LTC2: Only a first step in the right direction†

In a recent issue of this journal, Mitra et al. (1983) introduced a new heuristic LTC2 for lot size planning under time-varying demand. LTC2 is based on the least-total-cost (LTC) method, which tries to balance set-up costs against holding costs. LTC2 can be interpreted as applying the Silver-Meal (1973) heuristic in the first two periods of a procurement cycle only, and applying a certain LTC version in all other cases. This paper argues that the Silver-Meal heuristic usually performs better than the conventional LTC versions and that, on average nothing can be gained by combining the LTC and Silver-Meal procedures. In this sense, LTC2 is only a first step in the right direction: away from an inefficient LTC procedure.     

基于Modelica的生物质燃气内燃机性能模拟研究

针对由沼气成分及其理化特性导致的内燃机燃用沼气时会发生燃烧速度慢、后燃严重、排气温度高等问题,将生物质燃气内燃机作为研究对象,基于可重用性及面向对象的Modelica语言建立内燃机模型库,将生物质燃气为燃料对四缸四冲程火花点火内燃机性能进行分析.通过仿真研究不同比例天然气(体积分数分别为33%,67%及100%)和LP...     

Application of Chrome Dyes to Wool by the Afterchrome Process

The fundamentals of and practical experience with a new method of applying chrome dyes to wool by the after–chrome process are discussed. The method is based on the stoichiometric relation between chromium and chrome dyes. By using special temperature control and an electrolyte, potassium dichromate is utilized more efficiently and effluent requirements can be met in most cases. The quality of the wool is improved compared to wool dyed by conventional afterchrome processes.     

QUANTUM CYBERNETICS: SYSTEMIC MODELING VERSUS MAGICAL MYSTIFICATIONS OF QUANTUM THEORY

Despite all negative accounts in many popular and superficial discussions of quantum theory causal and realistic interpretations of the quantum me chanical formalism can be demonstrated to work perfectly well They accept nonlocality as a well established fact and mostly consider a quantum system as analyzable into a local particlelike nonlinearity of a generally nonlocal wavelike mode of some subquantum structure of the vacuum Dirac ether In this view a particle can be considered as being guided along one specific route by the generally nonlocal configurations of superimposed waves which spread along all possible paths of an experimental setup Moreover in the approach of quantum cybernetics an additional focus is on the fact that the energy and momentum of a particle also determine the wave behavior Thus waves and particles are mutually and self consistently defined and quantum cybernetics puts particular emphasis on the circular relationship mediated byplane waves between a quantum system and its macroscopically defined boundary conditions To show how firmly rooted this picture is in the orthodoxquantum theory an example is discussed here on the basis of the standard formalism that makes a systemic approach called for     

Four years of ocean colour remote sensing with MOS-IRS

The imaging spectrometer MOS on IRS-P3 was launched in March 1996 as the first example of a new generation of ocean colour sensors. It consists of three different spectrometers in the visible/near-infrared spectral region with 18 channels. The IRS-P3 mission is focused on the remote sensing of case 2 water, particularly the derivation of different water constituents in coastal waters. Due to the more complex spectral behaviour of case 2 water, a new methodological approach was developed which works directly with satellite measured top-of-atmosphere radiance and accounts for the correlation of the different water constituents as well as for the spectral shape.

This paper gives an overview of the mission, the scientific goals and the development and improvement of the retrieval algorithms. The potential of the algorithm is demonstrated and examples of selected European coasts are shown. Derived maps of water constituents are presented.     

Modified Dry Column Procedure for Extraction of Lipids from Cured Meats

Polar lipids extracted from heated, nitrite-treated meats by a dry column procedure contain pigmented contaminants that interfere with subsequent analyses. Three modifications to the standard extraction procedure were studied: (a) changes in the composition of the trap, (b) insertion of additional material between column proper and trap, and (c) changes in the solvent system. Most satisfactory results were obtained by the addition of magnesium oxide to the trap (I). This resulted in the retention of impurities on the column and provided convenient, trouble-free operation. Polar lipids isolated in this manner were free of peroxides. Uncontaminated lipids were extracted from commercially processed meats by use of the modified procedure.     

Field-Property Bounds for Porous Sintered Ceramics

Three sets of equations provide upper and lower values bound ing the experimentally obtained electrical and thermal conduc tivities as well as the magnetic permeabilities (="field properties") of porous ceramics. These equations are as I-order upper bound: φ _p=φ_M (1 -P ) (φ=effective field property of the porous material, φ_M=field property of the nonporous material, P =porosity), and as I-order lower bound: φ_r=φ_M (1- P )⁷. Closer bounds corresponding to isotropic porous materials are the II-order upper bound: φ_P^II ,= φ _M ,[2(1- P)/ (2+P)], and the II-order lower bound: φ_PIII=φ_M(1- P)³ . Even closer bounds, referring to isotropic porous materials containing closed, unconnected pores are the III-order upper bound: φ_P^III = φ _M (1- P)^3/2 , and the III-order lower bound: φ_PIII = φ_M(1- p)3 .     

High-Temperature Centrifuge for Separation of the Liquid Phase from Refractories: II, Centrifuging Tests

A rotating-type induction furnace with graphite heater was used to demonstrate the application of the principles developed in Part I. Rotation at 1200 to 1300 r.p.m. for 15 minutes at an average temperature of 2560°F. (1405°C.) separated a low-melting slag from a silica brick which had been used in an open-hearth roof.