Studying the Effect of Tunnel Depth Variation on the Specific Energy of TBM, Case Study: KarajâTehran (Iran) Water Conveyance Tunnel

The tunnel-boring machine (TBM) is a common piece of equipment used in tunneling projects. For planning a mechanical excavation project, prediction of TBM performance and the specification of design elements such as required forces are critical. The specific energy of excavation (SE), i.e. drilling energy consumption per unit volume of rock mass, is a crucial parameter for performance prediction of a TBM. In this study, the effect of variation of tunnel depth on SE by considering the post-failure behavior of rock mass was investigated. Several new relations between SE and tunnel depth are proposed according to the statistical analysis obtained from Karaj"“Tehran Water Conveyance Tunnel real data. The results showed that there is a direct relation between both parameters and .A polynomial equations are proposed as the best expression of the correlation between these parameters

Maksimiziranje efikasnosti rudarenja u kamenolomu, prikaz studije slučaja

Nowadays, the dimension stone industry performs a crucial role in the world economy. Accordingly, dimension stone quarries’ importance grows due to their different applications in various construction, building, and decorative industries. Some issues threaten this industry and provide a financial risk that should be taken into account to make the smallest possible risk for investment. The presence of discontinuities in the rock mass has a key function as far as it concerns the overall quality of in situ rock blocks. It impacts the feasibility of dimension stone quarries and overall mine exploitation efficiency. Therefore, it is recommended to survey discontinuities and rock blocks and estimate the average geometry of a rock block, including the shape and size, before mining the benches to maximize mining exploitation efficiency and minimize waste ore production. This investigation aims to survey the discontinuities of the limestone quarry mine located in Josheghan, Iran, to determine and calculate rock blocks’ suitable geometry and an extraction’s direction for active mine benches. For this purpose, the scanline method was applied to survey discontinuities in seven active benches. 3DEC software was used to indicate discontinuities and model the rock blocks for all active benches. It was concluded that the benches’ cutting line make a 13.14 degree with the discontinuities main’s direction. The result of this study proved that by changing the direction of mining and extraction for active mine benches, the unnecessary waste production would decrease. The production rate with the recommended extraction direction will increase by about 1.13% compared to the current extraction direction, which makes 13.14 degrees with the discontinuities main’s direction. Currently, bench seven recorded the minimum production rate, which is 97.60; by applying the new extraction’s direction, it is predicted that this bench will achieve a 99.83 production rate. Consequently, it is concluded by improving the production rate, exploitation efficiency would increase considerably.Danas industrija arhitektonsko-građevnoga kamena zauzima važno mjesto u svjetskoj ekonomiji. Time raste i važnost kamenoloma. Postoje također i rizici povezani s takvim aktivnostima, posebice financijski. Nazočnost pukotina u stijenskoj masi može biti glavni rizik među njima, jer one ruše kvalitetu kamena, a time utječu na iskoristivost kamenoloma. Stoga je vrlo važno istražiti pukotine, stijenske blokove, njihovu geometriju i dimenzije prije otkopavanja, kako bi se podigla iskoristivost i smanjila količina jalovine. Ovdje su izučene pukotine u kamenolomu vapnenca u Josheghanu, Iran. Izračunana je odgovarajuća geometrija stijenskih blokova važna za eksploataciju. Metodom Scanline predviđene su pukotine na sedam radilišta, a paketom 3DEC za cijeli kamenolom. Izračunano je kako se smjer otkopavanja treba projicirati s otklonom od 13,14 stupnjeva u odnosu na glavni smjer pružanja pukotina. Dokazano je kako se promjenom smjera rudarenja povećava i udjel jalovine. No, rudarenjem pod navedenim kutom povećat će se pridobivanje za 1,13 % u usporedbi s trenutačnim. Na radilištu broj sedam zabilježena je minimalna proizvodnja od 97,60, a primjenom ovih rezultata očekuje se dosizanje vrijednosti od 99,83. Na taj način moguće je znatno povećati proizvodnju i iskoristivost

Microsatellite analysis of Damask rose (Rosa damascena Mill.) accessions from various regions in Iran reveals multiple genotypes

BACKGROUND: Damask roses (Rosa damascena Mill.) are mainly used for essential oil production. Previous studies have indicated that all production material in Bulgaria and Turkey consists of only one genotype. Nine polymorphic microsatellite markers were used to analyze the genetic diversity of 40 accessions of R. damascena collected across major and minor rose oil production areas in Iran. RESULTS: All microsatellite markers showed a high level of polymorphism (5–15 alleles per microsatellite marker, with an average of 9.11 alleles per locus). Cluster analysis of genetic similarities revealed that these microsatellites identified a total of nine different genotypes. The genotype from Isfahan province, which is the major production area, was by far the most common genotype (27/40 accessions). It was identical to the Bulgarian genotype. Other genotypes (each represented by 1–4 accessions) were collected from minor production areas in several provinces, notably in the mountainous Northwest of Iran. CONCLUSION: This is the first study that uncovered genetic diversity within Damask rose. Our results will guide new collection activities to establish larger collections and manage the Iranian Damask rose genetic resources. The genotypes identified here may be directly useful for breeding

The effect of oral tizanidine on postoperative pain relief after elective laparoscopic cholecystectomy

Background: Cholecystectomy is considered as the most important and relatively common postoperative pain control often begins in recovery room by using systemic narcotics that may have some side effects. The aim of this study is to evaluate the effect of premedication with oral tizanidine on pain relief after elective laparoscopic cholecystectomy. Materials and Methods: In this double-blinded clinical trial, 70 adults of American Society of Anesthesiologist physiologic state 1 and 2 scheduled for elective laparoscopic cholecystectomy under general anesthesia were studied and randomly divided in two study and control groups. Ninety minutes before the induction of anesthesia, patients received either 4 mg tizanidine (study group) orally in 50cc or the same volume of plain water as a placebo (control group). Then, the vital signs, pain intensity, duration of stay in recovery, and the analgesic consumption were measured and then compared in both groups during 24 h postoperatively. Results: There was no significant difference in patient characteristics, with respect to age, weight, gender, and duration of anesthesia and surgery between the groups (P > 0.05). The pain intensity, need for analgesic drugs (34.57 ± 8.88 mg vs. 101.86 ± 5.08 mg), and the duration of stay in recovery room (67.43 ± 1.59 min vs. 79.57 ± 5.48 min) were significantly lower in tizanidine group than that of the control group. Conclusion: Oral administration of 4 mg tizanidine before laparoscopic cholecystectomy reduces postoperative pain, opioid consumption, and consequence of the duration of stay in recovery room without any complication

Pre emptive analgesia for reducing pain after cholecystectomy: Oral tramadol vs. acetaminophen codeine

Background: Considering that protocols of postoperative pain management would be planned regarding the facilities of each center or region and the importance of its proper management to reduce its related complication and improve patient′s satisfaction, in this study we compared the effect of orally administrated tramadol and acetaminophen-codeine in this regard. Materials and Methods: In this prospective randomized double-blind clinical trial, 136 (68 in tramadol and 68 in acetaminophen codeine groups) ASA I and II patients scheduled for open cholecystectomy under general anaesthesia were enrolled. They randomly allocated to receive oral tramadol (50 mg capsule) or acetaminophen-codeine (325/10 mg) 1 hour before surgery. After surgery they evaluated for postoperative pain using VAS score, analgesic consumption and vomiting. Results: Mean of postoperative pain score during 24 hours after surgery was 2.1 ± 1.0 and 3.8 ± 2.0 in tramadol and acetaminophen-codeine groups, respectively (P < 0.05). Mean of analgesic consumption (morphine) during 24 hours after surgery was 6.2 ± 4.4 mg and 12.9 ± 5.7 mg in tramadol and acetaminophen-codeine groups, respectively (P < 0.05). Mean of vomiting during 24 hours after surgery was 1.2 ±0.9 and 0.4 ± 0.5 in tramadol and acetaminophen-codeine groups, respectively (P < 0.05). Conclusion: The findings of current study indicated that in lower dose of tramadol (50 mg) and acetaminophen/codeine (325 mg/10 mg) the analgesic effect of tramadol is better and its side effects are higher than acetaminophen/codeine, which limit its use for mentioned purpose. It seems that administration of each of studied agents it depends on patients′ tolerance and decision of the physician