DSpace at IIT Bombay
http://dspace.library.iitb.ac.in:80/jspui
The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.Fri, 28 Nov 2014 06:01:26 GMT2014-11-28T06:01:26ZD- and MS-optimal 2-Level Choice Designs for $N\not\equiv 0$ (mod 4)
http://dspace.library.iitb.ac.in/jspui/handle/100/16234
Title: D- and MS-optimal 2-Level Choice Designs for $N\not\equiv 0$ (mod 4)
Authors: Singh, Rakhi; Chai, Feng-Shun; Das, Ashish
Abstract: Street and Burgess (2007) present a comprehensive exposition of designs for choice experiments till then. Our focus is on choice experiments with two-level factors and a main effects model. We consider designs for choice experiment involving $k$ attributes (factors) and all choice sets are of size $m$. We derive a simple form of the Information matrix of a choice design for estimating the factorial effects. For $N$ being the number of choice sets in the design, we obtain $D$- and $MS$-optimal designs in the class of all designs with given $N$, $k$ and $m=2$. For given $N$ and $k$, we show that in many situations $D$-optimal designs for $m=2$ are superior than the optimal design for $m=3$ and $m=5$. Also, $MS$-optimal designs with $m=2$ are always better than the best designs under the same optimality criteria for any odd $m$. Furthermore, with respect to $trace$-optimality, there is no optimal design for $m>2$ which is better than the optimal design for $m=2$.Sat, 22 Nov 2014 00:00:00 GMThttp://dspace.library.iitb.ac.in/jspui/handle/100/162342014-11-22T00:00:00ZCharacterization and Optimal Designs for Choice Experiments
http://dspace.library.iitb.ac.in/jspui/handle/100/16233
Title: Characterization and Optimal Designs for Choice Experiments
Authors: CHAI, FENG-SHUN; DAS, ASHISH; MANNA, SOUMEN
Abstract: Street and Burgess (2007) present a comprehensive exposition of designs for choice experiments till then. The choice design involves $n$ attributes (factors) with $i$-th attribute at $l_i$ level, and all choice sets are of size $m$. A choice design comprises $N$ such choice sets. Recently, Demirkale, Donovan and Street (2013) considered the setup of symmetric factorials ($l_i=l$) and obtained $D$-optimal choice designs under main effects model. They provide some sufficient conditions for a designs to be $D$-optimal. In this paper, we first derive a slightly modified Information matrix of a choice design for estimating the factorial effects of a $l_1 \times l_2 \times \cdots \times l_n$ choice experiment. It is seen that such a modification gives the Information matrix the desired additive property and thus, overcomes the existing shortcoming of situations where, with addition of a choice set the information content of the design decreases. While comparing designs with different $N$, we see that one needs to work with the modified information matrix. For a $2^n$ choice experiment, under the main effects model, we give a simple necessary and sufficient condition for the Information matrix to be diagonal. Furthermore, we characterize the structure of the choice sets which gives maximum $trace$ of the Information matrix. Our characterization of such an Information matrix facilitates construction of universally optimal designs with minimal number of choice sets and gives more flexibility for choosing $m$. Finally, we provide universally optimal choice designs for estimating main effects, which are optimal in the class of all designs with given $N$, $n$ and $m$.Fri, 21 Nov 2014 00:00:00 GMThttp://dspace.library.iitb.ac.in/jspui/handle/100/162332014-11-21T00:00:00ZA Myth called ‘Any Branch Banking’ - Service Charge Discrimination : Misrepresentation of Monetary Policy Regulatory Stance
http://dspace.library.iitb.ac.in/jspui/handle/100/16232
Title: A Myth called ‘Any Branch Banking’ - Service Charge Discrimination : Misrepresentation of Monetary Policy Regulatory Stance
Authors: Das, Ashish
Abstract: The term “Inter-sol charges” has been used frequently by banks and off late by Reserve Bank of India (RBI). The word ‘sol’ means branch. Thus intersol charges mean inter-branch charges. These are charges levied by banks for using service of branches other than the home branch where a customer originally opened his account. With prevalence of core banking solution (CBS), when a customer opens an account at a bank branch, he becomes a customer of the bank and not of the branch. In the CBS environment, the account resides in a central server at a location different from where it is opened. Though it is superficially ‘tagged’ to the parent or home branch it can be operated from any branch of the bank with equal ease. In fact, if CBS is not functioning, no transaction can be carried out in the account either in the parent branch or any other branch. This is the concept of ‘Any Branch Banking’. However, banks on lines similar to toll imposed on newly constructed bridges / roads, devised means to charge toll by interpreting intersol charges as charges for using CBS to get a service at a non-home branch, thereby attempting to rationally differentiate charges at home and non-home locations for a banking service. Incidentally, banks never reasoned (and rightly so) intersol charges as attributable to handling charges– be it, non-home cash handling; non-home cheque handling; non-home passbook handling; non-home customer handling, etc.
RBI through its July 1, 2013 notification directed banks not to impose any intersol charges (or toll). However, the same notification suggested that banks can impose a peculiar toll in the name of cash handling charge (when customers deposit cash into or withdraw cash out of their bank accounts, even if amount involved is small) at a non-home branch while equivalent charges do not exist at the home branch. Getting a cue from the notification, State Bank of India now charges their customers Rs. 50 for every non-home cash deposit, even when the deposit amount is small (say, in the range of Rs. 10 to Rs. 1000). Thus the RBI notification has induced banks to introduce intersol charges for cash handling, discriminating home and non-home charges, in breach of the spirit of its own Monetary Policy Statement of May 3, 2013. Though there is nothing wrong with the concept of cash handling charges, such a notion exists for bulk cash handling and not for small amount cash. Furthermore, a differentiation between home / non-home is implicitly intersol differentiation. In other words, imposition of cash handling charges makes sense so long as the charges are reasonable and that such a charge is made reasonably uniform across home and non-home branches. The action points to address these and related issues are as under.Sun, 26 Oct 2014 00:00:00 GMThttp://dspace.library.iitb.ac.in/jspui/handle/100/162322014-10-26T00:00:00ZPre-metallization processes for c-Si solar cells
http://dspace.library.iitb.ac.in/jspui/handle/100/16231
Title: Pre-metallization processes for c-Si solar cells
Authors: AAKELLA, PS; SARAVANAN, S; JOSHI, SS; SOLANKI, CS
Abstract: Crystalline silicon photovoltaic (PV) technology dominates 85% of the PV share due to its ease process and manufacturing flow. Conventional silicon PV technology uses screen printing for the metallization and though most of the PV industries use this technique, it has its own limitations for fabricating solar cells of high efficiency beyond 19%. However this technique is widely used in industries as a major process because of its production feasibility and cost compared to the alternate metallization techniques. In this article, an attempt has been made to study the different printing mechanisms, alternate to screen printing technique. Also, the process and results of alternate printing mechanisms were interpreted and compared with screen printing technique. It is well understood that the PV industries looking for the cost effective advanced metallization technique for fabricating high efficiency solar cells. (C) 2013 Elsevier Ltd. All rights reserved.Tue, 01 Jan 2013 00:00:00 GMThttp://dspace.library.iitb.ac.in/jspui/handle/100/162312013-01-01T00:00:00Z