The Effects of Knowledge Capital on Enhancing Firms’Productivity in Taiwan : Does R&D or Technology Import Matter?

R&D, technology imports, productivity, spillover

Dynamic Interrelation of Births and Deaths: Evidence from Plant Level Data

In this paper, the dynamic panel data method is used to investigate the dynamic interrelation of plant births and plant deaths. The dynamic panel data method considers the endogenous problem and individual effects. Empirical findings support the multiplier effect. In addition, exit does not cause entry, whereas entry causes exit.

PRODUCTIVITY SPILLOVERS IN INDIAN MANUFACTURING FIRMS

Indian economic reform since early 1990s aims at improving productivity and competitiveness of major industries. The paper examines spillovers from foreign direct investment (FDI), research and development (R&D) and exporting activities on productivity both for foreign and domestic manufacturing firms. The data is obtained from the PROWESS database provided by the Centre for Monitoring Indian Economy (CMIE). Balanced panel of over 1,000 manufacturing firms in India between 1994 and 2006 are considered for our empirical analysis. Findings indicate that foreign presence has a significant spillover effect on the productivity of the Indian manufacturing firms compared to the alternative spillovers such as from R&D and export initiatives.Productivity, Spillovers, Indian manufacturing, FDI.

Performance of Energy Efficient Relaying for Cluster-Based Wireless Sensor Networks

This paper proposes a novel energy efficient data relaying scheme to improve energy efficiency for cluster-based wireless sensor networks (WSNs). In order to reduce the energy dissipation of transmitting sensing data at each sensor, the fixed clustering algorithm uniformly divides the sensing area into clusters where the cluster head is deployed to the centered of the cluster area. Moreover, to perform energy efficient data relaying fixed clustering (EERFC), the cluster head is deployed as close to the sink as possible. Simulation results show that proposed EERFC definitely reduces the energy consumption of the sensors and it can further efficiently relay the cluster data

Polythiophenes comprising conjugated pendantstoward long-term air-stable inverted polymer solar cellswith high open circuit voltages

A series of polythiophenes (PTs) functionalized with bulky conjugated side chains comprising tert-butylsubstituted carbazole (tCz) as an electron donor pendant and bisbenzothiazolylvinyl (DBT) as anelectron acceptor pendant were synthesized via Stille copolymerization for polymer solar cell (PSC)applications. We use the descriptors PTtCz, PT(tCz)0.9(DBT)0.1, PT(tCz)0.64(DBT)0.36, PT(tCz)0.45(DBT)0.55,and PTDBT to identify each of these conjugated polymers, with the names denoting the compositionsof the bulky pendants. The tunable energy levels of the PTs were accomplished by incorporating bothtCz as a donor pendant and DBT as an acceptor pendant, while retaining the low-lying HOMO levels( 5.26 to 5.39 eV). Furthermore, lower bandgaps were observed for the DBT-derived PTs because ofstronger donor–p–acceptor characteristics and more efficient intramolecular charge transfer.Conventional PSCs were fabricated by spin-coating the blend of each PT and the fullerene derivative(PC71BM). The conventional PSC devices exhibited high open circuit voltages (Voc) of around 0.79–0.91 V. The power conversion efficiency (PCE) of the PSCs based on PTtCz : PC71BM (w/w ¼ 1 : 2.5)reached 2.48% with a Voc of 0.91 V, short circuit current (Jsc) of 6.58 (mA cm 2) and fill factor (FF) of41% under the illumination of AM1.5, 100 mW cm 2. Furthermore, a PTtCz/PC71BM-based inverted PSCwith ZnOx and MoO3 as an electron extraction layer and a hole extraction layer respectively was capableof retaining ca. 80% of its original efficiency after storage under ambient conditions (withoutencapsulation) for 1032 h, according to the ISOS-D-1 shelf protocol. The highly durable inverted PSCaccompanied by a large Voc value was achieved for the PT-type polymers

Novel polythiophene derivatives functionalized withconjugated side-chain pendants comprisingtriphenylamine/carbazole moieties for photovoltaic cellapplications†

We synthesized a series of polythiophenes (PTs) featuring 2-ethylhexyl-substituted terthiophene (T) orquaterthiophene (BT) as the conjugated unit in the polymer backbone with pendant conjugated tertbutyl-substituted triphenylamine (tTPA)- or carbazole (tCz)-containing moieties as side chains, namelyPTtTPA, PBTtTPA, PTtCz and PBTtCz. Incorporating T and BT moieties into the polymer backbone andattaching tTPA or tCz units promoted efficient conjugation within the extended conjugated frameworksof the polymers, resulting in lower band-gap energies and red-shifting of the maximal UV-Visabsorption wavelength. The higher electron-donating ability of tTPA resulted in broader absorptionbands and lower band-gap energies of PTtTPA and PBTtTPA as compared with PTtCz and PBTtCz.Incorporation of the T and BT moieties into the polymer backbone enhanced the compatibility of PTand the fullerene derivative by reducing the side-chain density of PT, thus providing sufficient freevolume for efficient incorporation of [6,6]phenyl-C61-butyric acid methyl ester (PC61BM) into thepolymer chains. Polymer solar cells (PSCs) were fabricated by spin-coating a blend of each PT with thefullerene derivative (PC61BM) as a composite film-type photoactive layer; PBTtTPA/PC61BM-based PSCsshowed superior photovoltaic (PV) performance to PTtTPA/PC61BM-based PSCs in terms of conjugationand absorption band broadness. However, PBTtCz/PC61BM-based PSCs showed inferior PV performanceto PTtCz/PC61BM-based PSCs. The lower HOMO level led to a higher open-circuit voltage (Voc; 0.74 V)and larger photo-energy conversion efficiency (h; 2.77%) of PTtCz/PC61BM-based PSCs

A dynamic model of auctions with buy-it-now: theory and evidence

In the ascending-price auctions with Yahoo!-type buy-it-now (BIN), we characterize and derive the closed-form solution for the optimal bidding strategy of the bidder and the optimal BIN price of the seller when they are both risk-averse. The seller is shown to be strictly better o with the BIN option, while the bidders are better o only when their valuation is greater than a threshold value. The theory also implies that the expected transaction price is higher in an auction with an optimal BIN price than one without a BIN. This prediction is conrmed by our data collected from Taiwan's Yahoo! auctions of Nikon digital cameras

A dynamic model of auctions with buy-it-now: theory and evidence

In the ascending-price auctions with Yahoo!-type buy-it-now (BIN), we characterize and derive the closed-form solution for the optimal bidding strategy of the bidder and the optimal BIN price of the seller when they are both risk-averse. The seller is shown to be strictly better o with the BIN option, while the bidders are better o only when their valuation is greater than a threshold value. The theory also implies that the expected transaction price is higher in an auction with an optimal BIN price than one without a BIN. This prediction is conrmed by our data collected from Taiwan's Yahoo! auctions of Nikon digital cameras