Estimating Production Functions with R&D Investment and Endogeneity

This study analyses the production function estimation when there is an unobservable idiosyncratic productivity shock and the series of the productivity shock follows a first-order endogenous Markov process which is controlled by R&D investment. The production function approach, in general, suffers from endogeneity problems when there are determinants of production which are not observed by the econometrician but are observed by the manager of a firm. To control for this problem, recently developed econometric methods are applied to the production function estimation. The results show that there is a possibility that other estimation methods such as OLS estimation and fixed effect estimation underestimates the contribution of capital. The results also suggest that the rate of return to R&D varies considerably across industries and within an industry.

An Authentication Protocol for Future Sensor Networks

Authentication is one of the essential security services in Wireless Sensor Networks (WSNs) for ensuring secure data sessions. Sensor node authentication ensures the confidentiality and validity of data collected by the sensor node, whereas user authentication guarantees that only legitimate users can access the sensor data. In a mobile WSN, sensor and user nodes move across the network and exchange data with multiple nodes, thus experiencing the authentication process multiple times. The integration of WSNs with Internet of Things (IoT) brings forth a new kind of WSN architecture along with stricter security requirements; for instance, a sensor node or a user node may need to establish multiple concurrent secure data sessions. With concurrent data sessions, the frequency of the re-authentication process increases in proportion to the number of concurrent connections, which makes the security issue even more challenging. The currently available authentication protocols were designed for the autonomous WSN and do not account for the above requirements. In this paper, we present a novel, lightweight and efficient key exchange and authentication protocol suite called the Secure Mobile Sensor Network (SMSN) Authentication Protocol. In the SMSN a mobile node goes through an initial authentication procedure and receives a re-authentication ticket from the base station. Later a mobile node can use this re-authentication ticket when establishing multiple data exchange sessions and/or when moving across the network. This scheme reduces the communication and computational complexity of the authentication process. We proved the strength of our protocol with rigorous security analysis and simulated the SMSN and previously proposed schemes in an automated protocol verifier tool. Finally, we compared the computational complexity and communication cost against well-known authentication protocols.Comment: This article is accepted for the publication in "Sensors" journal. 29 pages, 15 figure

Effective Caching for the Secure Content Distribution in Information-Centric Networking

The secure distribution of protected content requires consumer authentication and involves the conventional method of end-to-end encryption. However, in information-centric networking (ICN) the end-to-end encryption makes the content caching ineffective since encrypted content stored in a cache is useless for any consumer except those who know the encryption key. For effective caching of encrypted content in ICN, we propose a novel scheme, called the Secure Distribution of Protected Content (SDPC). SDPC ensures that only authenticated consumers can access the content. The SDPC is a lightweight authentication and key distribution protocol; it allows consumer nodes to verify the originality of the published article by using a symmetric key encryption. The security of the SDPC was proved with BAN logic and Scyther tool verification.Comment: 7 pages, 9 figures, 2018 IEEE 87th Vehicular Technology Conference (VTC Spring

Karakter Fisiologis dan Kemangkusan Rizobakteri Indigenus Sulawesi Tenggara sebagai Pemacu Pertumbuhan Tanaman Cabai

Sejumlah besar mikroorganisme yang terdapat pada rizosfer tanaman diketahui berperan penting dalam pertanianberkelanjutan karena potensinya sebagai agens pengendali hayati dan pemacu pertumbuhan tanaman. Percobaan bertujuanmengevaluasi kemampuan isolat rizobakteri indigenus Sulawesi Tenggara yang dieksplorasi dari Kabupaten Konawe, Konawe Selatan,Kendari, Muna, dan Buton dalam memproduksi hormon tumbuh indole acetic acid (IAA) dan melarutkan fosfat. Evaluasi jugadilakukan untuk mengetahui kemangkusan isolat rizobakteri sebagai pemacu pertumbuhan tanaman cabai. Penelitian dilaksanakandi Laboratorium Agronomi dan Kebun Percobaan Fakultas Pertanian, Universitas Haluoleo Kendari, Sulawesi Tanggara, daribulan April sampai dengan Oktober 2009. Hasil percobaan menunjukkan bahwa isolat rizobakteri yang diuji memiliki kemampuanyang berbeda dalam mensintesis IAA . Rizobakteri dari kelompok Bacillus spp. memiliki kemampuan menghasilkan IAA dengankonsentrasi lebih tinggi (5,32–146,97 μg/ml) dibandingkan dengan Pseudomas fluorescens C179, (0,78 μg/ml), sementara Serratiasp. C175 tidak dapat mensintesis IAA. Di lain pihak, semua isolat rizobakteri yang diuji mampu melarutkan fosfat. Sementara itu,hasil pengaruh perlakuan benih dengan rizobakteri menunjukkan bahwa dari 10 isolat yang diuji, hanya isolat Bacillus spp. C061, P.fluorescens C179, dan Serratia sp.C175 yang konsisten memberikan efek yang lebih baik terhadap viabilitas benih dan pertumbuhanbibit cabai dibandingkan dengan kontrol dan isolat uji lainnya. Oleh karena itu isolat Bacillus spp. C061, P. fluorescens C179, danSerratia sp. C175 dapat direkomendasikan sebagai agens pemacu pertumbuhan cabai

Plant Turnover and TFP Dynamics in Japanese Manufacturing

This study analyzes the cause of the slowdown in Japan's TFP growth during the 1990s. Many preceding studies, examining the issue at the macro- or industry-level, have found that the slowdown was primarily due to the stagnation in TFP growth in the manufacturing sector. Using establishment level panel data covering the entire sector, we investigate the causes of the TFP slowdown and find that the reallocation of resources from less efficient to more efficient firms was very slow and limited. This "low metabolism" seems to be an important reason for the slowdown in Japan's TFP growth.