scholarly journals Natural frequency as a nondestructive biophysical changes assessment of tropical fruits: Case study of durian (Durio zibethinus), mango (Mangifera indica), and “sawo”(Arachaszapota)

2021 ◽  
Author(s):  
Y. Yuwana ◽  
E. Silvia
Keyword(s):  
Natural Frequency ◽  
Mangifera Indica ◽  
Tropical Fruits ◽  
Durio Zibethinus ◽  
Biophysical Changes

INVESTIGATIONS ON FORAGE YIELD OF OAT GENOTYTPES UNDER IRRIGATED CONDITIONS OF KONYA

2021 ◽  
Vol 9 (2) ◽  
pp. 85-88
Author(s):  
Muhammad Ahsan Qureshi ◽  
Waqar Shafqat
Keyword(s):  
Mangifera Indica ◽  
Forage Yield ◽  
Root Induction ◽  
Shoot Induction ◽  
Tropical Fruits ◽  
Asexual Propagation ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
High Concentrations ◽  
Direct Shooting

Shoot tips of newly emerging mango shoots were used as an explant and cultured on MS media for direct shooting. Different plant growth regulators i.e. BAP, NAA and IAA in varying concentrations were added to basal MS media. Experiment was laid out according to Completely Randomized Design (CRD) with four treatments and each treatment was replicated thrice. Maximum shoot induction (55.56%) was observed with 1 mg/L of BAP. Maximum mortality (83.30%) was observed when maximum concentration of BAP (3 mg/L) was used. Minimum days (12.633) to induce shoots were observed on MS media supplemented with 1 mg/L of BAP. Maximum number of shoots (2.50) were recorded in MS media supplemented with 1 mg/L of BAP. Low concentration of NAA initiated roots earlier in regenerated shoots as compare to high concentrations of NAA and IAA. MS media supplemented with NAA (1 mg/L) took less days (21 days) to induce roots. The combination of auxins (MS+ NAA 3 mg /L + IAA 1 mg /L) proved the best for root induction (38.87%). Keywords: Mangifera indica, tropical fruits, asexual propagation, plant tissue culture, micropropagation, phenolic exudation, acclimatization.

scholarly journals A Case Study of Natural Frequency of the Tram Rail Due to Vibration Using Wavelets

2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Pushan Kumar Dutta ◽  
Mircea Bogdan Tătaru ◽  
Ovidiu Moldovan ◽  
Tiberiu Vesselenyi
Keyword(s):  
Natural Frequency

An Objective Evaluation of Displacement-Amplifying Compliant Mechanisms for Sensor Applications

2006 ◽  
Author(s):  
Girish Krishnan ◽  
G. K. Ananthasuresh
Keyword(s):  
Natural Frequency ◽  
Compliant Mechanisms ◽  
Selection Procedure ◽  
Force Sensor ◽  
Objective Evaluation ◽  
Performance Criteria ◽  
Sensor Applications ◽  
Capacitive Accelerometer ◽  
General Evaluation

Displacement-amplifying compliant mechanisms (DaCMs) reported in literature are mostly used for actuator applications. This paper considers them for sensor applications that rely on displacement measurement, and evaluates them objectively. The main goal is to increase the sensitivity under constraints imposed by several secondary requirements and practical constraints. A spring-mass-lever model that effectively captures the addition of a DaCM to a sensor is used in comparing eight DaCMs. We observe that they significantly differ in performance criteria such as geometric advantage, stiffness, natural frequency, mode amplification, factor of safety against failure, cross-axis stiffness, etc., but none excel in all. Thus, a combined figure of merit is proposed using which the most suitable DaCM could be selected for a sensor application. A case-study of a micro machined capacitive accelerometer and another case-study of a vision-based force sensor are included to illustrate the general evaluation and selection procedure of DaCMs with specific applications. Some other insights gained with the analysis presented here were the optimum size-scale for a DaCM, the effect on its natural frequency, limits on its stiffness, and working range of the sensor.

Evaluation on Environmental Corrosion Damage of Steel Domes

2010 ◽  
Vol 44-47 ◽  
pp. 163-167
Author(s):  
Bo Chen ◽  
Jian Feng Wei ◽  
Jin Zheng
Keyword(s):  
Natural Frequency ◽  
Corrosion Damage ◽  
Exponential Model ◽  
Nonlinear Static Analysis ◽  
Space Structures ◽  
Structural Members ◽  
Nonlinear Static ◽  
Corrosion Of Steel

The evaluation on environmental corrosion damage of steel domes is carried out in this study through an integration of knowledge in material science and structural analysis. The refined exponential model for estimating corrosion of steel materials is presented based on long-term experimental data available. The formula for relating structural natural frequency sensitivity to structural member thickness is then derived to assess the sensitivity of natural frequency to variation of member thickness due to corrosion. The nonlinear static analysis is conducted to evaluate effects of atmospheric corrosion on the stress of structural members and the safety of steel space structures. A real steel dome built in China is taken as the case study to examine the feasibility of the proposed approach and to assess the potential corrosion damage to the structure..

scholarly journals INVENTARISASI HASIL HUTAN BUKAN KAYU PADA TANAMAN MPTS DI HUTAN DESA SUKARAJA KPH RAJABASA

2020 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Ani Fitriyani ◽  
Melya Riniarti ◽  
Duryat Duryat
Keyword(s):  
Random Sampling ◽  
Mangifera Indica ◽  
Forest Products ◽  
Simple Random Sampling ◽  
Agroforestry System ◽  
Persea Americana ◽  
Durio Zibethinus ◽  
The People ◽  
Non Timber Forest Products ◽  
Gnetum Gnemon

ABSTRAK Hutan Desa Sukaraja merupakan hutan lindung yang dimanfaatkan oleh masyarakat melalui pengelolaan dengan sistem agroforestri dan pemungutan hasil hutan bukan kayu untuk meningkatkan kesejahteraan masyarakat. Penelitian ini bertujuan untuk memperoleh data mengenai jenis dan jumlah HHBK dari tanaman MPTs serta menduga potensi HHBK dari tanaman MPTs pada masa yang akan datang berdasarkan ketersediaannya di masa kini. Data dikumpulkan melalui analisis vegetasi pada 29 plot contoh yang diambil berdasarkan metode SRS (Simple Random Sampling). Untuk memprediksi penambahan jumlah MPTs 1 sampai 4 tahun yang akan datang dilakukan pengamatan pohon pada fase tiang dan pancang. Hasil penelitian menunjukkan terdapat 11 jenis tanaman MPTs yang dimanfaatkan hasil hutan bukan kayunya oleh masyarakat Desa Sukaraja yaitu durian, cengkeh, pala, petai, alpukat, kemiri, mangga, nangka, jengkol, melinjo dan duku. Hasil penelitian menunjukkan bahwa hingga beberapa tahun yang akan datang pohon cengkeh dan durian masih menjadi MPTs yang paling banyak dimanfaatkan dan ditanam oleh masyarakat. Sedangkan mangga dan kemiri merupakan HHBK yang produksinya akan stagnan atau bahkan mengalami penurunan dalam kurun waktu 1-4 tahun yang akan datang. Kata Kunci : HHBK, MPTs, Hutan Desa, KHP Rajabasa  ABSTRACT Sukaraja Village Forest is a protected forest that is utilized by the community through agroforestry system and collection of non-timber forest products to improved community welfare. This study aimed to obtain data on the types and numbers of NTFPs from MPTs and to estimate the potential of NTFPs from MPTs in the future based on their availability in the present. Data was collected through vegetation analysis with 29 sample plots taken based on the SRS (Simple Random Sampling) method. To predict the increase of amount of MPTs in 1-4 years, observed of trees in the pole and sapling phases. The results showed that there were 11 types of MPTs that were utilized by non-timber forest products by the people of Sukaraja Village, that were Durio Zibethinus, Eugenis aromaticum, Phitecellobium lobatum, Parkia spesiosa, myristica fragnans, Artocarpus heterophyllus, Lansium domesticum, Persea americana, Alueuritas moluccanus, Gnetum gnemon and Mangifera indica. The results showed that for the next few years Eugenia aromaticum and Durio zibethinus trees were still the most widely used and planted by the community. While production of Mangifera indica and Alleurites moluccanus were the NTFPs that will be stagnate or even decline in the next 1-4 years. Keywords : NTFPs, MPTs, Village Forest, KPH Rajabasa

scholarly journals VIBRATIONAL CASE STUDY FOR THE MOLD OSCILLATOR WITH HYDRAULIC SERVO SYSTEM

2019 ◽  
Vol 25 (2) ◽  
Author(s):  
PARK YONGHUI ◽  
LEE CHANGWOO ◽  
KIM DONGWOOK
Keyword(s):  
Natural Frequency ◽  
Servo System ◽  
Hydraulic Cylinder ◽  
Design Parameters ◽  
Natural Mode ◽  
Hydraulic Servo ◽  
Hydraulic Servo System ◽  
Mold Oscillator ◽  
The One

<p>We have conducted sensitivity analysis to investigate the two-hydraulic-servo system for the mold oscillator. By modelling mathematical models for operating fluid flow to control a hydraulic cylinder, we changed design parameters and environment conditions including friction, additional spring stiffness and fluid leakage. From the one-hydraulic servo system to the two-hydraulic cylinder, modal analysis was conducted to figure out dynamic characteristics of the real system. Especially, we categorized important natural mode shape. When the system was excited into the natural frequency, the 1st mechanical natural frequency could cause a pressure gain by reducing internal pressure of a hydraulic cylinder, but other natural frequencies were critically dangerous by generating imbalance, over-vibration and distortion. By comparing the results to the experimental data, we could find a dramatic pressure drop near 3 Hz oscillation when the system has the 1st mechanical natural frequency 2.499 Hz. Also, the system has the imbalance near 6 Hz oscillation when the system has 2nd mechanical natural frequency 5.446 Hz. Based on these fact, we have suggested some tips to oscillate a mold efficiently and safely.</p>

Model-Based Installation of Viscoelastic Damper Support for Reduction of Residual Vibration

2018 ◽  
Vol 12 (5) ◽  
pp. 650-657
Author(s):  
Kotaro Mori ◽  
Daisuke Kono ◽  
Iwao Yamaji ◽  
Atsushi Matsubara ◽  
◽  
...  
Keyword(s):  
Natural Frequency ◽  
Low Frequency ◽  
Damping Capacity ◽  
System Support ◽  
Model Based ◽  
Machining Center ◽  
Stiffness Model ◽  
Rocking Vibration ◽  
The Relationship

It is necessary to increase the damping of a machine support structure (support damping) to reduce the residual vibrations caused by rocking vibration. The stiffness of the machine support system (support stiffness) is also an important parameter that needs to be considered while designing machine tools, to avoid low frequency vibrations. However, conventional passive damper supports decrease the support stiffness while increasing the damping. In our previous study, a passive viscoelastic non-linear damper system for shear vibrations, where the vertical preload determines its damping coefficient, was developed to increase the support damping without decreasing the stiffness by focusing on the horizontal component of rocking vibration. The magnitude dependency of the damping capacity has been modeled. However, this damper system has a tradeoff relationship between natural frequency and damping capacity caused by changes in the preload distribution. Thus, adjustment of the vertical preload applied on the damper is essential for the model-based installation of this damper system. So far, no method has been proposed considering this issue. The vertical preload has been adjusted by trial and error methods. This study proposes a method to determine the damper preload conditions systematically by considering the tradeoff relationship between natural frequency and damping capacity caused by changes in the preload distribution. This method is described based on the case study of a machining center. First, the relationship between preload distribution and support stiffness is investigated using the support stiffness model. Then, the relationship between damping capacity and vertical preloads on the damper is investigated based on material test results. Based on these investigations, the tradeoff relationships are simulated on a machining center by utilizing the damper model. The simulation results are verified with the experimental results. The results show that the proposed method can estimate the tradeoff relationship between natural frequency and damping capacity caused by the changes in the preload distribution. By utilizing this estimated relationship, the preferred preload condition can be decided depending upon the user’s demand.

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