Effects of two plant waxes as a coating material on internal attributes of chicken eggs stored under room temperature

( Herath Mudiyansalage Nuwan Chaminda Ratnayake ),( Herath Mudiyanselage Jagath Chaminda Pitawala ),( Edirisinghe Dewage Nalaka Sandun Abeyrathne ) 한국축산학회 2021 축산기술과 산업 Vol.8 No.2

Surface coatings of eggs are used to extend the shelf life and minimize economic loss. Edible mineral oil is used as a coating material but several problems associated with it and plant waxes are tested as alternatives. “Boomi” (Litsea glutinosa) and “dawul kurundu” (Neolitsea cassia) is found throughout Sri Lanka and barks of these trees are widely used in indigenous medicine due to their antibacterial properties. But, information on these waxes on egg quality attributes does not exist. Objective of this research was to check the effect of “boomi” and “dawul kurundu” waxes as an external coating material on shelf life and internal quality of chicken eggs stored under room temperature. Total of 372 freshly laid brown, medium sized (55-60 g), clean eggs were purchased from a layer farm. Eggs were individually weighed and coated with “boomi” wax (1.0:6.5), “dawul kurundu” wax (01:10) and mineral oil while non coated eggs were used as negative control. Weight loss, change in air sac volume, Haugh unit (HU), yolk color, albumen and yolk pH, yolk index and FTIR analysis were determined at weekly basis for 6 weeks. Albumen and yolk pH increased with storage. But it is significantly lower in mineral coated eggs (p < 0.05). Whereas HU and yolk index decreased during storage in wax coated and non-coated eggs (p < 0.05). Grades of non-coated, “boomi” wax coated and “dawul kurundu” wax coated eggs were changed from AA to B within 4 weeks whereas in mineral oil coated eggs (MO) remain in AA. Weight loss of wax coated eggs were significantly higher compared to MOs (p < 0.05). FTIR analysis revels that the no chemical changes occur due to the wax. Increase of air sac was higher in noncoated eggs (5.39 ± 0.3 mm) after 42 days compared to “boomi” wax (4.59 ± 0.2 mm), “dawul kurundu” wax (3.27 ± 0.3 mm) and mineral oil (1.19 ± 0.3 mm) coated eggs. Thus, study showed that these two plant waxes had better qualities than non-coated eggs but less than the MOs.

Challenges in transforming the collection, pre- process and end use of e-waste from informal sector to formal sector in Sri Lanka

( Janaka Chaminda Wijesekera ),( Yasantha Gunarathna ),( Heshan Demuni ) 한국폐기물자원순환학회 2022 ISSE 초록집 Vol.2022 No.-

Sri Lanka has an increasing demand for scientific and organized e-waste management system over the years. Sri Lanka has signed BASEL Convention for Transboundary Movement of Hazardous Waste. At present the Country exports e-waste to South Korea, Japan, Singapore, and Europe in accordance with the international guidelines. However, majority of the current e-waste arrangements in the Country revolve around the informal sector. These informal arrangements have resulted in hazards to the environment and the society due to unscientific mechanisms of processing the respective waste. Therefore, it is vital to transform the e-waste management from informal to formal sector without adversely impacting the livelihood of those involved with the informal sector, mainly in collecting and disassembling (pre-processing) of the end of life electric and electronic items. The key objective of this study is to identify the current context, issues encountered in collecting e-waste and challenges faced by all stakeholders to establish a sustainable system. The methodology consists of available literature, site visits, direct interviews with stakeholders including regulators, collectors in different levels and registered e waste exporters. Findings of this highlighted that informal sector as the dominant party has been causing material losses and pollution due to preprocessing of e-waste without following proper environmental safety concerns, barriers and limitations to the formal sector to enter the market and highly competition among exporters. The research suggests developing mechanisms to offer reasonable rates for the front-end collectors to secure their livelihood through the earnings from exports while facilitate to gap financing of reverse logistic via Extended Producer Responsibility scheme. Instead of attracting and sourcing the unscientifically dismantled items, the e-waste exporters are required to develop infrastructure for proper disassembling, treatment and promote the informal sector to facilitate ‘Reverse Logistics’. The gap financing to be done through an ‘Extended Producer Responsible Scheme’. This would help proper management of the e-waste while ensuring continuation of the livelihood of those contributors in the informal sector.

Outage Probability for Cooperative Nano Communication in the THz Gap Frequency Range

( A. Chaminda J. Samarasekera ),( Hyundong Shin ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.1

Nanotechnology has provided a set of tools that the engineers can use to design and manufacture integrated nano devices, which are capable of performing sensing, computing, data storing and actuation. One of the main hurdles for nano devices has been the amount of power that it can generate for transmission of data. In this paper, we proposed cooperative nano communication in the Terahertz (THz) Gap frequency band to increase the range of transmission. Outage probability (OP) performances for the proposed cooperative nano communication networks in the THz band (0.1 - 10THz) have been evaluated for the following scenarios; A) A single decode-and-forward (DF) relay over independent identically distributed (i.i.d.) Rayleigh fading channels, B) DF multi-relay network with best relay selection (BRS) over i.i.d. Rayleigh fading channels, and C) DF multi-relay network with multiple hops with BRS over i.i.d. Rayleigh fading channels. The results show that the transmission distance can be improved significantly by employing DF relays. Also, it is shown that by increasing the number of hops in a relay the OP performance is marginally degraded. The analytical results have been verified by Monte-Carlo simulation.

Cooperative Nano Communication in the THz Gap Frequency Range using Wireless Power Transfer

( A. Chaminda J. Samarasekera ),( Hyundong Shin ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.10

Advancements in nanotechnology and novel nano materials in the past decade have provided a set of tools that can be used to design and manufacture integrated nano devices, which are capable of performing sensing, computing, data storing and actuation. In this paper, we have proposed cooperative nano communication using Power Switching Relay (PSR) Wireless Power Transfer (WPT) protocol and Time Switching Relay (TSR) WPT protocol over independent identically distributed (i.i.d.) Rayleigh fading channels in the Terahertz (THz) Gap frequency band to increase the range of transmission. Outage Probability (OP) performances for the proposed cooperative nano communication networks have been evaluated for the following scenarios: A) A single decode-and-forward (DF) relay for PSR protocol and TSR protocol, B) DF multi-relay network with best relay selection (BRS) for PSR protocol and TSR protocol, and C) DF multi-relay network with multiple DF hops with BRS for PSR protocol and TSR protocol. The results have shown that the transmission distance can be improved significantly by employing DF relays with WPT. They have also shown that by increasing the number of hops in a relay the OP performance is only marginally degraded. The analytical results have been verified by Monte-Carlo simulations.

Cognitive Multiple-Hop Relay Networks in Weibull Fading

A. Chaminda J. Samarasekera,Hyundong Shin 한국통신학회 2014 한국통신학회 학술대회논문집 Vol.2014 No.6

Different Approaches for Remaining Fatigue Life Estimation of Critical Members in Railway Bridges

Siriwardane Sudath Chaminda,Mitao Ohga,Ranjith Dissanayake,Kazuhiro Taniwaki 한국강구조학회 2007 International Journal of Steel Structures Vol.7 No.4

Rail authorities all over the world are paying atractive atentions to evaluate the remaing fatigue lives of riveted railwaybridges since most of these bridges are curently reaching the ends of their theoretical fatigue lives. This paper proposes threediferent approaches to evaluate remaining fatigue life of an existing riveted railway bridge. First proposed approach is basedconsists of measured stress histories, recently developed sequential law and fully known Whler curve. The both mentionedapproaches are specially based on evaluation of primary streses and code provided fatigue curve. Therefore, proposed thirdapproach is anchored in secondary (local) stresses, sequential law and experimental Whler curve. Finaly the obtained fatiguelives are compared. Thus, it has been concluded that the second approach is more advisable for general use and third approachhas been recomended for detail studies.

Retrofitting of damaged bridges – the sustainable solution

Ranjith Dissanayake,Chaminda S. Bandara 서울시립대학교 도시과학연구원 2016 도시과학국제저널 Vol.20 No.2

Rehabilitation of damaged bridges may be more beneficial than building new bridges. However, proper methods are necessary to assess the level of damages and to verify the fitness of such bridges for further use. In the assessment, there are two important criteria to consider. One is the amount of damage due to fatigue caused by usual past vehicle loading and the other is the magnitude of damage caused by the unexpected actions. The present paper is about a wrought iron bridge damaged by floods. In order to do the assessment, a condition survey was first carried out. Then an analysis was done using a finite element model of the bridge. The model was validated using results of a field loading test. Both static and dynamic loading tests were conducted using a locomotive with six numbers of 13.16-ton axles for five different loading cases to measure the displacement, strain and acceleration at predetermined (critical) members of the bridge. Then the damage in the bridge due to past loading histories and the future fatigue life of the bridge were estimated. Furthermore, using the validated model, the ability of the bridge for higher loading situations was confirmed. The future life was found as 30 years with a factor of safety of 3. The cost estimated for retrofitting work and constructing new reinforced concrete abutments was much less than that for constructing a new bridge. Therefore, it was decided that the rehabilitation of the bridge with necessary retrofitting work is more economical and sustainable than demolishing it and constructing a new one. The bridge is now in use after being repaired, retrofitted and placed on new abutments.

Assessment of recycled concrete aggregates as a pavement material

Jayakody, Shiran,Gallage, Chaminda,Kumar, Arun Techno-Press 2014 Geomechanics & engineering Vol.6 No.3

Population increase and economic developments can lead to construction as well as demolition of infrastructures such as buildings, bridges, roads, etc resulting in used concrete as a primary waste product. Recycling of waste concrete to obtain the recycled concrete aggregates (RCA) for base and/or sub-base materials in road construction is a foremost application to be promoted to gain economical and sustainability benefits. As the mortar, bricks, glass and reclaimed asphalt pavement (RAP) present as constituents in RCA, it exhibits inconsistent properties and performance. In this study, six different types of RCA samples were subjected classification tests such as particle size distribution, plasticity, compaction test, unconfined compressive strength (UCS) and California bearing ratio (CBR) tests. Results were compared with those of the standard road materials used in Queensland, Australia. It was found that material type 'RM1-100/RM3-0' and 'RM1-80/RM3-20' samples are in the margin of the minimum required specifications of base materials used for high volume unbound granular roads while others are lower than that the minimum requirement.

Anti-inflammatory and Anti-cancer Effect of sterol-rich Fraction from Nannochloropsis oculata by using Saponification

Junseong Kim,H. H. Chaminda Lakmal,Ji-Hyeok Lee,WonWoo Lee,You-Jin Jeon 한국식품영양과학회 2015 한국식품영양과학회 학술대회발표집 Vol.2015 No.8

ANTIOXIDANT AND IN VITRO ANTI-INFLAMMATORY ACTIVITIES OF THE SELECTED SRI LANKAN MARINE ALGAE

Kalpa W. Samarakoon,Chaminda Lakmal H. H.,D. T. U. Abeythunga,You J. Jeon 한국수산과학회 양식분과 2015 한국수산과학회 양식분과 학술대회 Vol.2015 No.5