The USDJ ​Stablecoin SystemWhite Paper

https://just.network

By the JUST ​Team

I. About USDJ Stablecoin
II. USDJ Stablecoin System
III. Use Collateralized Debt Positions (CDPs) to Generate USDJ
1. Obtaining the collateral assets
2. Creating CDPs to deposit collateral assets
3. Generating USDJ through CDPs
4. Redeeming the collateral
IV. Price Stability Mechanism
V. Global Settlement Mechanism
1. Global Settlement is activated
2. Global Settlement claims are processed
3. USDJ and CDP holders claim their collateral
VI. Risk Management
1. Modification of Sensitivity Parameter
2. Modification of Target Rate
3. Choosing a set of trusted Oracles
4. Modification of Price Feed Sensitivity
5. Choosing a set of global setters
6. Setting up parameters for risk-control1). Debt ceiling2). Liquidation ratio
3). Stability fee
4). Penalty ratio
VII. JUST System Governance
1. Single action proposal contract
2. Delegating Proposal Contracts
VIII. Resources1

I. ​About USDJ ​Stablecoin

TRON network offers varieties of quality assets, but most of them are not viable for everyday
use because of their high volatility.
USDJ is a new currency generated through decentralized smart contracts on the TRON
network. Anyone can pledge ​TRX ​as collateral to generate ​USDJ​. ​USDJ enters into freecirculation as any other cryptocurrency does once generated. It is pegged to the US dollar
through Collateralized Debt Positions (​CDPs​), and also has autonomous feedback mechanisms.
USDJ Stablecoin is a USD-pegged cryptocurrency backed by collateral assets. We believe thatUSDJ​ will become an integral part of the TRON ​DeFi​ ecosystem.

II. ​USDJ​ Stablecoin SystemFigure 1. Core Mechanism of the ​JUST​ System

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USDJ mortgage lending system and decentralized autonomous incentive mechanism are thecore parts of JUST. Please find the details below.

III. Use Collateralized Debt Positions (​CDPs​) toGenerate ​USDJUSDJ​ is generated through depositing collateral assets into ​CDP​. Here are the steps:

1​. Obtaining the collateral assets
Exchange the ​TRX to be pledged for ​PTRX​, ​which is the only collateral assets accepted by thesystem for the moment.

2​. Creating ​CDP​s to deposit collateral assets
Send a transaction to ​JUST to create a ​CDP​, then send another transaction to deposit ​PTRX​,
the collateral asset, into the ​CDP​ to generate ​USDJ​.

3​. Generating ​USDJ​ through ​CDPs
The CDP holder sends a transaction to specify the amount of ​USDJ generated in the ​CDP​.
Meanwhile, the same amount of debt will be created, and the collateral asset is locked up andnot available for redemption until the debt is repaid.

4​. Redeeming the collateral
To redeem the collateral, the debt must be repaid with ​USDJ along with a stability fee paid withJUST platform token, ​JST​. Finally, ​CDP holders can send a transaction to ​JUST to retrieve allcollateral assets.
If a price slump of the collateral makes it at risk of being unable to cover the debt, the ​CDPliquidation will be triggered to auction the collateral for repayment. Any remaining value net ofthe debt and the penalty fee will be kept in the ​CDP​ for withdrawal.

3IV. Price Stability Mechanism
The starting Target Price of USDJ is pegged at ​1.0 to the US dollar. In the ​JUST system, ​USDJTarget Price serves two main functions​:1​. To calculate the debt-to-collateral ratio of the CDP.
2​. To determine the value of collateral assets that ​USDJ holders will receive upon GlobalSettlement.
In the event of market instability, a Target​ ​Rate​ ​Feedback​ ​Mechanism​ ​(TRFM) will be triggered
to maintain the same denomination of ​USDJ​. The​ ​Target​ ​Rate​ ​Feedback​ ​Mechanism​ is aprocess in which the ​USDJ Stablecoin System helps to adjust the Target Rate, so as to mobilize
market forces to maintain the stability of ​USDJ​ price.
The Target Rate determines the change of the Target Price, which incentivizes people to hold
USDJ when the value is positive and lend ​USDJ when it's negative. Such a feedback
mechanism maintains the market price of ​USDJ around the Target Price, thus dampening theprice volatility of ​USDJ​ and injecting liquidity during demand shocks.
Under the Target​ ​Rate​ ​Feedback​ ​Mechanism, once the market price of ​USDJ falls below theTarget Price, the Target Rate will increase, making it more expensive to generate ​USDJ withCDPs​. In the meantime, an increased Target Rate will drive up the capital gains of holding
USDJ​, thus increasing the demand for ​USDJ​. In this way, the reduced supply and increased
demand will push up the market price of ​USDJ​ back towards its Target Price.
Likewise, when the market price of ​USDJ rises above the Target Price, the same mechanism
takes effect by decreasing the Target Rate, and thus driving down the market price backtowards the Target Price.

V. Global Settlement Mechanism
When the ​USDJ price that the system receives from ​Oracles deviates drastically from the US
Dollar during a system attack or malicious control which causes intolerable risks within thesystem, global settlers designated by ​JST holders can trigger the Global Settlement Mechanismthat is carried out in the following steps:41​. Global Settlement is activated
After Global Settlement is activated, ​CDPs can no longer be created or adjusted and the Price
Feed will be frozen at a certain value to process all users' claims.

2​. Global Settlement claims are processed
Meanwhile, ​Keepers in the ​JUST system will auction the debt and collateral assets based on thefixed Price Feed in a decentralized way in order to process corresponding claims of all ​USDJand CDP holders.

3​. ​USDJ​ and CDP holders claim their collateral
After Keepers process all Global Settlement claims, each ​USDJ and ​CDP holder can submit aclaim request on ​JUST to directly exchange their ​USDJ or CDPs for a fixed amount of ​TRX
based on the Target Price of ​USDJ​. No time limit is set as for when users can take this step.

VI. Risk Management
To effectively manage and control potential risks, ​USDJ ​stablecoin system is armed with acomprehensive risk-management system. On one hand​, JST holders elect key decision makers
through their votes to regulate risks across the system. On the other hand​, JST ​holders mayalso vote with ​JST​ to participate in setting up and modifying the risk parameters.
Risk management consists of the following components:

1​. Modification of Sensitivity Parameter
Modify the sensitivity of the Target Rate Feedback Mechanism (TRFM).

2.​ Modification of Target Rate
Administrators may change Target Rate. In real practice​, when JST holders want to peg theprice of ​USDJ to the current Target Price, they may set Sensitivity Parameter and ​Target ​Rate
at zero to achieve the goal.

53.​ Choosing a set of trusted Oracles
JUST platform obtains the internal price of collateral and the market price of USDJ throughdecentralized Oracles. JST holders can control the number of Oracle nodes and designate
specific nodes as trusted Oracles. The system operates safely as long as over half of theOracles function properly.

4. ​Modification of Price Feed Sensitivity
Changes in Price Feed Sensitivity affects the system's internal prices to a certain extent.

5.​ Choosing a set of global setters
Global setter is a crucial mechanism for JUST platform to survive attacks against the Oracles
and the governance steps. The mechanism chooses a set of global setters and determines how
many global setters are needed to activate a global settlement.

6. Setting up ​parameters for risk-control
To maintain the stability of the price of USDJ, the JUST system sets up multiple parameters forrisk-control to regulate the Collateralized Debt Positions, all of which will be put up for vote anddetermined by JST holders.

1). Debt ceiling
Debt ceiling is the maximum ​amount of debt that can be created by CDP. Once the debt ceilingis reached, it becomes impossible for CDP to create new USDJ unless existing CDPs areclosed.

2). Liquidation ratio
Liquidation ratio is a ratio of the collateral-to-debt when a CDP ​is liquidated. A low liquidation
ratio means JST voters expect low price volatility of the collateral, while a high liquidation ratiomeans high volatility is expected.

63).​ Stability fee
A stability fee is the ​extra fee ​charged on users when they pay back the debt after borrowing
USDJ from CDPs. The stability fee is priced by USDJ and repaid only in JST. Once repaid, theJST will be burned and removed from the supply. The price of stability fee regulates theincentive of borrowing, and therefore controls the risk from the supply-and-demand end.

4). ​Penalty ratio

Penalty ratio is used to determine the maximum amount of ​USDJ bought and destroyed inliquidation auctions. The remaining collateral assets after the CDP liquidation will be refunded tothe CDP holders before the liquidation. Penalty ratio is used to improve the efficiency of theliquidation mechanism, and the liquidation penalty will be used to buy and burn PTRX,
benefitting the PTRX to TRX ratio.

VII. ​JUST ​System Governance
JUST ​system governance relies mainly on JST ​holders. While JST ​holders earn revenue fromthe stability fees of USDJ​, they are also responsible for the governance of the JUST ​system,
which is done through selecting valid proposals ​ by JST ​voters.
Each JST ​holder ​can vote and select the contract he/she supports among all the smart
contracts that modify the system parameters. The contract with the highest number of votes
becomes a valid proposal and has the system permit to modify variables of JUST ​internal
system governance as per the established logic. Valid contract proposals can be in two forms:

1​. Single action proposal contract
Single action proposal contracts are proposals that can only be executed after gaining the root
access, and after execution immediately applies its changes to the variables of internal systemgovernance. The single action proposal will delete itself and become invalid. It’s easy to use but
not flexible. This type of proposal will be adopted in the early stage of the system.

2​. Delegating Proposal Contracts
Delegating Proposal Contracts are proposals that continuously utilize their root access throughsecond layer governance logic. The second layer governance logic can be relatively simple,

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such as defining a protocol for holding a weekly vote on updated risk parameters. It can also
implement more advanced logic, such as restrictions on the magnitude of governance actions
within defined time periods, or even deleting permissions of its third layer Delegating Proposal
Contracts with restrictions.
There is no special requirement for proposal initiation. Any TRON account can submit
suggestions for improving the JUST ​system by deploying valid smart contracts. ​JST ​holders canuse their JST tokens to cast approval votes for one or multiple proposals that they want to selectas the valid proposal. This mechanism ensures that JST ​holders fulfill their obligation of
governance in a fair and just manner, and that suggestions carried in these valid proposals aresafely deployed in the​ JUST ​system.
We believe that under successful community governance, USDJ will bring into full play its
advantages as a stablecoin and be widely applied across the TRON network.

VIII. Resources
JUST Official Website:​ ​www.just.network
Product Website: ​just.tronscan.org

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