A Review on Air Quality Indexing System

Kanchan,Amit Kumar Gorai,Pramila Goyal 한국대기환경학회 2015 Asian Journal of Atmospheric Environment (AJAE) Vol.9 No.2

Air quality index (AQI) or air pollution index (API) is commonly used to report the level of severity of air pollution to public. A number of methods were developed in the past by various researchers/environmental agencies for determination of AQI or API but there is no universally accepted method exists, which is appropriate for all situations. Different method uses different aggregation function in calculating AQI or API and also considers different types and numbers of pollutants. The intended uses of AQI or API are to identify the poor air quality zones and public reporting for severity of exposure of poor air quality. Most of the AQI or API indices can be broadly classify as single pollutant index or multi-pollutant index with different aggregation method. Every indexing method has its own characteristic strengths and weaknesses that affect its suitability for particular applications. This paper attempt to present a review of all the major air quality indices developed worldwide.

A Review on Air Quality Indexing System

Kanchan, Kanchan,Gorai, Amit Kumar,Goyal, Pramila Korean Society for Atmospheric Environment 2015 Asian Journal of Atmospheric Environment (AJAE) Vol.9 No.2

Air quality index (AQI) or air pollution index (API) is commonly used to report the level of severity of air pollution to public. A number of methods were developed in the past by various researchers/environmental agencies for determination of AQI or API but there is no universally accepted method exists, which is appropriate for all situations. Different method uses different aggregation function in calculating AQI or API and also considers different types and numbers of pollutants. The intended uses of AQI or API are to identify the poor air quality zones and public reporting for severity of exposure of poor air quality. Most of the AQI or API indices can be broadly classify as single pollutant index or multi-pollutant index with different aggregation method. Every indexing method has its own characteristic strengths and weaknesses that affect its suitability for particular applications. This paper attempt to present a review of all the major air quality indices developed worldwide.

The Performance of Multistage Cooperation in Relay Networks

Kanchan Vardhe,Daryl Reynolds 한국통신학회 2015 Journal of communications and networks Vol.17 No.5

We analyze the performance of multistage cooperation in decode-and-forward relay networks where the transmission between source and destination takes place in T ≥ 2 equal duration and orthogonal time phases with the help of relays. The source transmits only in the first time phase. All relays that can decode the source’s transmission forward the source’s message to the destination in the second time phase, using a space-time code. During subsequent time phases, the relays that have successfully decoded the source message using information from all previous transmitting relays, transmit the space-time coded symbols for the source’s message. The non-decoding relays keep accumulating information and transmit in the later stages when they are able to decode. This process continues for T cooperation phases. We develop and analyze the outage probability of multistage cooperation protocol under orthogonal relaying. Through analytical results, we obtain the near-optimal placement strategy for relays that gives the best performance when compared with most other candidate relay location strategies of interest. For different relay network topologies, we also investigate an interesting tradeoff between an increased SNR and decreased spectral efficiency as the number of cooperation stages is increased. It is also shown that the largest multistage cooperation gain is obtained in the low and moderate SNR regime.

Prediction of greenhouse gas emission from municipal solid waste for South Korea

Kanchan Popli,Jeejae Lim,Hyeon Kyeong Kim,Young Min Kim,Nguyen Thanh Tuu,Seungdo Kim 대한환경공학회 2020 Environmental Engineering Research Vol.25 No.4

This study is proposing a System Dynamics Model for estimating Greenhouse Gas (GHG) emission from treating Municipal Solid Waste (MSW) in South Korea for years 2000 to 2030. The government of country decided to decrease the total GHG emission from waste sector in 2030 as per Business-as-usual level. In context, four scenarios are generated to predict GHG emission from treating the MSW with three processes i.e., landfill, incineration and recycling. For prior step, MSW generation rate is projected for present and future case using population and waste generation per capita data. It is found that population and total MSW are directly correlated. The total population will increase to 56.27 million and total MSW will be 21.59 million tons in 2030. The methods for estimating GHG emission from landfill, incineration and recycling are adopted from IPCC, 2006 guidelines. The study indicates that Scenario 2 is best to adopt for decreasing the total GHG emission in future where recycling waste is increased to 75% and landfill waste is decreased to 7.6%. Lastly, it is concluded that choosing proper method for treating the MSW in country can result into savings of GHG emission.

Disaster Assessment and Mitigation Planning

Kanchan Das,R. S. Lashkari,N. Biswas 대한산업공학회 2013 Industrial Engineeering & Management Systems Vol.12 No.4

This paper proposes a mathematical modeling-based approach for assessing disaster effects and selecting suitable mitigation alternatives to provide humanitarian relief (HR) supplies, shelter, rescue services, and long-term services after a disaster event. Mitigation steps, such as arrangement of shelter and providing HR items (food, water, medicine, etc.) are the immediate requirements after a disaster. Since governments and non-governmental organizations (NGOs) providing humanitarian aid need to know the requirements of relief supplies and resources for collecting relief supplies, organizing and initiating mitigation steps, a quick assessment of the requirements is the precondition for effective disaster management. Based on satellite images from weather forecasting channels, an area/dimension of the disaster-affected zones and the extent of the overall damage may often be obtained. The proposed approach then estimates the requirements for HR supplies, supporting resources, and rescue services using the census and other government data. It then determines reliable transportation routes, optimum collection and distribution centers, alternatives for resource support, rescue services, and long-term help needed for the disaster-affected zones. A numerical example illustrates the applicability of the model in disaster mitigation planning.

Integrating Machine Reliability and Preventive Maintenance Planning in Manufacturing Cell Design

Kanchan Das,R.S. Lashkari,S. Sengupta 대한산업공학회 2008 Industrial Engineeering & Management Systems Vol.7 No.2

This paper presents a model for designing cellular manufacturing systems (CMS) by integrating system cost, machine reliability, and preventive maintenance (PM) planning. In a CMS, a part is processed using alternative process routes, each consisting of a sequence of visits to machines. Thus, a level of ‘system reliability’ is associated with the machines along the process route assigned to a part type. Assuming machine reliabilities to follow the Weibull distribution, the model assigns the machines to cells, and selects, for each part type, a process route which maximizes the overall system reliability and minimizes the total costs of manufacturing operations, machine underutilization, and inter-cell material handling. The model also incorporates a reliability based PM plan and an algorithm to implement the plan. The algorithm determines effective PM intervals for the CMS machines based on a group maintenance policy and thus minimizes the maintenance costs subject to acceptable machine reliability thresholds. The model is a large mixed integer linear program, and is solved using LINGO. The results point out that integrating PM in the CMS design improves the overall system reliability markedly, and reduces the total costs significantly.

Heterogenous Gate Dielectric DLTFET: Reliability Perspective Against Degradation Mechanisms

Kanchan Cecil,Meena Panchore,Dip Prakash Samajdar 한국전기전자재료학회 2022 Transactions on Electrical and Electronic Material Vol.23 No.5

Heterogeneous gate dielectric (HD) dopingless n-type tunnel-FET (HD-DLTFET) is proposed with improved reliability performance against distinct drain current degradation mechanisms. Using calibrated 2-D TCAD device simulations, a comparative reliability analysis has been performed between proposed HD-DLTFET and conventional DLTFET, which shows only 14.2% drain degradation in HD-DLTFET against 41.9% in conventional DLTFET under hot-carrier stress conditions. On the other hand, simulation results confirmed that the drain current degradation mainly occurred due to the presence of interface-trap and/or oxide charges above the tunneling region, which reduced the tunneling field and tunneling current. Precisely, the interface traps induce the transconductance degradation, while, the oxide charges cause a threshold-voltage shift in conventional DLTFET, whereas, HD-DLTFET show negligible degradation under the influence of both interfacetrap and oxide-charges. Hence, HD-DLTFET accomplishes an impressive I ON / I OFF current ratio of 10 13 and 1.6 × reduced average subthreshold swing as compared to conventional DLTFET.

Experiencing Homelessness

Kanchan Gandhi 부산대학교 한국민족문화연구소 2015 Localities Vol.5 No.-

UN RINGS AND GROUP RINGS

Kanchan, Jangra,Dinesh, Udar Korean Mathematical Society 2023 대한수학회보 Vol.60 No.1

A ring R is called a UN ring if every non unit of it can be written as product of a unit and a nilpotent element. We obtain results about lifting of conjugate idempotents and unit regular elements modulo an ideal I of a UN ring R. Matrix rings over UN rings are discussed and it is obtained that for a commutative ring R, a matrix ring M_n(R) is UN if and only if R is UN. Lastly, UN group rings are investigated and we obtain the conditions on a group G and a field K for the group algebra KG to be UN. Then we extend the results obtained for KG to the group ring RG over a ring R (which may not necessarily be a field).

EGF, a veteran of wound healing: highlights on its mode of action, clinical applications with focus on wound treatment, and recent drug delivery strategies

Kanchan Shakhakarmi,Jo-Eun Seo,Shrawani Lamichhane,Chhitij Thapa,Sangkil Lee 대한약학회 2023 Archives of Pharmacal Research Vol.46 No.4

Epidermal growth factor (EGF) has been used in wound management and regenerative medicine since the late 1980s. It has been widely utilized for a long time and still is because of its excellent tolerability and efficacy. EGF has many applications in tissue engineering, cancer therapy, lung diseases, gastric ulcers, and wound healing. Nevertheless, its in vivo and during storage stability is a primary concern. This review focuses on the topical use of EGF, especially in chronic wound healing, the emerging use of biomaterials to deliver it, and future research possibilities. To successfully deliver EGF to wounds, a delivery system that is proteolytically resistant and stable over the long term is required. Biomaterials are an area of interest for the development of such systems. These systems may be used in non-healing wounds such as diabetic foot ulcers, pressure ulcers, and burns. In these pathologies, EGF can reduce the risk of amputation of the lower extremities, as it accelerates the wound healing process. Furthermore, appropriate delivery system would also stabilize and control the EGF release profile in a wound. Several in vitro and in vivo studies have already proven the efficacy of such systems in the above-mentioned types of wounds. Moreover, several formulations such as ointments and intralesional injections are already available on the market. However, these products are still problematic in terms of inadequate diffusion of EGF, low bioavailability storage conditions, and shelf-life. This review discusses the nano formulations comprising biomaterials infused with EGF which could be a promising delivery system for chronic wound healing in the future.