Tonight's Venus sighting

Venus taken with Canon SX50 HS
Thinner, larger
Venus keeps coming closer to the Earth, and it's getting visually larger from here. But since it's in the inner orbit, the crescent is getting thinner as well. Take a look at how it looked like two weeks ago and four weeks ago to see what I mean. I'll be keeping track of the planet regularly as it keeps coming closer. It'll be closest to the Earth almost exactly six weeks from now (January 11, 2014).

Settings: Canon SX50 HS - 1200mm (2x enlarged) - ISO 80 - 1/250s - f/6.5
Filters: Baader M&S applied
Time: 2013-11-30 17:47 KST
Location: Suwon, Korea
17 photos stacked with RegiStax 6.1.0.8
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Winter is coming, so we prepare

KPX's situation room during an electricity supply-demand emergency drill
Getting ready for the surging winter electricity demand

As the summer and winter peak demands for electricity in Korea get precariously close to the available supply capability in the recent years, KPX has been operating a contingency plan situation room for power shortage. To sharpen the skills of the people who man the stations, routine emergency drills are carried out, like this one today.

Since I'm one of those people, I participated, practicing all the things that I need to do in each alert level. The fast pace of the exercise reminded me that being calm, prompt, and accurate was crucial. Winter will soon be upon us, but we're ready to deal with what it'll throw at us.
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Comical patching of the Seoul subway map

Comparison of Seoul metropolitan subway line maps before and after Bundang Line extension
Before & After: Subway line map not futureproof? Make a big patch!

Extension of the Bundang Line in the Seoul metropolitan subway network will be complete in two days after a 5-year delay. This yellow-coloured line starts at Wangsimni station in the eastern Seoul and will extend to the south to Suwon station (currently 4 stations short at Mangpo station), while passing through Bundang district in Seongnam, which is where the name comes from.

Trouble is, this north-south line needs to be laid out horizontally on a super-wide line map pasted on top of the doors of the subway cars. Suwon station is already on Line 1, which is another line to go north-south, and this dark blue line is drawn from top right to bottom left. So the station sits at the bottom left corner of the map.

Meanwhile, Bundang line starts at around the middle and weaves towards bottom right on the maps installed in Seoul Metro (responsible for Lines 1 through 4) subway cars. In order for the line to meet up at Suwon station, it needs to make a sharp turn at the bottom and make a long run from right to left. Clearly, the map designer didn't think ahead, despite the plans for extension existing for a better part of a decade.

I thought this was a good time for the map to be overhauled. It already received several patches all over the place in the last couple of years. But no, Seoul Metro just put an incredibly long patch at the bottom of the map to connect Bundang line and Line 1, as you can see in the comparison picture. That's comically sad.
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Cellphone frequency in Korea: 1996 - 2000

On January 1, 1996, KMTC became the first company in the world to commercially operate the digital CDMA (2G) cellular service. Shinsegi Telecom(신세기통신; STI) followed up with its own CDMA service on April 1 of the same year. The allocated frequencies were the same as AMPS, and existing AMPS service would be gradually transitioned to CDMA, as per Ministry of Information and Communication (정보통신부; MIC) Notice No.1995-83(Jun. 15, 1995). AMPS network in Korea was shut down on December 31, 1999.

STI used the same 800MHz band that KMTC used for CDMA. This is because it was allocated a portion of the band originally used by KMTC: 835 - 845MHz uplink and 880 - 890MHz downlink for 10MHz each way. STI never offered AMPS and started its operation exclusively on CDMA.

Meanwhile, Korean government wanted a full-scale competitive telecommunication market, so it decided to introduce Personal Communications Service (PCS) based on the same CDMA technology used by cellular phones. Through MIC Notice No.1995-160(Oct. 30, 1995), the 1800MHz band (1750 - 1780MHz uplink, 1840 - 1870MHz downlink for 30MHz each) was allocated for this purpose.

As for the PCS carriers, three were selected on June 10, 1996: Korea Telecom Freetel (한국통신프리텔; KTF), Hansol PCS(한솔PCS), and LG Telecom (LG텔레콤; LGT; currently LG Uplus). KTF and Hansol PCS were ultimately absorbed by KT later. As per MIC Notice No.1997-27(Feb. 21, 1997), the band was divided into A, B, and C bands, 10MHz each, and allocated A to KTF, B to Hansol PCS, and C to LG Telecom. Commercial PCS networks went online on October 1, 1997.

The shape of the industry was kept more or less like this until the year 2000, when a sea of changes like the selection of IMT-2000 operators and various mergers transformed the landscape. As a side note, dialing codes for each carriers were 011 for SK Telecom(KMTC), 017 for Shinsegi Telecom, 016 for KTF, 018 for Hansol PCS, and 019 for LG Telecom.

[Frequency Allotment 1996 - 2000]

CDMA (2G) - Cellular
SKT #1: Uplink 824 - 835MHz (11MHz) / Downlink 869 - 880MHz (11MHz)
SKT #2: Uplink 845 - 849MHz (4MHz) / Downlink 890 - 894MHz (4MHz)
STI: Uplink 835 - 845MHz (10MHz) / Downlink 880 - 890MHz (10MHz)

CDMA (2G) - PCS
KTF: Uplink 1750 - 1760MHz (10MHz) / Downlink 1840 - 1850MHz (10MHz)
Hansol: Uplink 1760 - 1770MHz (10MHz) / Downlink 1850 - 1860MHz (10MHz)
LGT: Uplink 1770 - 1780MHz (10MHz) / Downlink 1860 - 1870MHz (10MHz)
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Cellphone frequency in Korea: 1984 - 1995

On December 10, 1981, South Korea's Ministry of Communications (체신부) separated the telecommunication sector from itself to form a public corporation called Korea Telecom (한국전기통신공사; currently KT Corporation) in order to modernize telecommunication service. And then, this company created a subsidiary called Korea Mobile Telecommunications Services Corporation (KMTSC; 한국이동통신서비스(주); currently SK Telecom) on March 29, 1984, to manage mobile telecommunication sector. In May of the same year, it started the "car phone" service based on the analog AMPS (1G) cellular phone technology around the Seoul metropolitan area. This marked the beginning of the mobile phone service in Korea.

The frequencies used at the time was 824 - 849MHz uplink and 869 - 894MHz downlink, which was 25MHz bandwidth each way. This is outlined in the Ministry of Communications Notice No.43 (May 9, 1991). KMTSC changed its name to Korea Mobile Telecommunications Corporation (KMTC; 한국이동통신(주)) as it was selected as a public common carrier on April 30, 1988. Nationwide AMPS network was set up by the end of 1991.

In 1994, a big restructuring effort was put into the telecommunications sector. In January, Sunkyong Group (선경그룹; currently SK Group) took over KMTC and privatized it by purchasing 24% of its stocks. Shinsegi Telecom Inc.(신세기통신(주); STI), which was selected to be the 2nd mobile carrier in Korea and had POSCO as its largest shareholder, was founded on May 2. This established the competitive market for mobile phone services.

Interestingly, Sunkyong Group was originally selected as the 2nd mobile carrier in 1992, but its CEO an in-law to the then-president Roh Tae-woo, sparking preferential treatment controversy. It relinquished the rights on August 27 of that year. It ended up entering the telecommunications market by buying up the 1st mobile carrier instead. KMTC changed its name to SK Telecom on March 1997 is called by that name to this day.

[Frequency Allotment 1984 - 1995]

AMPS (1G)
KMTC: Uplink 824 - 849MHz / Downlink 869 - 894MHz
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