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Searching for Neutralisers of Energetic Organic Compounds: A Theoretical Approach from the Perspective of Quantum Chemistry
Get PDFNeutralising energetic molecules is a valuable approach to minimize the risks of unpredictable explosions and associated tragic events. Quantum chemical methods offer highly efficient and effective tools for studying these compounds. The main objective of this dissertation is to quantify the impact of intermolecular interactions on the sensitivity of energetic compounds. Concerning the cyclic compounds RDX (1,3,5- trinitro-1,3,5-triazinane) and HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocane), a quantitative analysis with MEP evidenced anomalies arising from the marked depletion of negative charge distribution. The EDA-NOCV results reveal that the electrostatic and orbital contributions are the dominant factors driving the assembly of the M = {Ti, Zr, Hf}-based complexes. The chemical nature of the O· · ·M = {Ti, Zr, Hf} bonding has been investigated by using the QTAIM theory. Additionally, the topological properties of the N–NO2 trigger bonds were quantified before and after the O· · ·M interaction.
These intermolecular interactions strengthens the trigger bonds, revealing an increased stability to decomposition. The IRI-based analysis was carried out to further investigate the electronic properties of group 4 transition metals in coordination environments. With regard to the aliphatic compound FOX-7 (1,1-diamino-2,2-nitroethylene), we examined three types of interactions: oxygen and nitrogen from a nitro group interacting with the metal atom, as well as nitrogen from an amino group interacting with the same metal atom. The local chemical reactivity of FOX-7 was elucidated
through a quantitative study of MEP. Results derived from QTAIM showed that the C–NO2 bonds are influenced by the O· · ·M = {Ti, Zr, Hf} bonding. Furthermore, this interaction rules the complex formation when a nitro group interacts with MMCs. The interaction energies calculated by EDA-NOCV revealed that the (H2N)2C=C(NO2)- (O)NO· · · Cp2MCH+3 complexes are significantly more structurally stable (by about 21.8 kcal/mol) than the (O2N)2C=C(NH2)-H2N· · · Cp2MCH+3 complexes. This work is crucial to validate the proposal of using MMCs (metallocene methyl cations) as a neutraliser of energetic molecules
Élaboration d'un outil d’aide à la conception pour une optimisation climatique et énergétique des bâtiments résidentiels dans un climat désertique. L’exemple du sud algérien
Get PDFThe mastery of energy consumption in the residential sector aims to improve the quality
of life while reducing the impact of carbon footprint on the environment. Unfortunately, the
neglect of environmental specifics has led to the abusive and irrational use of energy resources
on a global scale. In Algeria, the electrical consumption of the residential sector currently
accounts for 40% of the total national electricity consumption. This consumption is primarily
directed towards artificial lighting, heating, and air conditioning in households. The southern
regions of Algeria, characterized by a very hot and arid climate, clearly illustrate the extent of
environmental and energy problems resulting from practices and malfunctions in the production
of residential buildings.
Since independence, constructions in the south no longer meet the extremely rigorous
climatic conditions of the summer season and fail to provide minimal thermal comfort
conditions. As a result, residents are forced to resort to mechanical heating and air conditioning
systems to maintain a certain level of comfort, leading to increasing costs every year. To reduce
energy bills and ensure optimal climatic comfort, it is imperative to intervene at the level of
architectural design.
This study seeks to explore this issue in relation to residential architecture in southern
Algeria, using the city of El Oued as a case study. Indeed, like other regions in southern Algeria,
dwellings in the Souf region pose a thermal comfort problem and present a challenge in the
design process of housing projects. However, the vernacular architecture of the Souf region
represents an exemplary model of both bioclimatic and sustainable architecture, highlighting
the harmonious adaptation of buildings to their climatic context. This integration is based on
passive strategies that ensure a healthy indoor thermal comfort while avoiding the use of
mechanical systems. These passive methods, including building orientation, nighttime natural
ventilation, the window-to-wall ratio, as well as construction materials, dictate the adaptation
of constructions to local conditions. Nowadays, contemporary architecture has ignored these
passive strategies, resulting in the creation of energy-intensive residential buildings that depend
mainly on heating and mechanical air conditioning systems.
VI
To minimize energy consumption in residential buildings located in desert climates, it
is necessary to proceed with optimization that considers both climatic and energy aspects. In
this perspective, this study was conducted to develop an environmental assistance guide based
on specific climatic, social, and economic conditions. This tool draws inspiration from
vernacular passive strategies to alleviate discomfort conditions generated by contemporary
constructions. Through the development of an integrated approach to the conceptual process,
this tool is intended for architects, providing them with the means to use it from the sketch
phase. It serves as a set of knowledge and skills specifically designed for architects, guiding
them practically and simplified throughout the design process, with the ultimate goal of creating
efficient and functional living spaces, offering optimal thermal comfort and increased wellbeing for occupants
Study of sorption cooling systems adapted to hot climates: use of available energy resources in the Saharan regions
Get PDFIn this work, we propose three configurations for the cooling tower, including one suggested
as a technical solution to enhance the thermal performance of the solar sorption cooling system
during scorching outdoor air temperatures. These configurations are based on a combination of the
dry cooling tower (DCT) with one or more sorption systems, where these systems are defined as a
spray water system (SWS), a direct evaporative cooler (DEC), and a ground heat exchanger
(GHE). The combined system may incorporate more than one sorption system in the same
configuration. A case study is presented concerning an adsorption device primarily driven by solar
energy in the dry and hot climate of Biskra, Algeria. The developed methodology was validated,
and a good agreement was found between numerical simulations and experimental results obtained
from the literature. It was concluded that the coupling of the cooling tower with one or more
sorption systems is an effective solution in hot and arid regions
مظاهر سوء المعاملة الأسرية للطفل في الجزائر كما تدركها الأمهات - دراسة ميدانية بوحدات الكشف والمتابعة بدائرة سيدي عقبة نموذجا -
Get PDFكسائر البحوث النفسية والاجتماعية تستوجب هدف لإجراء البحث، وكان هدف دراستنا التعرف على مظاهر سوء المعاملة الأسرية للطفل في الجزائر كما تدركها الأمهات المترددات على وحدات الكشف والمتابعة للتلاميذ.
من أجل ذلك كانت تساؤلاتنا على الشكل التالي:
- ما ترتيب مظاهر سوء المعاملة الأسرية التي يتعرض لها الطفل في الجزائر كما تدركها الأمهات المترددات على وحدات الكشف والمتابعة ؟
- هل توجد فروق ذات دلالة احصائية بين وجهات نظر الأمهات المترددات على وحدات الكشف والمتابعة للتلاميذ في سوء المعاملة الأسرية للطفل تعزى لمتغير السن ؟
- هل توجد فروق ذات دلالة احصائية بين وجهات نظر الأمهات المترددات على وحدات الكشف والمتابعة للتلاميذ في سوء المعاملة الأسرية للطفل تعزى لمتغير عدد الأبناء ؟
- هل توجد فروق ذات دلالة احصائية بين وجهات نظر الامهات المترددات على وحدات الكشف والمتابعة للتلاميذ حول مظاهر سوء المعاملة الأسرية للطفل في الجزائر تعزى لمتغير المستوى التعليمي؟
- هل توجد فروق ذات دلالة احصائية بين وجهات نظر الامهات المترددات على وحدات الكشف والمتابعة للتلاميذ حول مظاهر سوء المعاملة الأسرية للطفل في الجزائر تعزى لمتغير الدخل الشهري؟
وللكشف عن ذلك اعتمدنا على المنهج الوصفي الاستكشافي حيث تم استخدام أدوات بحث متمثلة في مقابلة نصف موجهة في الدراسة الاستطلاعية مع 05 أمهات يترددن على وحدة الكشف والمتابعة للتلاميذ لتكون منطلقا لتصميم استبيان سوء المعاملة الأسرية للطفل للدراسة الأساسية حيث وزع على 110 أم مترددة على وحدات الكشف والمتابعة بدائرة سيدي عقبة.
دلت النتائج في الختام على أن:
- هناك تفاوت في ترتيب مظاهر سوء المعاملة الاسرية التي يتعرض لها الطفل في الجزائر كما تدركها الأمهات المترددات على وحدات الكشف والمتابعة.
- لا توجد فروق بين وجهات نظر الأمهات المترددات على وحدات الكشف والمتابعة للتلاميذ في سوء المعاملة الأسرية للطفل تعزى لمتغيري السن وعدد الأطفال.
- هناك فروق بين وجهات نظر الأمهات المترددات على وحدات الكشف والمتابعة للتلاميذ في سوء المعاملة الأسرية للطفل تبعا لمتغيري المستوى التعليمي والدخل الشهري.
: Summary
As well as other psychological and social research requires a goal to conduct research, and the goal of our study to identify the manifestations of family abuse of children in Algeria, as recognized by mothers on the units of detection and follow-up to students.
For this, our questions were as follows:
- What is the order of manifestations of family ill-treatment that the child is exposed to in Algeria, as are the mothers aware of the detection and follow-up units?
- Are there statistically significant differences between the views of mothers on the units of detection and follow-up of students in child abuse of the child due to the age variable?
- Are there statistically significant differences between the views of mothers on the units of detection and follow-up of students in child abuse of the child due to the variable number of children?
- Are there statistically significant differences between the views of mothers on the units of detection and follow-up of students about the manifestations of child abuse in Algeria due to the variable level of education?
- Are there statistically significant differences between the views of mothers on the units of detection and follow-up to students about the manifestations of child abuse in Algeria due to the variable monthly income?
To find out, we relied on the exploratory descriptive approach. The research tools used in the semi-structured interview were used in the survey with 50 mothers who frequented the unit of detection and follow-up of the students to be the starting point for designing the questionnaire of the child abuse of the basic study. And the follow-up of the Sir Aqba circle.
The results indicated in conclusion that:
- There is a disparity in the order of the manifestations of domestic abuse of the child in Algeria, as recognized by mothers who frequented the units of detection and follow-up.
- There are no differences between the views of mothers on the units of detection and follow-up of students in child abuse of the family due to the age variables and the number of children.
- There are differences between the views of mothers on the units of detection and follow-up to students in the abuse of the family of the child depending on the variables of educational level and monthly income
ثقافة اللباس لدى الشباب الجزائري التحولات والخلفيات الثقافية دراسة انثروبولوجية بمنطقة تبسة
Get PDFRESUME :
Notre étude de terrain sur « la culture vestimentaire chez les jeunes algériens de la ville de Bir Al-Ater » a révélé un ensemble de résultats importants. L’étude a montré que les jeunes algériens considèrent qu’il est important de planifier avant d’acheter des vêtements, car la majorité de l’échantillon a souligné l’importance de la planification dans le processus d’achat, et la plupart des participants préparent un budget avant de commencer. Lors des achats, il existe une classification de leurs vêtements dans leur garde-robe en fonction de leurs besoins. De plus, les jeunes préfèrent acheter des vêtements en fin de saison pour profiter des remises disponibles, alors qu’un tiers de l’échantillon n’accorde pas beaucoup d’attention à ce processus. Cependant, il existe un pourcentage important de jeunes qui préfèrent acheter des vêtements. Au début de la saison, même malgré la hausse des prix, l’étude a également indiqué l’influence de leurs amis et des médias sur le choix des vêtements, bien qu’un certain pourcentage de jeunes estime que les marques ne sont pas importantes pour eux. En général, il a été constaté que les perceptions et les comportements des jeunes concernant l’habillement sont affectés par de nombreux facteurs qui les entourent, ce qui rend ce sujet susceptible de se développer et de se différencier.
ABSTRACT :
Our field study on “the culture of dress among Algerian youth in the city of Bir Al-Ater” revealed a set of important results. The study showed that Algerian youth consider planning before purchasing clothes to be important, as the majority of the sample stressed the importance of planning in the purchasing process, and most participants prepare a budget before starting. In shopping, there is a classification of their clothes in their closet according to their needs. In addition, young people prefer to buy clothes at the end of the season to take advantage of the available discounts, while not much attention is given to this process by a third of the sample. However, there is a large percentage of young people who prefer to buy clothes. At the beginning of the season, even despite the rise in prices, the study also indicated the influence of their friends and the media on choosing clothes, although there is a certain percentage of young people who believe that brands are not important to them. In general, it was found that the perceptions and behaviors of young people regarding Dress is affected by many factors surrounding them, which makes this topic susceptible to development and difference
Contribution à l’optimisation de la fertilisation phospho-azotée en sol salé et calcaire
Get PDFLes sols de l’Algérie sont généralement pauvres en azote et posent toujours le problème de la
disponibilité du phosphore assimilable surtout en régions arides, où l’on trouve également le
problème de la salinité qui s’accompagne souvent de la présence de calcaire. Le présent
travail vise à examiner l’optimisation de la fertilisation phospho-azotée en condition saline et
carbonatée par l’utilisation de différents types, formes et doses d’engrais azotés et phosphatés.
On tentera de: i) trouver la meilleure formule qui combine la forme et la dose d’engrais ; ii)
Connaître l’effet sur l’augmentation des rendements et la disponibilité des éléments nutritifs
pour la culture de blé dur. Les engrais utilisés sont : l’Urée (46%), le super phosphate triple
TSP (46%), le super phosphate simple SSP (20%), le Nitrate de Potassium KNO 3 (13%), le
Monoammonium phosphate MAP(12%, 61%), le NPK(15%,15%,15%), le
NPK(20%,20%,20%), le NPK(13%,40%,13%), le NPK(30%,10%,10%), le
NPK(4%,20%,25%) combinés avec trois doses (D1=150U N et P 2 O 5 /ha, D2=200U N et
P 2 O 5 /ha et D3=250U N et P 2 O 5 /ha). Les résultats obtenus montrent que la fertilisation
phospho-azotée a un effet très important sur les paramètres étudiés. En effet on constate que
les meilleurs résultats sont obtenus par les engrais composés, la hauteur des plantes: (HP
(montaison)=MAP (250U/ha), HP (récolte)= MAP et NPK (15%,15%,15%) (250U/ha) et
(KNO 3 -SSP) (150U/ha)), le rendement et ses composantes: (Nombre des grains/épi (NG/E)=
NPK (13%,40%,13%) (250U/ha), poids de mille grains (PMG)= NPK (4%, 20%, 25%)
(250U/ha), rendement en grains (RG)= NPK (13%,40%,13%) (250U/ha) et NPK
(15%,15%,15%) (150U/ha), rendement en paille (RP)= NPK (15%,15%,15%) (250U/ha) et
(KNO 3 -SSP) (150U/ha)). Tous les types d’engrais réagissent positivement à la teneur des
feuilles en azote (N), et le NPK(4%,20%,25%) (250 U/ha) a donné le meilleur teneur des
feuilles en phosphore. Cependant la teneur la plus élevée des grains en azote et en phosphore
est obtenue par les engrais simples, N= (Urée-SSP) avec la dose (200 et 250 U/ha), et P 2 O 5 =
(Urée-TSP) avec la dose (150U/ha). La fertilisation phospho-azotée joue un rôle très
important dans la richesse du sol en phosphore assimilable et en azote total dans les
conditions saline et carbonaté. Les meilleures teneurs du sol en P 2 O 5 sont obtenues par le
traitement NPK(20%,20%,20%) (250U/ha) au stade fin tallage et par le traitement
(KNO 3 _TSP) (250 U/ha) au stade récolte. Les meilleures teneurs en (N) total sont obtenues
par le traitement (Urée_TSP) (250U/ha) au stade fin tallage et récoltes. On peut conclure que
l’effet de la fertilisation phospho-azotée en condition saline et carbonatée varie en fonction du
type et de la dose d’engrais
On Fractional Brownian Motion with Application to Risk Sensitive
Get PDFThis thesis expands upon Pontryagin’s stochastic maximum principle to accommodate systems modeled by fractional Brownian motion. we present two research topics. The FIRrst centers on an optimal control problem wherein the state equation is driven by fractional Brownian motion, and the cost functional follows a risk-neutral type. Initially, we present the optimal control problem and its underlying dynamics, followed by the convex perturbation method in which the set of admissible controls is convex. Subsequently, we establish both optimality conditions for this model. Finally, we demonstrate our …ndings through a linear quadratic problem, solving the associated Riccati type equation.
The second topic focuses on characterizing optimal control problems within a risk-sensitive framework. The system dynamics are de…ned using only the backward stochastic di¤erential equations. However, the performance criterion is distinct; instead of directly minimizing costs, we aim to minimize a convex disutility function of the cost. As an initial step, we elucidate the relationship between riskneutral and risk-sensitive loss functionals. Next, we establish the equivalence between expected exponential utility and quadratic backward stochastic di¤erential equations.
Further, we reformulate the risk-sensitive problem into a standard risk-neutral one by introducing an auxiliary term and demonstrate the determination of the adjoint equation. Thus, we derive the stochastic maximum principle using a standard application of risk-neutral results. Finally, we apply these concepts to a control problem with linear quadratic risk sensitivity
Malliavin Smoothness of Solutions of BSDE and Applications
Get PDFthis thesis studies two different topics in the stochastic systems fields: The solutions’ Malliavin regularity and control theory. The first is related to the Malliavin smoothness of the solutions of a specific type of quadratic backward stochastic differential equation (chapter 1) and the convergence of their numerical approximating schemes (chapter 2). The second topic refers to optimal control problems for stochastic systems with non-smooth coefficients (chapter 3). Chapter one focuses on the Lq(q ≥ 2)-existence and uniqueness of the solutions of the one-dimensional quadratic backward stochastic differential equation (Q-BSDEs for short) and their properties. The Lp-Hölder continuity of the solutions for any (q > 4 and 2 ≤ p < 2q) are established and some important results concerning the smoothness of the solution of Q-BSDEs are presented. These findings are obtained based on the connection between the underlying Q-BSDEs and the related Lipschitz BSDE (L-BSDEs for short). The natural tools are the Malliavin calculus and the so-called Zvonkin’s transformation.
Chapter two uses some existing results on L-BSDEs literature to construct and study the convergence rates of different types of numerical schemes for the solution of Q-BSDE in different cases: explicit and implicit. Those schemes are not completely discrete with respect to the z-variable. However, under some restrictive conditions, a completely discrete scheme” is introduced and studied. The last chapter investigates the necessary and sufficient optimality conditions for a class of controlled stochastic differential equations where the coefficients are merely Lipschitz continuous in the state variable but not necessarily differentiable everywhere
Modélisation Non-Linéaire de Certaine Série Chronologique Périodique
Get PDFCette thèse se concentre sur l’étude des modèles GARCH pour les séries financières, en particulier ceux avec des coefficients variant périodiquement dans le temps. Elle explore diverses extensions de ces modèles, notamment logGARCH(1, 1), le modèle GARCH de valeur absolue et les modèles GARCH seuil bilinéaires, en mettant l’accent sur leurs propriétés théoriques, leurs méthodes d’estimation et leurs applications empiriques. La recherche offre des perspectives sur les solutions stationnaires, les techniques d’estimation et la pertinence pratique, démontrant leur efficacité dans la modélisation des taux de change du dinar algérien par rapport aux principales devises
