70,431 research outputs found
Determinants of Selected Agricultural Export Crops in Nigeria: An Ecm Approach
This study examines the factors that determine the export performance of three major agricultural exportable commodities of cocoa, rubber and palm-kernel in the context of liberalization. Using time series data covering thirty three years and to avoid spurious result, error correction model was applied in the analysis. The unit root test is in line with the a priori expectation that macroeconomic variables are not stationary at their level. Virtually all the variables tested were differenced once before attaining stationarity. Each of the three equations indicated that the dependent variables cointegrated with their arguments at 1 percent level. There is the existence of short term and long term equilibrium relationships between the dependent variables and their determinants. The results of the parsimonious error correction specifications showed that the previous year’s output and the net value of world trade negatively affect cocoa exports at 1 percent level while the previous year’s GDP positively contributes to cocoa exports at 5 percent. The lagged price ratio reduces rubber exports significantly at 5 percent but the real exchange rate significantly increases the export performance of rubber at 10 percent level. The previous year’s exports of palm kernel and the real GDP contributed positively to palm-kernel exports at 5 percent level while the lagged premium and palm kernel output negatively contributed to its export at 5 percent and 10 percent respectively. Promotion of agricultural exports is essential to reduce the burden of dependence on oil exportsAgricultural exports, Cointegration, ECM, Nigeria, Agricultural and Food Policy, Community/Rural/Urban Development, Crop Production/Industries, Demand and Price Analysis, Farm Management, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Industrial Organization, International Relations/Trade, Marketing, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies,
On-Chip Photonic Transistor based on the Spike Synchronization in Circuit QED
We consider the single photon transistor in coupled cavity system of
resonators interacting with multilevel superconducting artificial atom
simultaneously. Effective single mode transformation is used for the
diagonalization of the the hamiltonian and impedance matching in terms of the
normal modes. Storage and transmission of the incident field are described by
the interactions between the cavities controlling the atomic transitions of
lowest lying states. Rabi splitting of vacuum induced multiphoton transitions
is considered in input/output relations by the quadrature operators in the
absence of the input field. Second order coherence functions are employed to
investigate the photon blockade and localization-delocalization transitions of
cavity fields in oscillating regime of photon states described by the the
population imbalance. Refection and transmission of cavity output fields are
investigated in the presence of the multilevel transitions. Accumulation and
firing of the reflected and transmitted fields are used to investigate the
synchronization of the bunching spike train of transmitted field and population
imbalance of cavity fields. In the presence of single photon gate field, gain
enhancement is explained for transmitted regime.Comment: 8 pages,10 figure
Critical behavior and universality properties of uniaxial ferromagnetic thin films in the presence of random magnetic fields
Critical phenomena in uniaxial ferromagnetic thin films in the presence of
random magnetic fields have been studied within the framework of effective
field theory. When the type of the random field distribution is bimodal, the
system exhibits tricritical behavior. Furthermore, the critical value of
surface to bulk ratio of exchange interactions at which the transition
temperature becomes independent of film thickness is insensitive to the
presence of disorder whether the distribution is bimodal or trimodal. Regarding
the universality properties, neither , nor variations in the system can
affect the value of the shift exponent . In this regard, it can be
concluded that pure ferromagnetic thin films are in the same universality class
with those under the influence of random discrete magnetic fields.Comment: 19 pages, 13 figures. arXiv admin note: substantial text overlap with
arXiv:1304.725
KLASIFIKASI MALWARE ANDROID DENGAN MENGGUNAKAN METODE CATBOOST ALGORITMA
In 2008, Android was introduced as a popular open source project due to its customizability and low hardware requirements. Mid-2021 statistics from GlobalStat Counter shows that Android dominates the mobile operating system market with 72.74%. Despite its popularity, Android is becoming a target for malware attacks in the context of cyber crime. This problem prompted this research to be carried out with the aim of identifying and classifying Android malware which is continuously developing by applying machine learning logic, especially using the methodCatBoost. This method was chosen based on its effectiveness in previous research which has been proven to provide high accuracy. Performance evaluation involves comparisons betweenCatBoost and several previous researchers' methods, inclKNN (K-Nearest Neighbors), SVM (Support Vector Machine), LR (Logistic Regression), RF (Random Forest), ET (Extra Trees), XG (XGBoost), AB (Adaboost), and BG (Bagging), using common metrics such asValidation Accuracy, Detection Accuracy, and F1-Score. The research results show thatCatBoost managed to achieveValidation Accuracy amounting to 96.66%,Detection Accuracy 96,87%, andF1-Score of 96.81% puts it in a competitive position with most other methods, exceptRF (Random Forest). CatBoost's consistent superiority in this comparison shows its potential as an effective and consistent solution in Android malware detection and classification
Keeping an Open Mind: Challenges and Mysteries in Cancer Cell Biology Research
I received a Summer Undergraduate Research Fellowship (SURF) in 2016 to work in Professor Chuck Walker’s cell biology lab, where I had been involved since 2014. I worked under the guidance of Dr. Walker and alongside other colleagues in the lab. My work during that time focused on culturing cancer cells and investigatingthe proteinp53 within them. The body aims toprevent tumors from forming by protecting the integrity of its cells’ DNA. The protein p53 is so vital in this role that it is often referred to as the “guardian of the genome.” In fact, more than half of all human cancers are associated with malfunctionsthat disrupt p53 function. My project had two objectives. First, I sought to confirm the presence of the p53-mortalin complex in the cells I was planning to use. Second, I tried to disrupt the complex using MKT-077 and withanone and determine the effectiveness of these agents in allowing p53 to move to the nucleus and trigger apoptosis. I planned to designate groups of cells as untreated, MKT-treated, or withanone-treated. For each group, I chose a series of analytical techniques that could pinpoint p53 inthe cell (to see whether it was stuck in the cytoplasm or already in the nucleus) and determine the levels of cell death by apoptosis. The various surprises I experienced while working on my SURF project taught me that research won’t always be as clear-cut as one might expect. I learned the importance of keeping an open mind and considering the possibility of obstacles and unexpected outcomes in order to make sense of conflicting results
- …