Offsite Manufacturing: A Survey on the Current Status and Risks of Offsite Construction in Iran

This is the final published version. It first appeared at http://www.davidpublisher.com/index.php/Home/Article/index?id=109.html.Iran needs around 1.5 million residential homes to be constructed annually to answer its cumulative demand by 2025. Given the current situation of the Iranian construction industry, it seems almost impossible to achieve this objective by using traditional methods of construction alone. Offsite manufacturing (OSM) can potentially increase the housing output in Iran thanks to its advantages over traditional methods of construction. However, OSM imposes a different set of risks which should be studied in the Iranian context. This study aims to investigate the readiness of the Iranian construction industry if offsite methods were to be introduced to the country in large industrial scales. To this end, a questionnaire survey was conducted to identify the risks and required actions in order to achieve successful application of these methods. Several subjects including costs, practicality, design and construction processes, demand, governmental policies, technology, and sustainability issues were investigated as the core research areas. The results revealed that, considering the current situations, it would be highly risky to introduce offsite methods of construction to Iran. Research findings highlight some key areas including design and construction processes, economies of scale, governmental supports, and education, which should be addressed to mitigate the identified risks

Phased Array Systems in Silicon

Phased array systems, a special case of MIMO systems, take advantage of spatial directivity and array gain to increase spectral efficiency. Implementing a phased array system at high frequency in a commercial silicon process technology presents several challenges. This article focuses on the architectural and circuit-level trade-offs involved in the design of the first silicon-based fully integrated phased array system operating at 24 GHz. The details of some of the important circuit building blocks are also discussed. The measured results demonstrate the feasibility of using integrated phased arrays for wireless communication and vehicular radar applications at 24 GHz

The effects of air permeability, background ventilation and lifestyle on energy performance, indoor air quality and risk of condensation in domestic buildings

Effective and efficient ventilation is essential when improving energy performance and Indoor Air Quality (IAQ) of buildings. Reducing air permeability can considerably improve the energy performance of buildings; however, making the buildings more airtight may result in lower rates of natural ventilation which may in turn increase the risks of condensation and unacceptable IAQ. This study evaluates the effects of different air permeability rates, background ventilation and occupants’ lifestyles on the energy performance as well as the risk of condensation and CO2 concentration in domestic buildings. Dynamic computer simulations were conducted in EnergyPlus. Results indicated direct relations between the ventilation rates, energy performance and IAQ. Higher air permeability along with background ventilation resulted in considerably better IAQ while energy consumption increased by up to four times. Occupants’ lifestyles were identified as a major contributor to the risk of condensation.This is the final version. It was first published by MDPI at http://www.mdpi.com/2071-1050/7/4/4022

Daylighting and solar shading performances of an innovative automated reflective louvre system

Traditional windows, as the major source of daylight, have a common problem which is uneven distribution of daylight in the room. Several innovative daylighting systems such as light shelves, fixed and movable reflective louvres, reflective sills, prismatic glazing, light pipes, etc., have been developed to address this problem. This paper reports on a research programme that investigates retrofitted solutions to uneven distribution of daylight in deep-plan office buildings. The work presented here follows initial investigations into the design and applicability of an automated retrofitted panel thermal shutters which can also act as a sunshade and daylighting system. The system has a patented function which allows each shutter/louvre to be controlled and placed separately from other louvres. This study evaluates the effectiveness of the system when acting as a sunshade, light shelf, reflective louvre, and reflective sill under clear, overcast, and sunny sky conditions. According to the results, the system significantly improved daylight distribution and reduced the need for artificial lighting by 60%.This is the author accepted manuscript. The final version is available from Elsevier via http://www.sciencedirect.com/science/article/pii/S0378778814006355

Climate Resilient Low-Income Tropical Housing

This is the final version of the article. It first appeared from MDPI at http://dx.doi.org/10.3390/en9060468.Located in East Africa, Uganda is one of the most economically deprived countries that is likely to be dramatically affected by climate change. Over 50% of Ugandan families live in single-roomed overcrowded properties and over 60% of the country’s urban population live in slums. Moreover, the gradual shift towards relatively modern and low thermal resistance building materials, in addition to imminent thermal discomfort due to global warming, may considerably affect the health and wellbeing of low-income people, the majority of whom live in low quality homes with very little or no access to basic amenities. This paper evaluates the effects of various construction methods as well as refurbishment strategies on thermal comfort in low-income houses in Uganda. It is aimed at helping low-income populations adapt to climate changes by developing simple, effective and affordable refurbishment strategies that could easily be applied to existing buildings. Dynamic thermal simulations are conducted in EnergyPlus. The adaptive model defined in BS EN 15251 and CIBSE TM52 is used to evaluate the risk and extent of thermal discomfort. Roofing methods/materials are found to be the key factor in reducing/increasing the risk of overheating. According to the results, roof insulation, painting the roof with low solar absorptance materials and inclusion of false ceilings are, respectively, the most effective and practical refurbishment strategies in terms of improving thermal comfort in low-income houses in Uganda. All refurbishment strategies helped to pass Criterion 3 of CIBSE TM52, as an indicator of “future climate scenarios”, making low-income houses/populations more climate resilient.This document is an output from a research project “Energy and Low-Income Tropical Housing” co-funded by UK aid from the UK Department for International Development (DFID), the Engineering and Physical Science Research Council (EPSRC) and the Department for Energy and Climate Change (DECC), for the benefit of developing countries. The views expressed are not necessarily those of DFID, EPSRC or DECC

Complications leading to hospitalization due to consumption of anti-TB drugs in patients with tuberculosis in Gorgan, Iran (2007-12)

Background and Objective: Anti tuberculosis drugs therapy is the most effective method for controling the tuberculosis (TB). Early detection and appropriate treatment can prevent the TB-drug resistance. This study was carried out to determine the complications leading to hospitalization due to consumption of anti-TB drugs in patients with tuberculosis. Methods: In this descriptive-analytic study, 1550 records of patients with TB in urban and rural health centers of Gorgan, north of Iran were assessed during 2007-12. Checklist consists of demographic and clinical data for each patient was recorded in a questionare. Results: 44 cases experienced the complications of anti-TB drugs. 27 (61.4%) of cases with complications were women. 77.3% and 22.7% of patients affected with pulmonary and extra pulmonary tuberculosis,respectively. 38.6% of patients were diabetic. The hepatic complication was seen in 37 cases (84.1%). Skin and other complications were seen in 5 and 2 cases, respectively. There was not any relationship between drug complications and other disases. Conclusion: Hepatic damage is the most common complication leading to hospitalization in tuberculosis patients using anti-TB drugs. Keywords: Tuberculosis, Anti-TB drug, Live

3D mapping of young stars in the solar neighbourhood with Gaia DR2

We study the three dimensional arrangement of young stars in the solar neighbourhood using the second release of the Gaia mission (Gaia DR2) and we provide a new, original view of the spatial configuration of the star forming regions within 500 pc from the Sun. By smoothing the star distribution through a gaussian filter, we construct three dimensional density maps for early-type stars (upper-main sequence, UMS) and pre-main sequence (PMS) sources. The PMS and the UMS samples are selected through a combination of photometric and astrometric criteria. A side product of the analysis is a three dimensional, G-band extinction map, which we use to correct our colour-magnitude diagram for extinction and reddening. Both density maps show three prominent structures, Scorpius-Centaurus, Orion, and Vela. The PMS map shows a plethora of lower mass star forming regions, such as Taurus, Perseus, Cepheus, Cassiopeia, and Lacerta, which are less visible in the UMS map, due to the lack of large numbers of bright, early-type stars. We report the finding of a candidate new open cluster towards $l, b \sim 218.5^{\circ}, -2^{\circ}$, which could be related to the Orion star forming complex. We estimate ages for the PMS sample and we study the distribution of PMS stars as a function of their age. We find that younger stars cluster in dense, compact clumps, and are surrounded by older sources, whose distribution is instead more diffuse. The youngest groups that we find are mainly located in Scorpius-Centaurus, Orion, Vela, and Taurus. Cepheus, Cassiopeia, and Lacerta are instead more evolved and less numerous. Finally, we find that the three dimensional density maps show no evidence for the existence of the ring-like structure which is usually referred to as the Gould Belt.Comment: 17 pages, 17 figures, 6 appendixes; accepted for publication in A&A; image quality decreased to comply with the arXiv.org rules on file siz

A report about a case of Gestational trophoblastic tumor associated with ectopic pregnancy

مقدمه: تومور تروفوبلاستیک حاملگیGTT)) متعاقب حاملگی خارج رحمی یک رویداد بسیار نادر است. در این مقاله یک مورد مول مهاجم که از یک حاملگی خارج رحمی لوله‌ای نشأت گرفته بود معرفی می‌شود. گزارش مورد: بیمار خانم 26 ساله با حاملگی دوم و اولین حاملگی خارج رحمی (G2L1EP1) بود که به خاطر افزایش میزان هورمون گنادوتروپین جفتی((BHCG بعد از عمل حاملگی خارج رحمی (EP) به بیمارستان شهید بهشتی اصفهان ارجاع شد. درمان اولیه EP بیمار با عمل سالپنژکتومی بوده است. پیگیری پاتولوژی سالپنژکتومی مول مهاجم تشخیص داده شد که بیمار تحت دو دوره درمان با متوترکسات قرار گرفت و با توجه به گزارش توده در آدنکس راست در سونوگرافی یک نوبت لاپاراتومی ‌شد که باز هم تشخیص مول مهاجم بود. بنابراین بیمار تحت رژیم درمانی (etoposide methotrexate actinomycin D cyclophosphamide vincristine) EMA/CO قرار گرفت و نهایتاً با BHCG معادل 1 مرخص شد. نتیجه گیری: پیگیری عدد BHCG بعد از عمل جراحی EP هم برای تشخیص EP پا برجا و هم برای رد GTT بسیار مهم است هم چنین پیگیری جواب پاتولوژی اعمال جراحی در صورتی که از تشخیص نیز مطمئن هستیم ضرورت دارد

Optical properties of Born-Infeld-dilaton-Lifshitz holographic superconductors

In this paper, we first study the Lifshitz-dilaton holographic superconductors with nonlinear Born-Infeld (BI) gauge field and obtain the critical temperature of the system for different values of Lifshitz dynamical exponent, $z$, and nonlinear parameter $b$. We find that for fixed value of $b$, the critical temperature decreases with increasing $z$. This indicates that the increase of anisotropy between space and time prevents the phase transition. Also, for fixed value of $z$, the critical temperature decrease with increasing $b$. Then, we investigate the optical properties of ($2+1$) and ($3+1$)-dimensional BI-Lifshitz holographic superconductors in the the presence of dilaton field. We explore the refractive index of the system. For $z=1$ and $(2+1)$-dimensional holographic superconductor, we observe negative real part for permittivity $\textrm{Re}[\epsilon]$ as frequency $\omega$ decreases. Thus, in low frequency region our superconductor exhibit metamaterial property. This behaviour is independent of the nonlinear parameter and can be seen for either linear ($b=0$) and nonlinear ($b\neq 0$) electrodynamics. Interestingly, for ($3+1$)-dimensional Lifshitz-dilaton holographic superconductors, we observe metamaterial behavior neither in the presence of linear nor nonlinear electrodynamics.Comment: 11 pages, 9 figures (including subfigures), some references added in V