56 research outputs found

    Evolutionary dynamic optimisation of airport security lane schedules

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Reducing costs whilst maintaining passenger satisfaction is an important problem for airports. One area this can be applied is the security lane checks at the airport. However, reducing costs through reducing lane openings typically increases queue length and hence passenger dissatisfaction. This paper demonstrates that evolutionary methods can be used to optimise airport security lane schedules such that passenger dissatisfaction and staffing costs can be minimised. However, it is shown that these schedules typically over-fit the forecasts of passenger arrivals at security such that in actuality significant passenger delays can occur with deviations from the forecast. Consequently, this paper further demonstrates that dynamic evolutionary re-optimisation of these schedules can significantly mitigate this over-fitting problem with much reduced passenger delays

    Robustness and evolutionary dynamic optimisation of airport security schedules

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    Reducing security lane operations whilst minimising passenger waiting times in unforseen circumstances is important for airports. Evolutionary methods can design optimised schedules but these tend to over-fit passenger arrival forecasts resulting in lengthy waiting times for unforeseen events. Dynamic re-optimisation can mitigate for this issue but security lane schedules are an example of a constrained problem due to the human element preventing major modifications. This paper postulates that for dynamic re-optimisation to be more effective in constrained circumstances consideration of schedule robustness is required. To reduce over-fitting a simple methodology for evolving more robust schedules is investigated. Random delays are introduced into forecasts of passenger arrivals to better reflect actuality and a range of these randomly perturbed forecasts are used to evaluate schedules. These steps reduced passenger waiting times for actual events for both static and dynamic policies with minimal increases in security operations

    Maternal age, education level and migration: Socioeconomic determinants for smoking during pregnancy in a field study from Turkey

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    WOS: 000279909900003PubMed ID: 20534133Background: Smoking during pregnancy has been associated with socioeconomic determinants and it is recognized as the most important preventable risk factor for an unsuccessful pregnancy outcome. Turkey has national data on the prevalance of smoking during pregnancy; however there is no data on the characteristics of the high-risk population. This is a field study that aims to identify socioeconomic determinants for smoking during pregnancy as well as differentiating the daily and occasional smokers. Method: Cross sectional study was conducted among women with 0-5 year old children living in the area served by Primary Health Care Center (PHCC) in Burhaniye, Turkey. Face-to-face interviews were conducted by the researchers during January-March 2008 at the home of the participants with 83.7% response rate (n = 256). The relation of "smoking during pregnacy" and "daily smoking during pregnancy" with the independent variables was determined with chi(2) tests. Women's age, educational level, number of previous births, place of origin, migration, partner's educational level, poverty, perceived income, social class were evaluated. Statistical significance was achieved when the p value was less than 0.05. The variables in relation with the dependent variables in the chi(2) tests were included in the forward-stepwise logistic analysis. Results: Prevalance of smoking during pregnancy was 22.7%. The majority (74.1%) were daily smokers. Young mothers (< 20), low educated women and migrants were at increased risk for smoking during pregnancy. Low education and being a migrant were risk factors for daily consumption (p < 0.05). Conclusions: Systematic attention should be paid to socioeconomic determinants in smoking for pregnant women, especially in countries like Turkey with high rates of infant and mother mortality and substantial health inequalities. Young mothers (< 20), low educated women and migrants are important groups to focus on

    Totally laparoscopic versus laparoscopy-assisted distal gastrectomy: the KLASS-07: a randomized controlled trial

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    BACKGROUNDS: Strong evidence is lacking as no confirmatory randomized controlled trials (RCTs) have compared the efficacy of totally laparoscopic distal gastrectomy (TLDG) with laparoscopy-assisted distal gastrectomy (LADG). The authors performed an RCT to confirm if TLDG is different from LADG. METHODS: The KLASS-07 trial is a multi-centre, open-label, parallel-group, phase III, RCT of 442 patients with clinical stage I gastric cancer. Patients were enroled from 21 cancer care centres in South Korea between January 2018 and September 2020 and randomized to undergo TLDG or LADG using blocked randomization with a 1:1 allocation ratio, stratified by the participating investigators. Patients were treated through R0 resections by TLDG or LADG as the full analysis set of the KLASS-07 trial. The primary endpoint was morbidity within postoperative day 30, and the secondary endpoint was quality of life (QoL) for 1 year. This trial is registered at ClinicalTrials.gov (NCT03393182). RESULTS: Four hundred forty-two patients were randomized (222 to TLDG, 220 to LADG), and 422 patients were included in the pure analysis (213 and 209, respectively). The overall complication rate did not differ between the two groups (TLDG vs. LADG: 12.2% vs. 17.2%). However, TLDG provided less postoperative ileus and pulmonary complications than LADG (0.9% vs. 5.7%, P= 0.006; and 0.5% vs. 4.3%, P= 0.035, respectively). The QoL was better after TLDG than after LADG regarding emotional functioning at 6 months, pain at 3 months, anxiety at 3 and 6 months, and body image at 3 and 6 months (all P&lt; 0.05). However, these QoL differences were resolved at 1 year. CONCLUSIONS: The KLASS-07 trial confirmed that TLDG is not different from LADG in terms of postoperative complications but has the advantages to reduce ileus and pulmonary complications. TLDG can be a good option to offer better QoL in terms of pain, body image, emotion, and anxiety at 3-6 months

    A Ciphertext-Policy Attribute-Based Encryption Based on Multi-valued Decision Diagram

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    Part 8: Business Intelligence and SecurityInternational audienceCiphertext-policy attribute-based encryption (CP-ABE) is a kind of asymmetric encryption which is widely used in cyber-physical system and Internet of Things. In CP-ABE, access structure is an important component affecting the efficiency and performance greatly in several stages, such as encryption stage, key generation stage, decryption stage. However, the existing CP-ABE schemes have low efficiency because of the application of traditional access structures. In order to alleviate the aforementioned problems, this paper proposes a brand-new access structure based on multi-valued decision diagram (MDD). According to this access structure, we design a new CP-ABE scheme which performs better than many current schemes. First, our scheme supports multi-valued attributes directly. Second, the size of secret key is constant because it bears no relationship to the number of attributes. Third, the time complexity of decryption stage is O(1)

    Prognostic Role of Adjuvant Chemotherapy in Node-Negative (N0), Triple-Negative (TN), Medullary Breast Cancer (MBC) in the Korean Population

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    Despite the favorable prognosis for medullary breast cancer (MBC), the guidelines for the use of adjuvant chemotherapy for MBC have not been clearly established. This study investigated the prognostic role of adjuvant chemotherapy in Korean patients with node-negative (N0), triple-negative (TN) MBC patients.We included data from 252 patients with N0 TN MBC, obtained from the Korean Breast Cancer Registry database. Patients were categorized as those who did not undergo adjuvant chemotherapy (group I) or those who did (group II). Clinicopathological characteristics, breast cancer-specific survival (BCSS), and overall survival (OS) were compared between the groups. In addition, a subgroup analysis for survival based on tumor size was conducted.A total of 252 N0 TN MBC patients with tumor sizes >1 cm who were diagnosed between April 1997 and March 2011 were enrolled. The median age was 44.95 years (range, 25-72 years), and the median follow-up period was 93.94 months (range, 23-195 months). Overall, the BCSS and OS in group II (97.3% and 97.3%, respectively) were significantly better compared with those in group I (89.2% and 86.2%, respectively). In the subgroup analysis, in patients with tumors >2 cm in size, those in group II had significant better BCSS and OS (97.5% and 97.5%, respectively) compared with those in group I (78.3% and 73.9%, respectively). In contrast in those with tumors 1-2 cm in size, there were no significant differences in BCSS and OS between the groups (both 97.1% for group I, and 95.2% and 92.9%, respectively for group II). Multivariate analysis revealed that adjuvant chemotherapy significantly improved BCSS (P = 0.009) and OS (P = 0.007), but only for patients with larger tumors (>2 cm).In patients with N0 TN MBC, adjuvant chemotherapy had a significant clinical survival benefit, but only in those with tumors >2 cm
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