ارزیابی پاسخ صوتی و ارتعاشی اتاق بتنی با به‌کارگیری ورق‌های سفت‎شده با تسمه‌های فولادی بر روی دیواره‎ی بازشوی فولادی زیر بار انفجار Investigating the acoustical and vibrational response of stiffened steel plate opening wall in a RC room subject to blast 1 1 نیاز به درک چگونگی ساکت‌سازی سازه‌ای در طراحی‌ها، توجه مهندسین به تولید و تراگسیل صدا از سازه‌های مرتعش را به همراه داشته است. در این پژوهش با به‌کارگیری نرم‌افزار آباکوس، اثر چیدمان‎های گوناگون سفت‌کننده در یک وجه از اتاق بر روی پاسخ صوتی و ارتعاشی اتاق زیر اثر انفجار بررسی شده‌ است. هم‌چنین، تحلیل بسامدی برای بررسی افت تراگسیل صدا در گستره‎ی‎ بسامد زیر اثر میدان پخشیده نوفه‎ی سفید، برای هر یک از چیدمان‎ها انجام شده ‎است. سه گونه سفت‌کننده‎ی قطری، ضربدری و موازی در تحلیل‌ها به‌کار رفته‌اند. یافته‌ها نشان می‌دهند که گونه‎ی سفت‌کننده تأثیر چشم‎گیری بر روی پاسخ ارتعاشی سامانه ندارد و تنها در حالتی که سفت‌کننده‌ی ضربدری به‌کار رود کاهش پاسخ ارتعاشی نسبت به حالت بدون به‌کارگیری سفت‌کننده پدید می‌آید. ولی به‌کارگیری سفت‌کننده می‌تواند در پاسخ صوتی سامانه تأثیر چشم‌گیری بگذارد، به گونه‌ای که به‌کارگیری سفت‌کننده‎ی قطری، پاسخ صوتی سامانه را به اندازه‎ی زیادی کاهش داده است. هم‌چنین، به‌کارگیری سفت‌کننده ضربدری می‌تواند کاهش خوبی در پاسخ صوتی پدید آورد. کاربرد سفت‌کننده با اعضای موازی نسبت به حالتی که سفت‌کننده به‌کار نرفته باشد اثر چشم‎گیری روی پاسخ صوتی و ارتعاشی سامانه ندارد. نمودارهای افت تراگسیل صدا در گستره‎ی بسامد نشان می‌دهند که سفت‌کننده‎ی ضربدری بهترین کارایی را داشته و به دنبال آن سفت‌کننده‎ی قطری، حالت بدون سفت‌کننده و سفت‌کننده‎ی موازی جای دارند. 2 The need to understand how to implement the structural quieting into the design processes has led the engineers to pay more attention to noise generation and transmission from the vibrating structures. In this study, utilizing the finite element software ABAQUS, the acoustical and vibrational response of stiffened steel plate opening wall in a RC room subject to blast has been investigated. Moreover, frequency analysis has been performed on each of the stiffener arrangements, in order to obtain the transmission loss of the generated noise in frequency domain under the effect of a diffused field of a white noise. The three stiffener arrangements of diagonal, cross, and parallel have been used in the analysis. The results indicate that the stiffener arrangements has marginal effect on the vibrational response of the system, whereas its influence on the acoustical response of the system is substantially high. For instance, the cross and diagonal stiffeners showed, in a descending order, the best performance in the noise transmission loss of the system. 1 9 2015/02/16 1393/11/27 2015/06/29 1394/4/8 سعیدرضا مساح S.R. Massah گروه سازه و زلزله، دانشکده مهندسی عمران ایران massah@iust.ac.ir حمید زهره‌وند H. Zohrevand گروه سازه و زلزله، دانشکده مهندسی عمران ایران عباس قدمی A. Ghadami گروه سازه و زلزله، دانشکده مهندسی عمران ایران Acoustical response Vibrational response Transmission loss Stiffened. پاسخ صوتی پاسخ ارتعاشی افت تراگسیل سفت‌کننده. [1] G. Maidanik, “Response of ribbed panels to reverberant acoustic fields,” The Journal of the Acoustical Society of America, vol. 34, no. 6, pp. 809-826, 1962.##[2] F. Fahy, “Sound and Structural Vibration: Radiation, Transmission and Response,” Academic Press, London, 1985.##[3] J.H. Lee, J. Kim, “Analysis of sound transmission through periodically stiffened panels by space-harmonic expansion method,” Journal of Sound and Vibration, vol. 251, no.2, pp. 349-366, 2002.##[4] D.J. Mead, “Space-harmonic analysis of periodically supported beams: response to convected random loading,” Journal of Sound and Vibration, vol. 14, no.4, pp. 525-531, 1971.##[5] D.J. Mead, “Free wave propagation in periodically supported infinite beams,” Journal of Sound and Vibration, vol. 11, no.2, pp. 181-197, 1970.##[6] D.J. Mead, “Wave propagation in continuous periodic structures: research contributions from Southampton, 1964–1995,” Journal of Sound and Vibration, vol. 190, no.3, pp. 495-524, 1996.##[7] C. Maury, P.O. Mattei, “Sound transmission through a rib-stiffened plate: comparisons of a light fluid approximation with experimental results,” Journal of Sound and Vibration, vol. 249, no. 1, pp. 206-212, 2002.##[8] T.R. Lin, J. Pan, “A closed form solution for the dynamic response of finite ribbed plates,” The Journal of the Acoustical Society of America, vol. 119, pp. 917-925, 2006.##[9] T.R. Lin, “A study of modal characteristics and the control mechanism of finite periodic and irregular ribbed plates,” The Journal of the Acoustical Society of America, vol. 123, pp. 729-737, 2008.##[10] B. Liu, L. Feng, A. Nilsson, “Sound transmission through curved aircraft panels with stringer and ring frame attachments,” Journal of Sound and Vibration, vol. 300, no. 3-5, pp. 949-973, 2007.##[11] E.E. Ungar, “Transmission of plate flexural waves through reinforcing beams; dynamic stress concentrations,” The Journal of the Acoustical Society of America, vol. 33, pp. 633-639, 1961.##[12] B. Mace, “The response of a fluid-loaded, beam-stiffened plate,” Journal of Sound and Vibration, vol. 79, pp. 439-542, 1981.##[13] E. Popov, “Mechanics of Materials,” Prentice-Hall, Englewood Cliffs, New Jersey, 1976.##[14] L. Louca, Y. Pan, J. Harding, “Response of stiffened and unstiffened plates subjected to blast loading,” Engineering Structures, vol. 20, pp. 1079-1086, 1998.## ##

تعیین ژل دُزسنجی بهینه از ترکیب ژل‌های مجیک- اف و مقلِّد بافت با استفاده از پارامترهای فراآوایی در انرژی مگاولتاژ Determination optimal gel dosimetry of the MAGIC-f and Tissue Mimicking composition using ultrasonic parameters in megavoltage energy 1 1 با استفاده از ترکیب ساختار ژل بس‌پاری (پلیمری) مجیک- اف و فانتوم مقلِّد بافت (تیشو میمیکینگ)، در این مطالعه مقصود دست یافتن به ساختار بهینهای از ژل‌های دُزسنجی با هدف افزایش حساسیت ژل و کاهش هزینه ساخت می‌باشد. پنج نمونه از ژل‌های ساختار جدید، که از ترکیب ساختار ژل بس‌پاری مجیک- اف و فانتوم مقلِّد بافت (نسج) تهیه شده بودند، در معرض تابش پرتو مگاولتاژ کبالت قرار داده شدند. سپس، پارامترهای فراآوایی سرعت صدا، ضریب تُنُکِش (تضعیف) و شاخص کیفی نمونه ژل‌ها در زمان 24 ساعت پس از تابش و در دمای 25 درجه سلسیوس در دُزهای 0 و 36 گری مورد بررسی قرار گرفتند، تغییرات حساسیت نمودار دُز- پاسخ برای پارامترهای فراآوایی 5 نمونه ژل بس‌پاری (پلیمری) جدید مورد بررسی قرار گرفتند. نتایج اندازه‌گیری نشان دادند که با خوانش پارامتر سرعت صدای 5 نمونه از ترکیبات ساختار ژل بس‌پاری (پلیمری) در زمان 24 ساعت پس از تابش و دمای 25 درجه سلسیوس، برای ساختار ژل «دی» (6/34 m/s) بیش‌ترین تغییرات را داشته، که برای ساختار «اِیی» برابر 8/31 m/s و برای ساختار «دی» این تغییرات برابر 20 m/s بدست آمد، برای ساختار «سی» تقریبا 1 m/s و برای ساختار «اِی» تقریبا صفر حاصل شد. نتایج نمودار تغییرات برای پارامتر ضریب تُنُکِش (تضعیف) برای ساختار «دی» برابر 7/0 db/MHz و برای ساختار «اِیی» و «بی» به ترتیب 5/0 و 4/0 db/MHzمی‌باشند. برای ساختارهای «اِی» و «سی» نیز این مقادیر تقریبا 2/0 db/MHz تعیین شدند. مقادیر تغییرات تعیین‌شده برای نمودار شاخص کیفی برای ساختار «دی» برابر 10 و برای «اِیی» برابر 6/7 هستند و برای ساختارهای «اِی»، «بی» و «سی» به ترتیب برابر 4/0، 7/4 و صفر می‌باشند. بهترین ساختار در این بررسی ژل «دی» بوده که بیشترین تغییرات پارامترهای صوتی را داشته است. هم‌چنین، با بررسی ساختارهای 5 نمونه ژل، با افزایش مقدار ژلاتین در ساختار ژل‌ها حساسیت افزایش می‌یابد. بعلاوه، در ساختارهایی که از ترکیبات اسید اسکوربیک، سولفات مس و متااکریلیک اسید استفاده نشده، پارامترهای صوتی به افزایش دُز تغییرات محسوسی نشان ندادند. 2 In this study, we used 5 types of combination of MAGIC-f polymer gel and tissue mimicking phantom to extract the optimal structure of gel dosimetry to increase sensitivity and reduce gel manufacturing costs. 5 types of new structure gels were irradiated by a dose of 36 Gy using a gamma ray (cobalt-60) source. Irradiated gels again, were refrigerated at 5 ºC for about 24 hours before reading. The parameters: ultrasonic speed of sound, attenuation coefficient and quality index of 5 types of new structure gels were measured at 24 hours after exposure and at 25 ºC with Sonost 2000 ultrasound system, variation of sensitivity of dose-response curve for ultrasound parameters of 5 new structure polymer gels were evaluated. The measurement results showed the D type of the new gel structures had the greatest change (34.6 m/s) in the speed of sound parameter. The change in A, B, C and E structures was measured to be 0, 20, 1 and 31.5 m/s respectively. Also, the obtained attenuation coefficient parameters for A, B, C, D and E structures were 0.2, 0.4, 0.2, 0.7 and 0.5 db/MHz respectively. Quality index parameter extracted for A, B, C, D and E structures, 0.4, 4.7, 0, 10 and 7.6 respectively. The D type structure had the greatest sensitivity among the 5 types of the new structure of the gels in this study. Also increasing the amount of gelatin in gel structure, increases the sensitivity. The ultrasound parameters had no significant changes for structures not containing ascorbic acid, copper sulfate and metacrylic acid. 10 18 2015/02/162015/08/19 1394/5/28 2015/06/292016/01/10 1394/10/20 سیدحسین معصومی S.H. Masoumi گروه فیزیک پزشکی، دانشکده علوم پزشکی ایران saroo25@yahoo.com منیژه مختاری دیزجی M. Mokhtari Dizaji گروه فیزیک پزشکی، دانشکده علوم پزشکی ایران mokhtarm@modares.ac.ir اعضیم اربابی A. Arbabi گروه فیزیک پزشکی، دانشکده علوم پزشکی ایران محسن بخشنده M. Bakhshandeh گروه فیزیک پزشکی، دانشکده علوم پزشکی ایران MAGIC-f polymer gel Tissue Mimicking Speed of sound Attenuation coefficient Quality index. ژل بس‌پاری (پلیمری) مجیک- اف مقلِّد بافت سرعت صدا ضریب تُنُکِش (تضعیف) شاخص کیفی. [1] T.C .Chainq, H. Culbert, B. Wyman, L. Cohen, J. Ovadia,“The half field technique of radiation therapy for the cancers of head and neck,” International Journal of Radiation Oncology and Biology Physics, vol. 5, no. 10, pp. 123-126, 1979.##[2] R. Datta, J.G. Mira, T.C. Pomeroy, S. Datta, “Dosimetry study of split beam technique using megavoltage beam and its clinical implications,” International Journal of Radiation Oncology and Biology Physics, 5, pp. 256-270, 1979.##[3] F.M. Khan, “The Physics of Radiation Therapy,” Third edition, William and Wilkins, 2003.##[4] J.C. Gore, Y.S. Kang, R.J. Schulz, “Measurement of radiation dose distributions by nuclear magnetic resonance (NMR) imaging,” Physics in Medicine and Biology, vol. 29, no. 10, pp. 1189-1197, 1984.##[5] M.J. Maryanski, R.J. Schulz, G.S. Ibbott, J.C. Gatenby, J. Xie, D. Horton, J.C. Gore, “Magnetic resonance imaging of radiation dose distributions using a polymer-gel dosimeter,” Physics in Medicine and Biology, vol. 39, no. 9, pp. 1437-1455, 1994.##[6] M.J. Maryanski, R.J. Schulz, G.S. Gore, “Three dimensional dose distributions for 160 MeV protons using MRI of the tissue-equivalent BANG polymergel dosimeter,” PTCOG Newsletter, pp. 10-11, 1994.##[7] M.J. Maryanski, J.C. Gore, R.P. Kennan, R.J. Schulz, “NMR relaxation enhancement in gels polymerized and cross-linked by ionizing radiation: A new approach to 3D dosimetry by MRI,” Magnetic Resonance Imaging, vol. 11, no. 2, pp. 253-258, 1993.##[8] Y. De Deene, C. De Wagter, B. Van Duyes, S. Derycke, B. Mersseman, W. De Gersem, T. Voet, E. Achten, W. De Neve, “Validations of MR-based polymer gel dosimetry as a preclinical three-dimentional verification tool in conformal radiotherapy,” Magnetic Resonance Imaging, vol. 43, no. 1, pp. 116-125, 2000.##[9] P. Haraldsson, S.Å.J. Bäck, P. Magnusson, L.E. Olsson, “Dose response characteristics and basic dose distribution data for a polymerization-based dosimeter gel evaluated using MR,” British Journal of Radiology, vol. 73, pp. 58-65, 2000.##[10] Y. De Deene, C. Hurley, A. Venning, K. Vergote, M. Mather, B.J. Healy, C. Baldock, “A basic study of some normoxic polymer gel dosimeters,” Physics in Medicine and Biology, vol. 47, no. 19, pp. 3441-3463, 2002.##[11] C. Baldock, R.P. Burford, N. Billingham, G.S. Wagner, S. Patval, R.D. Badawi, S.F. Keevil, “Experimental procedure for the manufacture and calibration of polyacrylamide gel (PAG) for magnetic resonance imaging MRI radiation dosimetry,” Physics in Medicine and Biology, vol. 43, no. 3, pp. 695-702, 1998.##[12] C. Baldock, L. Rintoul, S.F. Keevil, J.M. Pope, G.A. George, “Fourier transform raman spectroscopy of polyacrylamide gel (PAGs) for radiation dosimetry,” Physics in Medicine and Biology, vol. 43, no. 12, pp. 3617-3627, 1998.##[13] M. Sittig, “Handbook of Toxic and Hazardous Chemicals and Carcinogens,” second edition, Noyes Publications, New Jersey, USA, pp. 41-44, 1985##[14] M. Mc Jury, M. Oldham, V.P. Cosgrove, P.S. Murphy, S. Doran, M.O. Leach, S. Webb “Radiation dosimetry using polymer gels: Methods and applications,” British Journal of Radiology, vol. 73, no. 873, pp. 919-929, 2000.##[15] P.M. Fong, D.C. Keil, M.D. Does, J.C. Gore “Polymer gels for magnetic resonance imaging of radiation dose distributions at normal room atmosphere,” Physics in Medicine and Biology, vol. 46, no. 12, pp. 3105-3113, 2001.##[16] Y. De Deene, K. Vergote, C. Claeys, C. De Wagter, “The fundamental radiation properties of normoxic polymer gel dosimeters: A comparison between a methacrylic acid based gel and acrylamide based gels,” Physics in Medicine and Biology, vol. 51, no. 3, pp. 653-673, 2006.##[17] C. Hurley, A. Venning, C. Baldock, “A study of normoxic polymer gel dosimeter comprising methacrylic acid, gelatin and tetrakis (hydroxymethyl) phosphonium chloride (MAGAT),” Applied Radiation and Isotopes, vol. 63, no. 4, pp. 443-456, 2005.##[18] J.J. Luci, H.M. Whitny, J.C. 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Cechak “Energy and dose rate dependence of BANG-2 polymer-gel dosimeter,” Journal of Medical Physics, vol. 28, no. 11, pp. 2379-2386, 2001.##[31] Y. De Deene, A. Venning, C. Hurley, B.J. Healy, C. Baldock, “Dose-response stability and integrity of the dose distribution of varios polymer gel dosimeters,” Physics in Medicine and Biology, vol. 47, no. 14, pp. 2459-2470, 2002.##[32] Y. De Deene, K. Vergote, C. Claeys, C. De Wagter, “The fundamental radiation properties of normoxic polymer gel dosimeters: A comparision between a methacrylic acid based gel and acrylamide based gels,” Physics in Medicine and Biology, vol. 51, no. 3, pp. 653-673, 2006.##[33] A. Karlsson, H.S. Gustavsson, S. Månsson, K.B. McAuley, S.A. Bäck, “Dose integration characteristics in normoxic polymer gel dosimetry investigated using sequential beam irradiation,” Physics in Medicine and Biology, vol. 52, no. 15, pp. 4697-4706, 2007.##[34] R.A. Crescenti, J.C. Bamber, N.L. Bush, S. Webb, “Characterization of dose-dependent Young’s modulus for a radiation-sensitive polymer gel,” Physics in Medicine and Biology, vol. 54, no. 4, pp. 843-857, 2009.##[35] M.L. Mather, A.K. Whittaker, C. Baldock, “Ultrasound evaluation of polymer gel dosimeters,” Physics in Medicine and Biology, vol. 47, no. 9, pp. 1449-1458, 2002.##[36] T.J. Atkins, V.F. Humphrey, F.A. Duck, M.A. Tooley, “Investigation of ultrasonic properties of MAGIC gels for pulse-echo gel dosimetry,” Journal of Physics: Conference Series, vol. 250, no. 1, pp. 1-5, 2010. ##[37] M.J. Maryañski, Y.Z. Zastavker, J.C. Gore, “Radiation dose distributions in three dimensions from tomographic optical density scanning of polymer gels: II. Optical properties of the BANG polymer gel,” Physics in Medicine and Biology, vol. 41, no. 12, pp. 2705-2717, 1996.## ##

اثر مواجهه با نوفه 85 دسی‌بل و بالاتر بر شاخص کرنش کارگران ماشین‌کار زن (25 الی 30 ساله) در تولیدی‌های قطعات وسایل گازسوز Noise effect on strain index of machinery women age (25-30 year) in gas supplies parts manufacturers 1 1 شاخص کرنش (استرین) برای سنجش تنش (استرس) پوسچرال در اندام‌های فوقانی بکار می‌رود و به علت سرعت بالای کار، پوسچر نامناسب بدنی، اعمال نیروی زیاد، استراحت‌های ناکافی و کار تکراری بوجود می‌آید و از علل شکایات کارگران در بخش ماشین‌کاری صنایع سازنده قطعات گازسوز است که در برخی ایستگاه‌های کاری دارای صدای بالاتر از 85 دسی‌بل هستند. اطلاع از اثر صدا بر شاخص کرنش (استرین) این کارگران، موضوع این تحقیق است. حجم نمونه 50 نفر شامل دو گروه در معرض صدای بالا و در معرض صدای کم است. بخش اداری نیز به عنوان شاهد بررسی شد. جمع‌آوری اطلاعات با پرسش‌نامه نوردیک صورت گرفت. ارزیابی پوسچر با مشاهده هر وظیفه و تکمیل سیاهه بررسی (چک لیست) شاخص کرنش (استرین) انجام شد. متغیر شدت تلاش با اندازه‌گیری ضربان قلب فرد در حین فعالیت با دستگاه آزمون ورزش سنجیده شد و شاخص بورگ محاسبه و در عدد شاخص کرنش (استرین) بکار رفت. سنجش صدا با استفاده از صداسنج و دُزسنج به تناسب نوع صدا (یکنواخت و متغیر) صورت گرفت. تحلیل نتایج با استفاده از آزمون‌های من- ویتنی، کروسکال- والیس، تحلیل واریانس یک طرفه، ضریب همبستگی اسپیرمن انجام شد. بین سابقه کار و درد گردن، درد شانه، درد مچ، ارتباط معنادار بدست آمد. یافته‌ها نشان دادند که بین شاخص کرنش (استرین) دو گروه در مواجهه با صدا تفاوت وجود دارد، اما معنادار نیست. افزایش نوفه به بالای 85 دسی‌بل باعث افزایش شاخص کرنش (استرین) می‌گردد، ولی این نتیجه از نظر آماری معنادار نیست. 2 Postural stress is one of the major complaints of women machinery works at gas supply parts manufacturers which have noise levels equal or above 85 dB in some of their workstations. Postural stress is caused by workplace ergonomic risk factors: High work-speed, repetitive work, poor body posture, excessive force and inadequate break time. Knowledge of the effect of the noise on the strain index is the subject of this investigation. The sample size was decided to be 50 persons, two groups were selected as targets. One group exposed to high level of noise, and the other group subjected to low noise level. The administrative employees were treated as control group. Nordic questionnaire was used to collect informations. Posture was assessed by observing each task and SI checklist was filled out of effort variable was measured by person’s heat rate during her work and sport tester machine was used to this aim. Borg scale and then SI were calculated. Noise was measured by sound level meter and noise dosimeter in accordance with noise type. Data Analyzing was performed by man-whitney, Kruskal-Wallis, one-way ANOVA and spearman correlation in SPSS (ver.16) software. The results showed statistically significant relation between work experience and neck pain, shoulders pain and wrist/ hand pain. They also revealed that there is difference between strain indices two groups but it is not statistically significant. Strain index can be increased by noise levels above 85 dB but this is not of statistical consequence. 19 26 2015/02/162015/08/192014/11/25 1393/9/4 2015/06/292016/01/102015/11/11 1394/8/20 نسرین ذوالفقاری‌نژاد N. Zolfaghari Nejhad گروه مهندسی بهداشت حرفه‌ای، دانشکده علوم پزشکی ایران nasrin.zolfaghari@modares.ac.oo.com علی خوانین A. Khavanin گروه مهندسی بهداشت حرفه‌ای، دانشکده علوم پزشکی، ایران Khavanin@modares.ac.ir شهرام وثوفی S. Vosoughi گروه علوم بهداشت، دانشکده سلامت ایمنی و محیط‌زیست ایران SH_vosoughi@yahoo.com Postural stress Strain index Noise above 85 dB Industrial noise Nordic questionnaire. تنش پوسچرال شاخص کرنش نوفه بالای 85 دسی‌بل نوفه محیط کار پرسش‌نامه نوردیک. [1] W.N. Rom, “Environmental and Occupational Medicine,” Third edition Philadelphia, Lippincott Raven Press, 1988.##[2] W. Melnick, “Hearing Loss from Noise Exposure, Handbook of Noise Control,” Harris CM, McGrow Hill, New York, Chapter 15, pp. 1, 1979.##[3] P.W. Alberti “Noise, the most ubiquitous pollutant,” Noise Health, vol. 1, no. 1, pp. 3-5,1998.##[4] “Noise exposure regulation,” Turkey Organization Standards, Ministry of Environment, Republic of Turkey, 1986.##[5] S. Melamed, Y. Fried, P. Froom, “The interactive effect of chronic exposure to noise and job complexity on changes in blood pressure and job satisfaction: A longitudinal study of industrial employees,” Journal of Occupational Health Psychology, vol. 6, no. 3, pp. 182, 2001.##[6] M.A. De Jung, K.R. Van Mourik, H.M.C. Schellekens, “A physiological approach to aesthetic preference-music,” Psychotherap Psychosomat, vol. 22, pp. 46-51, 1973.##[7] S.A. Stansfeld, M.P. Matheson, “Noise pollution: Non-auditory effects on health,” British Medical Bulletin, vol. 68, pp. 243-257, 2003.##[8] B. Dalton, D. Behm, “Effects of noise and music on human and task performance: A systematic review,” Occupational Ergonomics, vol. 7, no. 3, pp. 165-183, 2007.##[9] S.L. Lusk, B. Gillespie, B.M. Hagerty, R.A. Ziemba, “Acute effects of noise on blood pressure and heart rate,” Arch Environ Health, vol. 59, no. 8, pp. 392-399, 2004.##[10] W. Babisch, “Cardiovascular effects of noise,” Noise Health, vol. 13, no. 52, pp. 201-204, 2011.##[11] M. Laad, “The study of the effect of sounds of constant frequency and varying intensity levels on systolic blood pressure, diastolic blood pressure and heart rate of healthy individuals,” Annals of Faculty Engineering Hunedora. International Journal of Engineering, pp. 107-109, 2011.##[12] M. Alikhani, H. Akbari, H. Alamdari, “Correlation between sound pressure level and blood pressure workers Fajrsepahan Galvanizing Kashan,” National Conference on Health Profession‌als Iran, Hamedan, pp. 431-435, 2004.##[13] Z. Zamanian, R. Rostami, J. Hasanzadeh, H. Hashemi, “Effects of exposure to workplace noise on blood pressure and heart rate workers in an iron and steel industry,” Journal of Environmental and Public Health, 2013.##[14] V. Putz-Anderson, “Cumulative Trauma Disorders: A Manual for Musculoskeletal Disorders of the Upper Limbs,” Taylor and Francis, pp. 75-89, 1994.##[15] M. Aptel, A. Aublet-Cuvelier, J.C. Cnockaert, “Work related musculoskeletal disorders of the upper limb,” Joint Bone Spine, vol. 69, no. 6, pp. 546-555, 2002.##[16] B.A. Larson, M.T. Ellexson, “Blueprint for ergonomics,” Work, vol. 15, no. 2, pp. 107-112, 2000.##[17] D. Denis, S. Vincent, “Intervention practices in musculoskeletal disorder prevention: A critical literature review,” Applied Ergonomics, vol. 39, no. 1, pp. 1-14, 2008.##[18] J.S. Moore, A. Garg, “The strain index: A proposed method to analyze jobs for risk of distal upper extremity disorders,” AIHAJ American Industrial Hygiene Association Journal, vol. 56, no. 5, pp. 443-458, 1995.##[19] G. Li, P. Buckle, “Current techniques for assessing physical exposure to work related musculoskeletal risks with emphasis on posture-based methods,” Ergonomics, vol. 42, no. 5, pp. 674-695, 1999.##[20] A.M. Genaidy, A.A. Alshedi, W. Karwowski, “Postural stress analysis in industry,” Applied Ergonomics, vol. 25, no. 2, pp. 77-87, 1994.##[21] P. Spielholz “Calibrating borg scale ratings of hand force exertion,” Applied Ergonomics, vol. 37, no. 5, pp. 615-618, 2005.##[22] S. Bao, P. Spielholz, N. Howard, B. Silverstein, “Application of the strain index in multiple task jobs,” Applied Ergonomics, vol. 40, no. 1, pp. 56-68, 2009.##[23] T.R. Waters, V. Putz-Anderson, A. Garg, “Applications manual for the revised NIOSH lifting Equation,” United States department of Health and Human Services, Chapter 1, pp. 4-34, Publication no. 94-110, Cincinnati, Ohio, USA, 1994.##[24] C.E. Dickinson, K. Campion, A.F. Foster, S.J. Newman, A.M. O’Rourke, P.G. Thomas, “Questionnaire development: An examination of the nordic musculoskeletal questionnaire,” Applied Ergonomics, vol. 23, no. 3, pp. 197-201, 1992.##[25] M. Pourmahabadian, J.N. Saraji, M. Aghabeigi, H. Saddeghi-Naeeni, “Risk assessment of developing distal upper extremity disorders by strain index method in an assembling electronic industry,” Acta Medica Iranica, vol. 43, no. 5, pp. 347-354, 2005.##[26] Z. Rowshani, S.B. Mortazavi, A. Khavanin, R. Mirzaei, M. Mohseni, “Comparing RULA and strain index methods for the assessment of the potential causes of musculoskeletal disorders in the upper extremity in an electronic company in Tehran,” Feyz Journal of Kashan University of Medical Sciences, vol. 17, no. 1, pp. 61-70, 2013.##[27] M. Motamedzade, M. Mohseni, R. Golmohammadi, H. Mahjoob, “Ergonomics intervention in an Iranian television manufacturing industry,” Work, vol. 38, no. 3, pp. 257-263, 2011.##[28] M. Mohammadian Mastanabad, M. Motamedzade, J. Faradmal, “Investigating the correlations of OCRA index, strain index and ACGIH HAL methods for assessing the risk of upper limb musculoskeletal disorders,” Journal of Ergonomics, vol. 1, no. 2, pp. 63-71, 2013.##[29] A.P. Dawson, E.J. Steele, P.W. Hodges, S. Stewart, “Developement and test-retest reliability of an extended version of the Nordic Musculoskeletal Quesrionnaire (NMQ-E): A screening instrument for musculoskeletal pain,” The Journal of Pain, vol. 10, no. 5, pp. 517-526, 2009.##[30] S. Knardahl, “The General Nordic questionnaire for psychological and social factors at work,” Scandinavian Journal of Organizational Psychology, pp. 26-27, 2000.## ##

بررسی دو بعدی تأثیرات سه جنس و هندسه منظم بستر دریا بر انتشار صدا با بسامد پایین در محیط دریایی Two-dimensional investigation of the effects of three materials and regular geometry of seabed on low frequency sound propagation in marine environment 1 1 انتشار صدا با بسآمد پایین در زیر آب یکی از مهم‌ترین موضوعات تحقیقاتی در سال‌های اخیر است. از جمله دلایل اهمیت این موضوع می‌توان به قرارگیری نوفه شناورهای سطحی و زیرسطحی در این گروه از امواج صدا اشاره نمود. برای شناخت رفتار صدا در زیر آب می‌بایست عوامل مؤثر بر آن را بررسی نمود. در مقاله حاضر، به تحلیل عددی تأثیرات هندسه منظم و سه جنس‌ مختلف بستر دریا بر انتشار صدا پرداخته شده است. برای این منظور، معادله سهموی انتشار موج صدا با استفاده از روش تفارق متناهی ضمنی حل شده است. نتایج نشان دادند که افت تراگسیل صدا برای بستر سنگ خارا با هندسه مثلثی و نیم‌دایره‌ای، با افزایش مسافت، پلکانی کاهش می‌یابد. اما برای هندسه مستطیلی، افزایش تدریجی خواهد داشت. مقادیر افت تراگسیل برای بستر ماسه‌سنگ نیز در سه هندسه یاد شده، با افزایش برد، افزایش پیدا می‌کنند. اما در این حالت میانگین افت تراگسیل هندسه نیم‌دایره‌ای، حدود 4 دسی‌بل کم‌تر است. از طرف دیگر، بستر صلب، ماسه‌سنگ و سنگ خارا برای هندسه مستطیلی تأثیر چشم‌گیری بر افت تراگسیل صدا در عمق 30 متری آب ندارند. 2 Low frequency underwater sound propagation is one of the most important topics of research in recent years. This can be attributed to the noise generated by underwater and surface vessels. To better understand the behavior of the underwater sound, different factors affecting sound must be investigated. In the current study, numerical analysis of the effects of regular geometry and three materials of seabed on sound propagation is conducted. To this end, parabolic equation governing the sound wave propagation is solved using implicit finite difference scheme. The obtained results indicate that transmission loss (TL) of the granite bottom with triangular and semicircular geometries is reduced by an increase in distance. However, TL gradually increases in the case of rectangular geometry. Values of transmission loss of the sandstone bottom are increased by an increase in the range for the mentioned geometries. However, average value of TL for the semicircular geometry is about 4 decibels less than the other two geometries. On the other hand, rigid, sandstone, and granite seabed have no significant influence on the graph of TL for the rectangular geometry at 30m depth. 27 36 2015/02/162015/08/192014/11/252015/07/27 1394/5/5 2015/06/292016/01/102015/11/112016/01/25 1394/11/5 سامان کرمانی S. Kermani دانشکدۀ مهندسی دریا ایران samankermani@aut.ac.ir پرویز قدیمی P. GHadimi دانشکدۀ مهندسی دریا ایران pghadimi@aut.ac.ir Underwater sound propagation Low frequency Geometry of bottom Material of bottom Parabolic equation. انتشار صدا زیر آب بسآمد پایین هندسه بستر جنس بستر معادله سهموی. [1] H. Medwin, R. Spaulding, “Shadowing by seamounts,” Journal of Acoustical Society of America, vol. 66, pp. S76, 1979.##[2] K.M. Guthrie, R.N. Denham, R.W. Bannister, D.G. Browning, “The effect of seamounts on SOFAR propagation: Louisville Ridge II,” Journal of Acoustical Society of America, vol. 68, pp. S52, 1980.##[3] G.R. Ebbeson, R.G. Turner, “Acoustic reflections from a seamount in the northeast Pacific,” Journal of Acoustical Society of America, vol. 68, pp. S78, 1980.##[4] G.B. Morris, W.B. Fincke, “Acoustic shadowing and reflections from Stoddard Seamount, Northeast Pacific,” Journal of Acoustical Society of America, vol. 69, pp. S59, 1981.##[5] P.D. Koenigs, R.F. LaPlante, D.G. Browning, R.L. Martin, “Long‐range sound propagation across Atlantic Ocean seamounts: Implications for ambient noise,” Journal of Acoustical Society of America, vol. 69, pp. S59, 1981.##[6] J.J. Sikora, “Sound propagation around underwater seamounts,” M.Sc. Thesis, Department of Electrical Engineering and Computer Science, Massachusetts, Massachusetts Institute of Technology, USA, 2005.##[7] C.H. Harrison, “Three‐dimensional ray paths in basins, troughs, and near seamounts by use of ray invariants,” Journal of Acoustical Society of America, vol. 62, pp. 1382, 1977.##[8] F.B. Jensen, W.A. Kuperman, H. Medwin, “Propagation over a seamount,” Journal of Acoustical Society of America, vol. 68, pp. S52, 1980.##[9] M.J. Buckingham, “Theory of acoustic propagation around a conical seamount,” Journal of Acoustical Society of America, vol. 80, pp. 265, 1986.##[10] I. Tolstoy, “Exact, explicit solutions for diffraction by hard sound barriers and seamounts,” Journal of Acoustical Society of America, vol. 85, pp. 661, 1989.##[11] D.R. Burns, “Acoustic and elastic scattering from seamounts in three dimensions-A numerical modeling study,” Journal of Acoustical Society of America, vol. 92, pp. 2784, 1992.##[12] C.R. Bradley, R.A. Stephen, “Modeling of seafloor wave propagation and acoustic scattering in 3‐D heterogeneous media,” Journal of Acoustical Society of America, vol. 100, pp. 225, 1996.##[13] D.R. Jackson, A.N. Ivakin, “Scattering from elastic sea beds: First-order theory,” Journal of Acoustical Society of America, vol. 103, pp. 336-345, 1998.##[14] J.A. Fawcett, “Modeling scattering from azimuthally symmetric bathymetric features using wavefield superposition,” Journal of Acoustical Society of America, vol. 122, pp. 3286-3295, 2007.##[15] H. Schmidt, W. Luo, “Coupled mode modeling of 3-D propagation and scattering around conical seamount,” AIP Conference Proceedings, vol. 1272, no. 1, 2010.##[16] R. Pannatoni, “Scattering of sound by a cylindrically symmetric seamount,” Journal of Acoustical Society of America, vol. 135, 2014.##[17] E.G.A. Costa, L. Godinho, A. Pereira, J.A.F. Santiago, “Prediction of acoustic wave propagation in a shallow water configuration using the method of fundamental solutions,” Journal of Computational Acoustics, vol. 20, 2012.##[18] T.F. Argo, “Laboratory measurements of sound speed and attenuation of water-saturated granular sediments,” PhD Thesis, The University of Texas, Austin, 2012.##[19] S.D. Frank, R.I. Odom, J.M. Collis, “Elastic parabolic equation solutions for underwater acoustic problems using seismic sources,” Journal of Acoustical Society of America, vol. 133, no. 3, pp. 1358-1367, 2013.##[20] A.J. Duncan, A.N. Gavrilov, R.D. McCauley, I.M. Parnum, J.M. Collis, “Characteristics of sound propagation in shallow water over an elastic seabed with a thin cap-rock layer,” Journal of Acoustical Society of America, vol. 134, no. 1, pp. 207-215, 2013.##[21] M.S. Ballard, B.M. Goldsberry, M.J. Isakson, “Normal mode analysis of three-dimensional propagation over a small-slope cosine shaped hill,” Journal of Computational Acoustics, vol. 23, no.3, 2015.##[22] P.C. Etter, “Underwater Acoustic Modeling and Simulation,” Third edition, New York, Taylor & Francis, 2003. ##[23] F.B. Jensen, C.M. Ferla, “Numerical solutions of range-dependent benchmark problems in ocean acoustics,” Journal of Acoustical Society of America, vol. 87, pp. 1499, 1990.## ##

بررسی تأثیر امواج فراصدا بر واکنش آوکافت نشاسته توسط آنزیم آلفا-آمیلاز The effect of ultrasound on the enzymatic hydrolysis of starch with alpha-amylase enzyme 1 1 در این پروژه، اثر امواج فراصدا بر فعالیت و پارامترهای جنبشی (سنیتیکی) ﺁوکافت (هیدرولیز) آنزیمی نشاسته توسط آلفا آمیلاز مورد بررسی قرار گرفت. برای این منظور، آنزیم آلفا آمیلاز برای بازه‌های زمانی متفاوت و بسامد ثابت 20 کیلوهرتز در معرض امواج فراصدا قرار گرفت، سپس فعالیت آن سنجیده شد. نتایج نشان دادند که حداکثر فعالیت نسبی آنزیم در عدم حضور امواج بوده و افزایش زمان امواج‌دهی باعث کاهش فعالیت آنزیم می‌شود. فعالیت نسبی آنزیم در زمان‌های 0، 10، 20 و 30 دقیقه به ترتیب برابر با 100، 13/92، 62/34 و 47/7 درصد است. پی‌اچ و دمای بهینه برای فعالیت آنزیم در حضور و غیاب امواج مشابه بودند (درجه سلسیوس 50T= در 6pH=). مقدار Km تغییر قابل توجهی نداشت، در حالی‌که نتایج، یک کاهش در مقدار Vmax را نشان می‌دهند. هنگامی که محلول حاوی آنزیم و نشاسته هم‌زمان در معرض امواج قرار گرفتند، در مدت زمان 10 دقیقه تابش، درصد تبدیل نشاسته بیش‌تر از شرایط بدون تابش است در حالی‌که در مدت زمان 20 و 30 دقیقه تابش، این درصد کم‌تر از شرایط معمولی است. به علاوه، اثر این امواج بر روی ساختار آمیلاز توسط روش‌های طیف‌سنجی فلورسانس و لزجت‌سنجی (ویسکومتری) مورد مطالعه قرار گرفت. با استفاده از این نتایج می‌توان اثر دوگانه‌ای از امواج را بر عملکرد آنزیم آمیلاز نتیجه گرفت؛ یک اثر تخریبی بر روی ساختار آمیلاز و یک اثر سازنده بر روی افزایش بسآمد برخورد سوبسترا و آنزیم و در نتیجه افزایش ﺁوکافت (هیدرولیز) آنزیمی مشاهده می‌شود. 2 In this research, the effect of ultrasound (US) on the activity and the kinetic parameters of enzymatic hydrolysis of starch by alpha-amylase were investigated. To this aim, alpha-amylase was exposed to ultrasonic irradiation for different time intervals and a constant frequency of 20 kHz, then its enzymatic activity was measured. According to the results, the maximum activity of amylase was recorded in the absence of US and increasing the irradiation time reduced the enzymatic activity. The relative activity of amylase under irradiation time intervals of 0, 10, 20 and 30 min were 100, 92.13, 34.62 and 7.47 percent, respectively. The optimum pH and temperature for amylase activity in both, the absence and presence of US were similar (T=50º C and pH=6). There was no considerable change in Km, while the results showed a decrease in the value of Vmax. In comparison with the corresponding value in the absence of US, the enzymatic hydrolysis increased when the enzyme and starch solutions were exposed to the US for 10 minutes. However, this value decreased when the solutions were exposed to US for 20 and 30 minutes. Furthermore, the effect of ultrasound on the structure of amylase were studied using viscometeric and florescence spectroscopy. These results indicated that, US have equivocal effect on enzyme activity. One effect was a destructive one on the structure of amylase and the other effect was increasing the collision frequency of substrate-enzyme, and consequently, an increase in hydrolysis. 37 43 2015/02/162015/08/192014/11/252015/07/272015/07/28 1394/5/6 2015/06/292016/01/102015/11/112016/01/252016/01/25 1394/11/5 حسن صیامی H. Siami گروه شیمی دانشکده علوم ایران محمدرضا حسین‌دخت M.R. Housaindokht گروه شیمی دانشکده علوم/ مرکز پژوهش و فن‌اوری بیومولکول‌ ایران housain@um.ac.ir علی نخعی‌پور A. Nakhaei Pour گروه شیمی دانشکده علوم/ مرکز پژوهش و فن‌اوری بیومولکول‌ ایران Alpha-amylase Starch Ultrasound Activity Kinetic parameter. آمیلاز نشاسته فراصدا فعالیت پارامترهای جنبشی (سینتیکی). R. Kadkhodaee, M.J. Povey, "Ultrasonic inactivation of Bacillus α-amylase. I: Effect of gas content and emitting face of probe," Ultrasonics Sonochemistry, vol. 15, pp.133-142, 2008.##[2] C. Bendicho, I.D.L. Calle, F. Pena, M. Costas, N. Cabaleiro, I. Lavilla, "Ultrasound-assisted pretreatment of solid samples in the context of green analytical chemistry," Trac Trends in Analytical Chemistry, vol. 31, pp. 50-60, 2012.##[3] E.S. Beach, Z. Cui, P.T. Anastas, "Green chemistry: A design framework for sustainability," Energy and Environmental Science, vol. 2, pp. 1038-1049, 2009.##[4] O.E. Szabó, E. Csiszár, "The effect of low-frequency ultrasound on the activity and efficiency of a commercial cellulase enzyme," Carbohydrate Polymers, vol. 98, pp. 1483-1489, 2013.##[5] Z.M. Tian, M.X. Wan, S.P. Wang, J.Q. Kang, "Effects of ultrasound and additives on the function and structure of trypsin," Ultrasonics Sonochemistry, vol. 11, pp. 399-404, 2004.##[6] N. Gharat, V.K. Rathod, "Ultrasound assisted enzyme catalyzed transesterification of waste cooking oil with dimethyl carbonate," Ultrasonics Sonochemistry, vol. 20, pp. 900-905, 2013.##[7] H.R. Lobo, B.S. Singh, D.V. Pinjari, A.B. Pandit, G.S. Shankarling, "Ultrasound-assisted intensification of bio-catalyzed synthesis of mono-N-alkyl aromatic amines," Biochemical Engineering Journal, vol. 70, pp. 29-34 2013.##[8] C. Basto, T. Tzanov, A. Cavaco-Paulo, "Combined ultrasound-laccase assisted bleaching of cotton," Ultrasonics Sonochemistry, vol. 14, pp. 350-354, 2007.##[9] Z. Wang, X. Lin, P. Li, J. Zhang, S. Wang, H. Ma, "Effects of low intensity ultrasound on cellulase pretreatment," Bioresource Technology, vol. 117, pp. 222-227, 2012.##[10] E.X. Leaes, D. Lima, L. Miklasevicius, A.P. Ramon, V. Dal Prá, M.M. Bassaco, L.M. Terra, M.A. Mazutti, "Effect of ultrasound-assisted irradiation on theactivities of α-amylase and amyloglucosidase," Biocatalysis and Agricultural Biotechnology, vol. 2, pp. 21-25, 2013.##[11] V. Sivakumar, P.G. Rao, "Studies on the use of power ultrasound in leather dyeing," Ultrasonics Sonochemistry, vol. 10, pp. 85-94, 2003.##[12] P.C. Ashly, M.J. Joseph, P.V. Mohanan, "Activity of diastase α-amylase immobilized on polyanilines (PANIs)," Food Chemistry, vol. 127, pp. 1808-1813, 2011.##[13] D. Meridor, A. Gedanken, "Forming nanoparticles of α-amylase and embedding them into solid surfaces," Journal of Molecular Catalysis B: Enzymatic, vol. 90, pp. 43-48, 2013.##[14] G. Bayramoğlu, M. Yilmaz, M.Y. Arica, "Immobilization of a thermostable α-amylase onto reactive membranes: Kinetics characterization and application to continuous starch hydrolysis," Food Chemistry, vol. 84, pp. 591-599, 2004.##[15] O. Türünç, M.V. Kahraman, Z.S. Akdemir, N. Kayaman-Apohan, A. Güngör, "Immobilization of α-amylase onto cyclic carbonate bearing hybrid material," Food Chemistry, vol. 112, pp. 992-997, 2009.##[16] A. Kumari, A.M. Kayastha, "Immobilization of soybean (Glycine max) α-amylase onto Chitosan and Amberlite MB-150 beads: Optimization and characterization," Journal of Molecular Catalysis B: Enzymatic, vol. 69, pp. 8-14, 2011.##[17] V. Swarnalatha, R.A. Esther, R. Dhamodharan, "Immobilization of α-amylase on gum acacia stabilized magnetite nanoparticles, an easily recoverable and reusable support," Journal of Molecular Catalysis B: Enzymatic, vol. 96, pp. 6-13, 2013.##[18] P. Tripathi, A. Kumari, P. Rath, A.M. Kayastha, "Immobilization of α-amylase from mungbeans (Vigna radiata) on Amberlite MB 150 and chitosan beads: A comparative study," Journal of Molecular Catalysis B: Enzymatic, vol. 49, pp. 69-74, 2007.##[19] M. Sedaghat, M. Ghiaci, H. Aghaei, S. Soleimanian-Zad, "Enzyme immobilization. Part 3: Immobilization of α-amylase on Na-bentonite and modified bentonite," Applied Clay Science, vol. 46, no. 2, pp. 125-130, 2009.##[20] S. Aksoy, H. Tumturk, N. Hasirci, "Stability of α-amylase immobilized on poly (methyl methacrylate-acrylic acid) microspheres," Journal of Biotechnology, vol. 6, pp. 36-47, 1998.##[21] L. Cong, R. Kaul, U. Dissing, B. Mattiasson, "A model study on Eudragit and polyethyleneimine as soluble carriers of α-amylase for repeated hydrolysis of starch," Journal of Biotechnology, vol. 42, pp. 75-84, 1995.##[22] Y. Liu, S. Jia, J. Ran, S. Wu, "Effects of static magnetic field on activity and stability of immobilized α-amylase in chitosan bead," Catalysis Communications, vol. 11, pp. 364-367, 2010.##[23] M.I. Viseu, T.I. Carvalho, S.M. Costa, "Conformational transitions in beta-lactoglobulin induced by cationic amphiphiles: Equilibrium studies," Journal of Biophysics, vol. 86, pp. 2392-2402, 2004.##[24] H. Ma, L. Huang, J. Jia, R. He, L. Luo, W. Zhu, "Effect of energy-gathered ultrasound on Alcalase," Ultrasonics Sonochemistry, vol. 18, pp. 419-424, 2011.##[25] E.A. Permyakov, "Luminiescent Spectroscopy of Proteins," CRC Press Inc, Boca Raton, FL, Chapter 4, 1993.##[26] K.S. Suslick, "Ultrasound: Its Chemical, Physical and Biological Effects," VCH Publisher, 1988.## ##

مطالعه جابجایی‌های دامنه گسیل‌های صوتی حاصل اعوجاج گوش در پی مواجهه با سروصدا Study of distortion product otoacoustic emissions amplitude shifts following exposure to noise 1 1 مطالعه حاضر با هدف بررسی گسیل‌های صوتی حاصل اعوجاج در خوکچه‌های مواجهه‌یافته با سروصدا انجام شد. در این مطالعه 10 سر خوکچه هندی در دو گروه کنترل (بدون مواجهه با سروصدا) و گروه مواجهه با سروصدا (مواجهه با سروصدای سفید با تراز فشار صدای 95 دسی‌بل، 6 ساعت در روز، 5 روز در هفته برای مدت 2 هفته متوالی) در اتاقکی از جنس پلگسی‌گلاس مطالعه شدند. گسیل‌های صوتی حاصل اعوجاج گوش قبل از مواجهه و 2 هفته بعد از پایان مواجهه به منظور تثبیت آستانه دائم، با دستگاه تحلیل‌گر گسیل صوتی ثبت شدند. تفاوت معنا‌داری در دامنه‌های دی‌پی‌اُاِی‌ایی گروه کنترل در بسآمد‌های مورد بررسی یافت نشد، در حالی‌که، اختلاف معنا‌داری (با دامنه تغییرات 12/1 تا 24/6) بین دامنه‌های دی‌پی‌اُاِی‌ایی در تمام بسآمد‌های مورد بررسی، در گروه مواجهه با سروصدا، با بیش‌ترین و کم‌ترین افت در بسآمد‌های 3937 و 562 (به ‌ترتیب با 24/6 و 12/1 دسی‌بل) مشاهده شد. افت دامنه دی‌پی‌اُاِی‌ایی- ها در نتیجه مواجهه با سروصدا می‌تواند نشان‌دهنده‌ی اثرات نامطلوب سروصدا در کاهش عملکرد یاخته‌های مویی خارجی باشد. بنابراین حفاظت شنوایی در محیط‌های پر سروصدا ضروری است. 2 The aim of this study was assessment of Distortion Product Otoacoustic Emissions (DPOAE), in noise exposed guinea pigs. Ten guinea pigs in two control groups (without noise exposure) and a case group (that was exposed to a white noise with 95 dB SPL, 6h/d, 5d/wk for 2 consecutive weeks) were assessed in a Plexiglas cage. In order to stabilize permanent thresholds, DPOAEs before and two weeks after the last exposure were recorded by a DPOAEs analyzer. There is no significant difference in the control groups DPOAEs amplitude in the assessment frequencies, while in the noise exposed group a significant difference (with range 1.12- 6.24) was found between all the assessment frequencies, as the greatest and lowest decline was seen at 3937 and 562 frequencies (with 6.24 and 1.12 dB respectively). DPOAEs amplitude decline following noise exposure can indicate the noise adverse effects on outer hair cells function. Therefore hearing protection in noisy environments is necessary. 44 50 2015/02/162015/08/192014/11/252015/07/272015/07/282015/06/24 1394/4/3 2015/06/292016/01/102015/11/112016/01/252016/01/252016/02/9 1394/11/20 محمد رنجبریان M. Ranjbarian گروه مهندسی بهداشت حرفه‌ای، دانشکده بهداشت ایران mohammad_rangbarian@yahoo.com حامد ندری H. Nedri گروه مهندسی بهداشت حرفه‌ای، دانشکده بهداشت، ایران nadri_h@yahoo.com مهدی اکبری M. Akbari گروه شنوایی‌شناسی، دانشکده توان‌بخشی ایران akbari.usm@gmail.com علی خوانین A. Khavanin گروه مهندسی بهداشت حرفه‌ای، دانشکده علوم پزشکی ایران khavanin@modares.ac.ir اکرم پوربخت A. Pourbakht گروه شنوایی‌شناسی، دانشکده توان‌بخشی ایران pourbakht.a@iums.ac.ir DPOAE Noise Guinea Pig. دی‌پی‌اُاِی‌ایی سروصدا خوکچه هندی. [1] M. Sliwinska-Kowalska, A. Davis, "Noise-induced hearing loss," Noise and Health, vol. 14, no. 61, pp. 274-280, 2012##[2] A.S. Nordmann, B.A. Bohne, G.W. Harding, "Histopathological differences between temporary and permanent threshold shift," Hearing Research, vol. 139, no. 1, pp. 13-30, 2000.##[3] D. Yamashita, H-Y. Jiang, J. Schacht, J.M. Miller, "Delayed production of free radicals following noise exposure," Brain Research, vol. 1019, no. 1, pp. 201-209, 2004.##[4] A.C. Johnson, T.C. Morata, "The nordic expert group for criteria documentation of health risks from chemicals: 142. Occupational exposure to chemicals and hearing impairment," Arbets-och miljömedicin, University of Gothenburg, 2010.##[5] P. Mannström, "The effect of caloric restriction on age-related hearing loss and the impact of repeated sound exposure," Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden, 2013.##[6] J.J. Hawkins, "The role of vasoconstriction in noise-induced hearing loss," The Annals of Otology, Rhinology, and Laryngology, vol. 80, no. 6, pp. 903-913, 1971.##[7] C. Pierre, C.M. Thais, H. OiSaeng, "Chemical exposure and hearing loss," Disease-a-Month, vol. 24, pp. 119-138, 2013. ##[8] N. Cappaert, S. Klis, H. Muijser, B. Kulig, "Differential susceptibility of rats and guinea pigs to the ototoxic effects of ethyl benzene," Neurotoxicol Teratol, vol. 24, pp. 503-510, 2002. ##[9] R. Lataye, P. Campo, B. Pouyatos, B. Cossec, V. Blachère, G. Morel, "Solvent ototoxicity in the rat and guinea pig," Neurotoxicology and Teratology, vol. 25, no. 1, pp. 39-50, 2003.##[10] P.W. Alberti, "The Anatomy and Physiology of the Ear and Hearing," University of Toronto 2001. ##[11] D. Kemp, "Otoacoustic emissions, their origin in cochlear function, and use," British Medical Bulletin, vol. 53, pp. 223-241, 2002.##[12] V. Atchariyasathian, S. Chayarpham, S. Saekhow, "Evaluation of noise-induced hearing loss with audiometer and distortion product otoacoustic emissions," Medical Journal of The Medical Association of Thailand, vol. 91, no. 7, pp. 1066-1071, 2008.##[13] N. Seixas, S. Kujawa, S. Norton, L. Sheppard, R. Neitzel, A. Slee, "Predictors of hearing threshold levels and distortion product otoacoustic emissions among noise exposed young adults," Occupational and Environmental Medicine, vol. 61, no. 11, pp. 899-907, 2004.##[14] A. Desai, D. Reed, A. Cheyne, S. Richards, D. Prasher, "Absence of otoacoustic emissions in subjects with normal audiometric thresholds implies exposure to noise," Noise and Health, vol. 1, no. 2, pp. 58-65, 1999.##[15] J. Attias, M. Furst, V. Furman, I. Reshef, G. Horowitz, I. Bresloff, "Noise-induced otoacoustic emission loss with or without hearing loss," Ear and Hearing, vol. 16, no. 6, pp. 612-618, 1995.##[16] D. Prasher, W. Sułkowski, "The role of otoacoustic emissions in screening and evaluation of noise damage," International Journal of Occupational Medicine and Environmental Health, vol. 12, no. 2, pp. 183-192, 1995.##[17] S. Soliman, M. El-Atreby, S. Tawfik, E. Holail, N. Iskandar, A. Abou-Setta, "The interaction of whole body vibration and noise on the cochlea," International Congress Series, vol. 1240, pp. 209-216, 2003.##[18] M.P. Gorga, S.T. Neely, P.A. Dorn, "Distortion product otoacoustic emissions in relation to hearing loss," Otoacoustic emissions: Clinical applications, pp. 243-272, 2002.##[19] G.A. Manley, R.R. Fay, A.N. Popper, "Active Processes and Otoacoustic Emissions in Hearing," Springer, 2008. ##[20] G.W. Harding, B.A. Bohne, M. Ahmad. "DPOAE level shifts and ABR threshold shifts compared to detailed analysis of histopathological damage from noise," Hearing Research, vol. 174, no. 1, pp. 158-171, 2002.##[21] E. Emmerich, F. Richter, U. Reinhold, V. Linss, W. Linss, "Effects of industrial noise exposure on distortion product otoacoustic emissions (DPOAEs) and hair cell loss of the cochlea-long term experiments in awake guinea pigs," Hearing Research, vol. 148, no. 1, pp. 9-17, 2000.##[22] SA. Moussavi-Najarkola, A. Khavanin, R. Mirzaee, M. Salehnia, M. Akbari, H. Asilian, "Study of noise effects on rabbit's hearing status using distortion product otoacoustic emissions," Audiology, vol. 20, no. 2, pp. 113-124, 2011. ##[23] R. Heffner, H. Heffner, B. Masterton, "Behavioral measurements of absolute and frequency‐difference thresholds in guinea pig," The Journal of the Acoustical Society of America, vol. 49, no. 6B, pp. 1888-1895, 1971. ##[24] A. Brown, "Acoustic distortion from rodent ears: A comparison of responses from rats, guinea pigs and gerbils," Hearing Research, vol. 31, no. 1, pp. 25-37, 1987.##[25] B. Davis, W. Qiu, R.P. Hamernik, "The use of distortion product otoacoustic emissions in the estimation of hearing and sensory cell loss in noise-damaged cochleas," Hearing Research, vol. 187, no. 1, pp. 12-24, 2004.##[26] E. Emmerich, F. Richter, V. Linss, W. Linss, "Frequency-specific cochlear damage in guinea pig after exposure to different types of realistic industrial noise," Hearing Research, vol. 201, no. 1, pp. 90-98, 2005. ##[27] P. Plinkert, W. Hemmert, W. Wagner, K. Just, H. Zenner, "Monitoring noise susceptibility: Sensitivity of otoacoustic emissions and subjective audiometry," British Journal of Audiology, vol. 33, no. 6, pp. 367-382, 1999. ##[28] J. Attias, G. Horovitz, N. El-Hatib, B. Nageris, "Detection and clinical diagnosis of noise-induced hearing loss by otoacoustic emissions," Noise and Health, vol. 3, no. 12, pp. 19-31, 2001. ##[29] M.E. Boger, A. Sampaio, C. Oliveira, "Otoacoustic emissions in normal-hearing workers exposed to different noise doses," The International Tinnitus Journal, vol. 17, no. 1, pp. 74-79, 2012. ## ##

بررسی اثر استفاده از امواج فراصدا بر برخی ویژگی‌های فیزیکی-شیمیایی و حسی گوشت مارینادشده با اسید لاکتیک Analyzing ultrasound effect on physical-chemical properties and evaluation sensory of marinated meat with lactic acid 1 1 استفاده از امواج فراصدا در فرآیند ماریناد کردن یکی از روش‌های جدید در جهت کاهش زمان این فرآیند و بهبود ویژگی‌های گوشت مارینادشده ‌می‌باشد. در تحقیق حاضر قطعات مکعبی شکل گوشت با ابعاد 5/2 به مدت 30 دقیقه با شدت‌‌های 5، 8 و 12 وات بر سانتی‌متر مربع تحت تیمار امواج فراصدا قرار گرفتند. سپس توسط اسید لاکتیک 2/0 مولار به مدت 8 و 16 ساعت ماریناد شدند. میزان جذب ماریناد و پی‌اچ (pH) نمونه‌ها اندازه‌گیری شدند و عملیات پخت در حمام آب گرم در دمای 4 ± 90 سلسیوس انجام شد. پس از آن، افت پخت، پی‌اچ (pH)، تغییرات رنگ و نیروی لازم جهت برش نمونه‌ها مورد بررسی قرار گرفتند. نتایج نشان دادند امواج فراصدا تأثیر معنا‌داری بر پی‌اچ (pH) نمونه‌ها ندارند. اِعمال امواج فراصدا سبب افزایش معنا‌دار جذب ماریناد نمونه‌ها نسبت به نمونه شاهد می‌شود. هم‌چنین، درصد افت پخت در شدت 5 وات بر سانتی‌متر مربع از سایر شدّت‌‌ها و نمونه شاهد کم‌تر شد. ضمناً، نیروی لازم جهت برش، تغییرات رنگ نسبت به نمونه شاهد تفاوت آماری معنا‌داری (05/0p <) را نشان می‌دهند. به لحاظ ایجاد تردی، تأثیر روی رنگ و افت پخت، با افزایش زمان ماریناد کردن، در ویژگی‌‌های فوق بهبود حاصل می‌شود. اگر چه از نظر حسی، مدّت ماریناد کردن تأثیر معنا‌‌داری روی تردی، رنگ و آب‌دار بودن ندارد. 2 The use of ultrasound waves in the processes of marination is a new method to reduce time duration of marinating and improve the characteristics of meat. In this research, 2.5×2.5×2.5 cm cubic meat samples were treated by 20 kHz ultrasound waves for 30 minutes with intensities 5, 8, and 12 W/cm2. Then the meat samples were marinated by molar lactic acid for 8 and 12 hours. Acid absorption and pH parameter were measured and then cooking process in hot water bath took place at 90±4°C. Afterward, cooking loss, pH, color change and tenderness were analyzed. The results showed no significant differences in pH values between the ultrasound-treated meat and the control samples. The ultrasound treatment has significant effect on acid absorption. At intensity of 5 W/cm2, tenderness increases and color changes significantly with less cooking loss from others. By increasing marinating time duration, color, cooking loss, and tenderness features improve and it has no significant effects on the sensory evaluation. 51 60 2015/02/162015/08/192014/11/252015/07/272015/07/282015/06/242015/09/4 1394/6/13 2015/06/292016/01/102015/11/112016/01/252016/01/252016/02/92015/12/31 1394/10/10 نجمه شمس N. Shams دانشکده علوم و مهندسی صنایع غذایی، واحد علوم و تحقیقات ایران shams90.fi@gmail.com سیدابراهیم حسینی S.E. Hoseini دانشکده علوم و مهندسی صنایع غذایی، واحد علوم و تحقیقات ایران Ebhoseini@srbiau.ac.ir غلامحسین اسدی G.H. Asadi دانشکده علوم و مهندسی صنایع غذایی، واحد علوم و تحقیقات ایران asadi@srbiau.ac.ir Ultrasound Meat Marinade Tenderness pH Color Cooking loss Sensory evaluation. فراصدا گوشت گوساله ماریناد کردن تردسازی پی‌اچ (pH) رنگ افت پخت ارزیابی حسی. [1] T. Goli, J. Ricci, P. Bohuonb, S. Marchesseauc, A. 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الگو‌سازی و ارزیابی تجربی کاهنده‌های نوفه برای سامانه‌های حسگری طیفی پایین- بسامد Modeling and empirical evaluation of noise reducers for low-frequency acoustical spectrum sensing system 1 1 در این مقاله مسئله ارزیابی روش الگوسازی برقی صافی‌های صوتی پایین- بسامد مطالعه می‌گردد. در همین راستا پس از مرور مبانی روش الگو‌سازی برقی صافی‌های صوتی، عناصر صوتی پایه با عناصر برقی متناظر معادل‌سازی شده‌ و با تشکیل یک مدار معادل با صافی‌های صوتی موردنظر، تابع تبدیل کل مدار تعیین شده‌است. به‌منظور ارزیابی کارایی روش الگوسازی پیشنهادشده، نمونه‌ای از یک صافی صوتی طراحی و در میدان ساخته‌شده و با اتصال به سامانۀ حسگری اکتساب داده‌ها، در شرایط واقعی اقدام به داده‌برداری گردید. درنهایت، نتایج داده‌برداری‌ سامانه مذکور با نتایج شبیه‌سازی به روش الگوسازی برقی مقایسه‌ و ارائه گردیدند. نتایج تأیید می‌کنند که روش الگوسازی پیشنهادی می‌تواند با خطای قابل قبولی خروجی‌های واقعی را شبیه‌سازی نماید. 2 This paper studies the performance of electro-acoustical modeling technique for mechanical noise reducers in low-frequency applications. To this end, firstly we introduce the electrical equivalents of fundamental acoustic elements and then, propose an equivalent circuit for the entire noise reduction system, which enables us to derive its overall frequency response. In order to validate the proposed modeling method, we implement the complete acoustical sensing system in real environment and compare its performance with simulated mathematical model. Empirical results confirm the proposed modeling technique for acoustical noise-reduction spectrum sensing applications. 61 71 2015/02/162015/08/192014/11/252015/07/272015/07/282015/06/242015/09/42015/11/4 1394/8/13 2015/06/292016/01/102015/11/112016/01/252016/01/252016/02/92015/12/312016/03/5 1394/12/15 سعید خدامی S. KHodami دانشکده مهندسی مکانیک ایران ebnesina@outlook.com حامد صادقی H. Sadeghi آزمایشگاه مخابرات بی‌سیم، دانشکده مهندسی برق و کامپیوتر ایران h.sadeghi@mail.ru عباس رمضانی قائمی A. Ramazani Ghaemi دانشکده فنی و مهندسی رسانه ایران e_ramezani2006@yahoo.com Noise-reduction filter Acoustical spectrum sensing Low-frequency Sound. صافی صوتی حسگر طیفی صوتی بسامد- پایین صدا. [1] A. Keiling, D.N. Lee, V. Nakariakov, "Low-Frequency Waves in Space Plasmas," John Wiley and Sons, 2016.##[2] N. Popper, A. Hawkins, "The Effects of Noise on Aquatic Life II," Springer, 2015.##[3] R.W. Whitaker, "Infrasonic Monitoring," In Phillips Lab Monitoring Symposium, USA, 1995.##[4] D. Christie, P. Campus, "The IMS infrasound network: Design and establishment of infrasound stations," Infrasound Monitoring for Atmospheric Studies, 2010.##[5] A.E. Gelfand, P.J. Diggle, P. Guttorp, “Handbook of Spatial Statistics,” Taylor and Francis Group, London, 2010.##[6] G.I. Taylor, "The spectrum of turbulence," Proceedings Royal Society, vol. A164, pp. 476-490, 1938.##[7] K.T. Walker, M.A.H. Hedlin, "A review of wind-noise reduction methodologies," Infrasound Monitoring for Atmospheric Studies, 2010.##[8] F.B. Daniels, "Noise-reducing line microphone for frequencies below 1 cps," Journal of the Acoustical Society of America, vol. 31, pp. 529, 1959.##[9] R. Burridge, "The acoustics of pipe arrays," Geophysical Journal of the Royal Astronomical Society, vol. 26, pp. 53-69, 1971.##[10] F.H. Grover, "Experimental noise reducers for an active microbarograph array," Geophysical Journal of the Royal Astronomical Society, vol. 26, pp. 41-52, 1971.##[11] B. Alcoverro, "Acoustic filters design and experimental results," Commissariat à Energie, Bruyères-le-Châtel, Proceedings Workshop on Infrasound, France, pp. 21–24, 1998.##[12] B. Alcoverro, A.L. Pichon, "Design and optimization of a noise reduction system for infrasonic measurements using elements with low acoustic impedance," Journal of Acoustical Society of America, vol. 117, pp. 1717–1727, 2005.##[13] M.H. Hedlin, R. Raspet, "Infrasonic wind noise reduction by barriers and spatial filters," Journal of Acoustical Society of America, vol. 114, pp. 1379-1386, 2003.##[14] J.M. Noble, R. Raspet and others, "Wind Noise Suppression for Infrasound Sensors," Army Research Laboratory, USA, MD 20783-1197, 2014.##[15] S.L. Collier, R. Raspet, J.M. Noble, J. Webster "Analysis of wind noise reduction by semi-porous fabric domes," Journal of Acoustical Society of America, 2014.##[16] M.H. Hedlin, B. Alcoverro "The use of impedance matching capillaries for reducing resonance in rosette infrasonic spatial filters," Journal of Acoustical Society of America, vol. 117, pp. 1880-1888, 2005.##[17] T.M. Marston, "Infrasonic Pistonphone Calibration," PhD Thesis, Pennsylvania State University, USA, 2009.##[18] G.P. Scavone, "An acoustic analysis of single-reed woodwind instruments with an emphasis on design and performance issues and digital waveguide modeling techniques," PhD Thesis, Department of Music, Stanford University, 1997.## ##