## Question about numbering of internal nodes in circuit diagrams when one circuit element has more than 1 internal node

I have the following circuit diagram that I’ve added labels for the internal nodes to using outside sources. I understand what an internal node is, however what I’m confused about is– for example– E1 has 2 wires connected to another circuit element, so they’re both internal nodes, but how do I distinguish which is n1? Or is this completely arbitrary?

And why is n2 after E4 here, is it because it has to follow the flow of the circuit?

Sorry for the noob question, my book doesn’t explain this (at least so I’ve read, I could be missing it).

## Adder-Subtractor Circuit With Negative Results

So, I understand how binary arithmetic works, and I understand how an adder-subtractor works for signed numbers. There is only one thing I am not sure about:

All the cases work ok in the circuit I have, except if the result of a subtraction is negative, I need to take the two’s complement of the output byte to get the actual result. What can I do about it? Do I need an extra array of adders to compute the two’s complement only in that specific way, or is there any smarter solution I can apply?

## What can this circuit be useful for?

I have calculated the boolean functions for $$r$$ and $$f$$:

$$f = \overline{s_1} \cdot s_0 + s_1 \cdot \overline{s_0}$$.

$$r = \overline{s_0 \cdot s_1 \cdot s_2 \cdot s_3}$$.

Do you have an idea what an application for this circuit can be? I don’t know where we would use it.

## Problem with understanding Multi-party security circuit for secure stable matching

I am reading the following paper: MPCircuits: Optimized Circuit Generation for Secure Multi-Party Computation

I have following questions:

1. why Preference of group1 starts from L_0 where as preference list from group2 starts with L_(n/2+1)?
2. Any reason why they used the priority encoder?
3. What is the technique for the security of preference list?

## Understanding the Secure Multi-party circuit for Stable Matching

I am reading the following paper:

MPCircuits: Optimized Circuit Generation for Secure Multi-Party Computation

I have following questions:

1. why Preference of group1 starts from L_0 where as preference list from group2 starts with L_(n/2+1)?

2. Any reason why they used the priority encoder?

3. Is their anything done for security of preference list ?

## Proof that uniform circuit families can efficiently simulate a Turing Machine

Can someone explain (or provide a reference for) how to show that uniform circuit families can efficiently simulate Turing machines? I have only seen them discussed in terms of specific complexity classes (e.g., $$\mathbf{P}$$ or $$\mathbf{NC}$$). I would like to see how uniform circuit families is a strong enough model for universal, efficient computation.

## Example of *small* non monotone circuit such that any equivalent monotone circuit has greater size?

A “general” Boolean (combinatoiral) circuit is a labeled (with the labels: AND, OR, NOT, IN, OUT), directed, acyclic graph, that satisfies:

1. fan-in=2 for the AND and OR nodes
2. fan-n=1 for the NOT nodes
3. fan-in=0 for the IN nodes
4. fan-out=0 to exactly one node (the OUT node)
5. Unbounded fan-out to the rest of the nodes (but the OUT node)

A monotone circuit is a Boolean circuit with 0 vertices labeled as “NOT”.

The size of a circuit is the number of “gates” (vertices with labels “AND”, “OR” or “NOT”) it contains.

In Yuval’s answer here I’ve learned of two examples (Tardos function and bipartite perfect matching) where it has been proven that monotone circuits admit greater size than general Boolean circuits, but I cannot get the intuition, as I don’t have any concrete small size example in hand.

Hence, my question is: could you please supply me with an example of a small (say, up to 10-20 gates) non monotone circuit such that any equivalent monotone circuit has greater size?

## Boolean circuit multigraph

Let us say that our definition of a circuit is the one of a boolean circuit from [Vollmer]. He uses directed acyclic graphs to represent circuits where the computation nodes are labeled with some functions which come from a set of possible operations (called basis).

Let us say that we only allow the operation $$\land$$ for our circuit (i.e. the basis only consists of $$\land$$). Is $$x \land x$$ a circuit if $$x$$ denotes an input gate? I don’t think so, because the input gate $$x$$ is only allowed to occure once in the graph and then we would need two edges to the $$\land$$-node, i.e. we would need a multigraph. A way around would be to force a basis to have an identity operation. For instance using the basis $$\land, id$$ we could of course build the $$x \land x$$ circuit (this is also the case if we can build the identity operation in any other way, e.g. if we have $$\neg$$ in our basis) even though we have to increase the size of the circuit by using $$id$$. It seems very counterintuitive that such a simple circuit is in fact not a circuit over the basis $$\land$$, so is my reasoning correct?

[Vollmer] Heribert Vollmer, Introduction to Circuit Complexity

## 125A 4P Molded Case Circuit Breaker in stock

Zhejiang Safesave Electrical Technology Co., Ltd was invested and build by Shanghai Shuen Electrical Technology Co., Ltd. Safesave focuses on high- voltage and low-voltage electrical equipment, electrical complete units and industrial automation devices. Our products have been applied to some national key projects such as Shanghai World Expo, Beijing Olympic stadiums, South–to-North Water Division Project, Pudong international airport. Meanwhile , the factory was titled as a high-technology enterprise, science and technology enterprise, software enterprise, advanced enterprise in quality management, etc.
Our company cooperates with the partners from outstanding university research units such as Mechanical and Electrical Engineering and Automation Academy of Shanghai University, Information and Technology Academy of Fudan University. After the reorganization, the factory will do further research and manufacturing in high-end industrial automation equipment on the basis of previous achievement in the field of soft starter and variable frequency drive.
Brief Company’s Developing History
In 2000——The first thyristor motor soft starter was developed with independent research, making our company one of the earliest manufacturers of the soft starter in China;
In 2003——The factory was moved to Shanghai；
In 2005——The second generation of intelligent soft starter and the variable frequency drive were certified as Shanghai new and high technology transformation achievements;
In 2006——Identified as Shanghai high-tech enterprise;
In 2007——A new generation of vector variable frequency drive was put into large-scale production;
Moved into Caohejing Economic and Technological Development Zone of Shanghai City
In 2008——Products were applied to the swimming center and shooting center of Beijing Olympic Games in batches.
In 2010——Production was applied in Shanghai World Expo;
Build up cooperation relationship with Fudan university optoelectronic department and Organize the photovoltaic inverter research laboratory.
In 2014——Regrouped and moved to Songjiang national economic and technological development zone of Shanghai City;
Build up strategic cooperation relationship with Chint Group and Delix Group, and became the sole official supplier of the core inverting components of EPS power products for the two groups.
In 2015——SY9000 devises were successfully developed and put into trial-production;
Meanwhile, the professional research team of servo motor and servo controller were organized.
In 2016——A new setting-free, quick-start, compacted, foolproof soft starters named SJR3—N has been developed successfully and put into trial-production.
Safesave’s Culture
Mission:
To create a greener world with our safe and energy-saving technology.
Vision:
To be a happy corporation benefiting human society.
Values:
Gratitude: Thankfulness for God’s grace, team cooperation and clients’ trust.
Credibility: Fruitful promise and resultful action.
Dedication: Persistence in seeking for professional perfection.
Teamwork: A promotive spirit of sharing, cherishing , cooperation and positive mutual influence .
Responsibility:Courage of taking responsibility for whatever result with no excuse.
Passion: Full energy and fighting will.
Learning: Consistent learning of professional skills to gain efficient working ability.
Innovation: A force to change the backward and lead the market.
Sharing: Growth in what we share.
The R&D Team
1.Structure of the R &D Center
The R&D center of Zhejiang Saikong Electrical Technology consists of three sections, namely, Electronic Design( systematic analysis and electronic circuits), Structural Design(heat dissipation design, configuration design), and Measurement and Verification(simulation and analysis, test and verification)
The R &D center has an experienced research and development team, working closely with Scientific Research Departments of the Institute of Mechanical and Electrical Engineering and Automation of Shanghai University, the Science and Technology Institute, and the Information Technology Department of Fudan University.
With years of efforts, Saikong has developed more than 100 models of 10 series of products by our outstanding talents and technology.
2.Business range & Achievements in recently years.
The R &D center’s design mainly covers two areas: power electronics； energy-saving and emission-reduction. Main products includes mid-low voltage soft starter, mid-low voltage frequency converter, AC servo controller，servo motor, etc.
During the years from 2013 to 2016, the R &D center has successfully developed SST type of intelligent soft starter with built-in bypass, SJR3 series of intelligent soft starter, 5000 type of online intelligent soft starter with built-in bypass, SN-100G series, SY9000 series of open loop vector inverter, G5 series of closed-loop vector inverter, SN-200G series of closed-loop vector inverter, waterproof type of inverter, EPS uninterruptible power supply, permanent magnet synchronous motor and etc., totally more than 100 models of 10 series of products. Meanwhile, we have completed the corresponding CAPP system of computer aided process planning , sound product database and process documents, etc.of each series of products.
Meanwhile, the center has applied for over twenty technical patents, including 4 invention patents, 14 patents of new utility models, 6 structure patents, 3 software copyright patents. Up until the end of 2016, 3 of our new invention patents have been publicly announced and are to be approved.
In recent years , led by a trend of miniaturization, intelligence, networking, and profession in product development, a batch of new high-tech products have been developed in succession, such as SST type of intelligent soft starter , 5000 type of online intelligent soft starter, SN-200G series of closed-loop vector inverter, which has greatly raised the popularity and reputation of our company in this field. Along with increasing application of our products in the fields of manufacturing, elevatoring, hoisting, machine tooling, printing&packaging, textile&chemical fibre, constructuring, metallurgy, mining, metro, etc, Saikong is making a great contribution to the cause of automatic control , energy-saving and emission-reduction for our country with our advanced and reliable products.
3.Investments on our R &D center.
To enhance the competence in the business field and and creativity for the sustainable development of our company, Saikong places high priority to the scientific research capability, keeping aggrandizing the investment and strength of research for new products. R & D investment takes over 30% of the total budget, and the R &D crew takes up 24.6% of the whole workforce.
4.Brief introduction of key staff at the R &D center
The R &D team is lead by Professor Zhao, the chief engineer, who has been in the field of power electronic for many years and who has been devoted into researching and developing a new generation’s frequency converter, soft starter, servo controller, servomotor. A complete set of solutions including proposal selection, structure designing, hardware designing, software designing, testing, quality guarantee, is delivered from our main researching staff of over 8 years’ industrial experience on average.
The center now has 25 staff, the majority were graduated from key universities majored in telecom, electric machinery. Among them, there are two professor of advanced engineers, 8 senior engineers, 14 engineers.Meanwhile, we also hire industrial-renowned experts in inverter/designing/technics as our consultants.
Engineer ZhaoTechnical director/Chief engineerBorn in 1972, aged 45, Eng. Zhao is working with Electric Machinery Institute of Shanghai University as supervisor for students of bachelors, masters and doctors.Having been long engaged in designing and developing hardware and software relevant to electronic inverting technology in power field, integrated with capabilities of project management, systemic analyse and designing , having been worked as technological chief supervisor or chief engineer in succession in several big companies, and having developed more than 100 new models of 10 series of products of inverters, soft starters, servo controllers and solar inverters, Eng. Zhao is now enjoys very good reputation in the industry.
Engineer LiProject engineer/System utility engineerBorn in 1961, aged 56, with Bachelor’s Degree majored in Industry Automation. Eng. Li is a pioneer in designing low-voltage soft starter in China. As the earliest designer of low-voltage soft starter in China, he led the designing of China’s first generation of soft starter and achieved success.
Engineer WangHardware engineerBorn in 1978, aged 38, with Master’s Degree, majored in Electronic Information Engineering Technology. Eng. Wang has been engaged in researching and development of frequency converter for many years, and has insightful views in SMPS and inverter drive.
Engineer YiSoftware engineerBorn in 1979, aged 37, with Master’s Degree.Having long been engaged in software compiling, Eng. Yi is very familiar with all types of software coding tools, and has good working capability and industrial experience.
Engineer ZhuHardware engineerBorn in 1981, aged 35, with Bachelor’s Degree, graduated from Hefei Industrial University, majored in Engineering Automation.Expertised in systemic adjustments, techinical identification, Eng. Zhu has insightful views in electronic circuit, data collecting, failure analysis.
5.Decent experiment environment.
To guarantee the reliability of the products that have been developed, the center established two well-equipped high-standard labs that cover 500 square meters.One serves to test regular features and performance.The other is to conduct performance tests under extreme circumstances.
We purchased complete equipments despite of high cost to enable the experimental process from simulating the spot environment, technic data collecting, to data processing and technique analysis digitized, visualized, and trackable. Each sample product is no longer a sample but a device having experienced practical application, and each data is no longer lab data but high-simulated spot data. In this way we fundamentally guarantee data accuracy at the spot environment and full-time reliability of the products.
List of main experimental equipment at R &D center
NO.Equipment /InstrumentFunction
1Standard equipment and standard devices:
Voltage source (constant voltage, adjustable), current source (constant current, adjustable), signal source (adjustable), standard resistance, standard capacitance, standard inductance, etc..To guarantee the accuracy of all the equipments and testing data.
2Testing equipments for regular data:
Voltage meter, current meter, multimeter, clamp meter, megger, small signal RMS current meter, DC current generator, oscilloscope, LCR BridgeRegular data of general voltage, current, resistance, capacitance, inductance, signal waveform tests
3A variety of test equipments for special parameters:
Power analyzer, spectrum analyzer, power analyzer, thermal zone imager, temperature management instrument, tachometer, flow meter, pressure gauge, balance machine etc..For testing of special parameter data and the data collected under specific circumstances.Such as test s for temperature, wind speed, flow, pressure, turning speed, strength of magnetic field, balance, coil rolling, wire diameter and power factor analysis, frequency spectrum analysis.
4A variety of special test equipments:
NC high pressure machine, surge generator, pulse group generator, etc.To test data parameters for special projects, such as high voltage protection, creepage distance, electrical clearance, EMC interference, lightning resistance, etc.
5A variety of equipments simulating field work environment:
NC high temperature chamber （0-300°C）, NC low temperature chamber （0- minus 150°C）, automatic ON/OFF experiment system, dust test box, acid/salt fog test box, shaft to drag load system (0-1000A, AC), vibration testing system(1-200KG), drop test equipment etc..For testing of the performance and data of spare parts or complete equipment which operate under extreme circumstances.To ensure the products work in all regions in high reliability.
6Various reliability test equipments:
Automatic ON/OFF aging room, high and low temperature cycle impact equipment, high temperature aging chamber with load, anti interference test room, etc.To test the reliability, stability, consistency, device life and other parameters of the components or the whole machine.
6. R&D Orientation in future
Along with society development, technical progress, and the revolutionary changes in the fields of domestic industrial automation control, energy-saving and emission-reduction, our R&D center keeps refreshing percepts , optimizing the products. Oriented by the goal to achieve miniaturization, multi-function, digitization, network, specialization and modularization, we believe, in the very near future the new products launched by our R&D center will dominate the industry.
7.Strict management system and practical working style
“No best, only better”
This is the working attitude and pursuit of our R&D center.
“Engaged in the basic work, down to the earth to try the best in everything.”
This is the basic requirement set by our own R &D members.
At the R &D center, design work is processed in modular, plural and step procedure, and management weighs responsibility, data and performance.The center highly values coordination among departments and among managers, and emphasizes the whole team’s working efficiency.
For each project, the center has clear target and thoughts. To complete the project, the center adopts quantitative management. Specific division of labor is distributed to each person and node time is set on daily basis so that the whole team becomes a strong, cohesive and centripetal force, working like a sophisticated engine to achieve a shared output target through all parts’ orderly, tensive and enthusiastic work.
FAQ
Q1: Are you a manufacturer or a trading company?
A1: We are a manufacturer.
Q2: Can I get some samples?
A2: Yes, sample order is available for quality check and market test. After we receive the sample charge, the samples will be delivered in 7-15 days.
Q3: Can you do the design for us?
A3: Yes. We have a professional designing team. Just tell us your ideas and we will help to carry out your ideas. Send us high resolution images, your Logo and text and tell us how you would like to arrange them, We will send you finished files for confirmation.
Q4: What about the delivery time?
A4: It depends on the quantity and the season you place the order. It usually takes about 7-15 days for production.
Q5: What is your terms of delivery?
A5: We accept EXW, FOB, CFR, CIF, etc. You can choose the one which is the most convenient or cost effective for you.