• Journal of Internet of Things and Convergence
• /
• v.8 no.1
• /
• pp.11-16
• /
• 2022

Efforts to incorporate blockchain into various fields are continuing as cryptocurrency transactions become more active. Blockchain has the characteristic that once recorded facts cannot be modified or deleted. Due to these characteristics, the use in the field of recording and proving certain facts, such as voting or proof of ownership, is attracting attention. In this paper, users who want to participate in the transaction process using private blockchain, one of the types of blockchain, are divided into real estate brokers, building owners, and purchasers (lessors), and roles are assigned to each user. In addition, we would like to propose a system to increase reliability through the participation of institutions. Through this, we intend to not only present a real estate transaction system that prevents damage from real estate fraud related to false sales and fraudulent contracts, but also enhances reliability and contributes to finding ways to utilize blockchain in the future.

• Environmental and Resource Economics Review
• /
• v.32 no.3
• /
• pp.149-166
• /
• 2023

The emissions trading system, introduced to reduce greenhouse gas emissions, experienced a sharp increase in emission allowance prices during the second plan period (2018-2020), which led to an increase in the demand for smooth supply and demand of emission allowances, while suppliers anticipating a shortage of emission allowances in the future did not participate in trading. Therefore, the authority temporarily revised the guidelines to ensure that the amount of allowances carried forward is proportional to the trading volume as a market stabilization measure. Through an optimization process using a dynamic nonlinear mathematical model, this paper analyzes the impact of the government's intervention on the carryover policy on GHG emission reductions and emission allowance market prices. According to the simulation analysis results, banking regulations could cause a decline in prices during the regulation period, even though the initial policy was predicted to be adopted.

• Development and Reproduction
• /
• v.11 no.3
• /
• pp.155-165
• /
• 2007

Gonad index (GI), conditon index, the reproductive cycle with gonadal development of the Neptunea (Barbitonia) arthritica cumingii, were investigated histologically, based on the samples which have been collected from the subtidal zone of Oeyeondo, Boryeong, Korea from January to December, 2006. Neptunea (Barbitonia) arthritica cumingii is dioecious and oviparous. Monthly changes in the gonad index (GI), studied for determination of spawning period, were closely associated with gonad developmental phases. The GI reached a maximum in April, and gradually decreased from May to August due to spawning. The gonadsomatic index and condition index showed similar patterns to gonad developmental phases and the spawning period. The reproductive cycle according to gonad developmental phases of this species can be classified into five successive stages in females and males: in females, early active stage (September to October), late active stage (November to February), ripe stage (February to June), partially spawned stage (May to August) and recovery stage (June to August); in males, the early active stage (September to October), late active stage (November to February), ripe stage (February to June), copulation (April to July), and recovery stage (July to August). Spawning occurred between May to August in females and April to July in males, and spawning peak in females was observed between June and July when the seawater temperature rose to above $19^{\circ}C$. Percentages of first sexual maturity of female and male snails ranging from $50.1{\sim}60.0\;mm$ in shell height were over 50%, and 100% for snails over 60.1 mm in shell height. The sex ratios of females to males were not significantly different from a 1:1 sex ratio.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.05a
• /
• pp.193-193
• /
• 2011

현재까지 대부분의 지열원 열펌프 시스템에 관한 연구는 열펌프 유닛과 지중열교환기에 대해 개별적으로 수행되었으며, 열펌프 유닛과 지중열교환기 설계 및 최적화의 공통변수인 지중순환수 유량에 따른 시스템 전체에 대한 연구성과는 매우 미미한 실정이다. 본 연구에서는 현재 국내에서 인증되어 보급되고 있는 물매물 지열원 열펌프 유닛의 성능 자료를 분석하고, 지중순환수 유량 변화에 따른 물대물 열펌프 유닛의 성능 실험 및 지중열교환기 형상에 관한 설계 및 분석을 수행하여 지열원 열펌프 시스템 최적화에 관한 기반 기술 확보하고자 하였다. 현재 국내의 물대물 지열원 열펌프 유닛의 냉방 및 난방 조건에서의 최소 인증 COP는 각각 4.1과 3.45이다. 다양한 용량 및 성능을 갖는 국내 인증 물대물 지열원 열펌프 유닛에 대한 정량적 성능 분석을 위하여 3.5kW(1RT) 용량당의 지중순환수 유량과 COP를 고찰하였다. 냉방운전시 3.5kW 단위 용량당 열펌프 유닛의 지중순환수 유량은 10.73에서 18.52LPM을 나타냈으며, 난방운전에는 10.41에서 18.16LPM을 나타냈다. 이때, 냉방 COP는 4.1에서 5.4의 값을 나타냈으며, 난방 COP는 각각 3.5에서 4.2를 나타냈다. 인증 열펌프 유닛에서 지중순환수 유량과 열펌프 유닛의 냉난방 성능은 일정한 경향성을 나타내지 않았다. 지중순환수 유량에 따른 지열원 열펌프 유닛과 시스템의 성능을 정량적으로 분석하고자 지중순환수 유량 변화에 따른 물대물 지열원 열펌프 유닛 성능 실험을 수행하고 이를 기반으로 지중열교환기를 설계 및 분석하였다. 냉난방 각 운전모드에서 ISO 13256-2 규격과 NRGT 101 규격을 기준으로 지중순환수와 부하측 유량 6LPM 에서 36LPM 사이에서 변화시키며 성능 실험을 수행하였다. 냉방 및 난방모드 모두 유량이 증가함에 따라 열펌프 유닛 COP가 증가하였으나, 유량 증가에 따른 열펌프 유닛 COP 증가율은 감소하였다. 지중순환수 유량이 18LPM 이상에서는 COP 상승폭은 미소하였다. 기존문헌의 부하 산정자료와 열펌프 유닛 실험 성능 데이터를 이용하여 지식경제부 고시 2009-332호에 준하여 수직밀폐형 지중열교환기를 설계하고 순환펌프 소요동력을 이용하여 시스템 COP를 분석하였다. 지중열교환기 설계 시 국내에서 가장 많이 사용되고 있는 상용지중열교환기 설계프로그램인 GLD 프로그램을 사용하였다. 지중순환수와 부하측 2차 유체 유량 증가 시에 열펌프 유닛 COP 증가율 대비 시스템 COP 증가율은 감소하였으며, 난방모드에서는 일정 유량 이상에서는 열펌프 유닛 COP는 증가하였으나, 시스템 COP는 감소하였다. 또한, 지중순환수 유량 증가에 따라 지중열교환기 길이가 증가하였으며, 냉난방시의 지중열교환기 길이차이가 증가하였다. 지열원 열펌프 시스템의 고효율화 및 시공비 절감을 통한 경제성 확보를 위해서는 지열원 열펌프 유닛 성능과 지중열교환기 형상 공통 변수인 지중순환수 유량을 함께 고려하여 시스템을 설계하여야한다.

• The Journal of Society for e-Business Studies
• /
• v.22 no.1
• /
• pp.51-64
• /
• 2017

After Bitcoin was proposed by Satoshi Nakamoto in 2009, studies have been carried out to apply the Block Chain technology in various environment, which was applied as a distributed transaction of Bitcoin. Smart contracts, voting and proof of ownership of digital contents are typical applications of Block Chain. They used the feature that it is impossible to modify or delete once recorded facts. They also applied to prove relevant facts and to provide data integrity. The applied cases are mainly made in an environment where the data should or could be open to the public, and they have been proposed as solutions to solve the problems occurred in relations. This fact has led to the attention that Block Chain can be applied as a good alternative in similar circumstances. In this study, real estate market service was selected to expand the application range of Block Chain. Although there are about 250 applications and web services in total, the satisfaction is not high due to false offerings. Thus we propose a countermeasure against the problem by applying the Block Chain to the real estate market service, and investigate the research direction of the Block Chain in the future market.

• Journal of Korea Society of Industrial Information Systems
• /
• v.16 no.2
• /
• pp.111-124
• /
• 2011

The apartment' share of the housing has steadily increased and property assets have been valued in importance as the one of asset value. Information retrieval system using internet is particularly active in the real estate market. However, user satisfaction on real estate information system is not very high, and there is a lack of research on real estate retrieval to increasing efficiency until now. This study presents a new knowledge information system developed to consider region-related factor and individual-related factor in the real estate market. In addition it enables a real estate knowledge system to search various preferential requirements for buyers such as school district, living convenience, easy maintenance as well as price. We made a survey of the search condition preference of experts on 30 real estate agents and then analyzed the result using AHP methodology. Furthermore, this research is to build apartment ontology using semantic web technologies to standardize various terminologies of apartment information and to show how it can be used to help buyers find apartments of the interest. After designing architecture of a real estate knowledge information system, this system is applied to the Busan real estate market to estimate the solutions of retrieval through Multi-Attribute Decision Making(MADM). Based on the results of the analysis, we endowed the buyer and expert's selected factors with weights in the system. Evaluation results indicate that this new system is to raise not only the value satisfaction of user, but also make it possible to effectively search and analyze the real estate through entropy analysis of MADM. This new system is to raise not only the value satisfaction of buyer's real estate, but also make it possible to effectively search and analyze the related real estate, consequently saving the searching cost of the buyers.

• Journal of KIISE:Software and Applications
• /
• v.29 no.1_2
• /
• pp.42-52
• /
• 2002

Information extraction(IE) is a process of recognizing and fetching particular information fragments from a document. In previous work, most IE systems generate the extraction rules called the wrappers manually, and although this manual wrapper generation may achieve more correct extraction, it reveals some problems in flexibility, extensibility, and efficiency. Some other researches that employ automatic ways of generating wrappers are also experiencing difficulties in acquiring and representing useful domain knowledge and in coping with the structural heterogeneity among different information sources, and as a result, the real-world information sources with complex document structures could not be correctly analyzed. In order to resolve these problems, this paper presents an agent-based information extraction system named XTROS that exploits the domain knowledge to learn from documents in a semi-structured information source. This system generates a wrapper for each information source automatically and performs information extraction and information integration by applying this wrapper to the corresponding source. In XTROS, both the domain knowledge and the wrapper are represented as XML-type documents. The wrapper generation algorithm first recognizes the meaning of each logical line of a sample document by using the domain knowledge, and then finds the most frequent pattern from the sequence of semantic representations of the logical lines. Eventually, the location and the structure of this pattern represented by an XML document becomes the wrapper. By testing XTROS on several real-estate information sites, we claim that it creates the correct wrappers for most Web sources and consequently facilitates effective information extraction and integration for heterogeneous and complex information sources.

• Land and Housing Review
• /
• v.12 no.4
• /
• pp.41-59
• /
• 2021

This study reviews theoretical considerations and past studies about real estate prices, macroeconomic variables, and real estate policies. Monthly data from January 2003 to June 2021 are used, and a VEC model, the most widely used multivariate time series analysis method, is employed for analysis. Through the model, the effects of macroeconomic variables and real estate regulatory policies on real estate prices in Seoul are analyzed. Findings are summarized as follows. First, macroeconomic variables such as money supply and interest rates do not have a significant impact on Seoul's apartment prices. Due to the high demand for housing and insufficient supply, there is a demand for buying a home regardless of macroeconomic booms or recessions. Second, tax and financial regulatory policies have an initial impact on the rise in apartment prices in Seoul, and their influence diminishes over time. Third, anti-speculation zones are expected to decrease apartment prices through the suppression of demand. However, these zones cause a rise in apartment prices. This could be understood as a lock-in effect due to the strengthening of capital gains tax. Fourth, the price ceiling did not decrease apartment prices. These findings propose that, in Seoul, where demand is high and supply is insufficient, the supply of high-quality and sufficient housing should be prioritized over various regulations such as tax regulations, financial regulations, anti-speculation zones, and price caps. Moreover, the findings provide an implication that city-specific real estate policies should be implemented for Seoul rather than regulation-oriented approaches in public policy.

• The Korean Journal of Air & Space Law and Policy
• /
• v.29 no.2
• /
• pp.239-272
• /
• 2014

The rights and obligations of the Member States of ITU in the domain of international frequency management of the spectrum/orbit resource are incorporated in the Constitution and Convention of the ITU and in the Radio Regulations that complement them. These instruments contain the main principles and lay down the specific regulations governing the major elements such as rights and obligations of member administrations in obtaining access to the spectrum/orbit resource, as well as international recognition of these rights by recording frequency assignments and, as appropriate, any associated orbits, including the geostationary-satellite orbits used or intended to be used in the Master International Frequency Register (MIFR) Coordination is a further step in the process leading up to notification of the frequency assignments for recording in the MIFR. This procedure is a formal regulatory obligation both for an administration seeking to assign a frequency in its network and for an administration whose existing or planned services may be affected by that assignment. Regulatory problem lies in allowing administrations to fulfill their "bringing into use" duty for preserving his filing simply putting any satellites, whatever nationlity or technical specification may be, into filed orbit. This sort of regulatory lack may result in the emergence of the secondary market for satellite orbit. Within satellite orbit secondary market, the object of transaction may be the satellite itself, or the regulatory rights in rem, or the orbit registered in the MIFR. Recent case of selling the Koreasat belongs to the typical example of orbit transaction between private companies, the legality of which remains doubtedly controversial from the perspective of international space law as well as international transaction law. It must be noted, however, that the fact is the Koreasat 3 and its filed orbit is for sale.