Varastopaikkojen käytön optimointi ja keräilyn simulointi

Logistiikka-alalla toimitettavien artikkelien määrän ja kilpailun alati kasvaessa varastojen käyttökapasiteetin sekä toiminnan tehostamisen tarve on korostunut. Tutkielman aihe tulee käytännön ongelmasta, jossa varastopaikkojen sisällön optimointi asiakastilausten keräilijöiden kulkeman matkan suhteen on haastavaa. Tuotesijoitteluun suunniteltu optimointialgoritmi mahdollistaa valittujen parametrien mukaan optimoidun keräilyreitin suunnittelun. Kohdeyrityksen varasto ja sen keruualue ovat laajat kattaen satoja lavapaikkoja. Tutkimusprojektin tarkoituksena on toteuttaa lajittelualgoritmi, joka järjestää saatavilla olevat tuotteet annettujen parametrien mukaisesti niiden optimoiduille paikoille. Optimoinnin tulosten arvioimiseksi on vertailtava sitä, millaiset erot erilaisten tuotesijoitteluiden välillä käytännössä on. Arvioinnissa on otettu huomioon kolme erilaista tuotesijoittelua: satunnainen tuotesijoittelu, varaston nykyinen sijoittelu sekä optimoinnilla saavutettu sijoittelu. Arviointimenetelmänä käytetään simulointia, jota varten on toteutettu erillinen simulointialgoritmi. Projektissa toimitettiin onnistuneesti myös prosentuaaliset arviot siitä, kuinka merkittävä hyöty uudella sijoittelulla voidaan saavuttaa nykytilanteeseen verrattuna. Optimoinnilla saavutettu hyöty on myös onnistuttu muuttamaan potentiaalisiksi kustannussäästöiksi. Kuten tuloksista käy ilmi, optimoitu asettelu voi vähentää liikkumiseen käytettyä matkaa nykyiseen verrattuna jopa 15% ja täysin satunnaiseen asetteluun verrattuna jopa 27%. 15 prosenttiyksikön säästö kuljetussa matkassa on kustannussäästöiksi muunnettuna noin 4,5% keskimääräisen varaston kaikista operatiivisista kustannuksista. Tutkimuksen tulokset tukevat aiempia tutkimuksia volyymiperusteisen tuotesijoittelun tehokkuudesta. Algoritmin ehdottamaan sijoitteluun siirryttäessä voidaan saada jopa vastaavaa hyötyä, kuin siirryttäessä satunnaisesta järjestyksestä varaston nykyiseen sijoitteluun. Aiempaa tutkimustietoa hyödyntäen, tutkielma esittelee uudenlaisen lähestymistavan aiemmin tunnettuun ongelmaan.As the number of delivered articles and general competition continues to grow in the logistics sector, the efficiency of warehouse capacity utilization and operations is emphasized more than ever. The subject of this thesis comes from a practical problem where storage location content optimization turned out to be challenging in respect of the distance traveled by order collectors. The optimization algorithm designed for item placement enables the design of an optimized collection route according to selected parameters. The target company's warehouse and its order collection area are vast, covering hundreds of storage locations. This research project implements a sorting algorithm that arranges items into their optimized locations according to the given parameters. In order to evaluate the results of the optimization, it is necessary to compare the differences between the different item placements in practice. In the evaluation, three different item placements have been taken into account: random item placement, currently used placement, and placement achieved through optimization. The evaluation method used is simulation, for which a separate simulation algorithm has been implemented. The project also delivers percentage estimates of how significant the achieved benefits with the new item placement compared to the current situation can be. The benefits of optimization have also been converted into potential cost savings. The results show that an optimized item placement can reduce the distance traveled by up to 15% compared to the current one and by up to 27% compared to a random placement. The savings of 15% in the total distance traveled converted into cost savings is approximately 4.5% of the total operating costs of the average warehouse. The results of the study align with previous studies on the effectiveness of volume-based item placement. By switching over to the placement proposed by the algorithm, one can achieve even the same benefits as changing from a random order to the current placement. Utilizing previous research data, the thesis introduces a new approach to an already known problem

Comparison of outcome between nonoperative and operative treatment of medial epicondyle fractures

Background and purpose - Controversy exists regarding the optimal treatment for displaced medial epicondyle fractures. We compared the results of nonoperative and operative treatment and calculated the incidence of medial epicondyle fractures in the pediatric census population. Patients and methods - 112 children under 16 years old who sustained > 2 mm displaced fracture of the medial epicondyle were treated in our institution between 2014 and 2019. 80/83 patients with 81 non-incarcerated fractures were available for minimum 1-year follow-up. 41 fractures were treated with immobilization only, 40 by open reduction and internal fixation, according to the preference of the attending surgeon. Outcome was assessed at mean 2.6 years (1-6) from injury with different patient-reported outcome measures. Elbow stability, range of motion, grip strength, and distal sensation were registered in 74/80 patients. Incidence was calculated for 7- to 15-year-olds. Results - Nonoperatively treated children had less pain according to the PedsQL Pediatric Pain Questionnaire (3 vs. 15, p = 0.01) with better cosmetic outcome (VAS 95 vs. 87, p = 0.007). There was no statistically significant difference between the groups in respect of QuickDASH, PedsQL generic core scale, Mayo Elbow Performance Score, grip strength, carrying angle, elbow stability, or range of motion (p > 0.05). All 41 nonoperatively treated children returned to pre-injury sports; of the surgically treated 6/40 had to down-scale their sporting activities. The incidence of displaced (> 2 mm) fractures of the medial epicondyle in children aged 7-15 years was >= 3:100,000. Interpretation - Displaced fractures of the medial humeral epicondyle in children heal well with 3-4 weeks' immobilization. Open reduction and screw fixation does not improve outcome.Peer reviewe

Prevalence and treatment of hip displacement in children with cerebral palsy in Finland

Purpose: The aim was to study the prevalence of hip displacements, dislocations, and the hip surgeries performed in a Finnish cohort of children with cerebral palsy not followed up in a hip surveillance program and to compare these with previous studies performed in Northern European countries before and after the implementation of hip surveillance programs. Methods: A cross-sectional study. A cohort including 480 children with cerebral palsy, born during the period 2000-2018, not enrolled in a hip surveillance program. Migration percentages were recorded from hip radiographs, age at first hip surgery and type of surgery was extracted from medical records. In a separate analysis, the inclusion criteria were adapted to fit two studies analyzing hip dislocation and hip surgery in Sweden, Norway, and Scotland before and after the implementation of a hip surveillance program. Chi-square tests were used to assess differences in proportions between the groups. Results: In total, 286 children (60%) have had at least one hip radiograph. Of these, 10 (3.5%) developed hip dislocation, which is more than in children of countries with hip surveillance programs (Sweden 0.7%, Scotland 1.3%, p < 0.001). Initial surgery to prevent hip dislocation was performed at an older age (p < 0.001). Conclusion: Children with cerebral palsy in Finland not participating in a surveillance hip program were more likely to undergo hip surgery at an older age and to develop hip displacements and dislocations. The results support the effectiveness of surveillance programs to prevent hip dislocation in children with cerebral palsy.Peer reviewe