Hence, to remain competitive, e-retailers deploy alternate last-mile distribution strategies. These alternate strategies, such as those that include the use of electric delivery trucks for last-mile operations, a fleet of crowdsourced drivers for last-mile delivery, consolidation facilities coupled with light-duty delivery vehicles for a multi-echelon distribution, or collection-points for customer pickup, can restore sustainable urban goods flow. Thus, in this study, the authors investigate the opportunities and challenges associated with alternate last-mile distribution strategies for an e-retailer offering expedited service with rush delivery within strict timeframes. To this end, the authors formulate a last-mile network design (LMND) problem as a dynamic-stochastic two-echelon capacitated location routing problem with time-windows (DS-2E-C-LRP-TW) addressed with an adaptive large neighborhood search (ALNS) metaheuristic

Logistiikan päätökset ja menetelmät päätöksenteon tukena

Tutkimus käsittelee toimitusketjujen hallintaa, sen työkaluja ja nykytilaa. Viitekehyksenä toimitusketjujen hallinnan tarkastelulle ovat logistiikan päätökset ja niissä käytettävät päätöksenteon tuen menetelmät. Toimitusketjujen hallinnasta on tullut organisaatioille merkittävä keino hankkia kilpailuetua ja lisätä asiakastyytyväisyyttä. Logistiikan päätöksiä tehdään osana toimitusketjujen hallintaa ja ne voivat aiheuttaa merkittäviä muutoksia toimitusketjuihin. Toimitusketjut ovat monimutkaistuneet viime vuosikymmeninä. Tämä on entisestään vaikeuttanut niihin liittyvää päätöksentekoa. Toimitusketjuihin liittyvää päätöksenteon tukea on tutkittu runsaasti 2010-luvulla. Puolustusvoimien toimitusketjut ja sitä kautta logistiikkajärjestelmä koostuu osin siviilikomponentista. Tästä johtuen siviililogistiikan seuraaminen on tärkeä osa Puolustusvoimien logistiikan kehittämistä. Tutkimuksessa kartoitetaan siviililogistiikassa käytettyjä päätöksenteon tuen menetelmiä. Tutkimus tähtää Puolustusvoimallisen siviililogistiikkaa käsittelevän tutkimuspohjan laajentamiseen. Tutkimuksen päätutkimuskysymyksenä on: Millaisia ovat siviilikomponentissa käytetyt logistiikan päätöksenteon tuen menetelmät? Apututkimuskysymyksinä ovat: 1) Mitä päätöksiä varten päätöksenteon tuen menetelmiä on kehitetty? 2) Mitä menetelmiä käytetään minkäkin päätöksen tekemisen tukena? Tutkimusmenetelmänä on systemaattinen kirjallisuuskatsaus, jolla selvitetään siviililogistiikassa käytettäviä päätöksenteon tuen menetelmiä. Teorialuvuissa taustoitetaan tutkimusongelmaa käyttäen menetelmänä kuvailevaa kirjallisuuskatsausta. Työssä kartoitetaan logistiikan päätöksiä ja päätöksen-teon tukea ilmiöinä. Systemaattinen kirjallisuuskatsaus toteutetaan Finkin-mallin mukaisesti. Tutkimusaineisto koostuu Scopus-tietokannasta löytyvistä, vuosina 2017–2021 julkaistuista vertaisarvioiduista artikkeleista. Systemaattisella kirjallisuuskatsauksella vastataan tutkimuksen apututkimuskysymyksiin ja tuetaan päätutkimuskysymykseen vastaamisessa. Tutkimuksen perusteella päätöksenteon tuen menetelmät ovat keskittyneet kumppaneiden valintaan sekä toimitusketjujen rakenteen suunnitteluun. Päätöksenteon tukena käytetään pääasiasiallisesti erilaisia monikriteerisen päätösanalyysin sekä matemaattisen mallinnuksen ja optimoinnin menetelmiä. Päätöksenteossa korostuu tutkimuksen perusteella kestävän kehityksen mukaisten arvojen huomioiminen sekä resilienssin kasvattaminen toimitusketjuissa. Edelleen myös kustannusten minimointi ja tuoton maksimointi ovat säilyneet merkittävinä ajureina päätöksenteossa

Sustentabilidade e resiliência num problema de localização-distribuição

A sustentabilidade e a resiliência constituem duas tendências com importância significante. O objetivo central dos gestores foi, e continua a ser, a satisfação das expectativas dos clientes ao menor custo possível. Contudo, a fim de preservarem a sustentabilidade da sua vantagem competitiva, as organizações enfrentam agora novos desafios. Encontrar um compromisso entre os lucros obtidos e as externalidades geradas na comunidade e no planeta evidencia-se um interesse essencial, perante as crescentes preocupações ambientais e sociais. Ademais, a incerteza e a sujeição a uma multiplicidade de riscos de disrupção compelem as empresas a tornarem os seus sistemas mais resilientes. Incentivar as organizações a considerar estes aspetos demonstra-se uma pretensão desafiante quando os custos implicados são elevados e não proporcionam um retorno evidente para as partes interessadas. A Análise Multiobjetivo pode contribuir para a identificação dos trade-offs entre os aspetos ambientais e de resiliência e o influente fator custo. A função logística representa uma parte considerável das despesas de uma organização e os seus custos podem ser substancialmente reduzidos, através de um planeamento adequado das redes de distribuição. Os problemas de localização-distribuição combinam, de forma integrada, as decisões logísticas de localização e de distribuição. Por conseguinte, o trabalho apresentado neste documento aborda um problema de localização-distribuição multiobjetivo, no qual os conceitos de resiliência e de sustentabilidade são integrados e modelados sob a forma de funções objetivo. Os resultados obtidos para duas instâncias de teste permitiram concluir que, embora as soluções mais amigas do ambiente não sejam necessariamente as de custo mais elevado, o mesmo não se verifica com as mais resilientes. No entanto, o modelo proposto permitiu a obtenção de soluções que apresentam um bom compromisso entre a resiliência das redes logísticas de distribuição, os impactos ambientais resultantes da sua atividade e os custos totais envolvidos.Sustainability and resilience are two trends of significant importance. The central objective of managers has been, and continues to be, to meet customer expectations at the lowest possible cost. However, to preserve the sustainability of their competitive advantage, organizations now face new challenges. Finding a compromise between profits and the externalities generated in the community and on the planet is an essential interest due to growing environmental and social concerns. In addition, uncertainty, and exposure to a diversity of disruptive risks forces companies to make their systems more resilient. Encouraging organizations to consider these aspects proves to be a challenging goal when the costs involved are high and do not provide a clear return for stakeholders. Multi-objective Analysis can help to identify the trade-offs between environmental and resilience aspects and the influential cost factor. The logistics function represents a considerable part of an organization's expenses, and its costs can be substantially reduced through proper planning of distribution networks. Location-routing problems handle, in an integrated way, the logistical decisions of location and distribution. Therefore, the work presented in this document addresses a multi-objective location-routing problem, in which the concepts of resilience and sustainability are integrated and modeled in the form of objective functions. The results obtained for two test instances allowed to conclude that, although the most environmentally friendly solutions are not necessarily the ones with the highest cost, the same is not true for the most resilient ones. However, the proposed model enabled the generation of solutions that demonstrated a good compromise between the resilience of distribution logistics networks, the environmental impacts resulting from their activity and the total costs involved.Mestrado em Engenharia e Gestão Industria

Gestaltung nachhaltiger Logistik-Konzepte im urbanen Wirtschaftsverkehr : Entscheidungsunterstützung mit Optimierungsmodellen

Die vorliegende kumulative Dissertation stellt die Zusammenfassung von zehn wissenschaftlichen Artikeln im Bereich des urbanen Wirtschaftsverkehrs dar. Dabei geht es grundsätzlich um die Untersuchung neuer Logistik-Konzepte als Lösungsansatz für eine gleichzeitige Berücksichtigung ökonomischer und ökologischer Ziele bei der Ausübung von Transportaktivitäten in urbanen Räumen. Dazu werden mathematische Optimierungsmodelle und Entscheidungsunterstützungssysteme präsentiert, welche den Zielkonflikt zwischen einer Kosten- und einer Emissionsminimierung adressieren. Diese sind durch die Anwendung von Methoden des Operations Research und der Informationssystem-Forschung entstanden. Darüber hinaus erfolgt die kritische Reflektion über die behandelten Themen, die genutzten Forschungsmethoden und die entwickelten Lösungsansätze. Drei Themen werden in der Dissertation ausführlich dargestellt: (1) Nachhaltige urbane Paketzustellung: Es wird ein Optimierungsmodell präsentiert, welches in ein Entscheidungsunterstützungssystem eingebettet ist und die bestmögliche Gestaltung eines alternativen Logistik-Konzepts für die Zustellung von Paketen in Städten ermöglicht. Dabei geht es um die Bestimmung der Positionen von Mikro-Depots als Orte der Zwischenlagerung sowie der dazugehörigen Fahrzeugflotte. (2) Nachhaltige e-Grocery Zustellung: Für die Lieferung von online bestellten Verbrauchsgütern wie Lebensmitteln oder Haushaltsartikeln wird ein neues Logistik-Konzept entworfen. Hierbei erfolgt eine Verkürzung der letzten Meile durch den Einsatz von temperierten Umschlagspunkten sowie eine Integration von Lastenfahrrädern und Kunden-Selbstabholungen. Ein dreistufiger Lösungsansatz ermöglicht die Optimierung der Standorte der Umschlagspunkten sowie der Fahrzeugrouten. (3) Individuelle Routenoptimierung: Es wird ein Entscheidungsunterstützungssystem zur Modellierung sowie Lösung von individualisierbaren Tourenplanungsproblemen präsentiert. Das flexible Tool ermöglicht die Abbildung von benutzerspezifischen Problemcharakteristika und die Umwandlung in ein entsprechendes Optimierungsmodell, sodass diverse Branchen bei der Routenplanung unterstützt werden können