scholarly journals Solving a Real-Life Distributor’s Pallet Loading Problem

2021 ◽  
Vol 26 (3) ◽  
pp. 53
Author(s):  
Mauro Dell’Amico ◽  
Matteo Magnani
Keyword(s):  
Bin Packing ◽  
Real Life ◽  
Second Phase ◽  
Pallet Loading ◽  
Minimum Number ◽  
Loading Problem ◽  
The Difference ◽  
Two Phases ◽  
The Stability ◽  
Selection Of

We consider the distributor’s pallet loading problem where a set of different boxes are packed on the smallest number of pallets by satisfying a given set of constraints. In particular, we refer to a real-life environment where each pallet is loaded with a set of layers made of boxes, and both a stability constraint and a compression constraint must be respected. The stability requirement imposes the following: (a) to load at level k+1 a layer with total area (i.e., the sum of the bottom faces’ area of the boxes present in the layer) not exceeding α times the area of the layer of level k (where α≥1), and (b) to limit with a given threshold the difference between the highest and the lowest box of a layer. The compression constraint defines the maximum weight that each layer k can sustain; hence, the total weight of the layers loaded over k must not exceed that value. Some stability and compression constraints are considered in other works, but to our knowledge, none are defined as faced in a real-life problem. We present a matheuristic approach which works in two phases. In the first, a number of layers are defined using classical 2D bin packing algorithms, applied to a smart selection of boxes. In the second phase, the layers are packed on the minimum number of pallets by means of a specialized MILP model solved with Gurobi. Computational experiments on real-life instances are used to assess the effectiveness of the algorithm.

scholarly journals Self-Adaptive K-Means Based on a Covering Algorithm

Complexity ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Yiwen Zhang ◽  
Yuanyuan Zhou ◽  
Xing Guo ◽  
Jintao Wu ◽  
Qiang He ◽  
...  
Keyword(s):  
Large Scale ◽  
Clustering Algorithm ◽  
Real Data ◽  
Second Phase ◽  
Data Sets ◽  
Number Of Clusters ◽  
Large Scale Data ◽  
Long Time ◽  
Two Phases ◽  
Selection Of

The K-means algorithm is one of the ten classic algorithms in the area of data mining and has been studied by researchers in numerous fields for a long time. However, the value of the clustering number k in the K-means algorithm is not always easy to be determined, and the selection of the initial centers is vulnerable to outliers. This paper proposes an improved K-means clustering algorithm called the covering K-means algorithm (C-K-means). The C-K-means algorithm can not only acquire efficient and accurate clustering results but also self-adaptively provide a reasonable numbers of clusters based on the data features. It includes two phases: the initialization of the covering algorithm (CA) and the Lloyd iteration of the K-means. The first phase executes the CA. CA self-organizes and recognizes the number of clusters k based on the similarities in the data, and it requires neither the number of clusters to be prespecified nor the initial centers to be manually selected. Therefore, it has a “blind” feature, that is, k is not preselected. The second phase performs the Lloyd iteration based on the results of the first phase. The C-K-means algorithm combines the advantages of CA and K-means. Experiments are carried out on the Spark platform, and the results verify the good scalability of the C-K-means algorithm. This algorithm can effectively solve the problem of large-scale data clustering. Extensive experiments on real data sets show that the accuracy and efficiency of the C-K-means algorithm outperforms the existing algorithms under both sequential and parallel conditions.

scholarly journals Estudio de la enseñanza de ecosistemas amazónicos a través de la metodología de aprendizaje basada en la resolución de problemas (ABRP)

2018 ◽  
Vol 22 ◽  
pp. 9
Author(s):  
Carlos Henrique Nascimento ◽  
Ires Paula de Andrade Miranda
Keyword(s):  
Problem Solving ◽  
Data Collection ◽  
Primary School ◽  
School Environment ◽  
Problem Based Learning ◽  
Problem Formulation ◽  
Teaching Methodology ◽  
Second Phase ◽  
Two Phases ◽  
Selection Of

The purpose was to analyze the Problem-based learning (PBL) as a methodological alternative for primary school that favor learning about Amazonian ecosystems. This research is descriptive with a qualitative-quantitative approach. The study was carried out with students from the 9th year of primary school. The teaching methodology based on the PBL was applied in two phases: In the first phase, a test of previous conceptions was carried out in order to know the perception of the students on topics related to some units of landscapes of the Amazonian ecosystems. The second phase consisted of the implementation of the learning methodology in the school environment. Four different phases were established in the application: i) selection of topics; ii) problem formulation; iii) problem solving; iv) synthesis and evaluation. The data collection instruments used were: preconceptions test and skills chart. The results showed that after the application of the ABRP methodology, the cognitive recognition of the Amazonian ecosystems can be perceived in the students, reaching additional goals that the PCN establish.

scholarly journals Biphasic pattern in the effect of severe measles infection; the difference between additive and multiplicative scale

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nhat Thanh Hoang Le ◽  
Nhan Thi Ho ◽  
Bryan Grenfell ◽  
Stephen Baker ◽  
Ronald B. Geskus
Keyword(s):  
Infectious Diseases ◽  
Hospital Admission ◽  
Measles Virus ◽  
Hospital Admissions ◽  
Admission Rate ◽  
Second Phase ◽  
Before And After ◽  
The Difference ◽  
Two Phases ◽  
Additive Scale

Abstract Background Infection with measles virus (MeV) causes immunosuppression and increased susceptibility to other infectious diseases. Only few studies reported a duration of immunosuppression, with varying results. We investigated the effect of immunosuppression on the incidence of hospital admissions for infectious diseases in Vietnamese children. Methods We used retrospective data (2005 to 2015; N = 4419) from the two pediatric hospitals in Ho Chi Minh City, Vietnam. We compared the age-specific incidence of hospital admission for infectious diseases before and after hospitalization for measles. We fitted a Poisson regression model that included gender, current age, and time since measles to obtain a multiplicative effect measure. Estimates were transformed to the additive scale. Results We observed two phases in the incidence of hospital admission after measles. The first phase started with a fourfold increased rate of admissions during the first month after measles, dropping to a level quite comparable to children of the same age before measles. In the second phase, lasting until at least 6 years after measles, the admission rate decreased further, with values up to 20 times lower than in children of the same age before measles. However, on the additive scale the effect size in the second phase was much smaller than in the first phase. Conclusion The first phase highlights the public health benefits of measles vaccination by preventing measles and immune amnesia. The beneficial second phase is interesting, but its strength strongly depends on the scale. It suggests a complicated interaction between MeV infection and the host immunity.

Microstructural Instability in Mosi2/Sic Nanolayers

1997 ◽  
Vol 3 (S2) ◽  
pp. 399-400
Author(s):  
Y.C. Lu ◽  
H. Kung ◽  
J-P Hirvonen ◽  
T.R. Jervis ◽  
M. Nastasi ◽  
...  
Keyword(s):  
High Temperature ◽  
Ion Irradiation ◽  
High Temperature Strength ◽  
Second Phase ◽  
Microstructural Stability ◽  
Factors Affecting ◽  
Structural Applications ◽  
Thermal Compatibility ◽  
Two Phases ◽  
The Stability

Thin film multilayers have been the focus of extensive studies recently due to the interesting properties they exhibit. Since the improvement in properties can be attributed directly to the unique nanoscale microstructures, it is essential to understand the factors affecting the microstructural stability in these nanolayer structures. The intermetallic compound, MoSi2, despite its superior oxidation resistance and high melting point, suffers from inadequate high temperature strength and low temperature ductility, properties which hinder its high temperature structural applications [1]. SiC is a potential second phase reinforcement due to its high temperature strength and thermal compatibility with MoSi2. The addition of SiC in a nanolayered configuration has been shown to exhibit significant increase in hardness after annealing [2]. It has also been shown that when annealed above 900°C, the layers break down and grain growth sets in, with a significant decrease in hardness and. Due to the lack of a thermochemical driving force, the two phases remain separate at all temperatures investigated. In this study, the stability of the MoSi2/SiC nanolayers structure under ion irradiation has been investigated.

scholarly journals PARADIGMA MANAJEMEN SUMBER DAYA MANUSIA BERBASIS SPIRITUAL (SPIRITUAL BASED HUMAN RESOURCES MANAGEMENT) TERHADAP KORPORASI

2015 ◽  
Vol 6 (1) ◽  
Author(s):  
HADI PERISTIWO
Keyword(s):  
Human Resources ◽  
Human Resources Management ◽  
Real Life ◽  
Second Phase ◽  
Internal Motivation ◽  
Resources Management ◽  
Self Actualization ◽  
Two Phases ◽  
Corporation Management ◽  
The Individual

Abstract. Spiritual Based Human Resources Management Paradigm to Corporation. Management comes into the world as a basic necessity on the individual relationship in the society. Every activity always have main aim to be reached in the present and future. Crystallization of management thinking begins on a certain time to develop and expand experiences renewal. The existence of the company becomes main source of people’s live. The potential of the Muslim community into company resources (employee) can be utilized to increase the employee’s performance religious. But, the reality still happen today that the employee’s attitude far from religious behaviour. For the example: still a lot of woman employee which undress well as order as religion instruction, furthermore the behaviour and lifestyle become secular and materialistic. Spiritual Based Human Resources Management is one of coherent concept between modern management and spiritual's values. There are two phases of Developing spiritualitas's meaning, first on spiritual aspect developing (inner growth's phase) and the second phase is manifestation of the first phase results in everyday real life. Furthermore, self-actualization based on internal motivation will be reflected as a framework of spiritual based human resources management, including personal behavior of people in work, business or organization. Abstrak. Paradigma Manajemen Sumber Daya Manusia Berbasis Spiritual (Spiritual Based Human Resources Management) Terhadap Korporasi. Manajemen lahir sebagai tuntunan perlunya pengaturan hubungan antara individu dalam lingkungan masyarakat serta pada dasarnya setiap aktifitas atau kegiatan selalu memiliki tujuan yang ingin dicapai. Kristalisasi pemikiran manajemen mulai berkembang  pada kurun waktu tertentu dan berkembang serta mengalami berbagai pembaruan. Keberadaan perusahaan menjadi sumber utama kehidupan  masyarakat.  Potensi masyarakat muslim yang menjadi sumber daya perusahaan (karyawan) diharapkan dapat digunakan untuk meningkatkan kinerja karyawannya secara religius. Akan tetapi kenyataan yang terjadi adalah masih banyak perilaku karyawan perusahaan yang  tidak religius, misalnya: masih banyak karyawan perusahaan khususnya wanita yang menggunakan pakaian yang tidak menutup aurat (pakaian mini), perilaku maupun pandangan hidup karyawan yang sekuler serta materialistis. Manajemen sumber daya manusia berbasis spiritual (Spiritual Based Human Resources Management) adalah sebuah konsep terpadu antara manajemen modern dengan nilai-nilai spiritual. Makna spiritualitas berkembang sedemikian rupa, spiritualitas dilihat sebagai sebuah proses dalam dua fase perkembangan, pertama pada fase perkembangan aspek batin (inner growth) dan kedua pada fase manifestasi hasil batin tersebut dalam kehidupan sehari-hari di dunia nyata. Dalam kerangka manajemen sumber daya manusia berbasis spiritual, perilaku orang dalam bekerja, berbisnis atau berorganisasi adalah aktualisasi diri yang bersumber pada  internal motivation.

scholarly journals TWO PHASES IN THE DEVELOPMENT OF HEDWIG CONRAD-MARTIUS’ ONTOLOGICAL INVESTIGATION ON HUMAN BEING AND LIVING THINGS

2021 ◽  
Vol 10 (2) ◽  
pp. 398-424
Author(s):  
SIMONA BERTOLINI ◽  
Keyword(s):  
Structure Change ◽  
Second Phase ◽  
Human Being ◽  
Human Knowledge ◽  
Living Things ◽  
Ontological Categories ◽  
Biological Ontology ◽  
The Difference ◽  
Two Phases ◽  
Theoretical Results

Interest in the ontological constitution of living beings (with particular reference to the human being) characterizes the whole development of Hedwig Conrad-Martius’ philosophy. Several works written by the philosopher over the years deal with both the phenomenological description and the ontological foundation of the difference between plants, animals, and humans. Specifically, the ontological structure of the human being is investigated as a layered structure which presupposes those of plants and animals while overcoming them in a more complex and spiritual unity, on which human freedom and human knowledge depend. Although this topic maintains a crucial role in Conrad-Martius’ thought, the way the philosopher addresses it and the theoretical results of her phenomenological-ontological inquiry about it do not remain unchanged. Indeed, the ontological structure at the basis of phenomenal differences as well as the metaphysical foundations of this structure change over the decades. This paper aims at distinguishing between two phases, characterized by different ontological categories, through which Conrad-Martius’ anthropology and biological ontology develop. In the first phase, at the beginning of the twenties (precisely in her work Metaphysical Dialogues), the essential differences between plants, animals, and humans are explained with reference to a vital origin preceding the constitution of reality; to describe it Conrad-Martius employs terms such as “abyss” and “under-earthly realm.” In the second phase, exemplified by some writings published in the forties and the fifties, the reference to such a dimension disappears and the eidetic variety within the living world, including human specificity, is exclusively traced back to the finalistic substantiation of essences in the natural beings.

The Pallet Loading Problem: Three-dimensional bin packing with practical constraints

2020 ◽  
Vol 287 (3) ◽  
pp. 1062-1074 ◽  
Author(s):  
Fatma Gzara ◽  
Samir Elhedhli ◽  
Burak C. Yildiz
Keyword(s):  
Bin Packing ◽  
Three Dimensional ◽  
Pallet Loading ◽  
Loading Problem ◽  
Practical Constraints

Accuracy assessment of surgical planning and three-dimensional-printed patient-specific guides for orthopaedic osteotomies

2017 ◽  
Vol 231 (6) ◽  
pp. 499-508 ◽  
Author(s):  
Gwen Sys ◽  
Hannelore Eykens ◽  
Gerlinde Lenaerts ◽  
Felix Shumelinsky ◽  
Cedric Robbrecht ◽  
...  
Keyword(s):  
Accuracy Assessment ◽  
Average Distance ◽  
Three Dimensional ◽  
Patient Specific ◽  
Second Phase ◽  
Experimental Setup ◽  
Operative Planning ◽  
The Difference ◽  
Two Phases ◽  
Improved Accuracy

This study analyses the accuracy of three-dimensional pre-operative planning and patient-specific guides for orthopaedic osteotomies. To this end, patient-specific guides were compared to the classical freehand method in an experimental setup with saw bones in two phases. In the first phase, the effect of guide design and oscillating versus reciprocating saws was analysed. The difference between target and performed cuts was quantified by the average distance deviation and average angular deviations in the sagittal and coronal planes for the different osteotomies. The results indicated that for one model osteotomy, the use of guides resulted in a more accurate cut when compared to the freehand technique. Reciprocating saws and slot guides improved accuracy in all planes, while oscillating saws and open guides lead to larger deviations from the planned cut. In the second phase, the accuracy of transfer of the planning to the surgical field with slot guides and a reciprocating saw was assessed and compared to the classical planning and freehand cutting method. The pre-operative plan was transferred with high accuracy. Three-dimensional-printed patient-specific guides improve the accuracy of osteotomies and bony resections in an experimental setup compared to conventional freehand methods. The improved accuracy is related to (1) a detailed and qualitative pre-operative plan and (2) an accurate transfer of the planning to the operation room with patient-specific guides by an accurate guidance of the surgical tools to perform the desired cuts.

Working Characteristics of a DICI Engine by Using Water Emulsion Biodiesel Fuels

2014 ◽  
Vol 592-594 ◽  
pp. 1847-1851 ◽  
Author(s):  
Muthe Srinivasa Rao ◽  
R.B. Anand
Keyword(s):  
Second Phase ◽  
Exhaust Gas ◽  
Water Emulsion ◽  
Performance And Emission ◽  
Ci Engine ◽  
Hc Emissions ◽  
Two Phases ◽  
Smoke Opacity ◽  
The Stability ◽  
Biodiesel Fuels

The present experimental investigation is carried out to establish the stability, compatibility and feasibility of working characteristics of DICI engine by using Jatropha biodiesel, Pongamia biodiesel and related water emulsion biodiesels. Experiments are carried out in two phases on a DICI engine test rig which includes CI engine, electric loading device, exhaust gas analysers, and a data-acquisition system. The performance and emission characteristics of the engine are studied by using neat diesel, Jatropha and Pongamia biodiesel in the first phase, and similar experiments are conducted by water – biodiesel emulsion fuels in the second phase. The water–biodiesel emulsion fuels are prepared with the aid of a mechanical homogenizer in the proportion of 10% water, 88 % biodiesel, and 2 % surfactants (by volume). Sequentially, the stability characteristics of water–biodiesel emulsion fuels are analyzed. The results indicated that slight improvement in BTE and BSFC for water – biodiesel emulsion fuels compared to biodiesel fuels. The exhaust emissions of NOx and smoke opacity were decreased for the water biodiesel emulsion fuels as compared to respective neat biodiesel and neat diesel. CO & unburned HC emissions were slightly increased for the water biodiesel emulsion fuels compared to respective neat biodiesels and less than of neat diesel.

Visual Processing of Contour Patterns under Conditions of Inattentional Blindness

2012 ◽  
Vol 24 (2) ◽  
pp. 287-303 ◽  
Author(s):  
Michael A. Pitts ◽  
Antígona Martínez ◽  
Steven A. Hillyard
Keyword(s):  
Visual Processing ◽  
Visual Awareness ◽  
Inattentional Blindness ◽  
Second Phase ◽  
Third Phase ◽  
Random Arrays ◽  
Visual Contour ◽  
The Difference ◽  
Two Phases ◽  
Task Irrelevant

An inattentional blindness paradigm was adapted to measure ERPs elicited by visual contour patterns that were or were not consciously perceived. In the first phase of the experiment, subjects performed an attentionally demanding task while task-irrelevant line segments formed square-shaped patterns or random configurations. After the square patterns had been presented 240 times, subjects' awareness of these patterns was assessed. More than half of all subjects, when queried, failed to notice the square patterns and were thus considered inattentionally blind during this first phase. In the second phase of the experiment, the task and stimuli were the same, but following this phase, all of the subjects reported having seen the patterns. ERPs recorded over the occipital pole differed in amplitude from 220 to 260 msec for the pattern stimuli compared with the random arrays regardless of whether subjects were aware of the patterns. At subsequent latencies (300–340 msec) however, ERPs over bilateral occipital-parietal areas differed between patterns and random arrays only when subjects were aware of the patterns. Finally, in a third phase of the experiment, subjects viewed the same stimuli, but the task was altered so that the patterns became task relevant. Here, the same two difference components were evident but were followed by a series of additional components that were absent in the first two phases of the experiment. We hypothesize that the ERP difference at 220–260 msec reflects neural activity associated with automatic contour integration whereas the difference at 300–340 msec reflects visual awareness, both of which are dissociable from task-related postperceptual processing.

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