Resolving operational and performance problems encountered in the use of a pilot/full-scale biotrickling filter reactor

1999 ◽  
Vol 18 (3) ◽  
pp. 162-172 ◽  
Author(s):  
Todd S. Webster ◽  
Huub H. J. Cox ◽  
Marc A. Deshusses
2000 ◽  
Vol 16 (2) ◽  
pp. 107-114 ◽  
Author(s):  
Louis M. Hsu ◽  
Judy Hayman ◽  
Judith Koch ◽  
Debbie Mandell

Summary: In the United States' normative population for the WAIS-R, differences (Ds) between persons' verbal and performance IQs (VIQs and PIQs) tend to increase with an increase in full scale IQs (FSIQs). This suggests that norm-referenced interpretations of Ds should take FSIQs into account. Two new graphs are presented to facilitate this type of interpretation. One of these graphs estimates the mean of absolute values of D (called typical D) at each FSIQ level of the US normative population. The other graph estimates the absolute value of D that is exceeded only 5% of the time (called abnormal D) at each FSIQ level of this population. A graph for the identification of conventional “statistically significant Ds” (also called “reliable Ds”) is also presented. A reliable D is defined in the context of classical true score theory as an absolute D that is unlikely (p < .05) to be exceeded by a person whose true VIQ and PIQ are equal. As conventionally defined reliable Ds do not depend on the FSIQ. The graphs of typical and abnormal Ds are based on quadratic models of the relation of sizes of Ds to FSIQs. These models are generalizations of models described in Hsu (1996) . The new graphical method of identifying Abnormal Ds is compared to the conventional Payne-Jones method of identifying these Ds. Implications of the three juxtaposed graphs for the interpretation of VIQ-PIQ differences are discussed.


1996 ◽  
Vol 12 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Louis M. Hsu

The difference (D) between a person's Verbal IQ (VIQ) and Performance IQ (PIQ) has for some time been considered clinically meaningful ( Kaufman, 1976 , 1979 ; Matarazzo, 1990 , 1991 ; Matarazzo & Herman, 1985 ; Sattler, 1982 ; Wechsler, 1984 ). Particularly useful is information about the degree to which a difference (D) between scores is “abnormal” (i.e., deviant in a standardization group) as opposed to simply “reliable” (i.e., indicative of a true score difference) ( Mittenberg, Thompson, & Schwartz, 1991 ; Silverstein, 1981 ; Payne & Jones, 1957 ). Payne and Jones (1957) proposed a formula to identify “abnormal” differences, which has been used extensively in the literature, and which has generally yielded good approximations to empirically determined “abnormal” differences ( Silverstein, 1985 ; Matarazzo & Herman, 1985 ). However applications of this formula have not taken into account the dependence (demonstrated by Kaufman, 1976 , 1979 , and Matarazzo & Herman, 1985 ) of Ds on Full Scale IQs (FSIQs). This has led to overestimation of “abnormality” of Ds of high FSIQ children, and underestimation of “abnormality” of Ds of low FSIQ children. This article presents a formula for identification of abnormal WISC-R Ds, which overcomes these problems, by explicitly taking into account the dependence of Ds on FSIQs.


1990 ◽  
Vol 22 (7-8) ◽  
pp. 35-43
Author(s):  
K. D. Tracy ◽  
S. N. Hong

The anaerobic selector of the A/0™ process offers many advantages over conventional activated sludge processes with respect to process performance and operational stability. This high-rate, single-sludge process has been successfully demonstrated in full-scale operations for biological phosphorus removal and total nitrogen control in addition to BOD and TSS removal. This process can be easily utilized in upgrading existing treatment plants to meet stringent discharge limitations and to provide capacity expansion. Upgrades of two full-scale installations are described and performance data from the two facilities are presented.


Author(s):  
D.S. Sax Saxena

The Specialty That Deals With Investigation Of Failures And Performance Problems In The Geotechnical Environment Is Known As Forensic Geotechnical Engineering. It Involves Scientific And Jurisprudence Related Investigations And Evaluation To Analyze The Causes Of Structural Distress That Originate From Geodomain. Forensics In The Geo-Domain Encompass An Extensive Array Of Topics With Specific Emphasis In Geotechnical Related Fields. Mostly, They Apply To Failures After They Occur. Such Analysis And The Evaluation Of Selected Remedial Measures, Along With Their Effectiveness And Economy, Are Normally Subjected To Judicial Scrutiny. A Case History Is Presented Where Forensic Engineering Was Effectively Utilized To Identify, Investigate, And Remediate The Problem As Well As Assist In Litigation.


2015 ◽  
Vol 77 (9) ◽  
Author(s):  
Adila Firdaus ◽  
Imran Ghani ◽  
Dayang Norhayati Abg Jawawi ◽  
Wan Mohd Nasir Wan Kadir

Agile methodologies are well known for early and frequent releases. Besides, these methodologies also handle requirement changes well without causing delays. However, it has been noticed that the functional requirements changes can affect the non-functional requirements (NFRs) such as security and performance. It is also possible that the agile team is not even aware of these effects causing dysfunctional system. This issue could be addressed by offering traceability mechanism that helps to trace the effect of functional requirement changes on the non-functional requirements. Unfortunately, a few researchers have conducted studies regarding this issue. Thus, this study attempts to present a Traceability Process Model (TPM) to tackle the issue of tracing NFR especially security and performance. However, to materialize a full scale TPM, a metamodel is necessary. Therefore in this paper, we present a metamodel by integrating two existing metamodels. Then we validate the newly built metamodel with precision and recall methods. Lastly, we also develop a traceability tool that is based on the proposed metamodel.


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