Atomic structure and periodic properties, stoichiometry, properties of gases, thermochemistry, chemical bond types, intermolecular forces, liquids and solids, chemical kinetics and introduction to organic chemistry and biochemistry. Corequisites: CH 117

General Chemistry Laboratory I (0-3-1)

(Lecture-Lab-Study Hours)

Laboratory work to accompany CH 115: experiments of atomic spectra, stoichiometric analysis, qualitative analysis, and organic and inorganic syntheses, and kinetics. Close

Laboratory work to accompany CH 115: experiments of atomic spectra, stoichiometric analysis, qualitative analysis, and organic and inorganic syntheses, and kinetics. Corequisites: CH 115,

General Chemistry I (3-0-6)

(Lecture-Lab-Study Hours)

Atomic structure and periodic properties, stoichiometry, properties of gases, thermochemistry, chemical bond types, intermolecular forces, liquids and solids, chemical kinetics and introduction to organic chemistry and biochemistry. Close

An introduction to differential and integral calculus for functions of one variable. The differential calculus includes limits, continuity, the definition of the derivative, rules for differentiation, and applications to curve sketching, optimization, and elementary initial value problems. The integral calculus includes the definition of the definite integral, the Fundamental Theorem of Calculus, techniques for finding antiderivatives, and applications of the definite integral. Transcendental and inverse functions are included throughout.

This is the first half of a one-credit, two-semester course that consists of a set of engineering experiences such as lectures, small group sessions, on-line modules and visits. Students are required to complete a specified number of experiences each semester and are given credit at the end of the second half of the course which is E102. The goal is to introduce students to the engineering profession, engineering disciplines, college success strategies, Stevens research and other engaging activities and to Technogenesis. Course is pass/fail.

This course introduces students to the process of design and seeks to engage their enthusiasm for engineering from the very beginning of the program. The engineering method is used in the design and manufacture of a product. Product dissection is exploited to evaluate how others have solved design problems. Development is started of competencies in professional practice topics, primarily: effective group participation, project management, cost estimation, communication skills and ethics. Engineering Design I is linked to and taught concurrently with the Engineering Graphics course. Engineering graphics are used in the design projects and the theme of "fit to form" is developed. Corequisites: E 115,

Introduction to Programming (1-2-3)

(Lecture-Lab-Study Hours)

An introduction to the use of an advanced programming language for use in engineering applications, using C++ as the basic programming language and Microsoft Visual C++ as the program development environment. Topics covered include basic syntax (data types and structures, input/output instructions, arithmetic instructions, loop constructs, functions, subroutines, etc.) needed to solve basic engineering problems as well as an introduction to advanced topics (use of files, principles of objects and classes, libraries, etc.). Algorithmic thinking for development of computational programs and control programs from mathematical and other representations of the problems will be developed. Basic concepts of computer architectures impacting the understanding of a high-level programming language will be covered. Basic concepts of a microcontroller architecture impacting the use of a high-level programming language for development of microcontroller software will be covered, drawing specifically on the microcontroller used in E121 (Engineering Design I). Close

Engineering graphics: principles of orthographic and auxiliary projections, pictorial presentation of engineering designs, dimensioning and tolerance, sectional and detail views, assembly drawings. Descriptive geometry. Engineering figures and graphs. Solid modeling introduction to computer-aided design and manufacturing (CAD/CAM) using numerically-controlled (NC) machines. Close

Engineering graphics: principles of orthographic and auxiliary projections, pictorial presentation of engineering designs, dimensioning and tolerance, sectional and detail views, assembly drawings. Descriptive geometry. Engineering figures and graphs. Solid modeling introduction to computer-aided design and manufacturing (CAD/CAM) using numerically-controlled (NC) machines.

An introduction to the use of an advanced programming language for use in engineering applications, using C++ as the basic programming language and Microsoft Visual C++ as the program development environment. Topics covered include basic syntax (data types and structures, input/output instructions, arithmetic instructions, loop constructs, functions, subroutines, etc.) needed to solve basic engineering problems as well as an introduction to advanced topics (use of files, principles of objects and classes, libraries, etc.). Algorithmic thinking for development of computational programs and control programs from mathematical and other representations of the problems will be developed. Basic concepts of computer architectures impacting the understanding of a high-level programming language will be covered. Basic concepts of a microcontroller architecture impacting the use of a high-level programming language for development of microcontroller software will be covered, drawing specifically on the microcontroller used in E121 (Engineering Design I).

This is a two-semester course that consists of a set of engineering experiences such as lectures, small group sessions, on-line modules and visits. Students are required to complete a specified number of experiences each semester and are given credit at the end of the semester. The goal is to introduce students to the engineering profession, engineering disciplines, college success strategies, Stevens research and other engaging activities and to Technogenesis.

Continues from MA 115 with improper integrals, infinite series, Taylor series, and Taylor polynomials. Vectors operations in 3-space, mathematical descriptions of lines and planes, and single-variable calculus for parametric curves. Introduction to calculus for functions of two or more variables including graphical representations, partial derivatives, the gradient vector, directional derivatives, applications to optimization, and double integrals in rectangular and polar coordinates.

An introduction to differential and integral calculus for functions of one variable. The differential calculus includes limits, continuity, the definition of the derivative, rules for differentiation, and applications to curve sketching, optimization, and elementary initial value problems. The integral calculus includes the definition of the definite integral, the Fundamental Theorem of Calculus, techniques for finding antiderivatives, and applications of the definite integral. Transcendental and inverse functions are included throughout. Close

An introduction to differential and integral calculus for functions of one variable. The differential calculus includes limits, continuity, the definition of the derivative, rules for differentiation, and applications to curve sketching, optimization, and elementary initial value problems. The integral calculus includes the definition of the definite integral, the Fundamental Theorem of Calculus, techniques for finding antiderivatives, and applications of the definite integral. Transcendental and inverse functions are included throughout. Close

Vectors, kinetics, Newton’s laws, dynamics or particles, work and energy, friction, conserverative forces, linear momentum, center-of-mass and relative motion, collisions, angular momentum, static equilibrium, rigid body rotation, Newton’s law of gravity, simple harmonic motion, wave motion and sound. Corequisites: MA 115

Calculus I (4-0-0)

(Lecture-Lab-Study Hours)

An introduction to differential and integral calculus for functions of one variable. The differential calculus includes limits, continuity, the definition of the derivative, rules for differentiation, and applications to curve sketching, optimization, and elementary initial value problems. The integral calculus includes the definition of the definite integral, the Fundamental Theorem of Calculus, techniques for finding antiderivatives, and applications of the definite integral. Transcendental and inverse functions are included throughout. Close

This course will continue the freshman year experience in design. The design projects will be linked to the Mechanics of Solids course (integrated Statics and Strength of Materials) taught concurrently. The engineering method introduced in Engineering Design I will be reinforced. Further introduction of professional practice topics will be linked to their application and testing in case studies and project work. Basic concepts of design for environment and aesthetics will be introduced.

This course introduces students to the process of design and seeks to engage their enthusiasm for engineering from the very beginning of the program. The engineering method is used in the design and manufacture of a product. Product dissection is exploited to evaluate how others have solved design problems. Development is started of competencies in professional practice topics, primarily: effective group participation, project management, cost estimation, communication skills and ethics. Engineering Design I is linked to and taught concurrently with the Engineering Graphics course. Engineering graphics are used in the design projects and the theme of "fit to form" is developed. Close

Ordinary differential equations of first and second order, homogeneous and non-homogeneous equations; improper integrals, Laplace transforms; review of infinite series, series solutions of ordinary differential equations near an ordinary point; boundary-value problems; orthogonal functions; Fourier series; separation of variables for partial differential equations.

Continues from MA 115 with improper integrals, infinite series, Taylor series, and Taylor polynomials. Vectors operations in 3-space, mathematical descriptions of lines and planes, and single-variable calculus for parametric curves. Introduction to calculus for functions of two or more variables including graphical representations, partial derivatives, the gradient vector, directional derivatives, applications to optimization, and double integrals in rectangular and polar coordinates. Close

Coulomb’s law, concepts of electric field and potential, Gauss’ law, capacitance, current and resistance, DC and R-C transient circuits, magnetic fields, Ampere’s law, Faraday’s law of induction, inductance, A/C circuits, electromagnetic oscillations, Maxwell’s equations and electromagnetic waves.

An introduction to differential and integral calculus for functions of one variable. The differential calculus includes limits, continuity, the definition of the derivative, rules for differentiation, and applications to curve sketching, optimization, and elementary initial value problems. The integral calculus includes the definition of the definite integral, the Fundamental Theorem of Calculus, techniques for finding antiderivatives, and applications of the definite integral. Transcendental and inverse functions are included throughout. Close

Vectors, kinetics, Newton’s laws, dynamics or particles, work and energy, friction, conserverative forces, linear momentum, center-of-mass and relative motion, collisions, angular momentum, static equilibrium, rigid body rotation, Newton’s law of gravity, simple harmonic motion, wave motion and sound. Close

Vectors, kinetics, Newton’s laws, dynamics or particles, work and energy, friction, conserverative forces, linear momentum, center-of-mass and relative motion, collisions, angular momentum, static equilibrium, rigid body rotation, Newton’s law of gravity, simple harmonic motion, wave motion and sound. Close

Fundamental concepts of particle statics, equivalent force systems, equilibrium of rigid bodies, analysis of trusses and frames, forces in beam and machine parts, stress and strain, tension, shear and bending moment, flexure, combined loading, energy methods, statically indeterminate structures.

An introduction to differential and integral calculus for functions of one variable. The differential calculus includes limits, continuity, the definition of the derivative, rules for differentiation, and applications to curve sketching, optimization, and elementary initial value problems. The integral calculus includes the definition of the definite integral, the Fundamental Theorem of Calculus, techniques for finding antiderivatives, and applications of the definite integral. Transcendental and inverse functions are included throughout. Close

Vectors, kinetics, Newton’s laws, dynamics or particles, work and energy, friction, conserverative forces, linear momentum, center-of-mass and relative motion, collisions, angular momentum, static equilibrium, rigid body rotation, Newton’s law of gravity, simple harmonic motion, wave motion and sound. Close

An introduction to differential and integral calculus for functions of one variable. The differential calculus includes limits, continuity, the definition of the derivative, rules for differentiation, and applications to curve sketching, optimization, and elementary initial value problems. The integral calculus includes the definition of the definite integral, the Fundamental Theorem of Calculus, techniques for finding antiderivatives, and applications of the definite integral. Transcendental and inverse functions are included throughout. Close

Ideal circuit elements; Kirchoff laws and nodal analysis; source transformations; Thevenin/Norton theorems; operational amplifiers; response of RL, RC and RLC circuits; sinusoidal sources and steady state analysis; analysis in frequenct domain; average and RMS power; linear and ideal transformers; linear models for transistors and diodes; analysis in the s-domain; Laplace transforms; transfer functions. Corequisites: MA 221,

Differential Equations (4-0-8)

(Lecture-Lab-Study Hours)

Ordinary differential equations of first and second order, homogeneous and non-homogeneous equations; improper integrals, Laplace transforms; review of infinite series, series solutions of ordinary differential equations near an ordinary point; boundary-value problems; orthogonal functions; Fourier series; separation of variables for partial differential equations. Close

Coulomb’s law, concepts of electric field and potential, Gauss’ law, capacitance, current and resistance, DC and R-C transient circuits, magnetic fields, Ampere’s law, Faraday’s law of induction, inductance, A/C circuits, electromagnetic oscillations, Maxwell’s equations and electromagnetic waves. Close

This course continues the experiential sequence in design. Design projects are linked with Mechanics of Solids topics taught concurrently. Core design themes are further developed. Corequisites: E 126

Mechanics of Solids (4-0-8)

(Lecture-Lab-Study Hours)

Fundamental concepts of particle statics, equivalent force systems, equilibrium of rigid bodies, analysis of trusses and frames, forces in beam and machine parts, stress and strain, tension, shear and bending moment, flexure, combined loading, energy methods, statically indeterminate structures. Close

This course will continue the freshman year experience in design. The design projects will be linked to the Mechanics of Solids course (integrated Statics and Strength of Materials) taught concurrently. The engineering method introduced in Engineering Design I will be reinforced. Further introduction of professional practice topics will be linked to their application and testing in case studies and project work. Basic concepts of design for environment and aesthetics will be introduced. Close

Introduction to logic, methods of proof, proof by induction and the pigeonhole principle with applications to logic design. Analytic functions of a complex variable, Cauchy-Riemann equations, Taylor series. Integration in the complex plane, Cauchy Integral formula, Liouville's theorem, maximum modulus theorem. Laurent series, residues, the residue theorem. Applications to system theory, Laplace transforms, and transmission lines.

Ordinary differential equations of first and second order, homogeneous and non-homogeneous equations; improper integrals, Laplace transforms; review of infinite series, series solutions of ordinary differential equations near an ordinary point; boundary-value problems; orthogonal functions; Fourier series; separation of variables for partial differential equations. Close

This course continues the experiential sequence in design. Design projects are in, and lectures address the area of Electronics and Instrumentation. Core design themes are further developed.

Ideal circuit elements; Kirchoff laws and nodal analysis; source transformations; Thevenin/Norton theorems; operational amplifiers; response of RL, RC and RLC circuits; sinusoidal sources and steady state analysis; analysis in frequenct domain; average and RMS power; linear and ideal transformers; linear models for transistors and diodes; analysis in the s-domain; Laplace transforms; transfer functions. Close

This course continues the experiential sequence in design. Design projects are linked with Mechanics of Solids topics taught concurrently. Core design themes are further developed. Close

Ideal circuit elements; Kirchoff laws and nodal analysis; source transformations; Thevenin/Norton theorems; operational amplifiers; response of RL, RC and RLC circuits; sinusoidal sources and steady state analysis; analysis in frequenct domain; average and RMS power; linear and ideal transformers; linear models for transistors and diodes; analysis in the s-domain; Laplace transforms; transfer functions. Close

Concepts of heat and work; First and Second Laws for closed and open systems including steady processes and cycles; thermodynamic properties of substances and interrelationships; phase change and phase equilibrium; chemical reactions and chemical equilibrium; representative applications. Introduction to energy conversion systems, including direct energy conversion in fuel-cells, photo-voltaic systems, etc.

Atomic structure and periodic properties, stoichiometry, properties of gases, thermochemistry, chemical bond types, intermolecular forces, liquids and solids, chemical kinetics and introduction to organic chemistry and biochemistry. Close

An introduction to differential and integral calculus for functions of one variable. The differential calculus includes limits, continuity, the definition of the derivative, rules for differentiation, and applications to curve sketching, optimization, and elementary initial value problems. The integral calculus includes the definition of the definite integral, the Fundamental Theorem of Calculus, techniques for finding antiderivatives, and applications of the definite integral. Transcendental and inverse functions are included throughout. Close

A study of the implementation of digital systems using microprocessors. The architecture and operation of microprocessors is examined in detail along with I/O interfacing, interrupts, DMA and software design techniques. Specialized controller chips for interrupts, DMA, arithmetic processing, graphics and communications are discussed. The laboratory component introduces hardware and software design of digital systems using microprocessors. Design experiments include topics such as bus interfacing, memory decoding, serial communications and programmable ports.

Design of differential amplifiers using BJTs or FETs, design of output stages (class B and class AB), output and input impedance of differential amplifiers, frequency response. Feedback amplifiers, Nyquist criteria, Nyquist plots and root loci, bode plots, gain/phase margins and application in compensation for operational amplifiers, oscillators, tuned amplifiers and filters (passive and active). A suitable circuit analysis package is used for solving many of the problems. Corequisites: E 232

Engineering Design IV (2-3-7)

(Lecture-Lab-Study Hours)

This course continues the experiential sequence in design. Design projects are in, and lectures address the area of Electronics and Instrumentation. Core design themes are further developed. Close

Introduction to the underlying phenomena and operation of solid state electronic, magnetic and optical devices essential in the functioning of computers, communications and other systems currently being designed by engineers and scientists. Charge carrier concentrations and their transport are analyzed from both microscopic and macroscopic viewpoints, carrier drift due to electric and magnetic fields in solid state devices is formulated and optical energy absorption and emission are related to the energy levels in solid-state materials. Diffusion, generation and recombination of charge carriers are combined with carrier drift to produce a continuity equation for the analysis of solid state devices. Explanations and models of the operation of PN, metal-oxide, metal-oxide-semiconductor and heterostructure junctions are used to describe diode, transistor, photodiode, laser, integrated circuit and other device operation.

This course continues the experiential sequence in design. Design projects are in, and lectures address the area of Electronics and Instrumentation. Core design themes are further developed. Close

An introduction is provided to the important engineering properties of materials, to the scientific understanding of those properties and to the methods of controlling them. This is provided in the context of the processing of materials to produce products.

Atomic structure and periodic properties, stoichiometry, properties of gases, thermochemistry, chemical bond types, intermolecular forces, liquids and solids, chemical kinetics and introduction to organic chemistry and biochemistry. Close

This course includes both experimentation and open-ended design problems that are integrated with the Materials Processing course taught concurrently. Core design themes are further developed. Corequisites: E 344

Materials Processing (3-0-6)

(Lecture-Lab-Study Hours)

An introduction is provided to the important engineering properties of materials, to the scientific understanding of those properties and to the methods of controlling them. This is provided in the context of the processing of materials to produce products. Close

Descriptive statistics, pictorial and tabular methods, measures of location and of variability, sample space and events, probability and independence, Bayes' formula, discrete random variables, densities and moments, normal, gamma, exponential and Weibull distributions, distribution of the sum and average of random samples, the central limit theorem, confidence intervals for the mean and the variance, hypothesis testing and p-values, applications for prediction in a regression model. A statistical computer package is used throughout the course for teaching and for project assignments.

Continues from MA 115 with improper integrals, infinite series, Taylor series, and Taylor polynomials. Vectors operations in 3-space, mathematical descriptions of lines and planes, and single-variable calculus for parametric curves. Introduction to calculus for functions of two or more variables including graphical representations, partial derivatives, the gradient vector, directional derivatives, applications to optimization, and double integrals in rectangular and polar coordinates. Close

Continues from MA 115 with improper integrals, infinite series, Taylor series, and Taylor polynomials. Vectors operations in 3-space, mathematical descriptions of lines and planes, and single-variable calculus for parametric curves. Introduction to calculus for functions of two or more variables including graphical representations, partial derivatives, the gradient vector, directional derivatives, applications to optimization, and double integrals in rectangular and polar coordinates. Close

An introduction to the mathematical methods used in the study of communications systems with practical applications. Discrete and fast Fourier transforms. Functions of a complex variable. Laplace and Z transforms.

Introduction to logic, methods of proof, proof by induction and the pigeonhole principle with applications to logic design. Analytic functions of a complex variable, Cauchy-Riemann equations, Taylor series. Integration in the complex plane, Cauchy Integral formula, Liouville's theorem, maximum modulus theorem. Laurent series, residues, the residue theorem. Applications to system theory, Laplace transforms, and transmission lines. Close

Review of matrix operations, Cramer’s rule, row reduction of matrices; inverse of a matrix, eigenvalues and eigenvectors; systems of linear algebraic equations; matrix methods for linear systems of differential equations, normal form, homogeneous constant coefficient systems, complex eigenvalues, nonhomogeneous systems, the matrix exponential; double and triple integrals; polar, cylindrical and spherical coordinates; surface and line integrals; integral theorems of Green, Gauss and Stokes. Close

Ideal circuit elements; Kirchoff laws and nodal analysis; source transformations; Thevenin/Norton theorems; operational amplifiers; response of RL, RC and RLC circuits; sinusoidal sources and steady state analysis; analysis in frequenct domain; average and RMS power; linear and ideal transformers; linear models for transistors and diodes; analysis in the s-domain; Laplace transforms; transfer functions. Close

Development of deterministic and non-deterministic models for physical systems, engineering applications and simulation tools for deterministic and non-deterministic systems. Case studies and projects.

Basics of cost accounting and cost estimation, cost-estimating techniques for engineering projects, quantitative techniques for forecasting costs, cost of quality. Basic engineering economics, including capital investment in tangible and intangible assets. Engineering project management techniques, including budget development, sensitivity analysis, risk and uncertainty analysis and total quality management concepts.

This course introduces students to the process of design and seeks to engage their enthusiasm for engineering from the very beginning of the program. The engineering method is used in the design and manufacture of a product. Product dissection is exploited to evaluate how others have solved design problems. Development is started of competencies in professional practice topics, primarily: effective group participation, project management, cost estimation, communication skills and ethics. Engineering Design I is linked to and taught concurrently with the Engineering Graphics course. Engineering graphics are used in the design projects and the theme of "fit to form" is developed. Close

This course will continue the freshman year experience in design. The design projects will be linked to the Mechanics of Solids course (integrated Statics and Strength of Materials) taught concurrently. The engineering method introduced in Engineering Design I will be reinforced. Further introduction of professional practice topics will be linked to their application and testing in case studies and project work. Basic concepts of design for environment and aesthetics will be introduced. Close

This course continues the experiential sequence in design. Design projects are linked with Mechanics of Solids topics taught concurrently. Core design themes are further developed. Close

This course continues the experiential sequence in design. Design projects are in, and lectures address the area of Electronics and Instrumentation. Core design themes are further developed. Close

This course addresses the general topic of selection, evaluation and design of a project concept, emphasizing the principles of team-based projects and the stages of project development. Techniques to acquire information related to the state-of-the-art concepts and components impacting the project, evaluation of alternative approaches and selection of viable solutions based on appropriate cost factors, presentation of proposed projects at initial, intermediate and final stages of development and related design topics. Students are encouraged to use this experience to prepare for the senior design project courses. Corequisites: EE 345,

Modeling and Simulation (3-0-3)

(Lecture-Lab-Study Hours)

Development of deterministic and non-deterministic models for physical systems, engineering applications and simulation tools for deterministic and non-deterministic systems. Case studies and projects. Close

Basics of cost accounting and cost estimation, cost-estimating techniques for engineering projects, quantitative techniques for forecasting costs, cost of quality. Basic engineering economics, including capital investment in tangible and intangible assets. Engineering project management techniques, including budget development, sensitivity analysis, risk and uncertainty analysis and total quality management concepts. Close

This course includes both experimentation and open-ended design problems that are integrated with the Materials Processing course taught concurrently. Core design themes are further developed. Close

Introduction to the theory and design of digital signal processing systems. Include sampling, linear convolution, impulse response, and difference equations; discrete-time Fourier transform, DFT/FFT, circular convolution, and Z-transform; frequency response, magnitude, phase and group delays; ideal filters, linear-phase FIR filters, all-pass filters, minimum-phase and inverse systems; digital processing of continuous-time signals.

An introduction to the mathematical methods used in the study of communications systems with practical applications. Discrete and fast Fourier transforms. Functions of a complex variable. Laplace and Z transforms. Close

Review of probability, random processes, signals and systems; continuous-wave modulation including AM, DSB-SC, SSB, FM and PM; superheterodyne receiver; noise analysis; pulse modulation including PAM, PPM, PDM and PCM; quantization and coding; delta modulation, linear prediction and DPCM; baseband digital transmission, matched filter and error rate analysis; passband digital transmission including ASK, PSK and FSK.

Descriptive statistics, pictorial and tabular methods, measures of location and of variability, sample space and events, probability and independence, Bayes' formula, discrete random variables, densities and moments, normal, gamma, exponential and Weibull distributions, distribution of the sum and average of random samples, the central limit theorem, confidence intervals for the mean and the variance, hypothesis testing and p-values, applications for prediction in a regression model. A statistical computer package is used throughout the course for teaching and for project assignments. Close

An introduction to the mathematical methods used in the study of communications systems with practical applications. Discrete and fast Fourier transforms. Functions of a complex variable. Laplace and Z transforms. Close

Senior design course. The development of design skills and engineering judgment, based upon previous and current course and laboratory experience, is accomplished by participation in a design project. Projects are selected in areas of current interest such as communication and control systems, signal processing and hardware and software design for computer-based systems. To be taken during the student's last fall semester as an undergraduate student.

A continuation of EE 423 in which the design is implemented and demonstrated. This includes the completion of a prototype (hardware and/or software), testing and demonstrating performance and evaluating the results. To be taken during the student's last spring semester as an undergraduate student.

Senior design course. The development of design skills and engineering judgment, based upon previous and current course and laboratory experience, is accomplished by participation in a design project. Projects are selected in areas of current interest such as communication and control systems, signal processing and hardware and software design for computer-based systems. To be taken during the student's last fall semester as an undergraduate student. Close

Basic Science electives ? note: engineering programs may have specific requirements
- one elective must have a laboratory component
- two electives from the same science field cannot be selected

(3)

Credit applied in E101 & 102.

(4)

Core option – specific course determined by engineering program

(5)

Core option ? specific course determined by engineering program

(6)

Discipline specific courses

(7)

General Education Electives ? chosen by the student
- can be used towards a minor or option
- can be applied to research or approved international studies