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Value engineering (VE) has been credited with successfully improving the review of construction projects but it has not gained widespread acceptance in federal construction projects. This fact is due to several factors that resist the adoption of VE. These include the assumption that optimal designs are always pursued by design professionals, the reluctance of design professionals to subject their work to rigorous review, the desire to get on with business using traditional methods and pride or ego on the part of some design professionals.

Observant CPM schedulers in the early years of CPM application, the 1960s, noted that there were often familiar steps inherent in scheduling similar projects. This similarity occurred in the development of housing neighborhoods, such as New Town of Columbia, Maryland; schools, as in the Philadelphia School District Program involving 200 schools; and in the review process for projects during the preconstruction phase in large cities, namely Philadelphia and New York. In these situations, the development of a prototypical network provided a costeffective method of applying network scheduling to major programs. These applications are described in the form of case studies, and a recent application to the King Khalid Military City Housing Program is noted. An alternate manual approach to repetitive scheduling in highrise construction, the vertical production method developed in the 1970s, is also described.

We developed methods of forecasting cotton (Gossypium hirsutumL. var. hirsutum) yields at a county level 3 mo before harvest for the states of Alabama and Georgia. Cotton yield historical records for 57 counties were obtained from NASS and detrended using a low‐pass spectral filter. A Canonical Correlation Analysis regression‐based model was annually recalibrated to incorporate the year‐by‐year accumulating data: (i) April–June (during vegetative growth) observed rainfall for the forecasting year, and (ii) July–September (during reproductive growth) global‐scaled 2‐m mean temperatures for years before the forecasting year, beginning with 1970. We produced two types of forecasts: short range and medium range. The short‐range near‐term yield forecast (just before initiating harvest in the region) used gridded assimilated observed 2‐m mean temperatures obtained from the NCEP‐NCAR CDAS Reanalysis data. The medium‐range forecast (3 mo before harvest) used 2‐m mean temperature retrospective forecasts from the operational NOAA/NWS/NCEP Climate Forecasts System coupled global circulation model. The short‐range, near‐term forecast performance was measured by leave‐one‐out cross‐validation and retroactive validation, whereas medium‐range forecast performance used the previous two methods plus a proposed coral‐reef validation method. The agreement between short‐range near‐term forecast and actual cotton yield was statistically significant at the 0.05 level in 31 out of 57 counties. For 48% of these 31 counties, the agreements between medium‐range forecasts and actual cotton yields were statistically significant at the 0.05 level. The goodness‐of‐fit index for those 15 counties was 0.51 and the RMSE ranged from 13 to 31% of the annual yield.

Corrosion is the major factor in shortening the useful life of your boiler, especially the tubes. Tube leaks caused by corrosion are the most frequent reason for emergency boiler shutdowns. [...]

High-resolution intracavity laser spectroscopy (ILS) absorption measurements have been made on the b–Xoxygen electronic transition (the A-band) which has bandheads occurring in the region of 13 165 cm−1. The positions of the lines were determined to an accuracy that is based on calibration with I2absorption lines using the Laboratoire Aimé Cotton (Orsay) Atlas as reference. Based on the ILS measurements and the more accurately determined positions given by L. R. Brown and C. Plymate (J. Mol. Spectrosc.199, 166–179 (2000)) and with the 3Σg−ground state molecular constants fixed at the values determined by G. Rouillé et al.(J. Mol. Spectrosc.154, 372–382 (1992)), the following values (in cm−1) were found for the molecular constants: T0=13122.2524(1); B0=1.391244(2); D0=5.352(4)×10−6; and H0=−1.2(2)×10−11. These results are compared with values derived from fits of the line positions listed in several other studies of this transition.

High-resolution intracavity laser spectroscopy (ILS) absorption measurements have been made on the b - X oxygen electronic transition (the A-band) which has bandheads occurring in the region of 13 165 cm. The positions of the lines were determined to an accuracy that is based on calibration with I 2 absorption lines using the Laboratoire Aime´ Cotton (Orsay) Atlas as reference. Based on the ILS measurements and the more accurately determined positions given by L. R. Brown and C. Plymate ( J. Mol. Spectrosc. 199 , 166-179 (2000)) and with the Σ g ground state molecular constants fixed at the values determined by G. Rouille´ et al. ( J. Mol. Spectrosc. 154 , 372-382 (1992)), the following values (in cm) were found for the molecular constants: T 0 =13122.2524(1); B 0 =1.391244(2); D 0 =5.352(4)×10; and H 0 =−1.2(2)×10. These results are compared with values derived from fits of the line positions listed in several other studies of this transition.

The near-infrared electronic transition of CuCl, occurring in the region of 745 nm, was recorded using intracavity laser absorption spectroscopy. The (0, 0), (1, 1), and (2, 2) vibronic bands were analyzed, and from this the molecular constants for the two electronic states were derived. Originally assigned as A′ 3Σ+–X1Σ+, we have confirmed that this transition does not connect to the ground state, but occurs between two unknown excited states. The excited CuCl molecules were produced in a copper hollow cathode, operated using argon and a small amount of CCl4. Line positions were referenced to iodine spectra observed from a heated extracavity cell using the broadband spectral output of the intracavity laser as the light source.

The intracavity laser spectroscopy (ILS) technique has been shown to be a very sensitive method for observing absorption spectra. By considering quantitative results (line-strengths and pressure broadening coefficients) obtained using the ILS method with a dye laser, the technique has been shown to provide quantitative information that is in excellent agreement with the values afforded by use of more traditional methods for acquiring absorption spectra. A similar investigation has been conducted for an ILS system based on a Ti:sapphire laser. Presented here are quantitative results for water vapor transitions occurring around 795 nm. Line intensities are determined as a function of water vapor pressure and effective path length (i.e., generation time). The line-strengths are compared with values determined by R. A. Toth [J. Mol. Spectrosc.166, 176–183 (1994)] who used a multipass cell and the Fourier transform spectrometer at the Kitt Peak National Observatory. The good agreement between the results demonstrates that quantitatively accurate data can be obtained using the ILS technique with a Ti:sapphire laser.

The multi- and quasi-decadal variabilities of the sea surface temperature (SST) anomaly over the North Atlantic are investigated by means of two-dimensional propagating CEOF. Forty-six years of the COADS SST dataset from 1947 to 1992 are used. After removing the monthly climatology and four-year low-pass filtering the SST anomaly is submitted to CEOF. The total variance of the three largest modes accounts for 87.0 of the total variance.

AbstractInterannual and interdecadal variability of the equatorial Pacific are examined using a new pseudostress dataset. The monthly mean pseudostress fields (1930–89)are derived from Comprehensive Ocean-Atmosphere Data Set (COADS) pseudostresses using climate basis functions obtained from the Florida State University pseudostress product (1966–90). To validate the new wind fields, a two-tier validation scheme was used. The new wind fields were first examined to see if they exhibited characteristics that have been shown to be important in terms of exciting El Niño events. Next, the new wind fields are used to force an ocean model, thereby obtaining model estimates of tropical Pacific currents and model upper-layer thickness (ULT). Observed sea level and spatially averaged SST anomalies are used to validate the hindcasts. The new wind fields were found to have a significant El Niño mode (accounting for 41 of the variance), which possessed features consistent with those that theory and numerical simulations dictate. Interannual fluctuations in modeled and observed sea level fluctuations are compared at Galapagos and Truk, yielding correlation rvalues of 0.73 and 0.71, respectively. The comparison of the interannual fluctuations in modeled ULT and observed SST anomalies, which are both spatially averaged over a subdomain in the eastern Pacific basin, results in an rvalue of 0.64. Interdecadal fluctuations in eastern Pacific model ULT are found to be qualitatively consistent with those in the spatially averaged observed SST anomalies. Stronger El Niño events are observed to occur during periods of higher Pacific ULT (for decadal and longer timescales). Comparison of interdecadal fluctuations in global mean land air temperature and eastern Pacific ULT suggests a connection between eastern Pacific SST and tropical mean land air-temperature warming for interdecadal timescales.

MARCINIK, EDWARD J., JAMES A. HODGDON, KAREN MITTLEMAN, and JAMES J. O'BRIEN. Aerobic/calisthenic and aerobic/ circuit weight training programs for Navy men a comparative study. Med. Set. Sports Exerc., Vol. 17, No. 4, pp. 482-487,1985.

Methane spectral features in the visible to near-IR region are prominent in the spectra of the outer planets but laboratory data for the appropriate methane conditions are required to interpret the observational data. By use of the intracavity laser spectroscopy technique, a moderately high resolution (=500,000) absorption spectrum of the 727 nm band of methane at 77 K is obtained. The methane absorption bands in the visible to near-IR region are very weak, but intracavity laser spectroscopy provides sufficient sensitivity to perform the measurements and to extract quantitative data for methane at low temperatures. Absorption coefficients are determined and are reported as averages at one Å intervals throughout the region 7127–7420 Å. By integrating over the band, an intensity of 753 cm-1 km-1 am-1 is obtained. The results compare well with previous low resolution measurements on methane at room temperature, with gas phase results calculated using the absorption spectrum of liquid methane, and with absorption coefficients derived from methane features observed in the spectra of the outer planets and Titan.

The propagation of achromatic visible laser radiation through optical fibers is examined for a quasi-cw dye laser designed to record absorption by intracavity laser spectroscopy (ILS). The wavelength and intensity characteristics of the ILS laser output and any superimposed intracavity absorption features are preserved quantitatively for propagation through an extracavity single-mode optical fiber. Feedback from the front surface of the optical fiber and its associated optics can modify the ILS laser output. Two optical configurations which give no noticeable modifications to the ILS data propagated through the optical fiber are described. Applications of ILS for remote sensing, sensitive detection of extracavity feedback effects, and characterization of extracavity interferometric signals are indicated.

Intracavity laser absorption spectroscopy with ultrahigh sensitivity and enhanced spectral resolution is demonstrated. It entails use of an intracavity étalon that selects equally spaced modes of the cavity. These modes are reduced in intensity when they occur at spectral locations where absorption that is due to intracavity species also occurs. We obtained absorption spectra by tuning the étalon in small steps across its free spectral range, recording intracavity spectra at each step, and summing the result. The maximum resolution is determined by the width of the étalon peaks, which was ∼0.01 cm^-1. When the finesse of the étalon is increased, the resolution equal to the width of a single laser mode can be achieved. With this technique, spectra at Doppler-free resolution such as that required for studies of high vibrational-overtone transitions of molecules in supersonic jets are possible.

Two numerical models utilizing primitive equations (two momentum equations and a mass continuity equation) simulate the oceanography of the Pacific Ocean from 20°S to 50°N. Results show Kelvin waves thousands of kilometers long propagating from the equator to the northeast Pacific Ocean. Kelvin waves are very long waves that propagate along the equator and along solid boundaries with the boundary to their right. They are important to simulations of ocean circulation along the North American coast because they carry information at seasonal and longer periods from the equator poleward. Modeling an extensive region such as the Pacific Ocean with adequate two-dimensional resolution places heavy demands on computer memory and storage. We have found that the best way to examine the abundant model data is through visualization, by animating the appro priate model fields and viewing the time history of each model simulation as a color movie. The animations are used as research products to aid our understanding of ocean circulation. Several animations are reproduced in the accompanying video.

Complex empirical orthogonal function (CEOF) analysis is used to investigate the coastal Kelvin wave driven Rossby wave response in the northeast Pacific. Using CEOF analysis, a spatial structure function is obtained from model upper layer thickness data. The model is a nonlinear, reduced gravity model of the northeast Pacific forced by coastal Kelvin waves originating in the equatorial Pacific. The spatial structure function is used to extract the interannual Rossby wave response from observed 300-m-depth temperature anomalies. The observed Rossby wave signal is termed the projection mode. Rossby wavelike features observed in the projection mode are order 1000 km long with most periods ranging between 2 and 4 years. The wave numbers and frequencies found are consistent with Rossby dynamics. The mean phase speed of the Rossby wavelike features within the projection mode is 1.3 cm s-1, in agreement with the theoretical Rossby wave phase speed at 40°N. Large amplitude nearshore and decreasing amplitude away from shore suggests nearshore generation of these waves. An important source of sea level variability along the east coast of North America at periods of 2–4 years was identified by Pares-Sierra and O'Brien (1989) as poleward propagating Kelvin waves. Since the Rossby wavelike features observed in the projection mode have a majority of their periods ranging between 2 and 4 years, their forcing can be attributed to long-period Kelvin waves. Spectral comparisons between the nearshore values in the projection mode and coastal sea level show greater than 90% coherence in the period band 3–4.4 years. The high coherence between coastal sea level variations and the projection mode shows that there is a strong correlation between the Rossby wavelike features within the projection mode and coastal Kelvin wave propagation. It is concluded that the Rossby waves within the projection mode are forced by coastal Kelvin wave propagation. The projection mode accounts for 47.5% of the variance in the 300-m-depth temperature anomalies. The implication of this result is that the physical mechanism of the numerical model, i.e., Rossby waves excited by coastal Kelvin wave propagation, accounts for 47.5% of the variance in the observed 300-m depth temperature anomalies.

Since man first “came down from the trees” he has utilized geothermal resources. Hot springs have warmed his caves; the people of Rome, Greece, and Japan used hot springs for thermal and space heating. Today scientists seek ways to harness such sources for power—and to supply fresh water by desalting their brine.

AbstractA wind-driven model of coastal upwelling induced into a stratified, rotating ocean is solved numerically. The circulation is on an fplane and longshore variations are neglected. A multilevel model is derived, but only solutions for a two-layer model are discussed. A longshore baroclinic surface jet is discovered. The time-dependent geostrophic jet is dynamically explained by conservation of potential vorticity. The existence of the jet depends critically on stratification and non-zero wind stress at the coast. Coastal upwelling is confined to within 30 km of the shore. The model exhibits no deep countercurrent during active coastal upwelling. A time scale of the order of 10 days or longer is required for a pycnocline at 50 m depth to penetrate the surface. Solutions for a wide (>300 km) coastal shelf, an irregular shallow shelf, and a continental slope region are illustrated. A secondary upwelling region is found offshore at sharp breaks in the shelf topography. In all cases, the offshore flow is a simple Ekman drift and downwelling offshore is created by Ekman pumping caused by negative wind-stress curl.

This study investigates the characteristics of tides in the Gulf of Mexico (GoM) and the response to forcing by local tidal potential and tides propagating as waves through straits connecting this semienclosed sea to the Caribbean Sea and Atlantic Ocean. Numerical simulations performed with the Navy Coastal Ocean Model run in a barotropic configuration with 1/60° horizontal resolution are used to analyze the tidal response to different forcing mechanisms. The tidal energy budget and tidal energy fluxes in the GoM are calculated from the simulations. Results show that diurnal tides in the GoM are dominantly due to co‐oscillation with the western Atlantic and that a substantial amount of semidiurnal tidal energy also enters the Gulf through the straits. Model experiments suggest that adding the local tidal potential significantly modifies the propagation of the semidiurnal tidal signal within the GoM and reduces the tidal power associated with the diurnal tides in the basin. An interesting phenomenon of nonlinear interaction between the two forcing mechanisms (local forcing and propagation through the straits) is described and explained by using a mechanistic mass‐spring system model.