Mode interactions in photonic crystal nano-cavity arrays

This thesis report is submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Electrical and Electronic Engineering, 2014.Cataloged from PDF version of thesis report.Includes bibliographical references (page 44-45).Over the last few decades Photonic Crystals (PhCs) have enjoyed immense attention from engineers, physicists and other interested parties due to its unique characteristics and its promise to revolutionize optical communication technologies. PhCs are made of dielectric materials periodic in one, two, or three dimensions and can exhibit photonic band gaps to certain frequencies. Therefore, it can be used to trap or guide “light” of certain frequencies within it. This thesis uses this very idea to construct a Photonic Crystal Slab (PCS) of finite thickness using photonic band gap maps, where air holes are introduced to create the periodicity. Cavity arrays are formed by manipulating the properties of certain air holes and the interactions between the modes within the cavity are analyzed. Two types of cavities are formed- one consisting of similar defects and one consisting of dissimilar defects. The software used for this thesis is Rsoft CAD Suit and the simulation tools used are BandSOLVE and FullWAVE.Efaz Karim, Ehsanul Alam Sabbir, Md. Raisul Islam ShantoB. Electrical and Electronic Engineerin

UGROŽENE VRSTE RIBA U SVIJETU: Rhinomugil corsula (Hamilton, 1822) (Mugiliformes: Mugilidae)

Mullet Rhinomugil corsula is a threatened fish of the family Mugilidae and used as food fish in Asian countries but its natural populations have declined due to over-exploitation and various ecological changes in its natural habitats leading to an alarming condition and deserving high conservation importance. This paper recommends measures for the conservation of the remnant isolated wild populations of R. corsula in Asian countries.Cipal, Rhinomugil corsula, je ugrožena vrsta iz porodice Mugilidae i koristi se kao hrana u azijskim zemljama. Prirodne populacije opadaju zbog pretjeranog iskorištavanja i raznih ekoloških promjena u njihovim prirodnim staništima što dovodi do zabrinjavajućeg stanja i zaslužuje veliku važnost u svrhu njihovog očuvanja. U radu se preporučuju mjere zaštite ostatka izoliranih divljih populacija R. corsula u azijskim zemljama

UGROŽENE VRSTE RIBA U SVIJETU: Heteropneustes fossilis (Bloch, 1794) (Siluriformes: Heteropneustidae)

The threatened stinging catfish Heteropneustes fossilis is a nutritionally valuable food in Asian countries but its natural populations have declined due to over-exploitation, habitat loss and pollution, thus deserving high conservation importance for the remaining isolated, wild populations of H. fossilis in Asian countries. The results would be useful for the protection of the presence of endemic species and sustainable fisheries in the lake.Ugroženi bodljasti som, Heteropneustes fossilis, je nutritivno vrijedna namirnica u azijskim zemljama, ali njegove prirodne populacije opadaju zbog pretjeranog iskorištavanja, gubitka staništa i zagađenja zbog kojih zaslužuje visoku važnost za zaštitu preostalih izoliranih, divljih populacija H. fossilis u azijskim zemljama

Group prenatal care experiences among pregnant women in a Bangladeshi community

BACKGROUND: Complications during pregnancy, childbirth, and following delivery remain significant challenges that contribute to maternal morbidity and mortality, thus affecting health systems worldwide. Group prenatal care (GPC) is an integrated approach incorporating peer support and health education that provides prenatal care in a group setting. The GPC approach was piloted in a district of Bangladesh to measure the feasibility and effectiveness of GPC compared to individual care. Understanding the experiences of women of receiving this grouped care approach is crucial to understand the perspectives, perception, and acceptability of the programme among mothers, which are lack in Bangladesh. The objective of the present study was to understand the core experiences and perspectives of mothers who participated in GPC sessions during their pregnancy period. METHODS: A qualitative research approach was used to understand the experiences of women receiving GPC. A total of 21 in-depth interviews were conducted in this study targeting pregnant mothers who attended all recommended GPC sessions. Face-to-face interviews were conducted by trained and experienced interviewers using a specific interview guideline to achieve detailed responses. Thematic analysis was conducted to analyse the data. RESULTS: Mothers appreciated receiving pregnancy care in group setting and expressed their preferences towards GPC compared to individual care. Themes included the comprehensiveness of GPC, prescheduled appointments and reduced waiting time, social gathering, coping with common discomforts, relationship with service providers, birth preparedness, and recommendations from participating mothers. The themes conveyed overall positive experiences of the participating mothers, with suggestions for further betterment of the programme. Nevertheless, the reported experiences of women involved in the study suggests that the inclusion of a specialist in group care, post-partum care, and family planning advice will be more beneficial in the GPC model. CONCLUSIONS: The overall experiences of the women in the present study suggest that GPC is helpful for them, and it is useful to reduce complications during pregnancy. The GPC model promises movement towards family-supported care, as explained by the participants

Development of microencapsulated phase change material for solar thermal energy storage

In this paper a novel microencapsulated phase change material (MF-3) has been developed and tested for solar assisted hot water storage systems. Even though the morphology of the sample was affected by the type of emulsifier used for fabrication it recorded the highest energy storage capacity of 126 kJ/kg with encapsulation efficiency of 97.4% as compared with other developed samples. For the purpose of assessing its thermal effectiveness it was theoretically evaluated in a compacted fixed bed TES unit and found to be capable of achieving a higher energy storage density as well as relatively smaller physical storage size than water based system. Despite the overall effective thermal conductivity being slightly less than water, its value was still about twice as high as most current PCM storage units. Experimental evaluation is therefore strongly encouraged

Numerical Simulation of Direct Expansion Solar-Assisted Heat Pump Water Heater Using Carbon Dioxide as Refrigerant

Compared to the conventional solar-assisted heat pump (SAHP) water heating system, a relatively more compact direct-expansion solar assisted heat pump (DX-SAHP) has been introduced, in which the solar collector acts as an evaporator. Details of the analytical studies of a CO2 transcritical cycle on SAHP water heating system are presented in this study. A numerical model has been developed to optimize the system design and operating parameters. The simulation model can predict the performance of the system COP, collector efficiency and heat capacity. An experimental prototype using the evacuated tube U-pipe solar collector utilized to verify the simulation results. The results show that both the solar radiation and ambient temperature have a significant impact on the DX-SAHP system's thermal performance. Year round performance showed that, theoretically, the system could achieve on an average, COP of 2 - 3.2, collector efficiency of 40 - 62% and water temperature to be about 43° - 56°C.Pakistan-US Science and Technology Cooperation Program, US Department of Stat

Defining the Crime of Enforced Disappearance in Conformity with International Criminal Law: a New Frontier for Bangladesh

Enforced disappearance is regarded as a state-sponsored heinous international crime and has recently emerged as a wide-spread issue in Bangladesh. The political opposition is currently the main target of forced disappearances, though apolitical citizens have also been targeted. Most of the incidents are unsolved and law enforcement agencies have repeatedly denied their involvement. Internationally, the UN Convention for the Protection of All Persons from Enforced Disappearance was opened for signature in 2007 and entered into force in 2010. The convention’s purpose is to criminalise enforced disappearances across the world and state parties are under an obligation to take necessary actions to stop their occurrence. Despite the cruel reality of forced disappearances in Bangladesh, no law has of yet been adopted to bring national criminal law in line with the convention. The right to life is nevertheless one of the key fundamental rights guaranteed under the Bangladeshi constitution which may be relevant in this context.  Forced disappearances have a disastrous impact on victim’s family as well as important societal implications. Bangladesh should, in this author’s opinion, ratify the convention and must reform national legislation to bring to an end state-sponsored crime. The scope of the issue may otherwise have tremendous consequences for the whole nation