Dynamics of the Picking transformation on integer partitions

International audience This paper studies a conservative transformation defined on families of finite sets. It consists in removing one element from each set and adding a new set composed of the removed elements. This transformation is conservative in the sense that the union of all sets of the family always remains the same.We study the dynamical process obtained when iterating this deterministic transformation on a family of sets and we focus on the evolution of the cardinalities of the sets of the family. This point of view allows to consider the transformation as an application defined on the set of all partitions of a fixed integer (which is the total number of elements in the sets).We show that iterating this particular transformation always leads to a heterogeneous distribution of the cardinalities, where almost all integers within an interval are represented.We also tackle some issues concerning the structure of the transition graph which sums up the whole dynamics of this process for all partitions of a fixed integer.

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Late Triassic (Rhaetian) ophiuroids from Winterswijk, the Netherlands; with comments on the systematic position of Aplocoma (Echinodermata, Ophiolepididae)*

Zoosymposia ◽

10.11646/zoosymposia.7.1.15 ◽

2012 ◽

Vol 7 (1) ◽

pp. 163-172 ◽

Cited By ~ 2

Author(s):

BEN THUY ◽

ADIËL A. KLOMPMAKER ◽

JOHN W.M. JAGT

Keyword(s):

The Netherlands ◽

Middle Triassic ◽

Systematic Position ◽

Point Of View ◽

Type Material ◽

Late Triassic ◽

The Family ◽

Salinity Levels ◽

Bottom Waters ◽

Almost All

An ophiuroid assemblage from Rhaetian dark shales in a subrosion pipe (or sinkhole) penetrating middle Triassic (Muschelkalk) strata, and, outside the subrosion pipe, disconcordantly overlying middle Triassic strata, east of Winterswijk, the Netherlands, is described, discussed and assessed taxonomically. The material consists of nearly intact and articulated as well as wholly disintegrated skeletons, almost all of which are pyritised, yet so well preserved that the diagnostic characters could be studied in detail. All specimens belong to Aplocoma agassizi (von Münster, 1839). Examination of the type material of Ophiolepis damesii Wright, 1874 (housed at the Roemer and Pelizäus Museum in Hildesheim, Germany, collection numbers NKP 7821 to NKP 7828) from Rhaetian strata at Hildesheim, Germany, comparable to those exposed at Winterswijk, has revealed that O. damesii is to be considered a nomen dubium due to the insufficient preservation of the type material. Based on the present lot, which documents the first Triassic echinoderms from the well-known Winterswijk quarry complex, we suggest that the genus Aplocoma is best reassigned to the family Ophiolepididae, in proximity to the extant Ophiozonella, and that the family Aplocomidae is to be suppressed. From a palaeoecological point of view, the Winterswijk assemblage illustrates preservation under the influence of storms in an otherwise very quiet environment; it is here interpreted as a monospecific assemblage amidst an oligospecific bivalve community in a near-coastal, shallow, muddy setting with fluctuating or low salinity levels and/or dysoxic bottom waters.

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A symbolic projection of Langton's Ant

Discrete Mathematics & Theoretical Computer Science ◽

10.46298/dmtcs.2312 ◽

2003 ◽

Vol DMTCS Proceedings vol. AB,... (Proceedings) ◽

Author(s):

Anahi Gajardo

Keyword(s):

Point Of View ◽

Algebraic Characterization ◽

Transition Rule ◽

Regular Graphs ◽

New Approach ◽

The Family ◽

International Audience ◽

Topological Dynamical Systems

International audience The Langton's ant is studied from the point of view of topological dynamical systems. A new approach which associate a subshift to the system is proposed.The transition rule is generalized to the family of bi-regular graphs $\Gamma(k,d)$ and the dependence of the dynamical system on $k$ and $d$ is analyzed. A classification of the $\Gamma (k,d)$ graphs based on the dynamical properties of the subshift is established. Also a hierarchy is defined on the graphs through the subset relation of the respective subshifts. The analysis are worked out by establishing an algebraic characterization of the forbidden words of the subshift.

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Analisis Perbandingan Manajemen Keuangan Ojek Online Dan Ojek Reguler Studi Kasus Kecamatan Duren Sawit Jakarta Timur

Liquidity ◽

10.32546/lq.v7i1.173 ◽

2018 ◽

Vol 7 (1) ◽

pp. 41-52

Author(s):

M. Koesmawan ◽

Darwin Erhandy ◽

Dede Dahlan

Keyword(s):

Financial Management ◽

Average Income ◽

Savings And Loans ◽

Financial Difficulties ◽

The Family ◽

Family Finances ◽

The Subject ◽

Almost All

In order to meet the needs of living which consists of primary as well as secondary needs, human can work in either a formal or an informal job. One of the informal jobs that is became the subject of this research was to become an ojek driver. Ojek is a ranting motorcycle. Revenue of ojek drivers, accordingly, should be well managed following the concept of financial management. This research was conducted for the driver of the online motorcycle drivers as well as the regular motorcycle drivers they are called “The Ojek”. Ojek’s location is in Kecamatan (subdistrict) Duren Sawit, East Jakarta with 70 drivers of ojeks. The online ojeks earn an average of Rp 100,000 per day, can save Rp 11,000 to 21,000 per day, while, the regular ojek has an average income per day slightly lower amounted to Rp 78,500, this kind of ojeks generally have other businesses and always record the outflow of theirs money. Both the online and regular ojeks feel a tight competition in getting passengers, but their income can help the family finances and both ojeks want a cooperative especially savings and loans, especially to overcome the urgent financial difficulties. Almost all rivers, do not dare to borrow money. They are afraid of can not refund the money as scheduled.

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Hyperbolastic Models from a Stochastic Differential Equation Point of View

Mathematics ◽

10.3390/math9161835 ◽

2021 ◽

Vol 9 (16) ◽

pp. 1835

Author(s):

Antonio Barrera ◽

Patricia Román-Román ◽

Francisco Torres-Ruiz

Keyword(s):

Differential Equation ◽

Simulated Data ◽

Real Data ◽

Point Of View ◽

Likelihood Method ◽

Numerical Resolution ◽

The Family ◽

The Common ◽

Linear Differential ◽

Mean Function

A joint and unified vision of stochastic diffusion models associated with the family of hyperbolastic curves is presented. The motivation behind this approach stems from the fact that all hyperbolastic curves verify a linear differential equation of the Malthusian type. By virtue of this, and by adding a multiplicative noise to said ordinary differential equation, a diffusion process may be associated with each curve whose mean function is said curve. The inference in the resulting processes is presented jointly, as well as the strategies developed to obtain the initial solutions necessary for the numerical resolution of the system of equations resulting from the application of the maximum likelihood method. The common perspective presented is especially useful for the implementation of the necessary procedures for fitting the models to real data. Some examples based on simulated data support the suitability of the development described in the present paper.

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How ethical challenges of covert observations can be met in practice

Research Ethics ◽

10.1177/17470161211008218 ◽

2021 ◽

pp. 174701612110082

Author(s):

Nicole Podschuweit

Keyword(s):

Social Research ◽

Role Playing ◽

Great Distance ◽

Point Of View ◽

Ethical Challenges ◽

Research Subjects ◽

Written Information ◽

Ethical Debate ◽

The People ◽

Almost All

This paper aims to bring into the ethical debate on covert research two aspects that are neglected to date: the perspective of the research subjects and the special responsibility of investigators towards their observers. Both aspects are falling behind, especially in quantitative social research. From a methodological point of view, quantitative forms of covert observation involve a great distance between the researcher and the research subjects. When human observers are involved, the focus is usually on the reliable application of the measuring instrument. Therefore, herein, a quantitative study is used as an example to show how the protection needs of both the observed persons and the observers can be met in practice. The study involved 40 student observers who covertly captured everyday conversations in real-world settings (e.g. in cafés or trains) by a highly standardised observation scheme. The study suggests that the anonymity of the research subjects and their trust in the observers are crucial for their subsequent consent. However, many participants showed only little or even no interest in the written information they were provided. Further, this study strongly emphasises how mentally stressful covert observations are to the observers. Almost all observers were worried in advance that the people they were observing would prematurely blow their cover and confront them. Role-playing and in-depth discussions in teams are good strategies to alleviate such and other fears and to prepare student assistants well for their demanding work in the field.

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Two new species of the genus Syngastes (Copepoda, Harpacticoida, Tegastidae) from South Korea

Crustaceana ◽

10.1163/15685403-00003533 ◽

2016 ◽

Vol 89 (4) ◽

pp. 431-458 ◽

Cited By ~ 1

Author(s):

Jong Guk Kim ◽

Tae Won Jung ◽

Jong Guk Kim ◽

Tae Won Jung ◽

...

Keyword(s):

New Species ◽

South Korea ◽

First Record ◽

Exopodal Segment ◽

Key To Species ◽

Korean Waters ◽

The Family ◽

Two New Species ◽

Almost All

Herein two new species of the genusSyngastesMonard, 1924 are described from South Korea, with detailed descriptions and illustrations. Both new copepods,Syngastesmulticavussp. nov. andS. pseudofoveatussp. nov., have two inner setae on the first exopodal segment of P2 and P3.Syngastesmulticavussp. nov. most closely resemblesS. gibbosusBartsch, 1999 reported from Australia, as they both have a five-segmented antennule in the female. However,Syngastesmulticavussp. nov. has a rounded body outline instead of the gibbose outline observed inS. gibbosus.Syngastespseudofoveatussp. nov. resemblesS. foveatusBartsch, 1994 in almost all aspects. However, they differ clearly in the number of setae on the first exopodal segment of P2 and P3. We also provide a key to species of the genusSyngastesworldwide. The present study is the first record of the family Tegastidae in Korean waters.

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Resolving the Lourinia armata (Claus, 1866) complex with remarks on the monophyletic status of Louriniidae, Monard 1927 (Copepoda: Harpacticoida)

Zootaxa ◽

10.11646/zootaxa.5051.1.15 ◽

2021 ◽

Vol 5051 (1) ◽

pp. 346-386

Author(s):

SÜPHAN KARAYTUĞ ◽

SERDAR SAK ◽

ALP ALPER ◽

SERDAR SÖNMEZ

Keyword(s):

Comparative Evaluation ◽

Species Complex ◽

Detailed Examination ◽

The Other ◽

Phylogenetic Position ◽

Nicobar Island ◽

Other Hand ◽

The Family ◽

Close Relationship ◽

Almost All

An attempt was made to test if Lourinia armata (Claus, 1866)—as it is currently diagnosed—represents a species complex. Detailed examination and comparisons of several specimens collected from different localities suggest that L. armata indeed represents a complex of four closely related morphospecies that can be differentiated from one another by only detailed observations. One of the four species is identified as Lourinia aff. armata and the other three species are described as new to science and named as Lourinia wellsi sp. nov., L. gocmeni sp. nov., and L. aldabraensis sp. nov. Detailed review of previous species records indicates that the genus Lourinia Wilson, 1924 is distributed worldwide. Ceyloniella nicobarica Sewell, 1940, originally described from Nicobar Island and previously considered a junior subjective synonym of L. armata is reinstated as Lourinia nicobarica (Sewell, 1940) comb. nov. on the basis of the unique paddle-shaped caudal ramus seta V. It is postulated that almost all of these records are unreliable in terms of representing true Lourinia aff. armata described herein. On the other hand, the comparative evaluation of the illustrations and descriptions in the published literature indicates the presence of several new species waiting to be discovered in the genus Lourinia. It has been determined that, according to updated modern keys, the recent inclusion of the monotypic genus Archeolourinia Corgosinho & Schizas, 2013 in the Louriniidae is not justified since Archeolourinia shermani Corgosinho & Schizas, 2013 does not belong to this family but should be assigned to the Canthocamptidae. On the other hand, it has been argued that the exact phylogenetic position of the Louriniidae still remains problematic since none of the diagnostic characters supports the monophyly of the family within the Oligoarthra. It has also been argued that the close relationship between Louriniidae and Canthocamptidae is supported since both families share the homologous sexual dimorphism (apophysis) on P3 endopod. The most important characteristic that can possibly be used to define Louriniidae is the reduction of maxilliped.

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THE FAMILY HISTORY OF SPINA BIFIDA CYSTICA

PEDIATRICS ◽

10.1542/peds.35.4.589 ◽

1965 ◽

Vol 35 (4) ◽

pp. 589-595

Author(s):

John Lorber

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Spina Bifida ◽

Index Case ◽

Progressive Increase ◽

Point Of View ◽

The Family ◽

History Of ◽

The Central Nervous System ◽

Spina Bifida Cystica

1. The family histories of 722 infants who were born with spina bifida cystica were studied. 2. The index cases were referred for surgical treatment and were not selected in any way from the genetic point of view. 3. Intensive inquiries were made to obtain a complete family pedigree, including a prospective follow-up of siblings born after the index case. 4. Of 1,256 siblings 85 or 6.8% had gross malformation of the central nervous system: spina bifida cystica in 54, anencephaly in 22, and uncomplicated hydrocephalus in 9. 5. Of 306 children born after the index case 25 (8%) or 1 in 12 were affected. 6. There was a progressive increase in multiple cases in the family with increasing family size. In sibships of five or more, multiple cases occurred in 24.1%. 7. In 118 families cases of gross malformation of the central nervous system were known to have occurred among members of the family other than siblings. Cases occurred in three generations. 8. It is possible that spina bifida cystica might be a recessively inherited condition.

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THE PATIENT BOY—A POPULAR LESSON, READ TO CHILDREN IN THE 1820'S

PEDIATRICS ◽

10.1542/peds.43.4.526 ◽

1969 ◽

Vol 43 (4) ◽

pp. 526-526

Author(s):

T. E. C.

Keyword(s):

The Family ◽

Almost All

The story below depicts a favorite subject of those who wrote for children in the early days of our country. The inebriated father leading his family inexorably into destitution by his intemperance is counterbalanced by a son who holds the family together. During the last century many children cried over this and similar stories. The Patient Boy There was a journeyman bricklayer in this town, a good workman, but a very drunken idle fellow; he spent at the dram shop almost all he earned, and left his wife and children to take care of themselves; to get food and clothes as they could. They might all have starved, but for the eldest son, whom his father had brought up to help him at his work; and who was so industrious and attentive, that being now at the age of thirteen or fourteen, he was able to earn pretty good wages, every penny of which that he could keep out of his father's hands, he brought to his mother. When the brute of a father came home drunk, cursing and swearing, and in such an ill humour that his mother, and the rest of the children, durst not come near him for fear of a beating, this good lad (Tom was his name) kept close to him, to pacify him, and get him quietly to bed. His mother looked upon Tom as the support of the family, and loved him dearly. It happened one day, Tom in climbing up a high ladder, with a load of mortar on his head, missed his hold, and fell down to the bottom, on a heap of bricks and rubbish.

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Beleweniswêreld van die straatkind in Hillbrow

Curationis ◽

10.4102/curationis.v21i1.612 ◽

1998 ◽

Vol 21 (1) ◽

Author(s):

R. Hatting ◽

M. Poggenpoel ◽

C.P.H. Myburgh

Keyword(s):

Qualitative Study ◽

Living Environment ◽

Point Of View ◽

Child Life ◽

Street Child ◽

Negative Effects ◽

Educational Psychologist ◽

The Family ◽

Developmental Opportunities ◽

Gaining Insight

The street child that is driven by circumstances to live outside the supportive structure of the family, is on his own. He doesn’t have the educational developmental opportunities that children who grow up in families and societies do. He finds himself in a unique educational and living environment. From an educational psychologist’s point of view, this environment is abnormal. It is therefore a great challenge for the educational psychologist to try and avoid or resolve negative effects of the child's living environment. An exploratory-, descriptive-, contextual- and qualitative study was done, with the aim of gaining insight and understanding into the life of the street child in Hillbrow as well as his experiences of his situation. The results obtained from the interviews were placed in four categories. These categories are: The street child’s continuous struggle to survive, his need for a “normal child life” , his inability to accept responsibility and the presence of a normative awareness within the street child. In conclusion it is clear that the experiential world of the street child is multi-facetted. In general it appears that the street child has many limitations and difficulties which he experiences, and that input by an educational psychologist can have meaningful influence in his life.

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