22,872 research outputs found

    Interpretation of the characteristics of ocean-dumped sewage sludge related to remote sensing

    Get PDF
    Wastewater sludge characteristics in general, and characteristics of wastewater sludges generated by the City of Philadelphia in particular, were addressed. The types and sources of wastewater sludges, a description of sludge treatment and disposal processes, examination of sludge generation and management for the City of Philadelphia, and definition of characteristics for typical east coast sludges undergoing ocean disposal were discussed. Specific differences exist between the characteristics of primary and secondary wastewater sludges, especially with the nature and size distribution of the solids particles. The sludges from the City of Philadelphia monitored during remote sensing experiments were mixtures of various sludge types and lacked distinguishing characteristics. In particular, the anaerobic digestion process exerted the most significant influence on sludge characteristics for the City of Philadelphia. The sludges generated by the City of Philadelphia were found to be typical and harbor no unique features

    Criteria for the use of regression analysis for remote sensing of sediment and pollutants

    Get PDF
    Data analysis procedures for quantification of water quality parameters that are already identified and are known to exist within the water body are considered. The liner multiple-regression technique was examined as a procedure for defining and calibrating data analysis algorithms for such instruments as spectrometers and multispectral scanners

    Spin gap behavior in Cu2_2Sc2_2Ge4_4O13_{13} by 45^{45}Sc nuclear magnetic resonance

    Full text link
    We report the results of a 45^{45}Sc nuclear magnetic resonance (NMR) study on the quasi-one-dimensional compound Cu2_2Sc2_2Ge4_4O13_{13} at temperatures between 4 and 300 K. This material has been a subject of current interest due to indications of spin gap behavior. The temperature-dependent NMR shift exhibits a character of low-dimensional magnetism with a negative broad maximum at TmaxT_{max} ≃\simeq 170 K. Below % T_{max}, the NMR shifts and spin lattice relaxation rates clearly indicate activated responses, confirming the existence of a spin gap in Cu2_2Sc2_2Ge% 4_4O13_{13}. The experimental NMR data can be well fitted to the spin dimer model, yielding a spin gap value of about 275 K which is close to the 25 meV peak found in the inelastic neutron scattering measurement. A detailed analysis further points out that the nearly isolated dimer picture is proper for the understanding of spin gap nature in Cu2_2Sc2_2Ge4_4O13_{13}.Comment: 4 pages, 6 figures, submitted to Phys. Rev.

    Can manager's listening behavior benefit employees? Power distance may have the answer

    Get PDF
    The current research investigated employee’s perception of their manager’s listening behavior (MLB). Drawing on the group-value theory, we examined the role of MLB and analyzed its effect through employee’s power distance orientation. We distributed questionnaires to 219 employees and adopted two-wave data collection to ameliorate the bias of common method variance. Statistical analysis revealed that MLB was related to employees’ well-being and work engagement. For employees with lower power distance orientation, MLB led to more self-esteem. For employees with higher power distance orientation, MLB did not affect their self-esteem. MLB was not always beneficial to the employees, as individuals may interpret MLB positively or negatively. Research findings have brought new insights into the listening literature, particularly from the perspective of manager’s listening behavior. We encourage the organizations to incorporate listening skills into the education programs (for training incumbent managers) and recruitment criterions (for hiring new managers). Implications on the manager-employee relationship are also discussed

    Distance-two labelings of digraphs

    Full text link
    For positive integers j≥kj\ge k, an L(j,k)L(j,k)-labeling of a digraph DD is a function ff from V(D)V(D) into the set of nonnegative integers such that ∣f(x)−f(y)∣≥j|f(x)-f(y)|\ge j if xx is adjacent to yy in DD and ∣f(x)−f(y)∣≥k|f(x)-f(y)|\ge k if xx is of distant two to yy in DD. Elements of the image of ff are called labels. The L(j,k)L(j,k)-labeling problem is to determine the λ⃗j,k\vec{\lambda}_{j,k}-number λ⃗j,k(D)\vec{\lambda}_{j,k}(D) of a digraph DD, which is the minimum of the maximum label used in an L(j,k)L(j,k)-labeling of DD. This paper studies λ⃗j,k\vec{\lambda}_{j,k}- numbers of digraphs. In particular, we determine λ⃗j,k\vec{\lambda}_{j,k}- numbers of digraphs whose longest dipath is of length at most 2, and λ⃗j,k\vec{\lambda}_{j,k}-numbers of ditrees having dipaths of length 4. We also give bounds for λ⃗j,k\vec{\lambda}_{j,k}-numbers of bipartite digraphs whose longest dipath is of length 3. Finally, we present a linear-time algorithm for determining λ⃗j,1\vec{\lambda}_{j,1}-numbers of ditrees whose longest dipath is of length 3.Comment: 12 pages; presented in SIAM Coference on Discrete Mathematics, June 13-16, 2004, Loews Vanderbilt Plaza Hotel, Nashville, TN, US
    • …
    corecore